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1.
Hum Fertil (Camb) ; 27(1): 2310639, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38346450

RESUMO

There is a need to understand teenagers' views towards having children to better tailor sexuality and reproductive health education. We conducted a survey of parenthood intentions for 16-18-year-old students. The survey was anonymous, contained open-ended and multiple-choice questions and was live from 10 May 2021 to 18 July 2022. The sample size was n = 931. Quantitative data were analysed descriptively and using chi-squared tests; qualitative data were analysed thematically. The majority of students (64%) indicated they wanted to have children in the future, with 49% desiring to have two children. Students who opted against having children cited the turbulent state of the world, concerns about parenthood, and, for many females, negative associations to pregnancy and childbirth. Many students felt concern about the possibility of having children in the future (45%), expressing concerns about their ability to have healthy children and worries about the lives their children might lead. Six themes were identified in their responses to the question 'What are your concerns about the possibility of having children in the future?': Fears; Self-doubt; Health and wellbeing; Big investment; Hinderance to personal aspirations; and Non-inclusive LGBTQ+ education. We conclude by making recommendations as to how school reproductive health and sex education might be improved.


Assuntos
Fertilidade , Intenção , Gravidez , Feminino , Adolescente , Criança , Humanos , Conhecimentos, Atitudes e Prática em Saúde , Serviços de Planejamento Familiar , Estudantes
2.
Adv Sci (Weinh) ; 11(9): e2306087, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38115760

RESUMO

Major biological discoveries are made by interrogating living organisms with light. However, the limited penetration of un-scattered photons within biological tissues limits the depth range covered by optical methods. Deep-tissue imaging is achieved by combining light and ultrasound. Optoacoustic imaging exploits the optical generation of ultrasound to render high-resolution images at depths unattainable with optical microscopy. Recently, laser ultrasound has been suggested as a means of generating broadband acoustic waves for high-resolution pulse-echo ultrasound imaging. Herein, an approach is proposed to simultaneously interrogate biological tissues with light and ultrasound based on layer-by-layer coating of silica optical fibers with a controlled degree of transparency. The time separation between optoacoustic and ultrasound signals collected with a custom-made spherical array transducer is exploited for simultaneous 3D optoacoustic and laser ultrasound (OPLUS) imaging with a single laser pulse. OPLUS is shown to enable large-scale anatomical characterization of tissues along with functional multi-spectral imaging of chromophores and assessment of cardiac dynamics at ultrafast rates only limited by the pulse repetition frequency of the laser. The suggested approach provides a flexible and scalable means for developing a new generation of systems synergistically combining the powerful capabilities of optoacoustics and ultrasound imaging in biology and medicine.


Assuntos
Lasers , Microscopia , Ultrassonografia
3.
Nutrients ; 15(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37960169

RESUMO

To understand the extent to which different sources of diet and nutrition information are sought, trusted, and relied upon for making dietary changes, the present international web-based survey study gauged participants' (n = 3419) diet-nutrition information-seeking behaviors from 22 interpersonal and general sources with varying quality, trust levels in these sources, and reliance on each source for making dietary changes. Qualitative insights were also captured regarding trustworthiness formation. The results revealed a disconnect between source popularity and perceived trustworthiness. While nutrition-health websites, Google-Internet searches, and diet-health books were most commonly consulted, participants placed the highest level of trust in nutrition scientists, nutrition professionals, and scientific journals, suggesting that frequent information seeking from a subpar source may not be a reliable predictor of the level of trust assigned to it. Although the frequency of source-seeking behaviors and source trustworthiness both contributed to dietary changes, the latter appeared to have a more pronounced influence. When a source was less trusted, there was a reduced likelihood of relying on it for changing diet. Additionally, source seeking may not always translate into effective dietary change, as shown by the less strong correlation between the two. These associations significantly differed depending on the source.


Assuntos
Dieta , Comportamento de Busca de Informação , Humanos , Inquéritos e Questionários , Estado Nutricional , Comportamento Alimentar , Internet
4.
Hum Fertil (Camb) ; 26(3): 527-539, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37356204

RESUMO

Reproductive health education is crucial to ensure young people understand their reproductive system and can make informed decisions about their sexual lives and fertility, including whether they want to have children or not. This study involved an investigation of the intended UK school curricula for 14-18 year-olds as they relate to reproductive health. Analysis revealed substantial differences. Most, but not all, specifications include sexually transmitted infections, hormonal aspects of reproduction, contraception, the menstrual cycle and assisted reproductive technology (ART). Important topics, such as endometriosis, fertility, preconception health, pregnancy, miscarriage, menopause and infertility (except in the context of ART) are missing from examination specifications and/or the RSE/RSHP curricula. We conclude that many young people in the UK are at risk of leaving school with inadequate understanding of concepts that have important implications for their reproductive health. There are differences between nations, with Scotland having the most comprehensive coverage of topics in its curriculum. High-quality reproductive health education should be an entitlement for all young people. It should give young people accurate and up-to-date information and enable them to discuss issues and develop their own thinking. Ideally, sex and reproductive health education would be taught comprehensively across the RSE/RSHP and science curricula.

5.
Cult Stud Sci Educ ; : 1-19, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37360053

RESUMO

There has been little consideration in the science education literature of schools or curricula that advocate creationism. Accelerated Christian Education (ACE) is among the world's largest providers of creationist science materials with a curriculum divided into a system of workbooks which students complete at their own speed. This article examines the ways in which ACE presents particular areas of science that it considers to be contentious, namely evolution and climate change. The ACE curriculum has recently been rewritten, and we show that, like previous editions, the current curriculum relies on rote memorisation to the exclusion of other styles of learning, and that information presented is often misleading or distorted. Religious explanations of natural phenomena are sometimes given in place of scientific ones, and creationist assumptions are inserted into lessons not directly related to evolution or the Big Bang. Those who reject creationism are depicted as making an immoral choice. ACE's recent curricula also add material denying the role of humans in climate change. It is argued that both the teaching methods and content of the ACE curriculum place students at an educational disadvantage.

6.
Photoacoustics ; 31: 100508, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37228577

RESUMO

High-intensity focused ultrasound (HIFU) enables localized ablation of biological tissues by capitalizing on the synergistic effects of heating and cavitation. Monitoring of those effects is essential for improving the efficacy and safety of HIFU interventions. Herein, we suggest a hybrid optoacoustic-ultrasound (OPUS) approach for real-time assessment of heating and cavitation processes while providing an essential anatomical reference for accurate localization of the HIFU-induced lesion. Both effects could clearly be observed by exploiting the temperature dependence of optoacoustic (OA) signals and the strong contrast of gas bubbles in pulse-echo ultrasound (US) images. The differences in temperature increase and its rate, as recorded with a thermal camera for different HIFU pressures, evinced the onset of cavitation at the expected pressure threshold. The estimated temperatures based on OA signal variations were also within 10-20 % agreement with the camera readings for temperatures below the coagulation threshold (∼50 °C). Experiments performed in excised tissues as well as in a post-mortem mouse demonstrate that both heating and cavitation effects can be effectively visualized and tracked using the OPUS approach. The good sensitivity of the suggested method for HIFU monitoring purposes was manifested by a significant increase in contrast-to-noise ratio within the ablated region by > 10 dB and > 5 dB for the OA and US images, respectively. The hybrid OPUS-based monitoring approach offers the ease of handheld operation thus can readily be implemented in a bedside setting to benefit several types of HIFU treatments used in the clinics.

7.
Nat Protoc ; 18(7): 2124-2142, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37208409

RESUMO

Fast tracking of biological dynamics across multiple murine organs using the currently commercially available whole-body preclinical imaging systems is hindered by their limited contrast, sensitivity and spatial or temporal resolution. Spiral volumetric optoacoustic tomography (SVOT) provides optical contrast, with an unprecedented level of spatial and temporal resolution, by rapidly scanning a mouse using spherical arrays, thus overcoming the current limitations in whole-body imaging. The method enables the visualization of deep-seated structures in living mammalian tissues in the near-infrared spectral window, while further providing unrivalled image quality and rich spectroscopic optical contrast. Here, we describe the detailed procedures for SVOT imaging of mice and provide specific details on how to implement a SVOT system, including component selection, system arrangement and alignment, as well as the image processing methods. The step-by-step guide for the rapid panoramic (360°) head-to-tail whole-body imaging of a mouse includes the rapid visualization of contrast agent perfusion and biodistribution. The isotropic spatial resolution possible with SVOT can reach 90 µm in 3D, while alternative steps enable whole-body scans in less than 2 s, unattainable with other preclinical imaging modalities. The method further allows the real-time (100 frames per second) imaging of biodynamics at the whole-organ level. The multiscale imaging capacity provided by SVOT can be used for visualizing rapid biodynamics, monitoring responses to treatments and stimuli, tracking perfusion, and quantifying total body accumulation and clearance dynamics of molecular agents and drugs. Depending on the imaging procedure, the protocol requires 1-2 h to complete by users trained in animal handling and biomedical imaging.


Assuntos
Processamento de Imagem Assistida por Computador , Técnicas Fotoacústicas , Tomografia Computadorizada de Feixe Cônico Espiral , Animais , Camundongos , Perfusão , Técnicas Fotoacústicas/métodos , Distribuição Tecidual , Tomografia Computadorizada de Feixe Cônico Espiral/métodos , Modelos Animais de Doenças , Meios de Contraste
8.
Photoacoustics ; 30: 100480, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37025111

RESUMO

Optoacoustic tomography has been established as a powerful modality for preclinical imaging. However, efficient whole-body imaging coverage has not been achieved owing to the arduous requirement for continuous acoustic coupling around the animal. In this work, we introduce panoramic (3600) head-to-tail 3D imaging of mice with spiral volumetric optoacoustic tomography (SVOT). The system combines multi-beam illumination and a dedicated head holder enabling uninterrupted acoustic coupling for whole-body scans. Image fidelity is optimized with self-gated respiratory motion rejection and dual speed-of-sound reconstruction algorithms to attain spatial resolution down to 90 µm. The developed system is thus highly suitable for visualizing rapid biodynamics across scales, such as hemodynamic changes in individual organs, responses to treatments and stimuli, perfusion, total body accumulation, or clearance of molecular agents and drugs with unmatched contrast, spatial and temporal resolution.

9.
BMJ Open ; 13(4): e073224, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-37015797

RESUMO

OBJECTIVES: Patient-centred care has been raised as an important component in providing high-quality healthcare services. This research aims to measure physicians' attitudes towards patient-centred care in Chinese healthcare settings and to identify the sociodemographic predictors of their attitudes using an exploratory research design. DESIGN: A cross-sectional survey. SETTING: Twelve hospitals in Beijing, China. PARTICIPANTS: 1290 physicians from 12 hospitals in Beijing were invited to take part in the survey using snowball sampling methods. There was a response rate of 84% (n=1084), of which 1053 responses (82%) were valid and included in this research. METHODS: This research used a survey containing a previously validated 6-point Likert scale called 'Chinese-revised Patient-Practitioner Orientation Scale' (CR-PPOS). Descriptive statistics and multivariable logistic regression analyses were performed to measure participants' attitudes and to identify the sociodemographic predictors of Chinese physicians' attitudes towards patient-centred care. RESULTS: Gender, professional title (ie, seniority) and hospital type influence Chinese physicians' attitudes towards patient-centred care. Female physicians, physicians with intermediate titles and those who work in tertiary (ie, top-level) hospitals tend to have higher patient-centred attitudes (OR=1.532, 95% CI 1.160 to 2.022; OR=2.089, 95% CI 1.206 to 3.618; OR=2.198, 95% CI 1.465 to 3.297) than male physicians with other titles, and than those who work in first, secondary or private hospitals. Physicians working in non-surgical departments, those who have received training in doctor-patient communication, and those who are satisfied with their income obtained high patient-centred scores, both on the overall CR-PPOS and its two subscales. CONCLUSIONS: This research identified sociodemographic predictors of Chinese physicians' attitudes towards patient-centred care. The findings contribute to knowledge of factors to be considered in reforming medical education and the Chinese healthcare system to improve physician-patient relationships and provide high-quality healthcare to patients. However, these findings are exploratory in nature and require further investigation to establish their validity and generalisability.


Assuntos
Atitude do Pessoal de Saúde , Médicos , Humanos , Masculino , Feminino , Estudos Transversais , Assistência Centrada no Paciente , Relações Médico-Paciente , Inquéritos e Questionários
10.
Lancet ; 401(10381): 985-986, 2023 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-36966747
11.
Nutrients ; 15(2)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36678321

RESUMO

To understand the susceptibility to nutrition-health misinformation related to preventing, treating, or mitigating the risk of COVID-19 during the initial lockdowns around the world, the present international web-based survey study (15 April-15 May 2020) gauged participants' (n = 3707) level of nutrition-health misinformation discernment by presenting them with 25 statements (including unfounded or unproven claims circulated at the time), alongside the influence of information sources of varying quality on the frequency of changes in their eating behavior and the extent of misinformation held, depending on the source used for such changes. Results revealed widespread misinformation about food, eating, and health practices related to COVID-19, with the 25 statements put to participants receiving up to 43% misinformed answers (e.g., 'It is safe to eat fruits and vegetables that have been washed with soap or diluted bleach'). Whereas higher quality information sources (nutrition scientists, nutrition professionals) had the biggest influence on eating behavior change, we found greater misinformation susceptibility when relying on poor quality sources for changing diet. Appropriate discernment of misinformation was weakest amongst participants who more frequently changed their eating behavior because of information from poor quality sources, suggesting disparities in the health risks/safety of the changes performed.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Comportamento Alimentar , Frutas , Comunicação , Internet
12.
Monash Bioeth Rev ; 41(2): 87-102, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36306074

RESUMO

We examine the bioethical issues that arise from long-duration space missions, asking what there is that is distinctive about such issues. We pay particular attention to the possibility that such space missions, certainly if they lead to self-sustaining space settlements, may require human enhancement, and examine the significance of reproduction in space for bioethics. We conclude that while space bioethics raises important issues to do with human survival and reproduction in very hazardous environments, it raises no issues that are distinct from those in terrestrial bioethics. Rather, space bioethics raises extreme versions of bioethical issues that are already found in the military, when working in extreme environments (such as Antarctica), or when living in circumstances (such as in prison) where one's autonomy is severely curtailed.


Assuntos
Bioética , Humanos , Temas Bioéticos , Reprodução , Regiões Antárticas
13.
Front Physiol ; 13: 939350, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483297

RESUMO

Background: Termination of atrial fibrillation (AF), the most common arrhythmia in the United States, during catheter ablation is an attractive procedural endpoint, which has been associated with improved long-term outcome in some studies. It is not clear, however, whether it is possible to predict termination using clinical data. We developed and applied three quantitative indices in global multielectrode recordings of AF prior to ablation: average dominant frequency (ADF), spectral power index (SPI), and electrogram quality index (EQI). Methods: In N = 42 persistent AF patients (65 ± 9 years, 14% female) we collected unipolar electrograms from 64-pole baskets (Abbott, CA). We studied N = 17 patients in whom AF terminated during ablation ("Term") and N = 25 in whom it did not ("Non-term"). For each index, we determined its ability to predict ablation by computing receiver operating characteristic (ROC) and calculated the area under the curve (AUC). Results: The ADF did not differ for Term and Non-term patients at 5.28 ± 0.82 Hz and 5.51 ± 0.81 Hz, respectively (p = 0.34). Conversely, the SPI for these two groups was. 0.85 (0.80-0.92) and 0.97 (0.93-0.98) and the EQI was 0.61 (0.58-0.64) and 0.56 (0.55-0.59) (p < 0.0001). The AUC for predicting AF termination for the SPI was 0.85 ([0.68, 0.95] 95% CI), and for the EQI, 0.86 ([0.72, 0.95] 95% CI). Conclusion: Both the EQI and the SPI may provide a useful clinical tool to predict procedural ablation outcome in persistent AF patients. Future studies are required to identify which physiological features of AF are revealed by these indices and hence linked to AF termination or non-termination.

14.
Nat Commun ; 13(1): 7969, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36577750

RESUMO

Wide-field fluorescence imaging is an indispensable tool for studying large-scale biodynamics. Limited space-bandwidth product and strong light diffusion make conventional implementations incapable of high-resolution mapping of fluorescence biodistribution in three dimensions. We introduce a volumetric wide-field fluorescence microscopy based on optical astigmatism combined with fluorescence source localization, covering 5.6×5.6×0.6 mm3 imaging volume. Two alternative configurations are proposed exploiting multifocal illumination or sparse localization of point emitters, which are herein seamlessly integrated in one system. We demonstrate real-time volumetric mapping of the murine cortical microcirculation at capillary resolution without employing cranial windows, thus simultaneously delivering quantitative perfusion information across both brain hemispheres. Morphological and functional changes of cerebral vascular networks are further investigated after an acute ischemic stroke, enabling cortex-wide observation of concurrent collateral recruitment events occurring on a sub-second scale. The reported technique thus offers a wealth of unmatched possibilities for non- or minimally invasive imaging of biodynamics across scales.


Assuntos
AVC Isquêmico , Camundongos , Animais , Microcirculação , Distribuição Tecidual , Crânio , Microscopia de Fluorescência
15.
Adv Sci (Weinh) ; : e2204782, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36403231

RESUMO

Detailed characterization of microvascular alterations requires high-resolution 3D imaging methods capable of providing both morphological and functional information. Existing optical microscopy tools are routinely used for microangiography, yet offer suboptimal trade-offs between the achievable field of view and spatial resolution with the intense light scattering in biological tissues further limiting the achievable penetration depth. Herein, a new approach for volumetric deep-tissue microangiography based on stereovision combined with super-resolution localization imaging is introduced that overcomes the spatial resolution limits imposed by light diffusion and optical diffraction in wide-field imaging configurations. The method capitalizes on localization and tracking of flowing fluorescent particles in the second near-infrared window (NIR-II, ≈1000-1700 nm), with the third (depth) dimension added by triangulation and stereo-matching of images acquired with two short-wave infrared cameras operating in a dual-view mode. The 3D imaging capability enabled with the proposed method facilitates a detailed visualization of microvascular networks and an accurate blood flow quantification. Experiments performed in tissue-mimicking phantoms demonstrate that high resolution is preserved up to a depth of 4 mm in a turbid medium. Transcranial microangiography of the entire murine cortex and penetrating vessels is further demonstrated at capillary level resolution.

16.
Adv Sci (Weinh) ; 9(24): e2105588, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35798308

RESUMO

Modern optical neuroimaging approaches are expanding the ability to elucidate complex brain function. Diverse imaging contrasts enable direct observation of neural activity with functional sensors along with the induced hemodynamic responses. To date, decoupling the complex interplay of neurovascular coupling and dynamical physiological states has remained challenging when employing single-modality functional neuroimaging readings. A hybrid fluorescence optoacoustic tomography platform combined with a custom data processing pipeline based on statistical parametric mapping is devised, attaining the first noninvasive observation of simultaneous calcium and hemodynamic activation patterns using optical contrasts. Correlated changes in the oxy- and deoxygenated hemoglobin, total hemoglobin, oxygen saturation, and rapid GCaMP6f fluorescence signals are observed in response to peripheral sensory stimulation. While the concurrent epifluorescence serves to corroborate and complement the functional optoacoustic observations, the latter further aids in decoupling the rapid calcium responses from the slowly varying background in the fluorescence recordings mediated by hemodynamic changes. The hybrid imaging platform expands the capabilities of conventional neuroimaging methods to provide more comprehensive functional readings for studying neurovascular and neurometabolic coupling mechanisms and related diseases.


Assuntos
Acoplamento Neurovascular , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Neuroimagem Funcional , Hemoglobinas/metabolismo , Camundongos , Neuroimagem/métodos , Acoplamento Neurovascular/fisiologia
17.
Sci Educ (Dordr) ; 31(5): 1263-1280, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35497258

RESUMO

The issue of trust in science has come to the fore in recent years. I focus on vaccines, first looking at what is known about trust in vaccines and then concentrating on whether what science education teaches about vaccines can be trusted. I present an argument to connect the phenomenon of vaccine hesitancy to the issue of trust and then argue for what an education about vaccines in school science might look like that takes seriously the notion of respect for students, including students who hold views about vaccination with which science teachers might disagree. Trust in others (people and institutions) varies greatly, both between countries and within countries, and depends on the characteristics of both trustor and trustee, and there are great differences in the extent to which people trust vaccines. However, it is a mistake to think that people who do not trust vaccines are simply ill-informed. There are a range of reasons for rejecting what is often an unexamined narrative about vaccines, namely that vaccines are always desirable. Many people come from communities that have sound reasons for being suspicious of what they are told by governments, business and the medical establishment. COVID-19 and earlier reactions to vaccination health scares show how important high-quality education about vaccines is. Much of that education can take place out of school, but the foundations are laid in school. Vaccine rejection and hesitancy have major global public health implications. Good quality vaccine education should help students understand about relevant biology and the nature of science; it should also be respectful of all students, including those who come from families that reject vaccines or are hesitant about them.

18.
J Bone Miner Res ; 37(5): 1032-1043, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35220594

RESUMO

Skull bone development is a dynamic and well-coordinated process playing a key role in maturation and maintenance of the bone marrow (BM), fracture healing, and progression of diseases such as osteoarthritis or osteoporosis. At present, dynamic transformation of the growing bone (osteogenesis) as well as its vascularization (angiogenesis) remain largely unexplored due to the lack of suitable in vivo imaging techniques capable of noninvasive visualization of the whole developing calvaria at capillary-level resolution. We present a longitudinal study on skull bone development using ultrasound-aided large-scale optoacoustic microscopy (U-LSOM). Skull bone morphogenesis and microvascular growth patterns were monitored in three common mouse strains (C57BL/6J, CD-1, and Athymic Nude-Foxn1nu) at the whole-calvaria scale over a 3-month period. Strain-specific differences in skull development were revealed by quantitative analysis of bone and vessel parameters, indicating the coupling between angiogenesis and osteogenesis during skull bone growth in a minimally invasive and label-free manner. The method further enabled identifying BM-specific sinusoidal vessels, and superficial skull vessels penetrating into BM compartments. Our approach furnishes a new high-throughput longitudinal in vivo imaging platform to study morphological and vascular skull alterations in health and disease, shedding light on the critical links between blood vessel formation, skull growth, and regeneration. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).


Assuntos
Microscopia , Crânio , Animais , Estudos Longitudinais , Camundongos , Camundongos Endogâmicos C57BL , Microscopia/métodos , Neovascularização Patológica , Osteogênese , Crânio/diagnóstico por imagem
19.
IEEE Trans Med Imaging ; 41(4): 846-856, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34735340

RESUMO

Spherical matrix arrays represent an advantageous tomographic detection geometry for non-invasive deep tissue mapping of vascular networks and oxygenation with volumetric optoacoustic tomography (VOT). Hybridization of VOT with ultrasound (US) imaging remains difficult with this configuration due to the relatively large inter-element pitch of spherical arrays. We suggest a new approach for combining VOT and US contrast-enhanced 3D imaging employing injection of clinically-approved microbubbles. Power Doppler (PD) and US localization imaging were enabled with a sparse US acquisition sequence and model-based inversion based on infimal convolution of total variation (ICTV) regularization. In vitro experiments in tissue-mimicking phantoms and in living mouse brain demonstrate the powerful capabilities of the new dual-mode imaging approach attaining 80 µm spatial resolution and a more than 10 dB signal to noise improvement with respect to a classical delay and sum beamformer. Microbubble localization and tracking allowed for flow velocity mapping up to 40 mm/s.


Assuntos
Microbolhas , Tomografia , Animais , Meios de Contraste , Imageamento Tridimensional , Camundongos , Imagens de Fantasmas , Ultrassonografia/métodos
20.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34732573

RESUMO

Propagation of electromechanical waves in excitable heart muscles follows complex spatiotemporal patterns holding the key to understanding life-threatening arrhythmias and other cardiac conditions. Accurate volumetric mapping of cardiac wave propagation is currently hampered by fast heart motion, particularly in small model organisms. Here we demonstrate that ultrafast four-dimensional imaging of cardiac mechanical wave propagation in entire beating murine heart can be accomplished by sparse optoacoustic sensing with high contrast, ∼115-µm spatial and submillisecond temporal resolution. We extract accurate dispersion and phase velocity maps of the cardiac waves and reveal vortex-like patterns associated with mechanical phase singularities that occur during arrhythmic events induced via burst ventricular electric stimulation. The newly introduced cardiac mapping approach is a bold step toward deciphering the complex mechanisms underlying cardiac arrhythmias and enabling precise therapeutic interventions.


Assuntos
Arritmias Cardíacas/diagnóstico por imagem , Técnicas de Imagem Cardíaca , Tomografia Computadorizada Quadridimensional , Coração/diagnóstico por imagem , Técnicas Fotoacústicas , Animais , Arritmias Cardíacas/fisiopatologia , Feminino , Coração/fisiopatologia , Preparação de Coração Isolado , Camundongos
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