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1.
Radiology ; 311(3): e231598, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38916502

RESUMO

Background Photon-counting CT (PCCT) represents a recent advancement in CT, offering improved spatial resolution and spectral separability. By using multiple adjustable energy bins, PCCT enables K-edge imaging, allowing mixed contrast agent distinction. Deep-silicon is a new type of photon-counting detector with different characteristics compared with cadmium photon-counting detectors. Purpose To evaluate the performance of a prototype deep-Si PCCT scanner and compare it with that of a state-of-the-art dual-energy energy-integrating detector (EID) scanner in imaging coronary artery plaques enhanced with iodine and K-edge contrast agents. Materials and Methods A series of 10 three-dimensional-printed inserts (diameter, 3.5 mm) was prepared, and materials mimicking soft and calcified plaques were added to simulate stenosed coronary arteries. Inserts filled with an iodine- or gadolinium-based contrast agent (GBCA) were scanned. Virtual monoenergetic images (VMIs) and iodine maps were generated using two- and eight-energy bin data from EID CT and PCCT, respectively. Gadolinium maps were calculated for PCCT. The CT numbers of VMIs and iodine maps were compared. Spatial resolution and blooming artifacts were compared on the 70-keV VMIs in plaque-free and calcified coronary arteries. Results No evidence of a significant difference in the CT number of 70-keV images was found except in inserts containing GBCAs. In the absence of a GBCA, excellent (r > 0.99) agreement for iodine was found. PCCT could quantify the GBCA within 0.2 mg Gd/mL ± 0.8 accuracy of the ground truth, whereas EID CT failed to detect the GBCA. Lumen measurements were more accurate for PCCT than for EID CT, with mean errors of 167 versus 442 µm (P < .001) compared with the 3.5-mm ground truth. Conclusion Deep-Si PCCT demonstrated good accuracy in iodine quantification and could accurately decompose mixtures of two contrast agents. Its improved spatial resolution resulted in sharper images with blooming artifacts reduced by 50% compared with a state-of-the-art dual-energy EID CT scanner. © RSNA, 2024.


Assuntos
Meios de Contraste , Imagens de Fantasmas , Fótons , Humanos , Tomografia Computadorizada por Raios X/métodos , Vasos Coronários/diagnóstico por imagem , Silício , Desenho de Equipamento
2.
Europace ; 26(9)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39210643

RESUMO

AIMS: The extravascular implantable cardioverter-defibrillator (EV ICD) has been shown to be safe and effective for patients at risk of sudden cardiac death, but little is known about EV ICD lead removal in humans. This analysis aimed to characterize the EV ICD lead removal experience thus far. METHODS AND RESULTS: This was a retrospective analysis of lead removals from the EV ICD Pilot, Pivotal, and Continued Access Studies. Patients with a successful EV ICD implant who underwent lead removal were included. The main objective was lead removal success. Ancillary objectives included characterizing technique used, procedure complications, and reimplantation status. An EV ICD system was successfully implanted in 347 patients across the 3 studies (25.9% female; 53.4 ± 13.3 years; left ventricular ejection fraction: 39.7 ± 15.9). Of these patients, 29 (8.4%) underwent lead removal with a mean lead dwell time of 12.6 ± 14.3 months (0.2-58.4). The main reason for lead removal was lead dislodgement (n = 9, 31.0%). Lead removal was successful in 27/29 (93.1%) cases [100% (19/19) success rate <1 year and 80% (8/10) success rate >1 year post-implant]. Simple traction was used in 22/26 (84.6%) and extraction tools in 4/26 (15.4%) successful cases where technique was known. No complications were reported for any of the removal procedures. All 11 EV ICD reimplant attempts were successful. CONCLUSION: Complete removal of the EV ICD lead was successful in 93.1% of cases, and simple traction was sufficient in most instances. Based on these results, lead removal from the substernal space was safe and achievable up to 3 years post-implant.


Assuntos
Desfibriladores Implantáveis , Remoção de Dispositivo , Humanos , Remoção de Dispositivo/métodos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Retrospectivos , Idoso , Adulto , Resultado do Tratamento , Morte Súbita Cardíaca/prevenção & controle , Morte Súbita Cardíaca/etiologia , Projetos Piloto , Fatores de Tempo , Cardioversão Elétrica/instrumentação , Cardioversão Elétrica/efeitos adversos
3.
Regul Toxicol Pharmacol ; 146: 105517, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37838350

RESUMO

Currently there are three test guidelines (TG) for acute oral toxicity studies of substances or mixtures from the Organisation for Economic Co-operation and Development (OECD). TG 423 and TG 425 use lethality as an endpoint, while TG 420 replaces death with 'evident toxicity', defined as clear signs that exposure to a higher dose would result in death. However, the perceived subjectivity of 'evident toxicity' may be preventing wider use of TG 420. To address this, the UK National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) and the European Partnership for Alternative Approaches to Animal Testing (EPAA) collaborated to provide recommendations on the recognition of 'evident toxicity'. Historical data from acute oral toxicity studies were analysed for clinical signs at the lower dose that could have predicted death at the higher dose. Several signs including ataxia, laboured respiration, and eyes partially closed, alone or in combination, are highly predictive. Others such as lethargy, decreased respiration, and loose faeces have lower but still appreciable positive predictive value (PPV). The data has been used to develop recommendations to promote use of TG 420 and thus reduce the suffering and numbers of animals used in acute oral toxicity studies.


Assuntos
Diarreia , Organização para a Cooperação e Desenvolvimento Econômico , Animais , Testes de Toxicidade Aguda
4.
Clin Infect Dis ; 77(8): 1194-1200, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37309679

RESUMO

BACKGROUND: Kidney failure is an established risk factor for tuberculosis (TB), but little is known about TB risk in people with chronic kidney disease (CKD) who have not initiated kidney replacement therapy (CKD without kidney failure). Our primary objective was to estimate the pooled relative risk of TB disease in people with CKD stages 3-5 without kidney failure compared with people without CKD. Our secondary objectives were to estimate the pooled relative risk of TB disease for all stages of CKD without kidney failure (stages 1-5) and by each CKD stage. METHODS: This review was prospectively registered (PROSPERO CRD42022342499). We systematically searched MEDLINE, Embase, and Cochrane databases for studies published between 1970 and 2022. We included original observational research estimating TB risk among people with CKD without kidney failure. Random-effects meta-analysis was performed to obtain the pooled relative risk. RESULTS: Of the 6915 unique articles identified, data from 5 studies were included. The estimated pooled risk of TB was 57% higher in people with CKD stages 3-5 than in people without CKD (adjusted hazard ratio: 1.57; 95% CI: 1.22-2.03; I2 = 88%). When stratified by CKD stage, the pooled rate of TB was highest in stages 4-5 (incidence rate ratio: 3.63; 95% CI: 2.25-5.86; I2 = 89%). CONCLUSIONS: People with CKD without kidney failure have an increased relative risk of TB. Further research and modeling are required to understand the risks, benefits, and CKD cutoffs for screening people for TB with CKD prior to kidney replacement therapy.


Assuntos
Falência Renal Crônica , Insuficiência Renal Crônica , Tuberculose , Humanos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia , Tuberculose/complicações , Tuberculose/epidemiologia , Terapia de Substituição Renal , Fatores de Risco , Falência Renal Crônica/complicações
5.
Glob Chang Biol ; 29(12): 3318-3330, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37020174

RESUMO

Scientists and managers rely on indicator taxa such as coral and macroalgal cover to evaluate the effects of human disturbance on coral reefs, often assuming a universally positive relationship between local human disturbance and macroalgae. Despite evidence that macroalgae respond to local stressors in diverse ways, there have been few efforts to evaluate relationships between specific macroalgae taxa and local human-driven disturbance. Using genus-level monitoring data from 1205 sites in the Indian and Pacific Oceans, we assess whether macroalgae percent cover correlates with local human disturbance while accounting for factors that could obscure or confound relationships. Assessing macroalgae at genus level revealed that no genera were positively correlated with all human disturbance metrics. Instead, we found relationships between the division or genera of algae and specific human disturbances that were not detectable when pooling taxa into a single functional category, which is common to many analyses. The convention to use percent cover of macroalgae as an indication of local human disturbance therefore likely obscures signatures of local anthropogenic threats to reefs. Our limited understanding of relationships between human disturbance, macroalgae taxa, and their responses to human disturbances impedes the ability to diagnose and respond appropriately to these threats.


Assuntos
Antozoários , Alga Marinha , Animais , Humanos , Recifes de Corais , Ecossistema , Alga Marinha/fisiologia , Antozoários/fisiologia , Oceano Pacífico
6.
Circ J ; 87(12): 1809-1816, 2023 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-37532552

RESUMO

BACKGROUND: The Micra leadless pacemaker has demonstrated favorable outcomes in global trials, but its real-world performance and safety in a Japan-specific population is unknown.Methods and Results: Micra Acute Performance (MAP) Japan enrolled 300 patients undergoing Micra VR leadless pacemaker implantation in 15 centers. The primary endpoint was the acute (30-day) major complication rate. The 30-day and 6-month major complication rates were compared to global Micra studies. All patients underwent successful implantation with an average follow-up of 7.23±2.83 months. Compared with previous Micra studies, Japanese patients were older, smaller, more frequently female, and had a higher pericardial effusion risk score. 11 acute major complications were reported in 10 patients for an acute complication rate of 3.33% (95% confidence interval: 1.61-6.04%), which was in line with global Micra trials. Pericardial effusion occurred in 4 patients (1.33%; 3 major, 1 minor). No procedure or device-related deaths occurred. Frailty significantly improved from baseline to follow-up as assessed by Japan Cardiovascular Health Study criteria. CONCLUSIONS: In a Japanese cohort, implantation of the Micra leadless pacemaker had a high success rate and low major complication rate. Despite the Japan cohort being older, smaller, and at higher risk, the safety and performance was in line with global Micra trials.


Assuntos
Arritmias Cardíacas , Marca-Passo Artificial , Feminino , Humanos , População do Leste Asiático , Desenho de Equipamento , Marca-Passo Artificial/efeitos adversos , Derrame Pericárdico/etiologia , Resultado do Tratamento , Masculino , Arritmias Cardíacas/terapia
7.
Conserv Biol ; 36(2): e13807, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34312893

RESUMO

Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations.


Las pesquerías marinas de los ecosistemas costeros en muchas áreas del mundo históricamente han removido a individuos de gran tamaño, potencialmente perjudicando el funcionamiento ambiental y la sostenibilidad a largo plazo de las poblaciones de peces. Los reportes sobre los indicadores basados en el tamaño que se vinculan con la estructura de la red alimenticia pueden contribuir al manejo basado en el ecosistema, aunque la aplicación de estos indicadores a grandes (inter-ecosistemas) escalas geográficas ha estado limitada a datos de captura dependientes de las pesquerías o métodos basados en el buceo restringidos a aguas someras (<20 m), lo cual puede representar erróneamente la abundancia de peces de gran tamaño capturados para la pesca. Obtuvimos los datos de la estructura del tamaño corporal de 82 teleósteos marinos demersales focalizados por razones recreativas o comerciales tomados de 2,904 despliegues de video estéreo subacuático remoto con cebo (stereo-BRUV, en inglés). El muestreo se realizó hasta los 50 metros de profundidad y abarcó aproximadamente 10,000 km del talud continental de Australia. El relieve marino, la profundidad del agua y la gravedad humana (es decir, un indicador de los impactos humanos) fueron los pronosticadores más sólidos de la probabilidad de incidencia de los peces de gran tamaño y de la abundancia de peces por encima del tamaño legal mínimo de captura. Las reservas marinas de protección total tienen un efecto positivo sobre la abundancia de los peces que están por encima del tamaño legal, aunque el efecto varió según el grupo de especies. Como contraste, los peces de tamaño sublegal fueron pronosticados de mejor manera usando gradientes de la temperatura de la superficie marina (media y varianza). En las áreas con un impacto humano reducido, los peces de gran tamaño corporal tenían hasta tres veces mayor probabilidad de aparecer y los peces de tamaño legal eran aproximadamente cinco veces más abundantes. Para los grupos de especies conspicuas con afinidades contrastantes de hábitat, ambiente y biogeografía, la abundancia de peces de tamaño legal normalmente declinó conforme aumentó el impacto humano. Nuestros análisis cuantitativos a gran escala resaltan la importancia conjunta que tienen la complejidad marina, las regiones con una huella humana reducida y las reservas marinas de protección total para la protección de los peces de gran tamaño corporal en una extensa gama de especies y configuraciones ecosistémicas. Efectos de la Huella Humana y los Factores Biofísicos sobre la Estructura del Tamaño Corporal de Especies Marinas Capturadas para la Pesca.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Austrália , Tamanho Corporal , Pesqueiros , Peixes , Humanos
8.
Am J Otolaryngol ; 43(1): 103227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34563805

RESUMO

BACKGROUND: Chronic rhinosinusitis (CRS) in the setting of Aspirin Exacerbated Respiratory Disease (AERD) have high rate of treatment failure and disease recurrence. OBJECTIVE: Evaluate the long-term effect of zileuton on sinonasal outcomes in patients with AERD. METHODS: AERD patients were reviewed and divided into two cohorts, depending if they were treated with zileuton during their clinical course. Demographic data, 22-item sinonasal outcome test (SNOT-22), Lund-Kennedy (LK) endoscopy score, duration of treatment, and number of sinus surgeries performed were collected. RESULTS: 40 AERD patients were included, with follow-up duration up to 10 years (avg of 5.2 years). All patients were treated with topical saline and budesonide irrigations, intranasal steroid spray, and montelukast. 19 patients had uncontrolled sinus disease requiring multiple steroid tapers and were switched from montelukast to zileuton (cohort 1, 47.5%) at some point in their treatment. 21 patients (cohort 2, 52.5%) never needed zileuton. The average duration of treatment with zileuton was 6 years. Patients who required zileuton had a worse SNOT-22 (32.1 vs 19, p = 0.117), worse LK score (8.1 vs 7.5, p = 0.504), and higher average number of surgeries (1.9 vs 1.6, p = 0.343). The outcomes in the zileuton cohort trended toward improvement, however these did not reach statistical significance with an improved SNOT-22 from 32.1 to 27.4 (p = 0.617) and LK score from 7.9 to 6.2 (p = 0.092); The addition of zileuton significantly lowered the number of surgeries needed to an average of 0.5 (p < 0.0001). CONCLUSION: Zileuton may help decrease the number of sinus surgeries needed in AERD.


Assuntos
Asma Induzida por Aspirina/tratamento farmacológico , Hidroxiureia/análogos & derivados , Antagonistas de Leucotrienos/uso terapêutico , Rinite/tratamento farmacológico , Sinusite/tratamento farmacológico , Adulto , Idoso , Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/efeitos adversos , Asma Induzida por Aspirina/complicações , Doença Crônica , Feminino , Humanos , Hidroxiureia/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Rinite/induzido quimicamente , Índice de Gravidade de Doença , Sinusite/induzido quimicamente , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
Carcinogenesis ; 42(2): 232-242, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32816038

RESUMO

More than a million cases of cutaneous squamous cell carcinoma are diagnosed in the USA each year, and its incidence is increasing. Most of these malignancies arise from premalignant lesions, providing an opportunity for intervention before malignant progression. We previously documented how cytoplasmic mislocalization of CDC25A in premalignant and malignant skin cancers confers resistance to apoptotic cell death via a mechanism that depends on its interaction with 14-3-3ε. From these data, we hypothesized that 14-3-3ε overexpression drives skin tumor development and progression, such that targeting 14-3-3ε may be a useful strategy for skin cancer treatment. Like CDC25A, 14-3-3ε was overexpressed and mislocalized to the cytoplasm of both benign and malignant human skin cancer. Skin-targeted deletion of the 14-3-3ε gene reduced skin tumor development by 75% and blocked malignant progression. 14-3-3ε suppressed apoptosis through activation of Akt, leading to inhibition of BCL2 associated agonist of cell death and upregulation of Survivin. Using virtual tetrapeptide libraries, we developed a novel peptide that specifically blocked 14-3-3ε heterodimerization and thereby prevented its interaction with CDC25A. The peptide reduced prosurvival signaling, killed skin cancer cells and reduced skin tumor growth in xenograft. Normal skin keratinocytes were unaffected by inhibition or deletion of 14-3-3ε. Thus, targeting of 14-3-3ε dimerization is a promising strategy for the treatment of premalignant skin lesions.


Assuntos
Proteínas 14-3-3/antagonistas & inibidores , Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Fosfatases cdc25/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , 9,10-Dimetil-1,2-benzantraceno/administração & dosagem , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Carcinógenos/administração & dosagem , Carcinógenos/toxicidade , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Feminino , Humanos , Queratinócitos , Masculino , Camundongos , Camundongos Knockout , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Multimerização Proteica/efeitos dos fármacos , Neoplasias Cutâneas/patologia , Acetato de Tetradecanoilforbol/administração & dosagem , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/toxicidade , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Glob Chang Biol ; 27(15): 3432-3447, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34015863

RESUMO

Marine reserves are a key tool for the conservation of marine biodiversity, yet only ~2.5% of the world's oceans are protected. The integration of marine reserves into connected networks representing all habitats has been encouraged by international agreements, yet the benefits of this design has not been tested empirically. Australia has one of the largest systems of marine reserves, providing a rare opportunity to assess how connectivity influences conservation success. An Australia-wide dataset was collected using baited remote underwater video systems deployed across a depth range from 0 to 100 m to assess the effectiveness of marine reserves for protecting teleosts subject to commercial and recreational fishing. A meta-analytical comparison of 73 fished species within 91 marine reserves found that, on average, marine reserves had 28% greater abundance and 53% greater biomass of fished species compared to adjacent areas open to fishing. However, benefits of protection were not observed across all reserves (heterogeneity), so full subsets generalized additive modelling was used to consider factors that influence marine reserve effectiveness, including distance-based and ecological metrics of connectivity among reserves. Our results suggest that increased connectivity and depth improve the aforementioned marine reserve benefits and that these factors should be considered to optimize such benefits over time. We provide important guidance on factors to consider when implementing marine reserves for the purpose of increasing the abundance and size of fished species, given the expected increase in coverage globally. We show that marine reserves that are highly protected (no-take) and designed to optimize connectivity, size and depth range can provide an effective conservation strategy for fished species in temperate and tropical waters within an overarching marine biodiversity conservation framework.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Austrália , Ecossistema , Pesqueiros , Peixes , Oceanos e Mares
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