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1.
Nat Metab ; 6(7): 1282-1293, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38951660

RESUMO

As the microbiome field moves from descriptive and associative research to mechanistic and interventional studies, being able to account for all confounding variables in the experimental design, which includes the maternal effect1, cage effect2, facility differences3, as well as laboratory and sample handling protocols4, is critical for interpretability of results. Despite significant procedural and bioinformatic improvements, unexplained variability and lack of replicability still occur. One underexplored factor is that the microbiome is dynamic and exhibits diurnal oscillations that can change microbiome composition5-7. In this retrospective analysis of 16S amplicon sequencing studies in male mice, we show that sample collection time affects the conclusions drawn from microbiome studies and its effect size is larger than those of a daily experimental intervention or dietary changes. The timing of divergence of the microbiome composition between experimental and control groups is unique to each experiment. Sample collection times as short as only 4 hours apart can lead to vastly different conclusions. Lack of consistency in the time of sample collection may explain poor cross-study replicability in microbiome research. The impact of diurnal rhythms on the outcomes and study design of other fields is unknown but likely significant.


Assuntos
Microbiota , Animais , Camundongos , Microbiota/genética , Masculino , Manejo de Espécimes/métodos , RNA Ribossômico 16S/genética , Fatores de Tempo , Reprodutibilidade dos Testes , Ritmo Circadiano/fisiologia , Ritmo Circadiano/genética , Estudos Retrospectivos
2.
Eur J Radiol ; 178: 111604, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38996738

RESUMO

PURPOSE: In planning transcatheter aortic valve replacement (TAVR), retrospective cardiac spiral-CT is recommended to measure aortic annulus with subsequent CT-angiography (CTA) to evaluate access routes. Photon-counting detector (PCD)-CT enables to assess the aortic annulus in desired cardiac phases, using prospective ECG-gated high-pitch CTA. The aim of this study was to evaluate the measurement accuracy of aortic annulus using prospective ECG-gated high-pitch CTA against retrospective spiral-CT reference. METHOD: Thirty patients underwent cardiac spiral-CT and prospective ECG-gated (30% R-R on aortic valve level) high-pitch CTA. Using propensity score matching, another 30 patients were identified whose CTA was performed using high-pitch mode without ECG-synchronization. Two investigators measured annular diameter, perimeter, and area on cardiac spiral-CT and high-pitch CTA. RESULTS: The aortic valve was imaged in systole in 90 % of prospective ECG-gated CTA cases but only 50 % of non-ECG-gated CTA cases (p = 0.002). There was a strong correlation (r ≥ 0.94) without significant differences (p ≥ 0.09) between cardiac spiral-CT and prospective ECG-gated high-pitch CTA for all annulus measurements. In contrast, significant differences were found in annular short-axis diameter and area between cardiac spiral-CT and non-ECG-gated high-pitch CTA (p ≤ 0.03). Furthermore, prospective ECG-gated high-pitch CTA showed significantly reduced radiation exposure compared with cardiac spiral-CT (CTDI 4.52 vs. 24.10 mGy; p < 0.001). CONCLUSION: PCD-CT-based prospective ECG-gated high-pitch scans with targeted systolic acquisition at the level of the aortic valve can simultaneously visualize TAVR access routes and accurately measure systolic annulus size. This approach could aid in optimizing protocols to achieve lower radiation doses in the growing population of younger, low-risk TAVR patients.


Assuntos
Valva Aórtica , Técnicas de Imagem de Sincronização Cardíaca , Angiografia por Tomografia Computadorizada , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Masculino , Feminino , Angiografia por Tomografia Computadorizada/métodos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Idoso de 80 Anos ou mais , Idoso , Reprodutibilidade dos Testes , Estudos Prospectivos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Eletrocardiografia , Fótons
3.
Phys Rev Lett ; 132(23): 233001, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905671

RESUMO

Interatomic Coulombic decay (ICD) plays a crucial role in weakly bound complexes exposed to intense or high-energy radiation. So far, neutral or ionic atoms or molecules have been prepared in singly excited electron or hole states that can transfer energy to neighboring centers and cause ionization and radiation damage. Here we demonstrate that a doubly excited atom, despite its extremely short lifetime, can decay by ICD; evidenced by high-resolution photoelectron spectra of He nanodroplets excited to the 2s2p+ state. We find that ICD proceeds by relaxation into excited He^{*}He^{+} atom-pair states, in agreement with calculations. The ability of inducing ICD by resonant excitation far above the single-ionization threshold opens opportunities for controlling radiation damage to a high degree of element specificity and spectral selectivity.

4.
J Chem Phys ; 160(13)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38557851

RESUMO

The dissociative photoionization of phenyl triflate (C6H5OSO2CF3), a neutral photoacid generator used in photolithography, was investigated in a gas phase experiment employing extreme ultraviolet (EUV) synchrotron radiation at 92 eV and photoelectron-photoion coincidence detection. The interaction of EUV photons with the molecule leads almost exclusively to dissociation, which is dominated by a sequential fragmentation mechanism, in which SO2, CF3, CO, and C2H2 are lost. For lithographic purposes, the lack of the observation of a fragment that could serve as a precursor for the formation of triflic acid means that the effective photoacid generator concentration in a photoresist is reduced, impacting its patterning performance in EUV lithography. A better understanding of the dissociative photoionization of photoresist components and proxies thereof can provide a crucial handle that guides the design of photoresists for the upcoming technology nodes with ever decreasing feature sizes for more powerful computer chips.

5.
Gastroenterol. latinoam ; 30(1): 8-12, 2019. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-1103773

RESUMO

Background: Pancreatic fluid collections (PFC) are associated with severe acute pancreatitis. After maturation (after 4 weeks) they are classified as pancreatic pseudocyst (PP) and walled-off necrosis (WON). Endoscopic management is associated with lower morbidity and mortality compared with surgery. Aim: To describe the experience of EUS-guided drainage PFC drainage using plastic stent (PS) or metal stent (lumen apposing metal stents, or "LAMS"). Methods: Retrospective, observational study, between 2016-2019. Results: 17 patients in total. 8 cases were symptomatic PP and 9 were WON. Age 12-72 years. 12 cases in men. Indications: abdominal pain 5 cases and infection 11. The 8 cases of PFC were drained successfully using PS, without adverse effects. Regarding WON drainage, 3 cases were managed with PS and 6 with LAMS. In 5 cases, complementary endoscopic necrosectomy was required. A patient with LAMS required complementary surgical cleaning ("step-up") to treat collections far from the LAMS. Complications: one case of PS presented pigment occlusion with superinfection and another case presented migration to the stomach. Regarding LAMS, one case presented self-limited bleeding, another case presented obstruction of the stent with infection, which was managed endoscopically and with antibiotics. Conclusion: The endoscopic management of PFC is effective and safe, with plastic and metal stent (LAMS). The choice of type of stent depends on the characteristics of PFC (liquid vs solid), center experience and costs.


Introducción: Las colecciones pancreáticas (CP) se asocian a pancreatitis agudas graves. Luego de su maduración (después de las 4 semanas) se clasifican en pseudoquistes (PQ) y necrosis encapsulada (NE). El manejo endoscópico se asocia a menor morbimortalidad comparado con el quirúrgico. Objetivo: Describir la experiencia del drenaje de CP mediante el uso de prótesis plásticas (PP) o metálicas (lumen apposing metal stents, o "LAMS") mediante endosonografía. Método: Estudio retrospectivo, observacional, entre 2016-2018. Resultados: 17 pacientes en total. Ocho casos fueron PQ sintomáticos y 9 NE. Edad 12-72 años (12 casos en hombres). Indicaciones: dolor abdominal 5 casos e infección 11. Los 8 casos de PQ fueron drenados exitosamente con PP, sin efectos adversos. En relación con el drenaje de NE, 3 casos fueron manejados con PP y 6 con LAMS. En 5 casos se requirió necrosectomía endoscópica complementaria. Un paciente con LAMS requirió aseo quirúrgico complementario por colecciones alejadas al LAMS. En relación con las complicaciones, un caso de PP presentó oclusión del pigtail con sobreinfección y otro presentó migración al estómago. Respecto a LAMS, un caso presentó sangrado autolimitado y otro caso obstrucción de la prótesis con sobreinfección, que fue manejada endoscópicamente y con antibióticos. Conclusión: El manejo endoscópico de las CP es efectiva y segura, tanto con prótesis plásticas como metálicas (LAMS). La elección de la prótesis depende de las características de la lesión (líquido vs sólido), experiencia del centro y costos.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Pancreatopatias/cirurgia , Drenagem/métodos , Endoscopia do Sistema Digestório/métodos , Ultrassonografia de Intervenção , Suco Pancreático , Pseudocisto Pancreático , Plásticos , Stents , Drenagem/instrumentação , Estudos Retrospectivos , Metais
6.
Gastroenterol. latinoam ; 28(2): 63-69, 2017. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1118079

RESUMO

BACKGROUND: The use of endoscopic ultrasound with fine needle aspiration (EUS-FNA) has improved the characterization and staging of pancreatic solid masses. The primary strategy for improving the ability to diagnose malignant masses is the use of rapid on site evaluation (ROSE) by a cytopathologist. OBJECTIVE: To evaluate the diagnostic yield of EUS-FNA after the implementation of ROSE in an academic center. MATERIAL AND METHODS: Prospective enrollment and follow-up of EUS-FNA with ROSE during 2015 and 2016, was compared to EUS-FNA without ROSE in previous years (2011-2014) in Hospital Clínico UCChristus. Clinical and endosonographic features, cytopathological and histological diagnosis and number of passes per procedure were evaluated. All EUS-FNA included cytology and cellular block for definitive diagnosis. RESULTS: 59 pancreatic solid masses were included in the analysis. 44 EUS-FNA were performed with ROSE, compared with 15 EUS-FNA without ROSE. The mean age of patients included was 62.8 years, 54.2% male gender, and most masses studied were in the head of pancreas (77.6%). In EUS 86.5% were hypoechoic and 56.9% had poor defined margins. No differences in baseline characteristics were observed between groups. EUS-FNA led to diagnosis in 86.2% of the overall sample. The diagnostic rate was superior in the group of EUS-FNA with ROSE, compared to EUS-FNA without ROSE (97.7% vs 50%, p < 0.0001). The mean number of passes was inferior in EUS-FNA ROSE (+) (2.71 vs 5.78, p < 0.0001). No differences in rate of complications were observed between groups. CONCLUSION: The use of ROSE associated to EUS-FNA improves the diagnostic yield in the evaluation of pancreatic solid masses. Our findings are consistent with those described in the literature, recommending the use of ROSE in EUS-FNA in centers where the diagnostic yield is less than 90% without the use of ROSE


INTRODUCCIÓN: La adquisición de tejido mediante el uso de endosonografía, con punción con aguja fina, (EUS-FNA) ha mejorado el diagnóstico de lesiones pancreáticas sólidas. La principal medida para aumentar el rendimiento diagnóstico de la EUS-FNA es la evaluación por citopatólogo próximo al lugar de punción (in situ) (técnica conocida en inglés como ROSE "rapid on-site evaluation"). OBJETIVO: Evaluar el rendimiento diagnóstico de EUS-FNA en lesiones pancreáticas sólidas posterior a la implementación de ROSE en un centro universitario. MATERIAL Y MÉTODOS: Registro prospectivo de EUS-FNA realizadas con ROSE durante el período 2015-2016, comparado con EUS-FNA con evaluación histopatológica diferida realizada entre los años 2011-2014, en Hospital Clínico UC-Christus. Se evaluaron características clínicas, endosonográficas, diagnóstico histopatológico y número de pases por procedimiento. Todas las EUS-FNA incluyeron citología y block celular para diagnóstico definitivo. RESULTADOS: Se incluyeron en el análisis 59 lesiones pancreáticas sólidas evaluadas con EUS-FNA. Seguimiento prospectivo de 44 EUS-FNA con ROSE, que fueron comparadas con 15 EUS-FNA sin evaluación in situ (retrospectivo). La muestra total incluyó individuos con un promedio de 62,8 años de edad, 54,2% hombres, donde 77,6% de las lesiones se ubicaba en la cabeza pancreática. Endosonográficamente 86,5% de las lesiones eran hipoecoicas y 56,9% tenían márgenes poco definidos. La EUS-FNA fue diagnóstica en 86,2% del total de la muestra. Las EUS-FNA realizadas con ROSE presentaron un mayor rendimiento diagnóstico respecto a las efectuadas sin evaluación in situ (97,7% vs 50%, p < 0,0001). El número de pases por procedimiento fue menor (2,7% vs 5,8%, p < 0,0001) en el grupo con ROSE. No hubo diferencias en complicaciones en ambos grupos. CONCLUSIÓN: La evaluación por citopatólogo in situ de la muestra obtenida por EUS-FNA mejora el rendimiento diagnóstico de las lesiones pancreáticas sólidas. Nuestros hallazgos apoyan el uso de ROSE asociado a EUS-FNA, siendo concordantes con las recomendaciones actuales de utilizar evaluación histopatológica in situ en EUS-FNA, especialmente en centros donde el rendimiento diagnóstico sin uso de ROSE es menor a 90%.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Pancreatopatias/patologia , Pancreatopatias/diagnóstico por imagem , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/diagnóstico por imagem , Estudos Prospectivos , Seguimentos , Biópsia por Agulha Fina , Avaliação Rápida da Integridade Ambiental
8.
Arq. bras. med. vet. zootec ; 61(6): 1275-1280, dez. 2009. ilus
Artigo em Português | LILACS | ID: lil-537251

RESUMO

Realizou-se uma série de biópsias cardíacas em cães para testar o acesso toracoscópico, utilizando-se oito cães sem raça definida, sob condições de manejo e alimentação adequados. A abordagem à cavidade torácica foi feita por meio de cirurgia torácica videoassistida e o instrumental utilizado para remoção do fragmento de miocárdio foi o convencional em lugar das pinças de videocirurgia. A eficácia do procedimento foi confirmada pelo tempo decorrido entre as incisões, a execução da biópsia e a sutura do tórax, com duração média de 15 minutos. A cirurgia torácica videoassistida para biópsias cardíacas foi considerada segura e adequada, minimizando o desconforto pós-operatório dos pacientes submetidos ao acesso torácico.


In order to evaluate the thoracoscopy access, biopsies were carried out in eight mongrel dogs maintained under appropriate conditions of handling and feeding. The patients were prepared to aseptic and atraumatic surgery approaching the thoracic cavity by means of video-assisted thoracic surgery (VATS). Myocardial biopsies were carried out with conventional surgical instruments as an alternative to the clamps of video surgery. The effectiveness of the procedure was confirmed by mean time (15 minutes) elapsed from thoracic approach and biopsies obtainment to thoracic wall suture. VATS is a secure and appropriate technique to carry out myocardial biopsies that minimize postoperative discomfort in patients submitted to thoracic approach.


Assuntos
Animais , Cães , Biópsia , Cirurgia Torácica/métodos , Procedimentos Cirúrgicos Cardíacos/métodos , Cirurgia Torácica Vídeoassistida , Cicatriz , Miocárdio/patologia , Tórax/patologia
12.
Int. j. lepr ; 26(2): 134-143, Apr.Jun. 1958. map, tab, graf
Artigo em Inglês | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1227830

RESUMO

A review of epidemiologic data on leprosy in Turkey is presented, and the findings in 229 patients which we examined in the leprosarium in Elazig province are discussed. The problems of the endemicity of the disease in Turkey are discussed, and methods to combat it are suggested.


Assuntos
Hanseníase , Hanseníase/classificação , Hanseníase/complicações , Hanseníase/diagnóstico , Hanseníase/etnologia
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