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Calcium imaging using two-photon scanning microscopy has become an essential tool in neuroscience. However, in its typical implementation, the tradeoffs between fields of view, acquisition speeds, and depth restrictions in scattering brain tissue pose severe limitations. Here, using an integrated systems-wide optimization approach combined with multiple technical innovations, we introduce a new design paradigm for optical microscopy based on maximizing biological information while maintaining the fidelity of obtained neuron signals. Our modular design utilizes hybrid multi-photon acquisition and allows volumetric recording of neuroactivity at single-cell resolution within up to 1 × 1 × 1.22 mm volumes at up to 17 Hz in awake behaving mice. We establish the capabilities and potential of the different configurations of our imaging system at depth and across brain regions by applying it to in vivo recording of up to 12,000 neurons in mouse auditory cortex, posterior parietal cortex, and hippocampus.
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Microscopia/métodos , Imagem Molecular/métodos , Neuroimagem/métodos , Animais , Encéfalo/fisiologia , Cálcio/metabolismo , Feminino , Hipocampo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Análise de Célula Única/métodosRESUMO
High-throughput volumetric fluorescent microscopy pipelines can spatially integrate whole-brain structure and function at the foundational level of single cells. However, conventional fluorescent protein (FP) modifications used to discriminate single cells possess limited efficacy or are detrimental to cellular health. Here, we introduce a synthetic and nondeleterious nuclear localization signal (NLS) tag strategy, called "Arginine-rich NLS" (ArgiNLS), that optimizes genetic labeling and downstream image segmentation of single cells by restricting FP localization near-exclusively in the nucleus through a poly-arginine mechanism. A single N-terminal ArgiNLS tag provides modular nuclear restriction consistently across spectrally separate FP variants. ArgiNLS performance in vivo displays functional conservation across major cortical cell classes and in response to both local and systemic brain-wide AAV administration. Crucially, the high signal-to-noise ratio afforded by ArgiNLS enhances machine learning-automated segmentation of single cells due to rapid classifier training and enrichment of labeled cell detection within 2D brain sections or 3D volumetric whole-brain image datasets, derived from both staining-amplified and native signal. This genetic strategy provides a simple and flexible basis for precise image segmentation of genetically labeled single cells at scale and paired with behavioral procedures.
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Arginina , Sinais de Localização Nuclear , Análise de Célula Única , Animais , Sinais de Localização Nuclear/metabolismo , Arginina/metabolismo , Análise de Célula Única/métodos , Camundongos , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Núcleo Celular/metabolismo , Microscopia de Fluorescência/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Razão Sinal-RuídoRESUMO
The mammalian brain is a densely interconnected network that consists of millions to billions of neurons. Decoding how information is represented and processed by this neural circuitry requires the ability to capture and manipulate the dynamics of large populations at high speed and high resolution over a large area of the brain. Although the use of optical approaches by the neuroscience community has rapidly increased over the past two decades, most microscopy approaches are unable to record the activity of all neurons comprising a functional network across the mammalian brain at relevant temporal and spatial resolutions. In this review, we survey the recent development in optical technologies for Ca2+ imaging in this regard and provide an overview of the strengths and limitations of each modality and its potential for scalability. We provide guidance from the perspective of a biological user driven by the typical biological applications and sample conditions. We also discuss the potential for future advances and synergies that could be obtained through hybrid approaches or other modalities.
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Encéfalo , Vias Neurais/fisiologia , Neurônios/fisiologia , Imagem Óptica/métodos , Imagem Óptica/normas , Animais , Encéfalo/citologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Humanos , Vias Neurais/diagnóstico por imagemRESUMO
Three-dimensional single-pixel imaging (3D SPI) has become an attractive imaging modality for both biomedical research and optical sensing. 3D-SPI techniques generally depend on time-of-flight or stereovision principle to extract depth information from backscattered light. However, existing implementations for these two optical schemes are limited to surface mapping of 3D objects at depth resolutions, at best, at the millimeter level. Here, we report 3D light-field illumination single-pixel microscopy (3D-LFI-SPM) that enables volumetric imaging of microscopic objects with a near-diffraction-limit 3D optical resolution. Aimed at 3D space reconstruction, 3D-LFI-SPM optically samples the 3D Fourier spectrum by combining 3D structured light-field illumination with single-element intensity detection. We build a 3D-LFI-SPM prototype that provides an imaging volume of â¼390 × 390 × 3,800 µm3 and achieves 2.7-µm lateral resolution and better than 37-µm axial resolution. Its capability of 3D visualization of label-free optical absorption contrast is demonstrated by imaging single algal cells in vivo. Our approach opens broad perspectives for 3D SPI with potential applications in various fields, such as biomedical functional imaging.
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Severe muscle injury causes distress and difficulty in humans. Studying the high regenerative ability of the axolotls may provide hints for the development of an effective treatment for severe injuries to muscle tissue. Here, we examined the regenerative process in response to a muscle injury in axolotls. We found that axolotls are capable of complete regeneration in response to a partial muscle resection called volumetric muscle loss (VML), which mammals cannot perfectly regenerate. We investigated the mechanisms underlying this high regenerative capacity in response to VML, focusing on the migration of muscle satellite cells and the extracellular matrix (ECM) formed during VML injury. Axolotls form tenascin-C (TN-C)-enriched ECM after VML injury. This TN-C-enriched ECM promotes the satellite cell migration. We confirmed the importance of TN-C in successful axolotl muscle regeneration by creating TN-C mutant animals. Our results suggest that the maintenance of a TN-C-enriched ECM environment after muscle injury promotes the release of muscle satellite cells and supports eventually high muscle regenerative capacity. In the future, better muscle regeneration may be achieved in mammals through the maintenance of TN-C expression.
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Ambystoma mexicanum , Tenascina , Animais , Humanos , Tenascina/genética , Tenascina/metabolismo , Ambystoma mexicanum/metabolismo , Matriz Extracelular/metabolismo , Músculos/metabolismo , Mamíferos/metabolismo , Músculo Esquelético/metabolismoRESUMO
BACKGROUND: Three-dimensional (3D) T1-weighted MRI sequences such as the magnetization prepared rapid gradient echo (MPRAGE) sequence are important for assessing regional cortical atrophy in the clinical evaluation of dementia but have long acquisition times and are prone to motion artifact. The recently developed Scout Accelerated Motion Estimation and Reduction (SAMER) retrospective motion correction method addresses motion artifact within clinically-acceptable computation times and has been validated through qualitative evaluation in inpatient and emergency settings. METHODS: We evaluated the quantitative accuracy of morphometric analysis of SAMER motion-corrected compared to non-motion-corrected MPRAGE images by estimating cortical volume and thickness across neuroanatomical regions in two subject groups: (1) healthy volunteers and (2) patients undergoing evaluation for dementia. In part (1), we used a set of 108 MPRAGE reconstructed images derived from 12 healthy volunteers to systematically assess the effectiveness of SAMER in correcting varying degrees of motion corruption, ranging from mild to severe. In part (2), 29 patients who were scheduled for brain MRI with memory loss protocol and had motion corruption on their clinical MPRAGE scans were prospectively enrolled. RESULTS: In part (1), SAMER resulted in effective correction of motion-induced cortical volume and thickness reductions. We observed systematic increases in the estimated cortical volume and thickness across all neuroanatomical regions and a relative reduction in percent error values compared to reference standard scans of up to 66 % for the cerebral white matter volume. In part (2), SAMER resulted in statistically significant volume increases across anatomical regions, with the most pronounced increases seen in the parietal and temporal lobes, and general reductions in percent error relative to reference standard clinical scans. CONCLUSION: SAMER improves the accuracy of morphometry through systematic increases and recovery of the estimated cortical volume and cortical thickness following motion correction, which may affect the evaluation of regional cortical atrophy in patients undergoing evaluation for dementia.
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Artefatos , Encéfalo , Imageamento por Ressonância Magnética , Humanos , Feminino , Masculino , Imageamento por Ressonância Magnética/métodos , Idoso , Pessoa de Meia-Idade , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Transtornos da Memória/diagnóstico por imagem , Transtornos da Memória/fisiopatologia , Transtornos da Memória/patologia , Idoso de 80 Anos ou mais , Movimento (Física) , Processamento de Imagem Assistida por Computador/métodos , Demência/diagnóstico por imagem , Demência/fisiopatologia , Demência/patologiaRESUMO
HoloTile is a patented computer generated holography approach with the aim of reducing the speckle noise caused by the overlap of the non-trivial physical extent of the point spread function in Fourier holographic systems from adjacent frequency components. By combining tiling of phase-only of rapidly generated sub-holograms with a PSF-shaping phase profile, each frequency component-or output 'pixel'- in the Fourier domain is shaped to a desired non-overlapping profile. In this paper, we show the high-resolution, speckle-reduced reconstructions that can be achieved with HoloTile, as well as present new HoloTile modalities, including an expanded list of PSF options with new key properties. In addition, we discuss numerous applications for which HoloTile, its rapid hologram generation, and the new PSF options may be an ideal fit, including optical trapping and manipulation of particles, volumetric additive printing, information transfer and quantum communication.
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Despite increasing interest in the dynamics of functional brain networks, most studies focus on the changing relationships over time between spatially static networks or regions. Here we propose an approach to study dynamic spatial brain networks in human resting state functional magnetic resonance imaging (rsfMRI) data and evaluate the temporal changes in the volumes of these 4D networks. Our results show significant volumetric coupling (i.e., synchronized shrinkage and growth) between networks during the scan, that we refer to as dynamic spatial network connectivity (dSNC). We find that several features of such dynamic spatial brain networks are associated with cognition, with higher dynamic variability in these networks and higher volumetric coupling between network pairs positively associated with cognitive performance. We show that these networks are modulated differently in individuals with schizophrenia versus typical controls, resulting in network growth or shrinkage, as well as altered focus of activity within a network. Schizophrenia also shows lower spatial dynamical variability in several networks, and lower volumetric coupling between pairs of networks, thus upholding the role of dynamic spatial brain networks in cognitive impairment seen in schizophrenia. Our data show evidence for the importance of studying the typically overlooked voxel-wise changes within and between brain networks.
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Conectoma , Imageamento por Ressonância Magnética , Rede Nervosa , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/fisiopatologia , Adulto , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Masculino , Feminino , Adulto Jovem , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/etiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologiaRESUMO
Volumetric loss is one of the challenging issues in muscle tissue structure that causes functio laesa. Tissue engineering of muscle tissue using suitable hydrogels is an alternative to restoring the physiological properties of the injured area. Here, myogenic properties of type I collagen (0.5%) and keratin (0.5%) were investigated in a mouse model of biceps femoris injury. Using FTIR, gelation time, and rheological analysis, the physicochemical properties of the collagen (Col)/Keratin scaffold were analyzed. Mouse C2C12 myoblast-laden Col/Keratin hydrogels were injected into the injury site and histological examination plus western blotting were performed to measure myogenic potential after 15 days. FTIR indicated an appropriate interaction between keratin and collagen. The blend of Col/Keratin delayed gelation time when compared to the collagen alone group. Rheological analysis revealed decreased stiffening in blended Col/Keratin hydrogel which is favorable for the extrudability of the hydrogel. Transplantation of C2C12 myoblast-laden Col/Keratin hydrogel to injured muscle tissues led to the formation of newly generated myofibers compared to cell-free hydrogel and collagen groups (p < 0.05). In the C2C12 myoblast-laden Col/Keratin group, a low number of CD31+ cells with minimum inflammatory cells was evident. Western blotting indicated the promotion of MyoD in mice that received cell-laden Col/Keratin hydrogel compared to the other groups (p < 0.05). Despite the increase of the myosin cell-laden Col/Keratin hydrogel group, no significant differences were obtained related to other groups (p > 0.05). The blend of Col/Keratin loaded with myoblasts provides a suitable myogenic platform for the alleviation of injured muscle tissue.
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Queratinas , Desenvolvimento Muscular , Músculo Esquelético , Animais , Camundongos , Músculo Esquelético/lesões , Músculo Esquelético/metabolismo , Queratinas/metabolismo , Linhagem Celular , Hidrogéis/química , Neovascularização Fisiológica/efeitos dos fármacos , Engenharia Tecidual/métodos , Modelos Animais de Doenças , Colágeno/metabolismo , Mioblastos/metabolismo , Mioblastos/citologia , Masculino , Alicerces Teciduais/química , AngiogêneseRESUMO
Additive manufacturing (AM) of ceramics has significantly contributed to advancements in ceramic fabrication, solving some of the difficulties of conventional ceramic processing and providing additional possibilities for the structure and function of components. However, defects induced by the layer-by-layer approach on which traditional AM techniques are based still constitute a challenge to address. This study presents the volumetric AM of a SiOC ceramic from a preceramic polymer using xolography, a linear volumetric AM process that allows to avoid the staircase effect typical of other vat photopolymerization techniques. Besides optimizing the trade-off between preceramic polymer content and transmittance, a pore generator is introduced to create transient channels for gas release before decomposition of the organic constituents and moieties, resulting in crack-free solid ceramic structures even at low ceramic yield. Formulation optimization alleviated sinking of printed parts during printing and prevented shape distortion. Complex solid and porous ceramic structures with a smooth surface and sharp features are fabricated under the optimized parameters. This work provides a new method for the AM of ceramics at µm/mm scale with high surface quality and large geometry variety in an efficient way, opening the possibility for applications in fields such as micromechanical systems and microelectronic components.
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Concomitant achievement of all three performance pillars of a supercapacitor device, namely gravimetric, areal, and volumetric capacitance is a grand challenge. Nevertheless, its fulfilment is indispensable for commercial usage. Although, high compactness is the fundamental requirement to achieve high volumetric performance, it severely affects ion transportation in thick electrodes. Such trade-off makes it extremely challenging to realize very high areal and volumetric performance simultaneously. Here, a collapsed hydrogel strategy is introduced to develop MXene/cellulose nanofiber (CNF) based densified electrodes that offer excellent ion transportation despite a massive increase in areal mass loading (>70 mg cm-2). Quasi-oriented MXene/CNF (MXCF) hydrogels are produced through an electric field-guided co-assembly technique. Ambient dehydration of these hydrogels incorporates numerous pores in the resultant compact electrodes due to crumpling of the MXene sheets, while CNF ensures connectivity among the locally blocked pores in different length scales. The resultant collapsed MXCF densified electrode shows a remarkably high areal capacitance of 16 F cm-2 while simultaneously displaying a high volumetric capacitance of 849.8 F cm-3 at an ultrahigh mass loading of up to 73.4 mg cm-2. The universality of strategy, including the co-assembly of hydrogel and its collapse, is further demonstrated to develop high-performance asymmetric and wearable devices.
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Few studies have proved that bioprinting itself helps recapitulate native tissue functions mainly because the bioprinted macro shape can rarely, if ever, influence cell function. This can be more problematic in bioprinting cartilage, generally considered more challenging to engineer. Here a new method is shown to micro-pattern chondrocytes within bioprinted sub-millimeter micro tissues, denoted as patterned micro-articular-cartilages tissues (PA-MCTs). Under the sole influence of bioprinted cellular patterns. A pattern scoring system is developed after over 600 bioprinted cellular patterns are analyzed. The top-scored pattern mimics that of the isogenous group in native articular cartilage. Under the sole influence of this pattern during PA-MCTs bio-assembling into macro-cartilage and repairing cartilage defects, chondrogenic cell phenotype is preserved, and cartilagenesis is initiated and maintained. Neocartilage tissues from individual and assembled PA-MCTs are comparable to native articular cartilage and superior to cartilage bioprinted with homogeneously distributed cells in morphology, biochemical components, cartilage-specific protein and gene expression, mechanical properties, integration with host tissues, zonation forming and stem cell chondrogenesis. PA-MCTs can also be used as osteoarthritic and healthy cartilage models for therapeutic drug screening and cartilage development studies. This cellular patterning technique can pave a new way for bioprinting to recapitulate native tissue functions via tissue genesis.
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Bioimpressão , Cartilagem Articular , Bioimpressão/métodos , Cartilagem Articular/citologia , Animais , Engenharia Tecidual/métodos , Condrogênese , Regeneração , Condrócitos/citologia , Condrócitos/metabolismo , Humanos , Alicerces Teciduais/químicaRESUMO
Brain imaging work aimed at increased classification of dyslexia has underscored an important relationship between anterior (i.e., the inferior frontal gyrus; IFG) and posterior (i.e., superior temporal gyrus and supramarginal gyrus) brain regions. The extent to which the three components of the inferior frontal gyrus, namely the pars orbitalis, triangularis, and opercularis, are differentially related to the posterior regions, namely the superior temporal gyrus and supramarginal gyrus, needs further elucidation. Information about the nature of the anterior-posterior connections would facilitate our understanding of the neural underpinnings associated with dyslexia. Adult participants (N = 38; 16 with dyslexia) took part in an MRI study, whereby high-resolution structural scans were obtained. Volumetric asymmetry of the three regions of the IFG, the superior temporal gyrus, and the supramarginal gyrus was extracted. Significant differences were found for each of the three IFG regions, such that skilled readers had a greater leftward asymmetry of the orbitalis and triangularis, and greater rightward asymmetry of the opercularis, when compared to individuals with dyslexia. Furthermore, the pars triangularis was significantly associated with leftward asymmetry of the superior temporal gyrus for skilled but not dyslexic participants. For individuals with dyslexia, the cortical asymmetry of the IFG, and the corresponding connections with other reading-related brain regions, is inherently different from skilled readers. We discuss our findings in the context of the print-to-speech framework to further our understanding of the neural underpinnings associated with dyslexia.
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Dislexia , Substância Cinzenta , Adulto , Humanos , Substância Cinzenta/diagnóstico por imagem , Dislexia/diagnóstico por imagem , Encéfalo , Leitura , Córtex Pré-Frontal , Mapeamento Encefálico , Imageamento por Ressonância Magnética/métodosRESUMO
Volumetric data provide unprecedented structural insight to the reproductive tract and add vital anatomical context to the relationships between organs. The morphology of the female reproductive tract in non-avian reptiles varies between species, corresponding to a broad range of reproductive modes and providing valuable insight to comparative investigations of reproductive anatomy. However, reproductive studies in reptilian models, such as the brown anole studied here, have historically relied on histological methods to understand the anatomy. While these methods are highly effective for characterizing the cell types present in each organ, histological methods lose the 3D relationships between images and leave the architecture of the organ system poorly understood. We present the first comprehensive volumetric analyses of the female brown anole reproductive tract using two non-invasive, non-destructive imaging modalities: micro-computed tomography (microCT) and optical coherence tomography (OCT). Both are specialized imaging technologies that facilitate high-throughput imaging and preserve three-dimensional information. This study represents the first time that microCT has been used to study all reproductive organs in this species and the very first time that OCT has been applied to this species. We show how the non-destructive volumetric imaging provided by each modality reveals anatomical context including orientation and relationships between reproductive organs of the anole lizard. In addition to broad patterns of morphology, both imaging modalities provide the high resolution necessary to capture details and key anatomical features of each organ. We demonstrate that classic histological features can be appreciated within whole-organ architecture in volumetric imaging using microCT and OCT, providing the complementary information necessary to understand the relationships between tissues and organs in the reproductive system. This side-by-side imaging analysis using microCT and OCT allows us to evaluate the specific advantages and limitations of these two methods for the female reptile reproductive system.
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Genitália Feminina , Lagartos , Tomografia de Coerência Óptica , Microtomografia por Raio-X , Animais , Feminino , Microtomografia por Raio-X/métodos , Microtomografia por Raio-X/veterinária , Tomografia de Coerência Óptica/métodos , Tomografia de Coerência Óptica/veterinária , Lagartos/anatomia & histologia , Genitália Feminina/diagnóstico por imagem , Genitália Feminina/anatomia & histologia , Imageamento Tridimensional/métodos , Imageamento Tridimensional/veterináriaRESUMO
OBJECTIVE: The aim of this study was to investigate the mid-term results of stented-assisted balloon-induced intimal disruption and relamination (STABILISE) in patients with aortic dissection with the implementation of volumetric analysis. METHODS: This was a single-center retrospective analysis of prospectively collected data. From May 2017 to September 2022, 42 patients underwent STABILISE for acute complicated or subacute high-risk aortic dissection. STABILISE was completed with distal extended endovascular aortic repair in 24 patients. A computed tomography scan was performed at baseline, before hospital discharge, and at 1, 3, and 5 years. Perfused total aortic, true lumen, and false lumen volumes were assessed for thoracic, visceral, and aorto-iliac segment. The ratio between false lumen and total volume was named perfusion dissection index (PDI). Complete remodeling was defined as PDI = 0, and positive remodeling as PDI ≤0.1. RESULTS: Technical success was 97.6%. No 30-day deaths, spinal cord injuries, or retrograde dissections were observed. Mean follow-up was 44 ± 19.4 months. Thoracic diameter was lower at last available computed tomography scan (36.7 vs 33.0 mm; P = .01). Aortic growth >5 mm was observed in 9.5% of the patients. Thoracic and visceral aortic complete remodeling were 92.8% and 83.3%, respectively, with no difference between acute and subacute group. Distal extended endovascular aortic repair significantly increased complete remodeling in the aorto-iliac segment, compared with STABILISE alone (69.6% vs 21.4%; P < .001). Freedom from vascular reinterventions at 3 years was 83.1% (95% confidence interval, 71.5%-96.6%). Total PDI ≤0.1 at first postoperative control was a predictor of vascular reinterventions (P < .0001). CONCLUSIONS: STABILISE is a safe and feasible technique associated with high mid-term rates of complete remodeling in the thoracic and visceral aorta. Volumetric analysis allows the quantification of aortic remodeling and represents a predictor of aortic reinterventions.
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Dissecção Aórtica , Stents , Humanos , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Masculino , Feminino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Fatores de Tempo , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/efeitos adversos , Remodelação Vascular , Angiografia por Tomografia Computadorizada , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/cirurgia , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/efeitos adversos , Angioplastia com Balão/instrumentação , Angioplastia com Balão/efeitos adversos , Aneurisma da Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Valor Preditivo dos Testes , Reoperação , Aortografia , Fatores de RiscoRESUMO
BACKGROUND: The effective dose to circulating immune cells (EDIC) is associated with survival in lung and esophageal cancer patients. This study aimed to evaluate the benefit of intensity-modulated proton therapy (IMPT) for EDIC reduction as compared to volumetric modulated arc therapy (VMAT) in patients with locally advanced breast cancer (BC). MATERIALS AND METHODS: Ten BC patients treated with locoregional VMAT after breast-conserving surgery were included. Mean dose to the heart (MHD), lungs (MLD), and liver (MlD), as well as the integral dose to the body (ITD), were retrieved, and we calculated EDIC as 0.12â¯× MLDâ¯+ 0.08â¯× MHDâ¯+ 0.15â¯× 0.85â¯× â(n/45)â¯× MlDâ¯+ (0.45â¯+ 0.35â¯× 0.85â¯× â(n/45))â¯× ITD/(62â¯× 103), where n is the number of fractions. EDIC was compared between VMAT and IMPT plans. RESULTS: Median EDIC was reduced from 3.37â¯Gy (range: 2.53-5.99) with VMAT to 2.13â¯Gy (1.31-3.77) with IMPT (pâ¯< 0.01). For left-sided BC patients, EDIC was reduced from 3.15â¯Gy (2.53-3.78) with VMAT to 1.65â¯Gy (1.31-3.77) with IMPT (pâ¯< 0.01). For right-sided BC patients, EDIC was reduced from 5.60â¯Gy (5.06-5.99) with VMAT to 3.38â¯Gy (3.10-3.77) with IMPT (pâ¯< 0.01). Right-sided BC patients had a higher EDIC irrespective of the technique. Integral dose reduction was the main driver of EDIC reduction with IMPT and was associated with lung sparing for left-sided BC patients or liver sparing for right-sided BC patients. CONCLUSION: IMPT significantly reduced EDIC in BC patients undergoing locoregional adjuvant radiotherapy. Integral total dose reduction, associated with improved lung sparing in left-sided BC patients or liver sparing in right-sided BC patients, mainly drove EDIC reduction with IMPT. The emergence of dynamic models taking into account the circulatory kinetics of immune cells may improve the accuracy of the estimate of the dose received by the immune system compared to calculation of the EDIC, which is based solely on static dosimetric data.
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BACKGROUND: A simultaneous integrated boost (SIB) may result in increased out-of-field (DOOF) and photoneutron (HPN) doses in volumetric modulated arc therapy (VMAT) for prostate cancer (PCA). This work therefore aimed to compare DOOF and HPN in flattened (FLAT) and flattening filter-free (FFF) 6MV and 10-MV VMAT treatment plans with and without SIB. METHODS: Eight groups of 30 VMAT plans for PCA with 6 MV or 10 MV, with or without FF and with uniform (2â¯Gy) or SIB target dose (2.5/3.0â¯Gy) prescriptions (CONV, SIB), were generated. All 240 plans were delivered on a slab-phantom and compared with respect to measured DOOF and HPN in 61.8â¯cm distance from the isocenter. The 6 and 10-MV flattened VMAT plans with conventional fractionation (6- and 10-MV FLAT CONV) served as standard reference groups. Doses were analyzed as a function of delivered monitor units (MU) and weighted equivalent square field size Aeq. Pearson's correlation coefficients between the presented quantities were determined. RESULTS: The SIB plans resulted in decreased HPN over an entire prostate RT treatment course (10-MV SIB vs. CONV -38.2%). Omission of the flattening filter yielded less HPN (10-MV CONV -17.2%; 10-MV SIB -22.5%). The SIB decreased DOOF likewise by 39% for all given scenarios, while the FFF mode reduced DOOF on average by 60%. A strong Pearson correlation was found between MU and HPN (râ¯> 0.9) as well as DOOF (0.7â¯< râ¯< 0.9). CONCLUSION: For a complete treatment, SIB reduces both photoneutron and OOF doses to almost the same extent as FFF deliveries. It is recommended to apply moderately hypofractionated 6MV SIB FFF-VMAT when considering photoneutron or OOF doses.
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Neoplasias da Próstata , Radioterapia de Intensidade Modulada , Masculino , Humanos , Radioterapia de Intensidade Modulada/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias da Próstata/radioterapia , Fracionamento da Dose de Radiação , Próstata , Dosagem RadioterapêuticaRESUMO
BACKGROUND: Although robot-assisted radical prostatectomy (RARP) and intensity-modulated radiotherapy are the leading respective techniques of prostatectomy and radiotherapy for localized prostate cancer, almost no study has directly compared their outcomes; none have compared mortality outcomes. METHODS: We compared 6year outcomes of RARP (nâ¯= 500) and volumetric modulated arc therapy (VMAT, a rotational intensity-modulated radiotherapy, nâ¯= 360) in patients with cT1-4N0M0 prostate cancer. We assessed oncological outcomes, namely overall survival (OS), cancer-specific survival (CSS), radiological recurrence-free survival (rRFS), and biochemical recurrence-free survival (bRFS), using propensity score matching (PSM). We also assessed treatment-related complication outcomes of prostatectomy and radiotherapy. RESULTS: The median follow-up duration was 79 months (>â¯6 years). PSM generated a matched cohort of 260 patients (130 per treatment group). In the matched cohort, RARP and VMAT showed equivalent results for OS, CSS, and rRFS: both achieved excellent 6year outcomes for OS (>â¯96%), CSS (>â¯98%), and rRFS (>â¯91%). VMAT had significantly longer bRFS than RARP, albeit based on different definitions of biochemical recurrence. Regarding complication outcomes, patients who underwent RARP had minimal (2.6%) severe perioperative complications and achieved excellent continence recovery (91.6 and 68.8% of the patients achieved ≤â¯1 pad/day and pad-free, respectively). Patients who underwent VMAT had an acceptable rate (20.0%) of grade ≥â¯2 genitourinary complications and a very low rate (4.4%) of grade ≥â¯2 gastrointestinal complications. CONCLUSION: On the basis of PSM after a 6-year follow-up, RARP and VMAT showed equivalent and excellent oncological outcomes, as well as acceptable complication profiles.
Assuntos
Pontuação de Propensão , Prostatectomia , Neoplasias da Próstata , Radioterapia de Intensidade Modulada , Procedimentos Cirúrgicos Robóticos , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/mortalidade , Radioterapia de Intensidade Modulada/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Pessoa de Meia-Idade , Idoso , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Estadiamento de Neoplasias , Seguimentos , Taxa de Sobrevida , Intervalo Livre de DoençaRESUMO
BACKGROUND: Identifying biological drivers of mammographic breast density (MBD), a strong risk factor for breast cancer, could provide insight into breast cancer etiology and prevention. Studies on dietary factors and MBD have yielded conflicting results. There are, however, very limited data on the associations of dietary biomarkers and MBD. OBJECTIVE: We aimed to investigate the associations of vitamins and related cofactor metabolites with MBD in premenopausal women. METHODS: We measured 37 vitamins and related cofactor metabolites in fasting plasma samples of 705 premenopausal women recruited during their annual screening mammogram at the Washington University School of Medicine, St. Louis, MO. Volpara was used to assess volumetric percent density (VPD), dense volume (DV), and nondense volume (NDV). We estimated the least square means of VPD, DV, and NDV across quartiles of each metabolite, as well as the regression coefficient of a metabolite in continuous scale from multiple covariate-adjusted linear regression. We corrected for multiple testing using the Benjamini-Hochberg procedure to control the false discover rate (FDR) at a 5% level. RESULTS: Participants' mean VPD was 10.5%. Two vitamin A metabolites (ß-cryptoxanthin and carotene diol 2) were positively associated, and one vitamin E metabolite (γ-tocopherol) was inversely associated with VPD. The mean VPD increased across quartiles of ß-cryptoxanthin (Q1 = 7.2%, Q2 = 7.7%, Q3 = 8.4%%, Q4 = 9.2%; P-trend = 1.77E-05, FDR P value = 1.18E-03). There was a decrease in the mean VPD across quartiles of γ-tocopherol (Q1 = 9.4%, Q2 = 8.1%, Q3 = 8.0%, Q4 = 7.8%; P -trend = 4.01E-03, FDR P value = 0.04). Seven metabolites were associated with NDV: 3 vitamin E (γ-CEHC glucuronide, δ-CEHC, and γ-tocopherol) and 1 vitamin C (gulonate) were positively associated, whereas 2 vitamin A (carotene diol 2 and ß-cryptoxanthin) and 1 vitamin C (threonate) were inversely associated with NDV. No metabolite was significantly associated with DV. CONCLUSION: We report novel associations of vitamins and related cofactor metabolites with MBD in premenopausal women.
Assuntos
Densidade da Mama , Neoplasias da Mama , Feminino , Humanos , Vitaminas , Vitamina A , gama-Tocoferol , beta-Criptoxantina , Neoplasias da Mama/etiologia , Fatores de Risco , Vitamina K , Ácido AscórbicoRESUMO
The aim of this study is to investigate the role of the combination of volumetric and dissemination parameters obtained from pretreatment 18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in predicting the interim response and progression status in patients with Hodgkin lymphoma (HL). Pretreatment PET/CT images of HL patients were analyzed with LIFEx software, and volumes of interest (VOIs) were drawn with a fixed SUV 4.0 threshold. MTV, SUVmax, and TLG values were obtained from each VOI. Total MTV (tMTV) was calculated by summing the MTV values in all VOIs, and similarly, total TLG (tTLG) was obtained by summing the TLG values. The distance between the centers of the lesions was noted as Dmax, and the distance between the outermost voxels of the lesions as DmaxVox. tMTV/DmaxVox was calculated by dividing the tMTV value by the DmaxVox value, and tTLG/DmaxVox was calculated by dividing the tTLG value by the DmaxVox value. The correlation of pretreatment PET parameters with response groups (complete/poor) and relapse/progression status (stable/progressive) was statistically evaluated. A total of 52 patients were included in the study. Bulky disease, tMTV, tTLG, and tMTV/DmaxVox values were found to be significantly higher in the poor response group. tMTV > 190.60 ml was found to be the only prognostic factor predicting interim PET response. The tMTV/DmaxVox and tTLG/DmaxVox showed statistically significant differences between the groups with and without progression. tMTV/DmaxVox > 7.70 was found to be the only prognostic factor in predicting relapse/progression. The evaluation of tumor burden and dissemination together in 18F-FDG PET/CT before treatment in patients with HL can help us to predict the results of the patients.