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1.
BMC Genomics ; 25(1): 771, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39118023

RESUMEN

Prolonged or chronic social isolation has pronounced effects on animals, ranging from altered stress responses, increased anxiety and aggressive behaviour, and even increased mortality. The effects of shorter periods of isolation are much less well researched; however, short periods of isolation are used routinely for testing animal behaviour and physiology. Here, we studied how a 3 h period of isolation from a cagemate affected neural gene expression in three brain regions that contain important components of the social decision-making network, the hypothalamus, the nucleus taeniae of the amygdala, and the bed nucleus of the stria terminalis, using a gregarious bird as a model (zebra finches). We found evidence suggestive of altered neural activity, synaptic transmission, metabolism, and even potentially pain perception, all of which could create cofounding effects on experimental tests that involve isolating animals. We recommend that the effects of short-term social isolation need to be better understood and propose alternatives to isolating animals for testing.


Asunto(s)
Toma de Decisiones , Pinzones , Aislamiento Social , Animales , Aislamiento Social/psicología , Pinzones/fisiología , Masculino , Conducta Animal , Encéfalo/metabolismo , Encéfalo/fisiología , Núcleos Septales/metabolismo , Conducta Social , Amígdala del Cerebelo/metabolismo , Amígdala del Cerebelo/fisiología , Hipotálamo/metabolismo
2.
Front Microbiol ; 15: 1440065, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39149204

RESUMEN

Nanoparticles play a crucial role in the field of nanotechnology, offering different properties due to their surface area attributed to their small size. Among them, silver nanoparticles (AgNPs) have attracted significant attention due to their antimicrobial properties, with applications that date back from ancient medicinal practices to contemporary commercial products containing ions or silver nanoparticles. AgNPs possess broad-spectrum biocidal potential against bacteria, fungi, viruses, and Mycobacterium, in addition to exhibiting synergistic effects when combined with certain antibiotics. The mechanisms underlying its antimicrobial action include the generation of oxygen-reactive species, damage to DNA, rupture of bacterial cell membranes and inhibition of protein synthesis. Recent studies have highlighted the effectiveness of AgNPs against various clinically relevant bacterial strains through their potential to combat antibiotic-resistant pathogens. This review investigates the proteomic mechanisms by which AgNPs exert their antimicrobial effects, with a special focus on their activity against planktonic bacteria and in biofilms. Furthermore, it discusses the biomedical applications of AgNPs and their potential non-preparation of antibiotic formulations, also addressing the issue of resistance to antibiotics.

4.
Blood ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38996211

RESUMEN

Rondaptivan pegol (previously BT200) is a PEGylated RNA aptamer that binds to the A1 domain of VWF. Recent clinical trials demonstrated that BT200 significantly increased plasma VWF-FVIII levels by attenuating VWF clearance. The biological mechanism(s) through which BT200 attenuates in vivo clearance of VWF have not been defined. We hypothesized that BT200 interaction with the VWF-A1 domain may increase plasma VWF levels by attenuating macrophage-mediated clearance. We observed that full length- and VWF-A1A2A3 binding to macrophages, and VWF-A1 domain binding to LRP1 cluster II and cluster IV, were concentration-dependently inhibited by BT200. Additionally, full length VWF binding to LRP1 expressed on HEK293T (HEK-LRP1) cells was also inhibited by BT200. Importantly, BT200 interacts with the VWF-A1 domain in proximity to a conserved cluster of four lysine residues (K1405, K1406, K1407 and K1408). Alanine mutagenesis of this K1405-K1408 cluster (VWF-4A) significantly (p<0.001) attenuated binding of VWF to both LRP1 clusters II and IV. Furthermore, in vivo clearance of VWF-4A was significantly (p<0.001) reduced compared to wild type VWF. BT200 did not significantly inhibit binding of VWF-4A to LRP1 cluster IV or HEK-LRP1 cells. Finally, BT200 interaction with the VWF-A1 domain also inhibited binding to macrophage galactose lectin (MGL) and the SR-AI scavenger receptor. Collectively, our findings demonstrate that BT200 prolongs VWF half-life by attenuating macrophage-mediated clearance and specifically the interaction of K1405-1408 in the VWF-A1 domain with macrophage LRP1. These data support the concept that targeted inhibition of VWF clearance pathways represent a novel therapeutic approach for VWD and hemophilia A.

5.
Integr Comp Biol ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982258

RESUMEN

Trade-offs resulting from the high demand of offspring production are a central focus of many subdisciplines within the field of biology. Yet, despite the historical and current interest on this topic, large gaps in our understanding of whole-organism trade-offs that occur in reproducing individuals remain, particularly as it relates to the nuances associated with female reproduction. This volume of Integrative and Comparative Biology (ICB) contains a series of papers that focus on reviewing trade-offs from the female-centered perspective of biology (i.e., a perspective that places female reproductive biology at the center of the topic being investigated or discussed). These papers represent some of the work showcased during our symposium held at the 2024 meeting of the Society for Integrative and Comparative Biology (SICB) in Seattle, Washington. In this roundtable discussion, we use a question-and-answer format to capture the diverse perspectives and voices involved in our symposium. We hope that the dialogue featured in this discussion will be used to motivate researchers interested in understanding trade-offs in reproducing females and provide guidance on future research endeavors.

6.
Phys Imaging Radiat Oncol ; 31: 100598, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38993288

RESUMEN

Background & purpose: Magnetic resonance imaging (MRI) is increasingly used in treatment preparation of ocular proton therapy, but its spatial accuracy might be limited by geometric distortions due to susceptibility artefacts. A correct geometry of the MR images is paramount since it defines where the dose will be delivered. In this study, we assessed the geometrical accuracy of ocular MRI. Materials & methods: A dedicated ocular 3 T MRI protocol, with localized shimming and increased gradients, was compared to computed tomography (CT) and X-ray images in a phantom and in 15 uveal melanoma patients. The MRI protocol contained three-dimensional T2-weighted and T1-weighted sequences with an isotropic reconstruction resolution of 0.3-0.4 mm. Tantalum clips were identified by three observers and clip-clip distances were compared between T2-weighted and T1-weighted MRI, CT and X-ray images for the phantom and between MRI and X-ray images for the patients. Results: Interobserver variability was below 0.35 mm for the phantom and 0.30(T1)/0.61(T2) mm in patients. Mean absolute differences between MRI and reference were below 0.27 ± 0.16 mm and 0.32 ± 0.23 mm for the phantom and in patients, respectively. In patients, clip-clip distances were slightly larger on MRI than on X-ray images (mean difference T1: 0.11 ± 0.38 mm, T2: 0.10 ± 0.44 mm). Differences did not increase at larger distances and did not correlate to interobserver variability. Conclusions: A dedicated ocular MRI protocol can produce images of the eye with a geometrical accuracy below half the MRI acquisition voxel (<0.4 mm). Therefore, these images can be used for ocular proton therapy planning, both in the current model-based workflow and in proposed three-dimensional MR-based workflows.

7.
Animals (Basel) ; 14(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38998015

RESUMEN

Good zoo animal welfare is commonly promoted with environmental enrichment; however, some species are less likely to be offered enrichment than others. This study tested the effect of enrichment on a group of scarlet ibises from Zoomarine Algarve, Portugal. The study consisted of a first baseline condition, followed by four types of enrichment displays with individual presentations, a post-enrichment condition, and a post-enrichment with all enrichment types presented simultaneously. The enrichment types chosen were physical, with a tidal simulation in the lakes of the enclosure; nutritional, presenting mussels in a plastic mesh tube; sensory, by playing scarlet ibises calls; and tactile, with brushes through the habitat. The data collection was performed for 21 days between January and March 2021, 3 times a day, using scan sampling and instantaneous time sampling every 2 min. The comparison between conditions revealed that most behaviors showed similarity between the baseline and post-enrichment conditions, suggesting that after removing the enrichment, the behaviors returned to their initial baseline. It was also found that each enrichment influenced different types of behaviors and these behaviors also changed depending on the time of day. Exploratory behavior was only associated with the presence of enrichment, and vocalizations were only heard after the sensory enrichment was performed. This study demonstrates that the use of physical and tactile enrichments increased activity and decreased stationary behaviors in this group of ibises and may be used to improve their lives in zoological contexts if included in the housing and husbandry protocols.

8.
An Acad Bras Cienc ; 96(2): e20230577, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38896691

RESUMEN

The objective of this study was to evaluate the effects and economic viability of diets containing different levels of antibiotic and buriti oil (BO) on performance, carcass and cut yields, and relative weight of organs of broilers. A total of 432 one- to 42-day-old male chicks were distributed in a completely randomized experimental design with six treatments, each consisting of six replicates of 12 birds. The treatments consisted of one diet with antibiotic without BO, one diet without antibiotic (DWA) without BO, and four DWA containing increasing levels of BO (0.2, 0.4, 0.6, and 0.8%). Average weight and weight gain (WG) of broilers fed with DWA + BO were similar to those of birds fed control diet. Feed intake and feed conversion (FC) were not different among treatments. Relative weight of pancreas linearly increased in the birds fed diets containing BO. The inclusion of 0.45 and 0.40% of BO in the diets promoted the improvement of WG and FC, respectively. Cost of feed management, ratio, gross margin, and gross income did not differ among treatments. It was concluded that the inclusion of 0.45% of BO in diets without antibiotics is economically feasible and allows recovering the performance of broilers.


Asunto(s)
Alimentación Animal , Pollos , Animales , Pollos/crecimiento & desarrollo , Masculino , Aceites de Plantas/administración & dosificación , Antibacterianos/administración & dosificación , Aumento de Peso/efectos de los fármacos , Antiinfecciosos/administración & dosificación , Distribución Aleatoria
9.
Dermatol Ther (Heidelb) ; 14(3): 777-791, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38509378

RESUMEN

INTRODUCTION: Depression is one of the most disabling diseases globally, with a high disease burden that generates high direct and indirect costs. The incidence of depression is twofold higher in adult women than in men. Biological and psychosocial factors constitute the pathophysiological bases of the condition and due to the complexity of the condition, current understanding is that the "treatment strategy must be multimodal". The objective of this study was to measure the effect of introducing the frequent use of makeup on improving depressive symptoms in adult women of medium-low purchasing power METHODS: Participants with the targeted profile who did not frequently use makeup were selected and randomised to receive (test group) or not (control group) stimuli and makeup products intended for encouraging the frequent use of makeup. The Zung Depression Self-Assessment Scale was used to assess depressive symptoms, with additional assessments on self-image perception using the mirror test and salivary cortisol level. RESULTS: The results demonstrated a sustained reduction in depressive symptoms (8.3 percentage points reduction in the Average Zung Index; P < 0.05), with a significant improvement in self-image perception (25% increase in the average score obtained in the mirror test; P < 0.05) and a specific influence on salivary cortisol levels (55% reduction in salivary cortisol concentration; P < 0.05) after the first makeup application. CONCLUSION: The results show that encouraging the frequent use of makeup, a practice that can be achieved by most people and which is simple and inexpensive to implement, can contribute to effective and sustainable improvement in the well-being and mental health of a significant portion of the population.

10.
Behav Brain Res ; 465: 114956, 2024 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-38479475

RESUMEN

Epilepsy designates a group of chronic brain disorders, characterized by the recurrence of hypersynchronous, repetitive activity, of neuronal clusters. Epileptic seizures are the hallmark of epilepsy. The primary goal of epilepsy treatment is to eliminate seizures with minimal side effects. Nevertheless, approximately 30% of patients do not respond to the available drugs. An imbalance between excitatory/inhibitory neurotransmission, that leads to excitotoxicity, seizures, and cell death, has been proposed as an important mechanism regarding epileptogenesis. Recently, it has been shown that microreactors composed of platinum nanoparticles (Pt-NP) and glutamate dehydrogenase possess in vitro and in vivo activity against excitotoxicity. This study investigates the in vivo effects of these microreactors in an animal model of epilepsy induced by the administration of the GABAergic antagonist bicuculline. Male Wistar rats were administered intracerebroventricularly (i.c.v.) with the microreactors or saline and, five days later, injected with bicuculline or saline. Seizure severity was evaluated in an open field. Thirty min after behavioral measurements, animals were euthanized, and their brains processed for neurodegeneration evaluation and for neurogenesis. Treatment with the microreactors significantly increased the time taken for the onset of seizures and for the first tonic-clonic seizure, when compared to the bicuculline group that did not receive the microreactor. The administration of the microreactors also increased the time spent in total exploration and grooming. Treatment with the microreactors decreased bicuculline-induced neurodegeneration and increased neurogenesis in the dorsal and ventral hippocampus. These observations suggest that treatment with Pt-NP-based microreactors attenuates the behavioral and neurobiological consequences of epileptiform seizure activity.


Asunto(s)
Epilepsia , Nanopartículas del Metal , Fármacos Neuroprotectores , Humanos , Ratas , Animales , Masculino , Bicuculina/farmacología , Platino (Metal)/efectos adversos , Ratas Wistar , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico
13.
Gen Comp Endocrinol ; 345: 114394, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37871848

RESUMEN

The COVID-19 pandemic impacted personal and professional life. For academics, research, teaching, and service tasks were upended and we all had to navigate the altered landscape. However, some individuals faced a disproportionate burden, particularly academics with minoritized identities or those who were early career, were caregivers, or had intersecting identities. As comparative endocrinologists, we determine how aspects of individual and species-level variation influence response to, recovery from, and resilience in the face of stressors. Here, we flip that framework and apply an integrative biological lens to the impact of the COVID-19 chronic stressor on our endocrine community. We address how the pandemic altered impact factors of academia (e.g., scholarly products) and relatedly, how factors of impact (e.g., sex, gender, race, career stage, caregiver status, etc.) altered the way in which individuals could respond. We predict the pandemic will have long-term impacts on the population dynamics, composition, and landscape of our academic ecosystem. Impact factors of research, namely journal submissions, were altered by COVID-19, and women authors saw a big dip. We discuss this broadly and then report General and Comparative Endocrinology (GCE) manuscript submission and acceptance status by gender and geographic region from 2019 to 2023. We also summarize how the pandemic impacted individuals with different axes of identity, how academic institutions have responded, compile proposed solutions, and conclude with a discussion on what we can all do to (re)build the academy in an equitable way. At GCE, the first author positions had gender parity, but men outnumbered women at the corresponding author position. Region of manuscript origin mattered for submission and acceptance rates, and women authors from Asia and the Middle East were the most heavily impacted by the pandemic. The number of manuscripts submitted dropped after year 1 of the pandemic and has not yet recovered. Thus, COVID-19 was a chronic stressor for the GCE community.


Asunto(s)
COVID-19 , Endocrinología , Masculino , Humanos , Femenino , Pandemias , Ecosistema , COVID-19/epidemiología , Asia
14.
Antibiotics (Basel) ; 12(12)2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38136732

RESUMEN

The skin microbiome is crucial in maintaining skin health, and its disruption is associated with various skin diseases. Prebiotics are non-digestible fibers and compounds found in certain foods that promote the activity and growth of beneficial bacteria in the gut or skin. On the other hand, live microorganisms, known as probiotics, benefit in sustaining healthy conditions when consumed in reasonable quantities. They differ from postbiotics, which are by-product compounds from bacteria that release the same effects as their parent bacteria. The human skin microbiome is vital when it comes to maintaining skin health and preventing a variety of dermatological conditions. This review explores novel strategies that use microbiome-targeted treatments to maintain and enhance overall skin health while managing various skin disorders. It is important to understand the dynamic relationship between these beneficial microorganisms and the diverse microbial communities present on the skin to create effective strategies for using probiotics on the skin. This understanding can help optimize formulations and treatment regimens for improved outcomes in skincare, particularly in developing solutions for various skin problems.

15.
Pharmaceutics ; 15(12)2023 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-38140133

RESUMEN

OBJECTIVE: This study aimed to develop a holobiont tablet with rapid dispersibility to provide regulation of the microbiota, virucidal activity, and skin barrier protection. METHODS: A 23 factorial experiment was planned to define the best formulation for the development of the base tablet, using average weight, hardness, dimensions, swelling rate, and disintegration time as parameters to be analyzed. To produce holobiont tablets, the chosen base formulation was fabricated by direct compression of prebiotics, postbiotics, and excipients. The tablets also incorporated solid lipid nanoparticles containing postbiotics that were obtained by high-pressure homogenization and freeze-drying. The in vitro virucidal activity against alpha-coronavirus particles (CCoV-VR809) was determined in VERO cell culture. In vitro analysis, using monolayer cells and human equivalent skin, was performed by rRTq-PCR to determine the expression of interleukins 1, 6, 8, and 17, aquaporin-3, involucrin, filaggrin, FoxO3, and SIRT-1. Antioxidant activity and collagen-1 synthesis were also performed in fibroblast cells. Metagenomic analysis of the skin microbiome was determined in vivo before and after application of the holobiont tablet, during one week of continuous use, and compared to the use of alcohol gel. Samples were analyzed by sequencing the V3-V4 region of the 16S rRNA gene. RESULTS: A handrub tablet with rapid dispersibility was developed for topical use and rinse off. After being defined as safe, the virucidal activity was found to be equal to or greater than that of 70% alcohol, with a reduction in interleukins and maintenance or improvement of skin barrier gene markers, in addition to the reestablishment of the skin microbiota after use. CONCLUSIONS: The holobiont tablets were able to improve the genetic markers related to the skin barrier and also its microbiota, thereby being more favorable for use as a hand sanitizer than 70% alcohol.

16.
J Exp Biol ; 226(14)2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37458064

RESUMEN

Historically, the fields of ecoimmunology, psychoneuroimmunology and disease ecology have taken complementary yet disparate theoretical and experimental approaches, despite sharing critical common themes. Researchers in these areas have largely worked independently of one another to understand mechanistic immunological responses, organismal level immune performance, behavioral changes, and host and parasite/disease population dynamics, with few bridges across disciplines. Although efforts to strengthen and expand these bridges have been called for (and occasionally heeded) over the last decade, more integrative studies are only now beginning to emerge, with critical gaps remaining. Here, we briefly discuss the origins of these key fields, and their current state of integration, while highlighting several critical directions that we suggest will strengthen their connections into the future. Specifically, we highlight three key research areas that provide collaborative opportunities for integrative investigation across multiple levels of biological organization, from mechanisms to ecosystems: (1) parental effects of immunity, (2) microbiome and immune function and (3) sickness behaviors. By building new bridges among these fields, and strengthening existing ones, a truly integrative approach to understanding the role of host immunity on individual and community fitness is within our grasp.


Asunto(s)
Ecosistema , Psiconeuroinmunología , Ecología , Conducta de Enfermedad/fisiología , Ejercicio Físico
17.
Trends Ecol Evol ; 38(9): 799-801, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37393181

RESUMEN

An infection triggers a dramatic suite of changes in host physiology and behavior. While seemingly localized, the host response affects many other organisms, both within and beyond the boundaries of the host's body, with far-reaching ecological implications. Here, I call for more awareness and integration of those potential 'off-host' effects.

18.
Animals (Basel) ; 13(12)2023 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-37370528

RESUMEN

For professionals caring for humans or non-human animals, many joys are to be found in working towards what an individual believes to be their calling, especially as they contribute to purposeful, meaningful work consistent with and intrinsic to their own values and beliefs. However, there can be downfalls. Empathic strain, conflict between co-workers, dissatisfaction with upper management, lack of opportunities to make positive changes, limited or no access to level and experience-appropriate professional development, and other stressors are all risks carried by organisations concerned with animal welfare. In the present study, a survey on job satisfaction and workplace stressors was completed by 311 zoo and aquarium professionals working in a range of roles from junior animal care staff to curator. Respondent profiles were created using Multiple Correspondence Analysis (MCA) and four distinct clusters were identified through Hierarchical Clustering on Principal Components (HCPC), highlighting common themes in different levels of experience and in job roles regarding stressors, satisfaction, and feelings about their work and workplaces. Overall, many zoo professionals were concerned with lacking the ability to feel empowered to do their best for animal welfare, and they described a link between the staff welfare and their perceptions of the welfare of the animals they cared for. Through identifying and understanding where organisations can better support their staff it is possible to target and reduce the number of common stressors faced by zoo professionals, leading to increased staff retention, higher job satisfaction, and an improved ability to perform at their best for animal welfare.

19.
Dalton Trans ; 52(23): 8003-8019, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37223970

RESUMEN

Five dinuclear copper(I) complexes of the type [Cu{κN,κN'-5-R-NC4H2-2-C(H)N(2,6-iPr2C6H3)}]2 (1a-e; R = 2,4,6-iPr3C6H2 (a), R = 2,6-Me2C6H3 (b), R = 3,5-(CF3)2C6H3 (c), R = 2,6-(OMe)2C6H2 (d), R = CPh3 (e)) were prepared by the reaction of the respective 5-R-2-iminopyrrolyl potassium salts KLa-e and [Cu(NCMe)4]BF4 in moderate yields. These new copper(I) complexes were characterized by NMR spectroscopy, elemental analysis and, in selected cases, by single crystal X-ray diffraction and their structural and electronic features further analyzed by DFT calculations and cyclic voltammetry, respectively. X-ray diffraction studies reveal dimeric Cu structures assembled by 2-iminopyrrolyl bridging ligands adopting a transoid conformation (complexes 1a and 1d), while complexes 1c and 1e displayed a cisoid conformation of those moieties, with respect to the Cu(I) centers. Additionally, VT-1H NMR and 1H-1H NOESY NMR experiments on complexes 1a-e exhibited complex fluxional processes in solution, assigned to a conformational inversion of the respective Cu2N4C4 metallacycles in all complexes but 1c, accompanied by a cisoid-transoid isomerization in the cases of complexes 1d,e. The Cu(I) complexes were also analyzed by cyclic voltammetry, where all complexes exhibit two oxidation processes, where the first oxidation is reversible, with the exception of 1b and 1c, which also show the highest oxidation potentials. The oxidation potentials follow clear trends related to the structural parameters of the complexes, in particular the Cu⋯Cu distance and the Cu2N4C4 macrocycles torsion angles. All new 5-substituted-2-iminopyrrolyl Cu(I) complexes 1a-e served as catalysts for azide-alkyne cycloaddition (CuAAC) reactions, being able to generate the respective 1,2,3-triazole products in yields as high as 82% and turnover frequencies (TOFs) as high as 859 h-1, after optimizing the conditions. The activity, as measured by the TOF, is in accordance with the oxidation potential of the corresponding complexes, the easier the oxidation, the higher the TOF value. Complex 1-H, where R = H, proved to be a poor catalyst for the same reactions, indicating that the 5-substitution in the ligand framework is crucial in stabilizing any potential catalytic species.

20.
Radiother Oncol ; 184: 109675, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37084884

RESUMEN

BACKGROUND AND PURPOSE: Studies have shown large variations in stopping-power ratio (SPR) prediction from computed tomography (CT) across European proton centres. To standardise this process, a step-by-step guide on specifying a Hounsfield look-up table (HLUT) is presented here. MATERIALS AND METHODS: The HLUT specification process is divided into six steps: Phantom setup, CT acquisition, CT number extraction, SPR determination, HLUT specification, and HLUT validation. Appropriate CT phantoms have a head- and body-sized part, with tissue-equivalent inserts in regard to X-ray and proton interactions. CT numbers are extracted from a region-of-interest covering the inner 70% of each insert in-plane and several axial CT slices in scan direction. For optimal HLUT specification, the SPR of phantom inserts is measured in a proton beam and the SPR of tabulated human tissues is computed stoichiometrically at 100 MeV. Including both phantom inserts and tabulated human tissues increases HLUT stability. Piecewise linear regressions are performed between CT numbers and SPRs for four tissue groups (lung, adipose, soft tissue, and bone) and then connected with straight lines. Finally, a thorough but simple validation is performed. RESULTS: The best practices and individual challenges are explained comprehensively for each step. A well-defined strategy for specifying the connection points between the individual line segments of the HLUT is presented. The guide was tested exemplarily on three CT scanners from different vendors, proving its feasibility. CONCLUSION: The presented step-by-step guide for CT-based HLUT specification with recommendations and examples can contribute to reduce inter-centre variations in SPR prediction.


Asunto(s)
Terapia de Protones , Humanos , Terapia de Protones/métodos , Protones , Consenso , Fantasmas de Imagen , Tomografía Computarizada por Rayos X/métodos , Calibración
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