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1.
Glob Chang Biol ; 30(8): e17481, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39161269

RESUMO

Rising global temperatures present unprecedented challenges to marine ecosystems, demanding a profound understanding of their ecological dynamics for effective conservation strategies. Over a comprehensive macroalgal assessment spanning three decades, we investigated the spatiotemporal evolution of shallow-water benthic communities in the southern Bay of Biscay, uncovering climate-resilient areas amidst the ongoing phase shift in the region. Our investigation identified seven locations serving as potential climate refugia, where cold-affinity, canopy-forming macroalgal species persisted and community structure was similar to that observed in 1991. We unveiled a clear association between the emergence of these refugia, sea surface temperature (SST), and the Community Temperature Index, positioning SST as a significant driver of the observed phase shift in the region. Warming processes, defined as tropicalization (increase of warm-affinity species) and deborealization (decrease of cold-affinity species), were prominent outside refugia. In contrast, cooling processes, defined as borealization (increase of cold-affinity species) and detropicalization (decrease of warm-affinity species), prevailed inside refugia. Refugia exhibited approximately 35% lower warming processes compared to non-refuge areas. This resulted in a dominance of warm-affinity species outside refugia, contrasting with the stability observed within refugia. The persistence of canopy-forming species in refuge areas significantly contributed to maintaining ecosystem diversity and stability. These findings underscored the pivotal role of climate refugia in mitigating climate-driven impacts. Prioritizing the protection and restoration of these refugia can foster resilience and ensure the preservation of biodiversity for future generations. Our study illustrates the importance of refining our understanding of how marine ecosystems respond to climate change, offering actionable insights essential for informed conservation strategies and sustainable environmental management.


Assuntos
Mudança Climática , Refúgio de Vida Selvagem , Alga Marinha , Temperatura , Alga Marinha/fisiologia , Baías , Ecossistema , Biodiversidade
2.
Cancer Metab ; 12(1): 3, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273418

RESUMO

BACKGROUND: The C-reactive protein (CRP)-triglyceride-glucose (TyG) index (CTI), which is a measure representing the level of inflammation and insulin resistance (IR), is related to poor cancer prognosis; however, the CTI has not been validated in patients with cancer cachexia. Thus, this study aimed to explore the potential clinical value of the CTI in patients with cancer cachexia. METHODS: In this study, our prospective multicenter cohort included 1411 patients with cancer cachexia (mean age 59.45 ± 11.38, 63.3% male), which was a combined analysis of multiple cancer types. We randomly selected 30% of the patients for the internal test cohort (mean age 58.90 ± 11.22% 61.4% male). Additionally, we included 307 patients with cancer cachexia in the external validation cohort (mean age 61.16 ± 11, 58.5% male). Receiver operating characteristic (ROC) and calibration curves were performed to investigate the prognostic value of CTI. The prognostic value of the CTI was also investigated performing univariate and multivariate survival analyses. RESULTS: The survival curve indicated that the CTI showed a significant prognostic value in the total, internal, and external validation cohorts. Prognostic ROC curves and calibration curves revealed that the CTI showed good consistency in predicting the survival of patients with cancer cachexia. Multivariate survival analysis showed that an elevated CTI increased the risk of death by 22% (total cohort, 95% confidence interval [CI] = 1.13-1.33), 34% (internal test cohort, 95%CI = 1.11-1.62), and 35% (external validation cohort, 95%CI = 1.14-1.59) for each increase in the standard deviation of CTI. High CTI reliably predicted shorter survival (total cohort, hazard ratio [HR] = 1.45, 95%CI = 1.22-1.71; internal test cohort, HR = 1.62, 95%CI = 1.12-2.36; external validation cohort, HR = 1.61, 95%CI = 1.15-2.26). High CTI significantly predicted shorter survival in different tumor subgroups, such as esophageal [HR = 2.11, 95%CI = 1.05-4.21] and colorectal cancer [HR = 2.29, 95%CI = 1.42-3.71]. The mediating effects analysis found that the mediating proportions of PGSGA, ECOG PS, and EORTC QLQ-C30 on the direct effects of CTI were 21.72%, 19.63%, and 11.61%, respectively We found that there was a significant positive correlation between the CTI and 90-day [HR = 2.48, 95%CI = 1.52-4.14] and 180-day mortality [HR = 1.77,95%CI = 1.24-2.55] in patients with cancer cachexia. CONCLUSION: The CTI can predict the short- and long-term survival of patients with cancer cachexia and provide a useful prognostic tool for clinical practice.

3.
Sensors (Basel) ; 24(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38203154

RESUMO

Machine learning (ML) has found widespread application in various domains. Additionally, ML-based techniques have been employed to address security issues in technology, with numerous studies showcasing their potential and effectiveness in tackling security problems. Over the years, ML methods for identifying malicious software have been developed across various security domains. However, recent research has highlighted the susceptibility of ML models to small input perturbations, known as adversarial examples, which can significantly alter model predictions. While prior studies on adversarial examples primarily focused on ML models for image processing, they have progressively extended to other applications, including security. Interestingly, adversarial attacks have proven to be particularly effective in the realm of malware classification. This study aims to explore the transparency of malware classification and develop an explanation method for malware classifiers. The challenge at hand is more complex than those associated with explainable AI for homogeneous data due to the intricate data structure of malware compared to traditional image datasets. The research revealed that existing explanations fall short in interpreting heterogeneous data. Our employed methods demonstrated that current malware detectors, despite high classification accuracy, may provide a misleading sense of security and measuring classification accuracy is insufficient for validating detectors.

4.
Mar Environ Res ; 195: 106351, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38219379

RESUMO

Global warming is triggering significant shifts in temperate macroalgal communities worldwide, favoring small, warm-affinity species over large canopy-forming, cold-affinity species. The Cantabrian Sea, a region acutely impacted by climate change, is also witnessing this shift. This study delved into the impacts of increasing sea surface temperature on the subtidal macroalgal communities in the southeastern Bay of Biscay over the last four decades, by using data from the years 1982, 2007, 2014, and 2020. We found that temperature has shaped the community structure, with warm-affinity species steadily displacing their cold-affinity counterparts. Notably, new communities exhibited a profusion of smaller algal species, explaining the observed increased biodiversity within the area. In the last period investigated (2014-2020), we observed a partial recovery of the communities, coinciding with cooler sea surface temperatures. Shallow algal communities were more reactive to temperature variations than deeper communities, possibly associated with higher exposure to increased temperatures. Our study offered insights into the intricate relationship between the changes in ocean temperature and algal species in the southeastern Bay of Biscay, shedding light on the ongoing ecological shifts in this region.


Assuntos
Alga Marinha , Temperatura , Baías , Biodiversidade , Mudança Climática , Ecossistema
5.
J Electrocardiol ; 82: 69-72, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38042010

RESUMO

We present a case of a patient with advanced interatrial block who was admitted for cavotricuspid isthmus ablation as treatment of typical atrial flutter. A baseline advanced interatrial block pattern turned into partial interatrial block pattern and prolonged PR interval after the procedure. We discuss the mechanism underlying that change.


Assuntos
Flutter Atrial , Ablação por Cateter , Humanos , Sistema de Condução Cardíaco/cirurgia , Resultado do Tratamento , Bloqueio Interatrial , Eletrocardiografia/métodos , Flutter Atrial/cirurgia , Ablação por Cateter/métodos
6.
Rev. adm. pública (Online) ; 58(2): e20230096, 2024. tab, graf
Artigo em Inglês, Português | LILACS | ID: biblio-1559195

RESUMO

Resumo Este estudo tem como objetivo analisar criticamente os mecanismos que desidratam o Fundo Nacional de Desenvolvimento Científico e Tecnológico (FNDCT), debilitando-o na sua função de promover o desenvolvimento econômico e social. Os dados foram extraídos das bases do sistema integrado de orçamento e planejamento (SIOP) e do relatório de execução orçamentária, entre 2012 e 2021, disponibilizados pela financiadora de estudos e projetos (FINEP). Os resultados da investigação apontam que, do ponto de vista quantitativo, há um processo de desidratação, por mecanismos como a desvinculação de receitas da união (DRU), a formulação do projeto de lei orçamentária anual (PLOA) e as reservas de contingência. Do lado qualitativo, há descompasso entre a promessa de uma política arrojada e inovadora e uma estrutura de governança centralizada e burocrática. Os fundos setoriais não enfrentam problemas de arrecadação, mas a gestão centralizada e subserviente a políticas fiscais de austeridade leva a uma execução orçamentária quantitativamente insuficiente e qualitativamente pobre em diversificação, quadro que descaracteriza a política de financiamento de ciência, tecnologia e inovação (CT&I), deixando de cumprir a promessa de desenvolvimento via inovação.


Resumen Este estudio tiene como objetivo analizar críticamente los mecanismos que deshidratan el fondo nacional de desarrollo científico y tecnológico (FNDCT), debilitándolo en su función de promover el desarrollo económico y social. Los datos fueron extraídos de las bases del sistema integrado de planificación y presupuesto y del informe de ejecución presupuestaria entre 2012 y 2021, puestos a disposición por la financiadora de estudios y proyectos. Los resultados de la investigación indican que, desde el punto de vista cuantitativo, existe un proceso de deshidratación, a través de mecanismos como la Desvinculación de Ingresos de la Unión Federal, la formulación del proyecto de ley presupuestaria anual y las reservas de contingencia. En el aspecto cualitativo, existe un desajuste entre la promesa de una política audaz e innovadora y una estructura de gobierno centralizada y burocrática. Los fondos sectoriales no enfrentan, en promedio, problemas de recaudación, pero la gestión centralizada supeditada a políticas fiscales de austeridad conduce a una ejecución presupuestaria cuantitativamente insuficiente y cualitativamente pobre en términos de diversificación, situación que descaracteriza la política de financiamiento para la ciencia, tecnología e innovación (CT&I), incumpliendo con la promesa de desarrollo a través de la innovación.


Abstract This study aims to critically analyze the mechanisms that depletethe Brazilian fund for the development of science and technology (FNDCT), jeopardizing its ability to promote economic and social development. Data were extracted from the integrated budget and planning system (SIOP) bases and the budget execution report between 2012 and 2021, made available by the Brazilian funding agency FINEP. The quantitative results indicate a process of "dehydration" due to changes such as the regulation that allows the executive to redirect resources previously earmarked for the fund (called DRU), the formulation of the legislation on the annual budget (PLOA) and the contingency reserves. The qualitative analysis shows a mismatch between the promise of a bold and innovative science and technology policy and a centralized and bureaucratic governance structure. Sectoral funds do not face, on average, problems in raising resources. However, the centralized management subservient to fiscal austerity policies leads to quantitative insufficient budget execution and qualitatively poor diversification. As outcomes, this situation mischaracterizes the ST&I funding policy, failing to comply with the promise of development through innovation.


Assuntos
Mudança Social , Orçamentos , Desenvolvimento Econômico
7.
J Clin Med ; 12(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37834921

RESUMO

Atrial flutter (AFL) represents a prevalent variant of supraventricular tachycardia, distinguished by a macro-reentrant pathway encompassing the cavotricuspid isthmus (CTI). Radiofrequency (RF) catheter ablation stands as the favored therapeutic modality for managing recurring CTI-dependent AFL. Intracardiac echocardiography (ICE) has been proposed as a method to reduce radiation exposure during CTI ablation. This study aims to comprehensively compare procedural parameters between ICE-guided CTI ablation and fluoroscopy-only procedures. A total of 370 consecutive patients were enrolled in our single-center retrospective study. In 151 patients, procedures were performed using fluoroscopy guidance only, while 219 patients underwent ICE-guided CTI ablation. ICE guidance significantly reduced fluoroscopy time (73 (36; 175) s vs. 900 (566; 1179) s; p < 0.001), fluoroscopy dose (2.45 (0.6; 5.1) mGy vs. 40.5 (25.7; 62.9) mGy; p < 0.001), and total procedure time (70 (52; 90) min vs. 87.5 (60; 102.5) min; p < 0.001). Total ablation time (657 (412; 981) s vs. 910 (616; 1367) s; p < 0.001) and the time from the first to last ablation (20 (11; 36) min vs. 40 (25; 55) min; p < 0.01) were also significantly shorter in the ICE-guided group. Acute success rate was 100% in both groups, and no major complications occurred in either group. ICE-guided CTI ablation in patients with AFL resulted in shorter procedure times, reduced fluoroscopy exposure, and decreased ablation times, compared to the standard fluoroscopy-only approach.

8.
Mar Environ Res ; 190: 106098, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37453282

RESUMO

Climate change is causing significant shifts in biological communities worldwide, including the degradation of marine communities. Previous research has predicted that southern Bay of Biscay canopy-forming subtidal macroalgal communities will shift into turf-forming Mediterranean-like communities by the end of the century. These predictions were based on a community-environment relationship model that used macroalgal abundance data and IPCC environmental projections. We have tested the short-term accuracy of that model by resampling the same communities and locations four years later and found the short-term predictions to be consistent with the observed communities. Changes in sea surface temperature were positively correlated with changes in the Community Temperature Index, suggesting that macroalgal communities had responded quickly to global warming. The changes over four years were significant, but canopy-forming macroalgae were more resilient in local sites with favourable temperature conditions. Our study demonstrated that updating predictive models with new data has the potential to yield reliable predictions and inform effective conservation strategies.


Assuntos
Baías , Alga Marinha , Alga Marinha/fisiologia , Mudança Climática , Aquecimento Global , Biota , Ecossistema
9.
J Interv Card Electrophysiol ; 66(7): 1749-1757, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36869990

RESUMO

BACKGROUND: A novel ablation catheter has been released to map and ablate the cavo-tricuspid isthmus (CTI) in patients with atrial flutter (AFL), improving ablation efficiency. METHODS: We evaluated the acute and long-term outcome of CTI ablation aiming at bidirectional conduction block (BDB) in a prospective, multicenter cohort study enrolling 500 patients indicated for typical AFL ablation. Patients were grouped on the basis of the AFL ablation method (linear anatomical approach, Conv group n = 425, or maximum voltage guided, MVG group, n = 75) and ablation catheter (mini-electrodes technology, MiFi group, n = 254, or a standard 8-mm ablation catheter, BLZ group, n = 246). RESULTS: Complete BDB according to both validation criteria (sequential detailed activation mapping or mapping only the ablation site) was achieved in 443 patients (88.6%). The number of RF applications needed to achieve BDB was lower in the MiFi MVG group vs both the MiFi Conv group and the BLZ Conv group (3.2 ± 2 vs 5.2 ± 4 vs 9.3 ± 5, p < 0.0001 for all comparisons). Fluoroscopy time was similar among groups, whereas we observed a reduction in the procedure duration from the BLZ Conv group (61.9 ± 26min) to the MiFi MVG group (50.6 ± 17min, p = 0.048). During a mean follow-up of 548 ± 304 days, 32 (6.2%) patients suffered an AFL recurrence. No differences were found according to BDB achieved by both validation criteria. CONCLUSIONS: Ablation was highly effective in achieving acute CTI BDB and long-term arrhythmia freedom irrespective of the ablation strategy or the validation criteria for CTI chosen by the operator. The use of an ablation catheter equipped with mini-electrodes technology seems to improve ablation efficiency. CLINICAL TRIAL REGISTRATION: Atrial Flutter Ablation in a Real World Population. (LEONARDO). CLINICALTRIALS: gov Identifier: NCT02591875.


Assuntos
Flutter Atrial , Ablação por Cateter , Humanos , Flutter Atrial/diagnóstico por imagem , Flutter Atrial/cirurgia , Ablação por Cateter/métodos , Estudos de Coortes , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Resultado do Tratamento , Estudos Clínicos como Assunto
10.
Medicina (Bogotá) ; 45(1): 49-57, 2023.
Artigo em Espanhol | LILACS | ID: biblio-1435199

RESUMO

Los sistemas de salud en todo el mundo están sufriendo transformaciones como consecuencia de situaciones que ejercen presiones de índole diversa que hacen no solo pertinente sino necesaria una reflexión acerca de los procesos formativos tanto de los profesionales de la salud como de las comunidades y personas del común, para que unos y otros sean partícipes de la construcción de condiciones adecuadas y sostenibles de salud y bienestar, en especial para todas y todos los colombianos. Sin embargo, tales acciones educativas requieren una articulación eficiente con un sistema de ciencia, tecnología e innovación en salud que permita la producción y apropiación de conocimiento en la frontera científica, así como la apropiación social por todos los actores sociales, de manera que se promuevan procesos de innovación tecnológica y social para responder a las necesidades y desafíos más urgentes de la salud individual y colectiva. En particular, se reflexiona sobre la necesidad de asumir lineamientos mundiales como los Objetivos de Desarrollo Sostenible y las propuestas de la Organización Mundial de la Salud. Adicionalmente, se propone tener en cuenta las ocho propuestas generales del foco de ciencias de la vida y de la salud de la Misión de Sabios 2019, así como las reflexiones particulares sobre educación para la salud: educación para una vida con bienestar, educación en salud: formación académica y profesional y educación para aportar a las acciones del sistema de salud.


Health systems around the world are undergoing transformations because of situations that exert pressures of a diverse type that make it not only pertinent, but also necessary, to analyze and modify the training processes of both health professionals and people of communities, so that both can take part in the construction of adequate and sustainable conditions of health and well-being, especially for all Colombians. However, such educational actions require an efficient articulation with a science, technology and innovation health system that allows the production and appropriation of knowledge in the scientific frontier, as well as the social appropriation by all social actors, so that they can develop processes of technological and social innovation to respond to the most urgent needs and challenges of individual and collective health. This paper reflects on the need to assume global guidelines such as the sustainable development goals and the proposals of the World Health Organization. Additionally, it considers the eight general proposals of the focus on life and health sciences of the Mission of Experts 2019, as well as the particular reflections on Health Education: education for a life with well-being, Health Education: academic and professional training, and Education to contribute to the actions of the health system.


Assuntos
Educação Médica , Desenvolvimento Sustentável
11.
JACC Adv ; 2(2): 100271, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38938299

RESUMO

Background: The use of transcatheter aortic valve implantation (TAVI) in patients with aortic valve disease excluded from clinical trials has increased with no large-scale data on its safety. Objectives: The purpose of this study was to assess the trend of utilization and adjusted outcomes of TAVI in clinical trials excluded (CTE) vs clinical trials included TAVI (CTI-TAVI) patients. Methods: We used the National Readmission Database (2015-2019) to identify 15 CTE-TAVI conditions. A propensity score-matched analysis was used to calculate the adjusted odds ratio (aOR) of net adverse clinical events (composite of mortality, stroke, and major bleeding) in patients undergoing CTE-TAVI vs CTI-TAVI. Results: Among the 223,238 patients undergoing TAVI, CTE-TAVI was used in 41,408 patients (18.5%). The yearly trend showed a steep increase in CTE-TAVI utilization (P = 0.026). At index admission, the adjusted odds of net adverse clinical events (aOR: 1.83, 95% CI: 1.73-1.95) and its components, including mortality (aOR: 2.94, 95% CI: 2.66-3.24), stroke (aOR: 1.20, 95% CI: 1.07-1.34), and major bleeding (aOR: 1.49, 95% CI: 1.36-1.63) were significantly higher in CTE-TAVI compared with CTI-TAVI. Among the individual contraindications to clinical trial enrollment in the CTE-TAVI, patients with bicuspid aortic valve, leukopenia, and peptic ulcer disease appeared to have similar outcomes compared with CTI-TAVI, while patients with end-stage renal disease, bioprosthetic aortic valves, and coagulopathy had a higher readmission rate at 30 and 180 days. Conclusions: CTE-TAVI utilization has increased significantly over the 4-year study period. Patients undergoing CTE-TAVI have a higher likelihood of mortality, stroke, and bleeding than those undergoing CTI-TAVI.

12.
Microbiol Spectr ; 10(5): e0102122, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36036638

RESUMO

Rice blast disease caused by Magnaporthe oryzae is a serious threat to global grain yield and food security. Cti6 is a nuclear protein containing a plant homeodomain (PHD) that is involved in transcriptional regulation in Saccharomyces cerevisiae. The biological function of its homologous protein in M. oryzae has been elusive. Here, we report Clp1 with a PHD domain in M. oryzae, a homologous protein of the yeast Cti6. Clp1 was mainly located in the nucleus and partly in the vesicles. Clp1 colocalized and interacted with the autophagy-related proteins Atg5, Atg7, Atg16, Atg24, and Atg28 at preautophagosomal structures (PAS) and autophagosomes, and the loss of Clp1 increased the fungal background autophagy level. Δclp1 displayed reduced hyphal growth and hyperbranching, abnormal fungal morphology (including colony, spore, and appressorium), hindered appressorial glycogen metabolism and turgor production, weakened plant infection, and decreased virulence. The PHD is indispensable for the function of Clp1. Therefore, this study revealed that Clp1 regulates development and pathogenicity by maintaining autophagy homeostasis and affecting gene transcription in M. oryzae. IMPORTANCE The fungal pathogen Magnaporthe oryzae causes serious diseases of grasses such as rice and wheat. Autophagy plays an indispensable role in the pathogenic process of M. oryzae. Here, we report a Cti6-like protein, Clp1, that is involved in fungal development and infection of plants through controlling autophagy homeostasis in the cytoplasm and gene transcription in the nucleus in M. oryzae. This study will help us to understand an elaborated molecular mechanism of autophagy, gene transcription, and virulence in the rice blast fungus.


Assuntos
Magnaporthe , Oryza , Magnaporthe/genética , Magnaporthe/metabolismo , Virulência , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação Fúngica da Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Doenças das Plantas/microbiologia , Oryza/genética , Oryza/metabolismo , Oryza/microbiologia , Autofagia , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proteínas Nucleares/metabolismo , Homeostase , Glicogênio/metabolismo , Esporos Fúngicos
14.
Pathogens ; 11(2)2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35215182

RESUMO

Human alveolar echinococcosis (AE), which is caused by the cestode Echinococcus (E.) multilocularis, is an epidemiologically relevant issue in modern medicine and still poses a diagnostic and therapeutic challenge. Since diagnosis mainly relies on imaging procedures and serological testing, we retrospectively and comparatively analyzed the performance of an Echinococcus IgG screening ELISA, whole serum IgE, and two specific confirmatory ELISA platforms using the defined E. multilocularis antigens Em2-Em18 (Em2+) and recombinant Em18 (recEm18). With special emphasis on the clinical usefulness of recEm18, we correlated the laboratory results with clinical characteristics and imaging findings in a large and well-characterized cohort of N = 124 AE patients, who were followed over several years after either surgical plus subsequent pharmacological treatment or pharmacotherapy alone. All patients had routinely received PET-CTI every two years. Our data reveal strong correlations for both Echinococcus IgG and recEm18 with tracer uptake in PET-CTI and parasitic lesion size and number, suggesting additional clinical usefulness of recEm18 for certain constellations only, while IgG and Em2+ still appear reasonable and sensitive screening methods for initial diagnosis of AE. With this study, we aim to contribute to further optimizing medical care of AE patients. For instance, it might be reasonable to consider the replacement of some PET-CTI follow-ups by imaging procedures with less radiation exposure or serological means alone. Further studies that clarify the correlation of serological markers with ultrasound criteria might be particularly useful, and further retrospective as well as prospective investigations are justified in this context.

15.
JACC Basic Transl Sci ; 7(12): 1249-1261, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36644275

RESUMO

A new device called the Pivot-TR system was designed to treat tricuspid regurgitation with a novel spacer crossing the valve vertically. Its unique atraumatic anchoring system composed of both the elephant long nose and the inferior vena cava spiral anchor, in addition to the relatively easy implantation mechanism, enabled easy retrieval of the system later on. The system showed promising feasibility and safety results in this swine-based animal experiment, which should encourage human translation study.

16.
Molecules ; 26(18)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34576970

RESUMO

Imaging of the electrical conductivity distribution inside the human body has been investigated for numerous clinical applications. The conductivity tensors of biological tissue have been obtained from water diffusion tensors by applying several models, which may not cover the entire phenomenon. Recently, a new conductivity tensor imaging (CTI) method was developed through a combination of B1 mapping, and multi-b diffusion weighted imaging. In this study, we compared the most recent CTI method with the four existing models of conductivity tensors reconstruction. Two conductivity phantoms were designed to evaluate the accuracy of the models. Applied to five human brains, the conductivity tensors using the four existing models and CTI were imaged and compared with the values from the literature. The conductivity image of the phantoms by the CTI method showed relative errors between 1.10% and 5.26%. The images by the four models using DTI could not measure the effects of different ion concentrations subsequently due to prior information of the mean conductivity values. The conductivity tensor images obtained from five human brains through the CTI method were comparable to previously reported literature values. The images by the four methods using DTI were highly correlated with the diffusion tensor images, showing a coefficient of determination (R2) value of 0.65 to 1.00. However, the images by the CTI method were less correlated with the diffusion tensor images and exhibited an averaged R2 value of 0.51. The CTI method could handle the effects of different ion concentrations as well as mobilities and extracellular volume fractions by collecting and processing additional B1 map data. It is necessary to select an application-specific model taking into account the pros and cons of each model. Future studies are essential to confirm the usefulness of these conductivity tensor imaging methods in clinical applications, such as tumor characterization, EEG source imaging, and treatment planning for electrical stimulation.


Assuntos
Condutividade Elétrica , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Anisotropia , Imagens de Fantasmas
17.
Transl Pediatr ; 10(8): 2044-2051, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34584874

RESUMO

BACKGROUND: The surface topography index (STI) has great potential in both routine computed tomography (CT) scan and emerging optical imaging systems. However, the diagnostic accuracy and stability of the STI as a deformity severity assessment index has not been fully confirmed. Therefore, the aim of the present study was to determine the diagnostic performance of the STI as a novel deformity severity assessment index for pectus excavatum. METHODS: The present study consisted of 722 chest CT images from a single center. The standard CT index (CTI) and STI were calculated for all patients. The between-group difference and the level of compliance between the CTI and STI was analyzed by t-test and Pearson correlation. The diagnostic value and optimum discriminatory values of the CTI and STI were calculated by a receiver-operating characteristic (ROC) curve and DeLong's test. RESULTS: The distributions of the CTI and STI were similar and showed a slight overlap between the pectus excavatum (PE) and non-PE groups. Both the CTI and STI significantly differed between the 2 groups (P<0.001). The STI demonstrated a strong Pearson correlation with the CTI (r=0.91, 95% confidence interval: 0.88-0.91, P<0.001). The ROC curves showed that STI =1.58 (sensitivity: 0.93, specificity: 0.95) could be considered equivalent to CTI =2.72 (sensitivity: 0.93, specificity: 0.97) as the optimum discriminatory values. DeLong's test showed no significant difference in the ROC curve results between the CTI and STI (Z=0.90, P=0.37). CONCLUSIONS: The STI has comparative discrimination ability in PE diagnosis and deformity severity assessment when used with the standard CTI. The STI as a novel index is not only an ideal evaluation metric of PE deformity but also an objective trait for PE patients just as weight and height for everyone.

18.
J Inorg Biochem ; 224: 111564, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34418715

RESUMO

Bacteria have evolved several outstanding strategies to resist to compounds or factors that compromise their survival. The first line of defense of the cell against environmental stresses is the membrane with fatty acids as fundamental building blocks of phospholipids. In this review, we focus on a periplasmic heme enzyme that catalyzes the cis-trans isomerization of unsaturated fatty acids to trigger a decrease in the fluidity of the membrane in order to rapidly counteract the danger. We particularly detailed the occurrence of such cis-trans isomerase in Nature, the different stresses that are at the origin of the double bond isomerization, the first steps in the elucidation of the mechanism of this peculiar metalloenzyme and some aspects of its regulation.


Assuntos
Bactérias/metabolismo , Grupo dos Citocromos c/metabolismo , Ácidos Graxos Insaturados/metabolismo , Estresse Fisiológico , cis-trans-Isomerases/metabolismo , Heme/metabolismo , Isomerismo , Periplasma/metabolismo , Fosfolipídeos/metabolismo , Temperatura
19.
Heart Rhythm O2 ; 2(3): 255-261, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34337576

RESUMO

BACKGROUND: Patients with typical atrial flutter (AFL) undergoing successful cavotricuspid isthmus ablation remain at risk for future development of new-onset atrial fibrillation (AF). Conventional monitoring (CM) techniques have shown AF incidence rates of 18%-50% in these patients. OBJECTIVES: To evaluate whether continuous monitoring using implantable loop recorders (ILRs) would enhance AF detection in this patient population. METHODS: Veteran patients undergoing AFL ablation between 2002 and 2019 who completed at least 6 months of follow-up after the ablation procedure were included. We compared new-onset AF detection between those who underwent CM and those who received ILRs immediately following AFL ablation. RESULTS: A total of 217 patients (age: 66 ± 9 years; all male) participated. CM was used in 172 (79%) and ILR in 45 (21%) patients. Median follow-up duration after ablation was 4.1 years. Seventy-nine patients (36%) developed new-onset AF, which was detected by CM in 51 and ILR in 28 (30% vs 62%, respectively, P < .001). AF detection occurred at 7.7 months (IQR: 4.7-17.5) after AFL ablation in the ILR group vs 41 months (IQR: 23-72) in the CM group (P < .001). Eleven patients (5%) experienced cerebrovascular events (all in the CM group) and only 4 of these patients (36%) were on long-term anticoagulation. CONCLUSION: Patients undergoing AFL ablation remain at an increased risk of developing new-onset AF, which is detected sooner and more frequently by ILR than by CM. Improving AF detection may allow optimization of rhythm management strategies and anticoagulation in this patient population.

20.
Fa Yi Xue Za Zhi ; 37(2): 215-219, 2021 Apr.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34142483

RESUMO

ABSTRACT: Objective To study the imaging characteristics of maxillary sinus effusion in drowned bodies, to explore its morphological characteristics and value in the diagnosis of the cause of death, and to provide objective evidence to support the study of virtual anatomy of drowning. Methods The 154 postmortem CT examination cases (31 cases of drowning, 123 cases of non-drowning) of Beijing Public Security Bureau Forensic Center in 2019 were collected. The bodies of all cases were scanned by multi-layer spiral CT before double-blind reading by clinical imaging experts. Maxillary sinus of corpses with maxillary sinus effusion in imaging findings was punctured. The detection rate of maxillary sinus effusion was calculated. The CT value and volume of maxillary sinus effusion were measured on 3D DICOM workstation. Results The detection rate of maxillary sinus effusion in the drowning was 100%, the shape was horizontal liquid level, the volume was 1.2-11.2 mL, the CT value was 6.08-19.02 Hu, with an average value of 12.85 Hu. The detection rate of maxillary sinus effusion in non-drowning was 19.51% (24/123), the shape was wavy or irregular, and there were bubbles inside, the volume was 0.4-13.4 mL, the CT value was 23.68-77.75 Hu, with an average value of 42.08 Hu. The differences in CT value between the two groups had statistical significance. Conclusion The postmortem CT examination method can be used to observe the shape and measure the CT value of the maxillary sinus effusion in the bodies in water, which can be an auxiliary examination method for identification of drowning.


Assuntos
Afogamento , Autopsia , Pequim , Afogamento/diagnóstico por imagem , Humanos , Seio Maxilar/diagnóstico por imagem , Tomografia Computadorizada por Raios X
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