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1.
Eur Radiol ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143245

RESUMEN

OBJECTIVES: This retrospective study aimed to compare the average glandular dose (AGD) per acquisition in breast biopsies guided by contrast-enhanced mammography (CEM), conventional stereotactic breast biopsy (SBB), and digital breast tomosynthesis (DBT). The study also investigated the influence of compressed breast thickness (CBT) and density on AGD. Furthermore, the study aimed to estimate the AGD per procedure for each guidance modality. METHODS: The study included 163 female patients (mean age 57 ± 10 years) who underwent mammography-guided biopsies using SBB (9%), DBT (65%), or CEM (26%) guidance. AGD and CBT data were extracted from DICOM headers, and breast density was visually assessed. Statistical analyses included two-sample t-tests and descriptive statistics. RESULTS: Mean AGD per acquisition varied slightly among CEM (1.48 ± 0.22 mGy), SBB (1.49 ± 0.40 mGy), and DBT (1.55 ± 0.47 mGy), with CEM presenting higher AGD at lower CBTs and less dose escalation at higher CBTs. For CBT > 55 mm, CEM showed reduced AGD compared to SBB and DBT (p < 0.001). Breast density had minimal impact on AGD, except for category A. The estimated AGD per procedure was approximately 11.84 mGy for CEM, 11.92 mGy for SBB, and 6.2 mGy for DBT. CONCLUSION: The study found mean AGD per acquisition to be similar for CEM and SBB, with DBT slightly higher. CEM demonstrated higher AGD at lower CBT but lower AGD at higher CBT, indicating reduced dose escalation with increasing thickness. While breast density had minimal overall impact, variations were noted in category A. DBT was more dose-efficient per procedure due to fewer acquisitions required. CLINICAL RELEVANCE STATEMENT: CEM guidance provides effective lesion visualization within safe radiation limits, improving the precision of percutaneous image-guided breast interventions and supporting its potential consideration in a wider range of breast diagnostic procedures. KEY POINTS: Limited data exist on the AGD using CEM guidance for breast biopsies. CEM and SBB exhibit similar AGD per acquisition; DBT demonstrated the lowest AGD per procedure. Radiation from CEM guidance fits within safe limits for percutaneous image-guided breast interventions.

2.
Nanomaterials (Basel) ; 14(14)2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39057857

RESUMEN

This work discusses the applicability of lightweight aggregate-encapsulated n-octadecane with 1.0 wt.% of Cu nanoparticles, for enhanced thermal comfort in buildings by providing thermal energy storage functionality to no-fines concrete. A straightforward two-step procedure (impregnation and occlusion) for the encapsulation of the nano-additivated phase change material in lightweight aggregates is presented. Encapsulation efficiencies of 30-40% are achieved. Phase change behavior is consistent across cycles. Cu nanoparticles provide nucleation points for phase change and increase the rate of progression of phase change fronts due to the enhancement in the effective thermal conductivity of n-octadecane. The effective thermal conductivity of the composites remains like that of regular lightweight aggregates and can still fulfil thermal insulation requirements. The thermal response of no-fines concrete blocks prepared with these new aggregates is also studied. Under artificial sunlight, with a standard 1000 W·m-2 irradiance and AM1.5G filter, concrete samples with the epoxy-coated aggregate-encapsulated n-octadecane-based dispersion of Cu nanoparticles (with a phase change material content below 8% of the total concrete mass) can effectively maintain a significant 5 °C difference between irradiated and non-irradiated sides of the block for ca. 30 min.

3.
Nanoscale ; 16(17): 8470-8478, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38590267

RESUMEN

Transition metal dichalcogenides, including WSe2, have gained significant attention as promising nanomaterials for various applications due to their unique properties. In this study, we explore the temperature-dependent photoluminescent properties of WSe2 nanomaterials to investigate their potential as luminescent nanothermometers. We compare the performance of WSe2 quantum dots and nanorods synthesized using sonication synthesis and hot injection methods. Our results show a distinct temperature dependence of the photoluminescence, and conventional ratiometric luminescence thermometry demonstrates comparable relative thermal sensitivity (0.68-0.80% K-1) and temperature uncertainty (1.3-1.5 K), irrespective of the morphology of the nanomaterials. By applying multiple linear regression to WSe2 quantum dots, we achieve enhanced thermal sensitivity (30% K-1) and reduced temperature uncertainty (0.1 K), highlighting the potential of WSe2 as a versatile nanothermometer for microfluidics, nanofluidics, and biomedical assays.

4.
Heliyon ; 9(6): e16775, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37292308

RESUMEN

Perovskite-type materials have attracted great attention in recent times due to their interesting characteristics, such as their luminescent properties. The good photoluminescence quantum yields as well as the possibility of tuning the emission wavelength has allowed the study of these materials in several applications, such as sensors or LEDs. As sensors, making nanocrystals of these perovskites emitting in the near infrared (NIR) would open the possibility of using these materials in biomedical applications. In the present work, Pd-doped CsPbBr3 perovskite nanocrystals (NCs) were synthesized and characterized. We show here Pd-doped NCs synthesized emit in NIR, at about 875 nm, using a laser emitting at 785 nm as the excitation source. This result is really new and promising, because it opens the possibility of using these nanocrystals in many applications as sensor in the field of nanobiomedicine in the future.

5.
Chem Mater ; 35(11): 4435-4448, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37332680

RESUMEN

This work reports on an alternative and advantageous procedure to attain VO2-based thermochromic coatings on silicon substrates. It involves the sputtering of vanadium thin films at glancing angles and their subsequent fast annealing in an air atmosphere. By adjusting thickness and porosity of films as well as the thermal treatment parameters, high VO2(M) yields were achieved for 100, 200, and 300 nm thick layers treated at 475 and 550 °C for reaction times below 120 s. Comprehensive structural and compositional characterization by Raman spectroscopy, X-ray diffraction, and scanning-transmission electron microscopies combined with analytical techniques such as electron energy-loss spectroscopy bring to the fore the successful synthesis of VO2(M) + V2O3/V6O13/V2O5 mixtures. Likewise, a 200 nm thick coating consisting exclusively of VO2(M) is also achieved. Conversely, the functional characterization of these samples is addressed by variable temperature spectral reflectance and resistivity measurements. The best results are obtained for the VO2/Si sample with changes in reflectance of 30-65% in the near-infrared at temperatures between 25 and 110 °C. Similarly, it is also proven that the achieved mixtures of vanadium oxides can be advantageous for certain optical applications in specific infrared windows. Finally, the features of the different structural, optical, and electrical hysteresis loops associated with the metal-insulator transition of the VO2/Si sample are disclosed and compared. These remarkable thermochromic performances hereby accomplished highlight the suitability of these VO2-based coatings for applications in a wide range of optical, optoelectronic, and/or electronic smart devices.

6.
Gland Surg ; 12(2): 140-151, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36915822

RESUMEN

Background: Some studies suggested that the patients included in the Z0011 trial may represent patients with ultrasound-negative axillary nodes and axillary invasion diagnosed by sentinel node (SN) biopsy. Nevertheless, the National Comprehensive Cancer Network (NCCN) guidelines recommend SN mapping if 1 or 2 suspicious lymph nodes are identified on axillary ultrasound (AU). The aim of this preliminary phase of the Multimodal Targeted Axillary Surgery (MUTAS) trial was to establish the accuracy of SN mapping in patients with axillary involvement undergoing upfront surgery. Methods: Between September 2019 and March 2022, we recruited patients with biopsy-proven metastatic axillary nodes and upfront surgery from a single center. We performed SN mapping in these patients before the surgical intervention, which included axillary lymph node dissection. The biopsy-proven metastatic node, SNs and the remaining axillary nodes were excised separately. SN status was considered representative of the status of the remaining axillary nodes. We calculated the sensitivity, specificity, negative predictive value and positive predictive value of the SN, overall and in patients with palpable nodes, in those with non-palpable nodes and an AU leading to diagnosis of axillary involvement, in those with 1 or 2 suspicious nodes on AU, and in patients with a single suspicious node on AU. We evaluated clinical, imaging and pathology features as predictors of the status of the remaining axillary nodes, false-negatives, and false-positives. Results: We included 25 patients in this phase. The false-negative rate of SN mapping was 28% overall, 21.42% for patients with palpable nodes, 36.36% for patients with non-palpable nodes and an AU diagnosis of axillary involvement, 28.75% for those with 1 or 2 suspicious nodes on AU, and 15.38% in patients with a single suspicious node on AU. The negative predictive value was highest in patients with a single suspicious node on AU (75%). The only significant predictive factor was that FN showed a higher Ki67 index score. Conclusions: In this study, SN mapping was not reliable in patients with biopsy-proven metastatic axillary nodes and upfront surgery for any of the subgroups studied. Further research should elucidate the best staging pathways in these patients to avoid premature de-escalation.

7.
Gels ; 8(10)2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36286135

RESUMEN

The design and synthesis of sol-gel silica-based hybrid materials and composites offer significant benefits to obtain innovative biomaterials with controlled porosity at the nanostructure level for applications in bone tissue engineering. In this work, the combination of robocasting with sol-gel ink of suitable viscosity prepared by mixing tetraethoxysilane (TEOS), gelatin and ß-tricalcium phosphate (ß-TCP) allowed for the manufacture of 3D scaffolds consisting of a 3D square mesh of interpenetrating rods, with macropore size of 354.0 ± 17.0 µm, without the use of chemical additives at room temperature. The silica/gelatin/ß-TCP system underwent irreversible gelation, and the resulting gels were also used to fabricate different 3D structures by means of an alternative scaffolding method, involving high-resolution laser micromachining by laser ablation. By this way, 3D scaffolds made of 2 mm thick rectangular prisms presenting a parallel macropore system drilled through the whole thickness and consisting of laser micromachined holes of 350.8 ± 16.6-micrometer diameter, whose centers were spaced 1312.0 ± 23.0 µm, were created. Both sol-gel based 3D scaffold configurations combined compressive strength in the range of 2-3 MPa and the biocompatibility of the hybrid material. In addition, the observed Si, Ca and P biodegradation provided a suitable microenvironment with significant focal adhesion development, maturation and also enhanced in vitro cell growth. In conclusion, this work successfully confirmed the feasibility of both strategies for the fabrication of new sol-gel-based hybrid scaffolds with osteoconductive properties.

8.
Eur Radiol ; 32(11): 7480-7487, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35536390

RESUMEN

OBJECTIVES: We compared the compression force, breast thickness, and glandular dose, as well as the severity of discomfort and women's experience between the patient-assisted compression (PAC) and standard compression (SC) modes. MATERIALS AND METHODS: We conducted a prospective randomized controlled study at Hospital del Mar in Barcelona, Spain. We included 448 asymptomatic women aged 50 to 69 years old, attending their screening round from December 2017 to December 2019. Mammograms included the two bilateral views. In each woman, one breast was studied with SC and the other with PAC. The mode used in each breast was selected following a randomized list. Compression force, breast thickness, and average glandular dose were obtained for each of the 1792 images. We also recorded the degree of discomfort and women's experience, after mammogram acquisitions, using a predefined survey. RESULTS: Higher compression forces were obtained with PAC than with SC (99.27 N vs 83.25 N, p < 0.001). Breast thickness mode (56.11 mm vs 57.52 mm, p = 0.015) and glandular dose (1.34 mGy vs 1.37 mGy, p = 0.018) were lower in PAC. The discomfort score was slightly higher with PAC (mean 3.94 vs 3.69, p = 0.042), but in the satisfaction survey, more women reported that PAC caused less discomfort. Additionally, 63.2% of women (289/448) preferred PAC. CONCLUSION: PAC achieved higher compression forces without impairing the other technical imaging parameters and enhanced women's experience of screening mammography. We believe there were no clinically significant differences in the severity of discomfort between the two modes. KEY POINTS: • Self-compression allows higher compression forces than the standard compression mode. • Self-compression does not affect technical imaging parameters. • Self-compression improved women's experience of screening mammography when standard compression was used on one breast and self-compression on the other.


Asunto(s)
Neoplasias de la Mama , Mamografía , Femenino , Humanos , Persona de Mediana Edad , Anciano , Mamografía/métodos , Detección Precoz del Cáncer , Método Simple Ciego , Estudios Prospectivos , Neoplasias de la Mama/diagnóstico por imagen
9.
Eur Radiol ; 32(11): 7470-7479, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35536391

RESUMEN

OBJECTIVES: Evaluate the image quality of a mammography screening device using the patient-assisted compression (PAC) compared with the standard compression (SC) mode. METHODS: This prospective within-woman, randomized controlled trial was conducted between September 2017 and December 2019. Participants were asymptomatic women aged 50 to 69 years attending their second or subsequent screening mammography round. By random assignment, one breast underwent the SC and the other breast, the PAC. Image quality was evaluated as perfect, good, moderate, or inadequate (PGMI) on 10 criteria for the craniocaudal (CC) view and 8 criteria for the mediolateral oblique (MLO) view. Pearson's chi-square test, with Yates' correction if pertinent, was performed to compare image quality between compression modes. RESULTS: A total of 444 participants were included (mean [± standard deviation] age, 60 [± 4.9] years). There were no differences in the percentages of PGMI between the PAC and SC modes for the CC view (perfect, 37% [162/444] vs 37% [163/444]; good, 1% [5/444] vs 2% [9/444]; moderate, 62% [277/444] vs 61% [271/444]; inadequate, 0% vs 0.2% [1/444]; p = .88) or for the MLO view (perfect, 53% [237/444] vs 56% [247/444]; good, 22% [99/444] vs 22% [97/444]; moderate, 23% [102/444] vs 22% [98/444]; inadequate, 1% [6/444] vs 0.5% [2/444]; p = .72). No differences were found when we stratified by laterality or when analyzed by PGMI criteria. CONCLUSION: PAC does not seem to impair mammographic image quality. Future research should focus in a daily practice setting. KEY POINTS: No differences were found in the distribution of the PGMI classification, a tool for quality assessment, between patient-assisted compression and standard compression. Similar results were found on stratification of image quality by mammographic view and breast laterality for both types of compression. None of the PGMI criteria had significantly more errors in patient-assisted compression than in standard compression.


Asunto(s)
Neoplasias de la Mama , Mamografía , Femenino , Humanos , Persona de Mediana Edad , Mamografía/métodos , Estudios Prospectivos , Neoplasias de la Mama/diagnóstico por imagen , Detección Precoz del Cáncer , Mama/diagnóstico por imagen , Hiperplasia
10.
Artículo en Inglés | MEDLINE | ID: mdl-35270331

RESUMEN

Assessing the long-term risk of breast cancer after diagnosis of benign breast disease by mammography is of utmost importance to design personalised screening strategies. We analysed individual-level data from 778,306 women aged 50-69 years with at least one mammographic screening participation in any of ten breast cancer screening centers in Spain from 1996 to 2015, and followed-up until 2017. We used Poisson regression to compare the rates of incident breast cancer among women with and without benign breast disease. During a median follow-up of 7.6 years, 11,708 (1.5%) women had an incident of breast cancer and 17,827 (2.3%) had a benign breast disease. The risk of breast cancer was 1.77 times higher among women with benign breast disease than among those without (95% CI: 1.61 to 1.95). The relative risk increased to 1.99 among women followed for less than four years, and remained elevated for two decades, with relative risk 1.96 (95% CI: 1.32 to 2.92) for those followed from 12 to 20 years. Benign breast disease is a long-term risk factor for breast cancer. Women with benign breast disease could benefit from closer surveillance and personalized screening strategies.


Asunto(s)
Neoplasias de la Mama , Enfermedad Fibroquística de la Mama , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/epidemiología , Detección Precoz del Cáncer , Femenino , Humanos , Mamografía , Tamizaje Masivo , Factores de Riesgo
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