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1.
JAMA Dermatol ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39083288

RESUMEN

Importance: Psoriasis is a chronic inflammatory skin disease with unmet needs for tailored treatment and therapy de-escalation strategies. Objective: To evaluate early intervention with and prolonging the dosing interval for guselkumab, a p19 subunit-targeted interleukin (IL)-23 inhibitor, in patients with moderate to severe psoriasis. Design, Setting, and Participants: The GUIDE clinical trial is an ongoing phase 3b, randomized, double-blinded trial conducted across 80 centers in Germany and France comprising 3 parts evaluating the impact of early disease intervention, prolonged dosing interval, and maintenance of response following treatment withdrawal among adults with moderate to severe plaque psoriasis. In study part 2, reported herein, first and last patient visits were September 2019 and March 2022, respectively. Interventions: In GUIDE part 1 (week [W]0-W28), patients received guselkumab, 100 mg, at W0, W4, W12, and W20. Those achieving a Psoriasis Area and Severity Index (PASI) of 0 at both W20 and W28 were termed super responders (SRes). In part 2 (W28-W68), SRes were randomized to guselkumab, 100 mg, every 8 weeks or every 16 weeks; non-SRes continued open-label guselkumab every 8 weeks. Main Outcomes and Measures: Primary objective was to demonstrate noninferiority (with a 10% margin) of guselkumab every 16 weeks vs every 8 weeks dosing among SRes for maintenance of disease control (PASI <3 at W68). Biomarker substudies assessed immunologic effects in skin and blood. Results: Overall, 822 patients received guselkumab in part 2 (297 [36.1%] SRes [every 8 weeks/every 16 weeks; n = 148/n = 149] and 525 [63.9%] non-SRes). Among SRes, mean (SD) age was 39.4 (14.1) years, 95 (32.0%) were female, and 202 (68.0%) were male. The primary end point of noninferiority for guselkumab every 16 weeks vs every 8 weeks in SRes was met (P = .001), with 91.9% (137/149; 90% CI, 87.3%-95.3%) of SRes receiving every 16 weeks and 92.6% (137/148; 90% CI, 88.0%-95.8%) of SRes receiving dosing every 8 weeks having PASI lower than 3 at W68. Clinical effects corresponded with immunologic changes; skin CD8-positive tissue-resident memory T (TRM)-cell count decreased quickly from baseline, remaining low in both dosing groups. Similarly, serum IL-17A, IL-17F, IL-22, and ß defensin (BD)-2 levels decreased significantly from baseline, remaining low in both dosing groups to W68. Guselkumab was well-tolerated; no new safety signals were identified. Conclusions and Relevance: Psoriasis treatment guidelines lack or provide inconsistent advice on patient stratification and treatment de-escalation. We present the first randomized trial providing evidence that, in patients with early complete skin clearance at 2 consecutive visits (W20 and W28), extending the guselkumab dosing interval may control disease activity. Trial Registration: ClinicalTrials.gov Identifier: NCT03818035.

2.
JACC Cardiovasc Interv ; 17(14): 1652-1663, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38749449

RESUMEN

BACKGROUND: Transcatheter aortic valve replacement (TAVR) in patients with bicuspid aortic valve (BAV) stenosis is technically challenging and is burdened by an increased risk of paravalvular regurgitation (PVR). OBJECTIVES: The aim of this study was to identify the incidence, predictors, and clinical outcomes of PVR after TAVR in Sievers type 1 BAV stenosis. METHODS: Consecutive patients with Sievers type 1 BAV stenosis undergoing TAVR with current-generation transcatheter heart valves (THVs) in 24 international centers were enrolled. PVR was graded as none/trace, mild, moderate, and severe according to echocardiographic criteria. The endpoint of major adverse events (MAEs), defined as a composite of all-cause death, stroke, or hospitalization for heart failure, was assessed at the last available follow-up. RESULTS: A total of 946 patients were enrolled. PVR occurred in 423 patients (44.7%)-mild, moderate, and severe in 387 (40.9%), 32 (3.4%), and 4 (0.4%) patients, respectively. Independent predictors of moderate or severe PVR were a larger virtual raphe ring perimeter (adjusted OR: 1.07; 95% CI: 1.02-1.13), severe annular or left ventricular outflow tract calcification (adjusted OR: 5.21; 95% CI: 1.45-18.77), a self-expanding valve (adjusted OR: 9.01; 95% CI: 2.09-38.86), and intentional supra-annular THV positioning (adjusted OR: 3.31; 95% CI: 1.04-10.54). At a median follow-up of 1.3 years (Q1-Q3: 0.5-2.4 years), moderate or severe PVR was associated with an increased risk of MAEs (adjusted HR: 2.52; 95% CI: 1.24-5.09). CONCLUSIONS: After TAVR with current-generation THVs in Sievers type 1 BAV stenosis, moderate or severe PVR occurred in about 4% of cases and was associated with an increased risk of MAEs during follow-up.


Asunto(s)
Insuficiencia de la Válvula Aórtica , Estenosis de la Válvula Aórtica , Válvula Aórtica , Enfermedad de la Válvula Aórtica Bicúspide , Prótesis Valvulares Cardíacas , Índice de Severidad de la Enfermedad , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Masculino , Femenino , Factores de Riesgo , Anciano , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Reemplazo de la Válvula Aórtica Transcatéter/mortalidad , Insuficiencia de la Válvula Aórtica/fisiopatología , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/etiología , Insuficiencia de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/mortalidad , Válvula Aórtica/cirugía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Válvula Aórtica/anomalías , Resultado del Tratamiento , Anciano de 80 o más Años , Incidencia , Factores de Tiempo , Enfermedad de la Válvula Aórtica Bicúspide/cirugía , Enfermedad de la Válvula Aórtica Bicúspide/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/cirugía , Enfermedades de las Válvulas Cardíacas/fisiopatología , Europa (Continente) , Medición de Riesgo , Diseño de Prótesis , Oportunidad Relativa , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/diagnóstico , Estudios Retrospectivos
3.
Nano Lett ; 24(22): 6488-6495, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38771151

RESUMEN

Understanding heating and cooling mechanisms in mesoscopic superconductor-semiconductor devices is crucial for their application in quantum technologies. Owing to their poor thermal conductivity, heating effects can drive superconducting-to-normal transitions even at low bias, observed as sharp conductance dips through the loss of Andreev excess currents. Tracking such dips across magnetic field, cryostat temperature, and applied microwave power allows us to uncover cooling bottlenecks in different parts of a device. By applying this "Joule spectroscopy" technique, we analyze heat dissipation in devices based on InAs-Al nanowires and reveal that cooling of superconducting islands is limited by the rather inefficient electron-phonon coupling, as opposed to grounded superconductors that primarily cool by quasiparticle diffusion. We show that powers as low as 50-150 pW are able to suppress superconductivity on the islands. Applied microwaves lead to similar heating effects but are affected by the interplay of the microwave frequency and the effective electron-phonon relaxation time.

4.
Int J Cardiol ; 410: 132179, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38761972

RESUMEN

BACKGROUND: Optimal strategies to manage embolization of transcatheter aortic valve implantation (TAVI) devices are unclear; valve-in-valve (ViV) is often used. We aimed to describe through one-single center experience its rate, causes, consequences, and management as well as the rate and relevance of commissural alignment (CA) in this context. METHODS: We identified across 1038 TAVI cases, those cases requiring ViV for the management of first device embolization. CA (absence or mild misalignment) after first and second device was assessed by CT or fluoroscopy. RESULTS: A total of 23 cases (2.2%) were identified, 52.3% embolized towards the aorta and 47.7% towards the ventricle. Suboptimal implant height (38%) and embolization at the time of post-dilation (23%) were the most frequent mechanisms together with greater rate of bicuspid valve (p < 0.001) and a trend to greater annular eccentricity. Procedural and 1-year death occurred in 13% and 34%, respectively (vs. 1.1% and 7.8% in the global cohort, p < 0.001). CA was present in 76.9% of the prostheses initially implanted but was only spontaneously achieved in 30.8% of the second ViV device. Adequate CA of both prostheses was identified in only two cases (8.7%). There were no cases of coronary obstruction. CONCLUSIONS: TAVI device embolization mechanisms can often be predicted and prevented. Mortality following bail-out ViV is higher than in regular TAVI procedures but 2/3 of these patients survived beyond 1-year follow-up. In them, valve degeneration or coronary re-access might be particularly challenging since CA was rarely achieved with both devices suggesting that greater efforts should be made in this regard.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Masculino , Femenino , Anciano , Anciano de 80 o más Años , Resultado del Tratamiento , Estenosis de la Válvula Aórtica/cirugía , Estudios Retrospectivos , Estudios de Seguimiento , Diseño de Prótesis , Embolia/etiología , Válvula Aórtica/cirugía , Válvula Aórtica/diagnóstico por imagen
6.
Mayo Clin Proc ; 99(3): 400-410, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38432746

RESUMEN

OBJECTIVE: To describe the evolution of symptoms in patients with symptomatic severe aortic stenosis (sSAS) undergoing valve replacement, the predictors of the persistence of these symptoms, and their prognostic significance. The evolution of symptoms after intervention in sSAS and their association with outcome are unknown. PATIENTS AND METHODS: Data from patients with sSAS who underwent intervention were collected. All-cause mortality and cardiovascular mortality were considered events. The evolution of symptoms and their association with events were studied. RESULTS: In this study, 451 consecutive patients with sSAS and no other valvular or coronary disease who were alive 30 days after intervention were included. Before valve replacement, 133 of the 451 patients (29.5%) had congestive heart failure requiring hospitalization. Of the remaining 318 patients, 287 (90.2%) had dyspnea on effort, 129 (40.6%) had angina, and 59 had syncope (18.6%). Symptoms disappeared after intervention in 192 of the 451 patients (42.6%) and remained in 259 (57.4%): 193 dyspnea, 9 angina, 17 syncope, and 60 admission for heart failure. Syncope on effort persisted in 4 of 33 patients (12.1%) and at rest in 11 of 20 (55.0%; P<.001). Age, body mass index, previous admission for heart failure, and chronic obstructive pulmonary disease were independently related to persistence of symptoms. Over a median follow-up of 56 months in our cohort of 451 patients, 129 deaths were registered (28.6%), 40 of which were cardiovascular (8.9%). Age, chronic obstructive pulmonary disease, chronic kidney disease, atrial fibrillation, heart failure, and persistence of symptoms were independently associated with all-cause mortality. CONCLUSION: Symptoms attributed to SAS remain after intervention in a high proportion of patients, particularly dyspnea on effort and syncope at rest. The persistence of symptoms after intervention identifies patients with poor outcome.


Asunto(s)
Estenosis de la Válvula Aórtica , Insuficiencia Cardíaca , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Pronóstico , Síncope , Constricción Patológica , Disnea/etiología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Medición de Resultados Informados por el Paciente , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/cirugía
7.
Chemosphere ; 353: 141597, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38432466

RESUMEN

The contamination of creek sediments near industrially nuclear dominated site presents significant environmental challenges, particularly in identifying and quantifying potentially toxic metal (loid)s (PTMs). This study aims to measure the extent of contamination and apportion related sources for nine PTMs in alpine creek sediments near a typical uranium tailing dam from China, including strontium (Sr), rubidium (Rb), manganese (Mn), lithium (Li), nickel (Ni), copper (Cu), vanadium (V), cadmium (Cd), zinc (Zn), using multivariate statistical approach and Sr isotopic compositions. The results show varying degrees of contamination in the sediments for some PTMs, i.e., Sr (16.1-39.6 mg/kg), Rb (171-675 mg/kg), Mn (224-2520 mg/kg), Li (11.6-78.8 mg/kg), Cd (0.31-1.38 mg/kg), and Zn (37.1-176 mg/kg). Multivariate statistical analyses indicate that Sr, Rb, Li, and Mn originated from the uranium tailing dam, while Cd and Zn were associated with abandoned agricultural activities, and Ni, Cu, and V were primarily linked to natural bedrock weathering. The Sr isotope fingerprint technique further suggests that 48.22-73.84% of Sr and associated PTMs in the sediments potentially derived from the uranium tailing dam. The combined use of multivariate statistical analysis and Sr isotopic fingerprint technique in alpine creek sediments enables more reliable insights into PTMs-induced pollution scenarios. The findings also offer unique perspectives for understanding and managing aqueous environments impacted by nuclear activities.


Asunto(s)
Metales Pesados , Uranio , Cadmio , Zinc , Manganeso , Níquel , Estroncio , Litio , Medición de Riesgo , China , Metales Pesados/análisis , Monitoreo del Ambiente/métodos , Sedimentos Geológicos
8.
Bioresour Technol ; 398: 130533, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38452950

RESUMEN

Liquid digestate of food waste is an ammonium-, ferric- and sulfate-laden leachate produced during digestate dewatering, where the carbon source is insufficient for nitrogen removal. A two-stage partial nitrification-anammox/denitrification process was established for nitrogen removal of liquid digestate without pre-treatment (>300 d), through which nitrogen (95 %), biodegradable organics (100 %), sulfate (78 %) and iron (100 %) were efficiently removed. Additional ammonium conversion (20 %N) might be coupled with ferric and sulfate reduction, while produced nitrite could be further converted to di-nitrogen gas through anammox (75 %) and denitrification (25 %). Notably, since increasingly contribution of hydroxylamine producing nitrous oxide, and up-regulated expression of electron transfer and cytochrome c protein, the enhanced ammonium oxidation was probably conducted through extracellular polymeric substances-mediated electron transfer between sulfate/ferric-reducers and aerobic ammonium oxidizers. Thus, the established partial nitrification-anammox/denitrification process might be a cost-efficient nitrogen removal technology for liquid digestate, benefitting to domestic waste recycling and carbon neutralization.


Asunto(s)
Compuestos de Amonio , Eliminación de Residuos , Nitrificación , Desnitrificación , Alimento Perdido y Desperdiciado , Nitrógeno , Sulfatos , Alimentos , Oxidación Anaeróbica del Amoníaco , Oxidación-Reducción , Hierro , Carbono , Reactores Biológicos , Aguas del Alcantarillado
9.
Environ Pollut ; 344: 123235, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38159635

RESUMEN

The extraction and utilization of uranium (U) ores have led to the release of significant amounts of potentially toxic metal(loid)s (PTMs) into the environment, constituting a grave threat to the ecosystem. However, research on the distribution and migration mechanism of U, chromium (Cr), and their accompanying PTMs in soil-plant system around U hydrometallurgical area remains insufficient and poorly understood. Herein, the distribution, migration, and risk level of PTMs were evaluated in soil and plant samples around U hydrometallurgical area, Northern Guangdong, China. The results demonstrated that the maximum content of U and Cr found in the analyzed soils were up to 84.2 and 238.9 mg/kg, respectively. These values far exceed the soil background values in China and other countries. The highest content of U (53.6 mg/kg) was detected in Colocasia antiquorum Schott, and the highest content of Cr (349.5 mg/kg) was observed in Pteridium aquilinum, both of which were enriched in their roots. The risk assessment of PTMs demonstrated that the study area suffered from severe pollution (PN > 3), especially from U, Cr, Th, and As, suggesting the non-negligible anthropogenic impacts. Hence, in light of the significant ecological hazard posed by the U hydrometallurgical area, it is imperative to implement appropriate restoration measures to ensure the human health and maintain the stability of the ecosystem.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Uranio , Humanos , Uranio/análisis , Metales Pesados/análisis , Cromo , Suelo , Ecosistema , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/análisis , China , Medición de Riesgo
11.
Microorganisms ; 11(12)2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38138066

RESUMEN

The bacterium strain Cetobacterium sp. C33 was isolated from the intestinal microbial content of Nile tilapia (O. niloticus) under anaerobic conditions. Given that Cetobacterium species are recognized as primary constituents of the intestinal microbiota in cultured Nile tilapia by culture-independent techniques, the adaptability of the C33 strain to the host gastrointestinal conditions, its antibacterial activity against aquaculture bacterial and its antibiotic susceptibility were assessed. The genome of C33 was sequenced, assembled, annotated, and subjected to functional inference, particularly regarding pinpointed probiotic activities. Furthermore, phylogenomic comparative analyses were performed including closely reported strains/species relatives. Comparative genomics with closely related species disclosed that the isolate is not phylogenetically identical to other Cetobacterium species, displaying an approximately 5% sequence divergence from C. somerae and a 13% sequence divergence from Cetobacterium ceti. It can be distinguished from other species through physiological and biochemical criteria. Whole-genome annotation highlighted that Cetobacterium sp. nov. C33 possesses a set of genes that may contribute to antagonism against competing bacteria and has specific symbiotic adaptations in fish. Additional in vivo experiments should be carried out to verify favorable features, reinforcing its potential as a probiotic bacterium.

12.
Front Immunol ; 14: 1259998, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38022533

RESUMEN

Opiate abuse increases the risk of HIV transmission and exacerbates HIV neuropathology by increasing inflammation and modulating immune cell function. Exosomal EVs(xEV) contain miRNAs that may be differentially expressed due to HIV infection or opiate abuse. Here we develop a preliminary exosomal-miRNA biomarker profile of HIV-infected PBMCs in the context of opiate use. PBMCs infected with HIV were treated with increasing dosages of morphine for 72 hours, the culture supernatants were collected, and the exosomes isolated using differential centrifugation. Exosomal miRNAs were extracted, expression levels determined via Nanostring multiplexed microRNA arrays, and analyzed with Webgestalt. The effect of the exosomes on neuronal function was determined by measuring calcium. Preliminary findings show that HIV-1 infection altered the miRNA profile of PBMC-derived EVs concurrently with opiate exposure. MicroRNA, hsa-miR-1246 was up-regulated 12-fold in the presence of morphine, relative to uninfected control. PBMCs infected with HIV-1 MN, an X4-tropic HIV-1 strain and exposed to morphine, displayed a trend which suggests potential synergistic effects between HIV-1 infection and morphine exposure promoting an increase in viral replication. Dose-dependent differences were observed in miRNA expression as a result of opiate exposure. The xEVs derived from PBMCs exposed to morphine or HIV modulated neuronal cell function. SH-SY5Y cells, treated with xEVs derived from ART-treated PBMCs, exhibited increased viability while for SH-SY5Ys exposed to xEVs derived from HIV-1 infected PBMCs viability was decreased compared to the untreated control. Exposing SH-SY5Y to xEVs derived from HIV-infected PBMCs resulted in significant decrease in calcium signaling, relative to treatment with xEVs derived from uninfected PBMCs. Overall, HIV-1 and morphine induced differential miRNA expression in PBMC-derived exosomes, potentially identifying mechanisms of action or novel therapeutic targets involved in opiate use disorder, HIV neuropathology, TNF signaling pathway, NF-κB signaling pathway, autophagy, and apoptosis in context of HIV infection.


Asunto(s)
Vesículas Extracelulares , Infecciones por VIH , Seropositividad para VIH , VIH-1 , MicroARNs , Neuroblastoma , Alcaloides Opiáceos , Trastornos Relacionados con Opioides , Humanos , VIH-1/fisiología , Infecciones por VIH/metabolismo , Alcaloides Opiáceos/metabolismo , Leucocitos Mononucleares/metabolismo , Neuroblastoma/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Vesículas Extracelulares/metabolismo , Morfina/farmacología
13.
Nat Commun ; 14(1): 7461, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37985656

RESUMEN

Neuroinflammation in the brain contributes to the pathogenesis of Parkinson's disease (PD), but the potential dysregulation of peripheral immunity has not been systematically investigated for idiopathic PD (iPD). Here we showed an elevated peripheral cytotoxic immune milieu, with more terminally-differentiated effector memory (TEMRA) CD8 T, CD8+ NKT cells and circulating cytotoxic molecules in fresh blood of patients with early-to-mid iPD, especially females, after analyzing > 700 innate and adaptive immune features. This profile, also reflected by fewer CD8+FOXP3+ T cells, was confirmed in another subcohort. Co-expression between cytotoxic molecules was selectively enhanced in CD8 TEMRA and effector memory (TEM) cells. Single-cell RNA-sequencing analysis demonstrated the accelerated differentiation within CD8 compartments, enhanced cytotoxic pathways in CD8 TEMRA and TEM cells, while CD8 central memory (TCM) and naïve cells were already more-active and transcriptionally-reprogrammed. Our work provides a comprehensive map of dysregulated peripheral immunity in iPD, proposing candidates for early diagnosis and treatments.


Asunto(s)
Enfermedad de Parkinson , Humanos , Femenino , Enfermedad de Parkinson/genética , Linfocitos T CD8-positivos , Diferenciación Celular , Memoria Inmunológica
14.
Nutrients ; 15(17)2023 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-37686880

RESUMEN

A single-center, randomized, double-blind, controlled clinical trial with four arms was conducted in healthy subjects with persistent knee discomfort (pain intensity on 1-10 cm visual analog scale (VAS) > 3) aged 40 years and older treated with a dietary supplement for 8 weeks. The study groups were Boswellia serrata extract (n = 29), an omega-3-based product (AvailOm® 50 High EPA) (n = 31), Boswellia + AvailOm® (n = 30), and placebo (n = 30). The intake of Boswellia + AvailOm® improved the quality of life (QoL) (WOMAC index) and some variables of muscle strength. Statistically significant differences between the AvailOm® and the placebo groups in the decrease of pain intensity were found. Weekly VAS scores showed a significant decrease in pain perception when comparing the AvailOm® product to the placebo, with the lowest VAS scores at week 8. Consumption of Boswellia improved sleep latency. The time to perform the Up and Go test decreased after the intake of AvailOm®. There was an increase in the omega-3 fatty acids, with the greatest increase in the Boswellia + AvailOm® group. AvailOm® was safe and effective in reducing pain and improving the QoL and functionality of subjects over 40 years with persistent knee pain.


Asunto(s)
Boswellia , Ácidos Grasos Omega-3 , Humanos , Adulto , Persona de Mediana Edad , Calidad de Vida , Dolor , Ácidos Grasos Omega-3/uso terapéutico , Extractos Vegetales/uso terapéutico
15.
Polymers (Basel) ; 15(15)2023 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-37571186

RESUMEN

Among the material extrusion technologies of additive manufacturing, fused granular fabrication is playing a bigger role in the industry. The increase in the size of printers demands extrusion systems with higher deposition rates that facilitate printing larger parts in shorter times with a need for cost reduction. This cost reduction in fused granular fabrication systems is due to the utilisation of pellets as the material source for the prints, such as pellets that are the most common way of distributing polymeric materials in industry and do not need the usual previous transformation into filaments. Most of the polymers in the industry can be found in the shape of pellets, so the opportunities for developing new materials beside the traditional filaments found in the market are expanding. In this research, a novel composite material has been developed based on the blending of commercial thermoplastic polyurethane (TPU) and cork particles obtained from industrial waste at different concentrations. These materials have been processed at a laboratory scale, and their mechanical, thermal and rheological properties have been studied. Despite a 53.52% reduction in the maximum stress on the x-axis, an 81.82% decrease in the values obtained with specimens oriented on the z-axis and a shortage in the deformation values, the results reveal a remarkable weight reduction leading to 21.31% when compared to the TPU of the blends,. These results may open a path to further explore these blends and find suitable applications in industry as proposed.

16.
Respir Care ; 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37311630

RESUMEN

BACKGROUND: High-flow nasal cannula (HFNC) reduces the need for intubation in adult subject with acute respiratory failure. Changes in hypobaric hypoxemia have not been studied for subject with an HFNC in ICUs at altitudes > 2,600 m above sea level. In this study, we investigated the efficacy of HFNC treatment in subjects with COVID-19 at high altitudes. We hypothesized that progressive hypoxemia and the increase in breathing frequency associated with COVID-19 in high altitudes affect the success of HFNC therapy and may also influence the performance of the traditionally used predictors of success and failure. METHODS: This was a prospective cohort study of subjects >18 y with a confirmed diagnosis of COVID-19-induced ARDS requiring HFNC who were admitted to the ICU. Subjects were followed up during the 28 d of HFNC treatment or until failure. RESULTS: One hundred and eight subjects were enrolled. At admission to the ICU, FIO2 delivery between 0.5-0.8 (odds ratio 0.38 [95% CI 0.17-0.84]) was associated with a better response to HFNC therapy than oxygen delivery on admission between 0.8-1.0 (odds ratio 3.58 [95% CI 1.56-8.22]). This relationship continued during follow-ups at 2, 6, 12, and 24 h, with a progressive increase in the risk of failure (odds ratio 24 h 13.99 [95% CI 4.32-45.26]). A new cutoff for the ratio of oxygen saturation (ROX) index (ROX ≥ 4.88) after 24 h of HFNC administration was demonstrated to be the best predictor of success (odds ratio 11.0 [95% CI 3.3-47.0]). CONCLUSIONS: High-altitude subjects treated with HFNC for COVID-19 showed a high risk of respiratory failure and progressive hypoxemia when FIO2 requirements were > 0.8 after 24 h of treatment. In these subjects, personalized management should include continuous monitoring of individual clinical conditions (such as oxygenation indices, with cutoffs adapted to those corresponding to high-altitude cities).

17.
Heart ; 109(21): 1631-1638, 2023 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-37286345

RESUMEN

OBJECTIVE: The recurrence of syncope after valve intervention in severe aortic stenosis (SAS) and its impact on outcome are unknown. We hypothesised that syncope on exertion will disappear after intervention, whereas syncope at rest might recur. Our aim has been to describe the recurrence of syncope in patients with SAS undergoing valve replacement and its impact on mortality. METHODS: Double-centre observational registry of 320 consecutive patients with symptomatic SAS without other valve disease and/or coronary artery disease who underwent valve intervention and were discharged alive. All-cause mortality and cardiovascular mortality were considered events. RESULTS: 53 patients (median age 81 years, 28 men) had syncope (29 on exertion, 21 at rest, 3 unknown). Clinical and echocardiographic variables were similar in patients with and without syncope (median vmax 4.44 m/s, mean gradient 47 mm Hg, valve area 0.7 cm2, left ventricular ejection fraction 62%). After a median follow-up of 69 months (IQR: 55-88), syncope on exertion did not recur in any patient. In contrast, 8 of the 21 patients with syncope at rest had postintervention syncope at rest (38%; p<0.001): 3 needed a pacemaker, 3 were neuromediated or hypotensive and 2 arrhythmic. Only recurrence of syncope was associated with cardiovascular mortality (HR 5.74; 95% CI 2.17 to 15.17; p<0.001). CONCLUSIONS: Syncope on exertion in patients with SAS did not recur after aortic valve intervention. Syncope at rest recurs in a high proportion of patients and identifies a population with increased mortality. According to our results, syncope at rest should be thoroughly evaluated before proceeding to aortic valve intervention.


Asunto(s)
Estenosis de la Válvula Aórtica , Reemplazo de la Válvula Aórtica Transcatéter , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/cirugía , Índice de Severidad de la Enfermedad , Volumen Sistólico , Síncope/diagnóstico , Síncope/etiología , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del Tratamiento , Función Ventricular Izquierda
18.
Am J Surg ; 226(6): 785-789, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37301645

RESUMEN

BACKGROUND: Prognostic significance of different anticoagulants in TBI patients remains unanswered. We aimed to compare effects of different anticoagulants on outcomes of TBI patients. METHODS: A secondary analysis of AAST BIG MIT. Blunt TBI patients ≥50 years using anticoagulants presenting ICH were identified. Outcomes were progression of ICH and need for neurosurgical intervention (NSI). RESULTS: 393 patients were identified. Mean age was 74 and most common anticoagulant was aspirin (30%), followed by Plavix (28%), and coumadin (20%). 20% had progression of ICH and 10% underwent NSI. On multivariate regression for ICH progression, warfarin, SDH, IPH, SAH, alcohol intoxication and neurologic exam deterioration were associated with increased odds. Warfarin, abnormal neurologic exam on presentation, and SDH were independent predictors of NSI. CONCLUSIONS: Our findings reflect a dynamic interaction between type of anticoagulants, bleeding pattern & outcomes. Future modifications of BIG may need to take the type of anticoagulant into consideration.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Warfarina , Humanos , Anciano , Warfarina/efectos adversos , Estudios Retrospectivos , Anticoagulantes/efectos adversos , Aspirina/efectos adversos
19.
Res Sq ; 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37214960

RESUMEN

Exosomal extracellular vesicles (xEVs) in plasma and cerebrospinal fluid (CSF) of aviremic people living with HIV/AIDS (PLWHA) contain the HIV Negative factor (Nef) protein. However, the role of xEVs and Nef-containing-xEVs(xEV-Nef) in HIV-associated neuropathology is unknown. Here we performed a cross-sectional analysis of the content of xEVs derived from matched serum and CSF samples of PLWHAs diagnosed with either asymptomatic neurocognitive impairment (ANI), mild neurocognitive disorder (MND), or HIV-associated dementia (HAD). The overall objective was to determine whether the content of the matched xEVs derived plasma or CSF correlated with the neurocognitive impairment (NCI) status. The size and protein content of the xEVs were characterized via dynamic light scattering (DLS) and LC-MS/MS, respectively. xEV size was not significantly different between ANI, MND, or HAD groups. CSF of PLWHAs with NCI contained significantly more xEVs than matched plasma. xEV-Nef CSF concentration was elevated in PLWHAs with NCI and correlated with CD4 T-cell count. Plasma-derived xEV protein profiles from PLWHAs with ANI or MND differed from PLWHAs without NCI. Over-representation analysis using Reactome and KEGG databases show proteins involved in pathways associated with heme scavenging, signaling(MAP kinase and integrin-alpha),Toll-like receptor regulation, clot formation, complement, and cytosolic calcium level were elevated in MND. Pathways upregulated within the ANI group involved high-density lipid (HDL) remodeling, post-translational protein phosphorylation, and platelet activation. Overall, the data shows that xEV protein profiles of ANI and MND differ, suggesting protein profiles of peripheral xEVs, xEV-Nef, and CD4 T-cell count may discern NCI status.

20.
Materials (Basel) ; 16(10)2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37241299

RESUMEN

Today, shape memory alloys (SMAs) have important applications in several fields of science and engineering. This work reports the thermomechanical behavior of NiTi SMA coil springs. The thermomechanical characterization is approached starting from mechanical loading-unloading tests under different electric current intensities, from 0 to 2.5 A. In addition, the material is studied using dynamic mechanical analysis (DMA), which is used to evaluate the complex elastic modulus E* = E' - iE″, obtaining a viscoelastic response under isochronal conditions. This work further evaluates the damping capacity of NiTi SMA using tan δ, showing a maximum around 70 °C. These results are interpreted under the framework of fractional calculus, using the Fractional Zener Model (FZM). The fractional orders, between 0 and 1, reflect the atomic mobility of the NiTi SMA in the martensite (low-temperature) and austenite (high-temperature) phases. The present work compares the results obtained from using the FZM with a proposed phenomenological model, which requires few parameters for the description of the temperature-dependent storage modulus E'.

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