Contrast-enhanced breast imaging: Current status and future challenges.

BACKGROUND: Contrast-enhanced breast MRI and recently also contrast-enhanced mammography (CEM) are available for breast imaging. The aim of the current overview is to explore existing evidence and ongoing challenges of contrast-enhanced breast imaging. METHODS: This narrative provides an introduction to the contrast-enhanced breast imaging modalities breast MRI and CEM. Underlying principle, techniques and BI-RADS reporting of both techniques are described and compared, and the following indications and ongoing challenges are discussed: problem-solving, high-risk screening, supplemental screening in women with extremely dense breast tissue, breast implants, neoadjuvant systemic therapy (NST) response monitoring, MRI-guided and CEM- guided biopsy. RESULTS: Technique and reporting for breast MRI are standardised, for the newer CEM standardisation is in progress. Similarly, compared to other modalities, breast MRI is well established as superior for problem-solving, screening women at high risk, screening women with extremely dense breast tissue or with implants; and for monitoring response to NST. Furthermore, MRI-guided biopsy is a reliable technique with low long-term false negative rates. For CEM, data is as yet either absent or limited, but existing results in these settings are promising. CONCLUSION: Contrast-enhanced breast imaging achieves highest diagnostic performance and should be considered essential. Of the two contrast-enhanced modalities, evidence of breast MRI superiority is ample, and preliminary results on CEM are promising, yet CEM warrants further study.

Contrast-enhanced mammography-guided biopsy: technical feasibility and first outcomes.

OBJECTIVES: To evaluate the feasibility of contrast-enhanced mammography (CEM)-guided biopsy at Hospital del Mar, a Spanish university hospital. METHODS: We retrospectively reviewed all consecutive women with a suspicious enhancing finding eligible for CEM-guided biopsy, who were prospectively enrolled in a pre-marketing clinical validation and feasibility study (October 2019 to September 2021). CEM-guided biopsy is a stereotactic-based procedure that, by using intravenous iodinated contrast media administration and dual-energy acquisition, provides localisation of enhancing lesions. All the biopsies were performed using a vacuum-assisted device. We collected procedural characteristics (patient position and type of approach), and histopathological results. Feasibility endpoints included success (visualisation of the enhancing lesion, post-procedural biopsy changes and clip placement), procedural time, number of scout acquisitions and complications. RESULTS: A total of 66 suspicious enhancing lesions (18.0% foci, 44.0% mass, 38.0% non-mass enhancement; median size 8.5 mm) in 64 patients (median age 59 years, mostly minimal [48.4%] or mild [32.8%] background parenchymal enhancement) were referred for CEM-guided biopsy in the study period. The success rate was 63/66 (95.4%). Amongst successful procedures, patients were most frequently seated (52/63, 82.5%) and the preferred approach was horizontal (48/63, 76.2%). Median total time per procedure was 15 min. Median number of acquisitions needed before targeting was 2 (range 1-4). Complications consisted of hematoma (17/63, 27%) and vasovagal reaction (2/63, 3.2%). At histology, the malignancy rate was 25/63 (39.7%). CONCLUSION: In this first patient series, CEM-guided breast biopsy was feasible, with success and complication rates similar to those previously reported for magnetic resonance guidance. KEY POINTS: • CEM may be used to guide biopsy of enhancing lesions through a stereotactic-based procedure combined with intravenous iodinated contrast media administration and dual-energy acquisition. • In this first patient series (n = 64), the success rate of CEM-guided biopsy was above 95%, the only complications were hematoma (22.2%) and vasovagal reaction (3.2%), and median total time per procedure was 15 min. • CEM-guided biopsy is feasible and could potentially be a widely available biopsy technique for enhancing-only lesions.

Interface-inspired formulation and molecular-level perspectives on heat conduction and energy storage of nanofluids.

Aiming for the introduction of stability requirements in nanofluids processing, an interface-based three-step method is proposed in this work. It is theory-based design framework for nanofluids that aims for a minimum tension at the solid-liquid interface by adjusting the polar and dispersive components of the base fluid to meet those of disperse nanomaterial. The method was successfully tested in the preparation of aqueous nanofluids containing single-walled carbon nanotubes that resulted to be stable and to provide good thermal properties, i.e. thermal conductivity increases by 79.5% and isobaric specific heat by 8.6% for a 0.087 vol.% load of nanotubes at 70 °C. Besides, a system for these nanofluids was modelled. It was found to be thermodynamically consistent and computationally efficient, providing consistent response to changes in the state variable temperature in a classical Molecular Dynamics environment. From an analysis of the spatial components of the heat flux autocorrelation function, using the equilibrium approach, it was possible to elucidate that heat conduction through the host fluid is enhanced by phonon propagation along nanotubes longitudinal axes. From an analysis of the structural features described by radial distribution functions, it was concluded that additional heat storage arises from the hydrophobic effect.

Analysis of genetic diversity of Hyptis pectinata (L.) Poit. plants using ISSR markers.

Hyptis pectinata, popularly known as 'sambacaitá' or 'canudinho', is a medicinal and aromatic species widely used in the Brazilian Northeast. In Sergipe, the excessive extraction of natural resources may reduce the genetic variability of native plants. Thus, molecular markers have frequently been applied to the characterization of genetic diversity as the basis for germplasm conservation and breeding programs. The objective of the present study was to evaluate the genetic diversity of H. pectinata plants collected in different municipalities of the State of Sergipe using ISSR molecular markers. Thirty-four primers were tested, nine of which were selected for providing reproducible and analyzable amplification products, resulting in 67 polymorphic bands. The expected heterozygosity ranged from 0.32 to 0.45, with a mean of 0.39. Polymorphism information content was of 0.49, which classifies the markers as moderately informative. A dendrogram was constructed using unweighted pair group method with arithmetic mean, forming three clusters: Cluster I (79 plants); Cluster II (4 plants); and Cluster III (2 plants). Jaccard's similarity coefficients ranged from 0.06 to 0.98. The plants SAM-117 and SAM-119 presented greater similarity. Conversely, SAM-107 and SAM-171 were the most genetically distant. In general, H. pectinata plants collected in the State of Sergipe presented low to moderate genetic diversity.

Genetic diversity of native populations of Croton tetradenius Baill. using ISSR markers.

Brazil has about 300 Croton species in different types of vegetation. Croton tetradenius Baill., which is endemic to the Northeast region and predominant in the Caatinga vegetation, stands out among the several species of this genus. Considering the importance of knowing the genetic variability of a species, the objective of this study was to analyze the genetic diversity of the genotypes of natural populations of C. tetradenius in the State of Sergipe, using ISSR molecular markers. Forty individuals were sampled in four natural populations of the State of Sergipe, Brazil. Thirteen primers were used for DNA amplification using ISSR-PCR, totaling 77 amplified fragments, of which 94.8% were polymorphic. Results of the cluster analysis obtained by the Jaccard's similarity index, using the UPGMA method, resulted in the formation of six distinct clusters. Analysis of molecular variance (AMOVA), used to estimate the genetic variability among populations, revealed significant genetic variance (P < 0.01) between and within the studied populations, and most of the genetic diversity was found (87%) within populations. According to the Jaccard's similarity index, none of the studied plants was genetically identical. CTE210 and CTE305 presented high similarity index (0.76), while CTE105 presented low similarity index (<0.16) with all related individuals. ISSR markers were efficient and allowed the formation of a molecular profile, and had sufficient polymorphism to estimate the genetic variability between the accessions of the studied populations.

Implementation of quality systems by Mexican exporters of processed meat.

Requirements of hazard analysis and critical control points (HACCP) are becoming essential for international trade in food commodities as a safety assurance component. This research reports the level of the adoption of ISO 9000 and the HACCP system by Federal Inspection Type (TIF) pork-exporting enterprises. Implementation and operating costs are reported as well as the benefits involved in this food industry process. In Mexico, there are 97 companies classified as TIF enterprises, and 22 are registered as exporters of processed pork with the National Services for Safety and Quality and Animal Health of the Secretariat of Agriculture, Livestock, Rural Development, Fisheries and Food. Surveys were administered to 22 companies, with a 95.2% response rate. Enterprise characteristics were evaluated, as well as their operating activities. Fieldwork consisted of administering structured questionnaires to TIF exporters. All the surveyed enterprises had implemented HACCP, whereas the ISO 9000 regulation was applied in only 30%. Of total production, 75% is exported to 13 countries, and 25% goes to the Mexican market niche. Results indicate that the main factors for adopting HACCP are related to accessibility to international markets, improving quality, and reducing product quality audits by customers. The results also indicated that staff training was the most important issue. Microbiological testing was the highest cost of the operation. The main benefits reported were related to better access to international markets and a considerable reduction in microbial counts. This study shows the willingness of Mexican pork processors to implement food safety protocols for producing safe and quality products to compete in the international food trade.

On-line thermal dependence study of the main solar cell electrical photoconversion parameters using low thermal emission lamps.

This paper presents a non-conventional methodology and an instrumental system to measure the effect of temperature on the photovoltaic properties of solar cells. The system enables the direct measurement of the evolution of open-circuit voltage and short-circuit current intensity in relation to a continuously decreasing temperature. The system uses a high-intensity white light-emitting diode light source with low emissions of radiation in the infrared region of the electromagnetic spectrum, resulting in a reduced heating of the photovoltaic devices by the irradiation source itself. To check the goodness of the system and the methodology designed, several measurements were performed with monocrystalline silicon solar cells, dye-sensitized solar cells, and thin-film amorphous silicon solar cells, showing similar tendencies to those reported in the literature.

Experimental analysis and computer simulation of a methodology for laser focusing in the solar cell characterization by laser beam induced current.

This paper presents a quick methodology for focusing a laser beam on a photoactive surface based on performing a single line scan while simultaneously modifying the laser's position over the surface and the distance between the focusing lens and the active surface. The methodology was tested using the computer simulation technique. Several configurations were computer simulated by programming different experimental situations to discover the situations in which this focusing methodology would provide optimum results. The conclusions obtained from computer simulation methodology were checked by means of experimental tests using several solar cells, such as a thin-film amorphous silicon solar cell, a monocrystalline silicon solar cell, and a polycrystalline silicon solar cell. From the tests performed, we concluded that optimum focusing is achieved in systems in which the laser beam induced current signal generated by the photoactive surface has no large heterogeneities (e.g., fingers or grain boundaries), artefacts, or defects. Thus, the best results are achieved in systems where the surface of the photovoltaic device has a certain degree of homogeneity.

ZnO-based dye solar cell with pure ionic-liquid electrolyte and organic sensitizer: the relevance of the dye­oxide interaction in an ionic-liquid medium.

The use of non-volatile electrolytes and fully organic dyes are key issues in the development of stable dye-sensitized solar cells (DSCs). In this work we explore the performance of ZnO-based DSCs sensitized with an indoline derivative coded D149 in the presence of a pure ionic-liquid electrolyte. Commercial nanostructured zinc oxide and an electrolyte composed of iodine plus (1) pure 1-propyl-3-methyl imidazolium iodide (PMII) and (2) a blend of PMII with low-viscosity ionic liquids were employed to construct the devices. Without further additives, the fabricated devices exhibit remarkable short-circuit photocurrents and efficiencies under AM1.5 simulated sunlight (up to 10.6 mA cm−2, 2.9% efficiency, 1 sun, active area = 0.64 cm2) due to the high surface area of the ZnO film and the high absorptivity of the D149 dye. Impedance spectroscopy is used to characterize the devices. It is found that the addition of the low-viscosity ionic-liquid improves the transport features (leading to a better photocurrent) but it does not alter the recombination rate. The robustness of the dye­oxide interaction is tested by applying continuous illumination with a Xenon-lamp. It is observed that the photocurrent is reduced at a slow rate due to desorption of the D149 sensitizer in the presence of the ionic liquid. Exploration of alternative ionic-liquid compositions or modification of the ZnO surface is therefore required to make stable devices based on ZnO and fully organic dyes.

High resolution laser beam induced current images under trichromatic laser radiation: approximation to the solar irradiation.

A laser beam induced current (LBIC) map of a photoactive surface is a very useful tool when it is necessary to study the spatial variability of properties such as photoconverter efficiency or factors connected with the recombination of carriers. Obtaining high spatial resolution LBIC maps involves irradiating the photoactive surface with a photonic beam with Gaussian power distribution and with a low dispersion coefficient. Laser emission fulfils these characteristics, but against it is the fact that it is highly monochromatic and therefore has a spectral distribution different to solar emissions. This work presents an instrumental system and procedure to obtain high spatial resolution LBIC maps in conditions approximating solar irradiation. The methodology developed consists of a trichromatic irradiation system based on three sources of laser excitation with emission in the red, green, and blue zones of the electromagnetic spectrum. The relative irradiation powers are determined by either solar spectrum distribution or Planck's emission formula which provides information approximate to the behavior of the system if it were under solar irradiation. In turn, an algorithm and a procedure have been developed to be able to form images based on the scans performed by the three lasers, providing information about the photoconverter efficiency of photovoltaic devices under the irradiation conditions used. This system has been checked with three photosensitive devices based on three different technologies: a commercial silicon photodiode, a commercial photoresistor, and a dye-sensitized solar cell. These devices make it possible to check how the superficial quantum efficiency has areas dependent upon the excitation wavelength while it has been possible to measure global incident photon-to-current efficiency values approximating those that would be obtained under irradiation conditions with sunlight.

Local coordination of Fe(3+) in layered LiCo(1-y)Al(y)O(2) oxides determined by high-frequency electron paramagnetic resonance spectroscopy.

The local coordination of Fe(3+) spin probes in trigonal LiAl(y)Co(1-y)O(2) was studied using high-frequency electron paramagnetic resonance spectroscopy. This technique allows the determination of Fe(3+) ions in respect to axial and rhombic zero-field splitting parameters (ZFS). After the progressive replacement of Co by Al, the axial D parameter of Fe(3+) increases from +0.0548 to +0.2802 cm(-1). On the same order, the rhombic E parameter decreases. Structural information about the Fe(3+) site in layered LiAl(y)Co(1-y)O(2) oxides was based on modeling of the magnitude of the ZFS parameters by means of the Newman superposition model. It was found that the first metal coordination sphere including Co(3+) and Al(3+) ions gave rise to differentiation of the Fe(3+) dopants in respect to local trigonal and rhombic distortion. The maximum trigonal distortion for the FeO(6) octahedron was achieved when Fe(3+) spin probes were surrounded by Al only, while the Co environment yields a rhombic distortion of the FeO(6) octahedron.

A quantum-chemical picture of hemoglobin affinity.

Understanding the molecular mechanism of hemoglobin cooperativity remains an enduring challenge. Protein forces that control ligand affinity are not directly accessible by experiment. We demonstrate that computational quantum mechanics/molecular mechanics methods can provide reasonable values of ligand binding energies in Hb, and of their dependence on allostery. About 40% of the binding energy differences between the relaxed state and tense state quaternary structures result from strain induced in the heme and its ligands, especially in one of the pyrrole rings. The proximal histidine also contributes significantly, in particular, in the alpha-chains. The remaining energy difference resides in protein contacts, involving residues responsible for locking the quaternary changes. In the alpha-chains, the most important contacts involve the FG corner, at the "hinge" region of the alpha(1)beta(2) quaternary interface. The energy differences are spread more evenly among the beta-chain residues, suggesting greater flexibility for the beta- than for the alpha-chains along the quaternary transition. Despite this chain differentiation, the chains contribute equally to the relaxed substitute state energy difference. Thus, nature has evolved a symmetric response to the quaternary structure change, which is a requirement for maximum cooperativity, via different mechanisms for the two kinds of chains.

Evaluation of Neospora caninum and Toxoplasma gondii infections in alpaca (Vicugna pacos) and llama (Lama glama) aborted foetuses from Peru.

The aim of this study was to investigate the participation of Neospora caninum and Toxoplasma gondii in abortion cases of Peruvian llamas and alpacas. Fifteen aborted foetuses were recovered from two main rearing areas of camelids in Peru (Central or South Andean region). Foetal histopathology was used to detect the presence of protozoal-associated lesions in target organs. N. caninum and T. gondii infections were confirmed by immunohistochemistry (IHC) combined with PCR and by PCR alone, respectively. The influence of the species (llama and alpaca), foetal age (first, second and third gestational periods) and geographical location (Central or South Andean region) of the foetuses was also studied. Thirteen of the samples (26%, 13/50) showed lesions suggestive of protozoal infection. N. caninum infection was detected by either IHC or specific PCR in 14 out of 50 foetuses (28%), of which 8 also showed protozoal-associated lesions. T. gondii DNA was not detected in any of the foetuses analysed. Protozoal infection was more frequent in the foetuses from the second gestational period (P<0.05, Fisher F-test). No significant association was observed between protozoal infection and species or geographical location (P>0.05, chi2 test). The results of the present study indicate that neosporosis should be included during the differential diagnosis of abortion in llamas and alpacas.

Multicriteria evaluation tools to support the conceptual design of activated sludge systems.

During the past decade the pressure of the whole spectrum of stakeholders has increased considerably leading the consideration of different types of objectives, i.e. economical, technical, legal and environmental, into the process design efforts. Thus, the traditional design approaches should turn into more complex assessment methods including different types of objectives in order to conduct integrated assessments. The objective of this paper is to present and discuss the usefulness of three evaluation tools, based on multicriteria decision analysis, to support the conceptual design of activated sludge systems These support tools consist of: i) preliminary multiobjective optimization, where the most promising options (those located near to the optimum) are compared based on the results of dynamic simulation, ii) identification of strong and weak points for each option by means of classification trees and the subsequent extraction of knowledge-based rules, and iii) evaluation of the trade-offs between a certain evaluation criteria and the overall process performance through the integrated application of mathematical modelling and qualitative knowledge extracted during the design process.

Incontinencia urinaria de esfuerzo en la mujer. Comparación de la técnica de Raz y de la técnica de Bologna / Comparison of Raz bladder neck suspension and the Bologna procedure for the treatment of urinary stress incontinence

Nuestra situación es la de comparar las complicaciones y los resultados sobre la incontinencia de esfuerzo de 2 técnicas de suspensión cervicouretral: la técnica de Raz y la técnica de Bologna. Se ha evaluado retrospectivamente a 199 pacientes que se han beneficiado de un tratamiento de incontinencia urinaria de esfuerzo, bien mediante la técnica de Bologna (grupo 1, 99 pacientes), bien por la técnica de Raz (grupo 2, 100 pacientes). Los datos clínicos preoperatorios, los parámetros urodinámicos y las complicaciones postoperatorias se han comparado en cada uno de los 2 grupos. El margen entre el tratamiento de la incontinencia urinaria y la recidiva se ha comparado con los 2 grupos por un test logarítmico. Se fabricó un modelo multivariante con la ayuda de un modelo de Cox, a fin de exponer los parámetros explicativos del fracaso quirúrgico. La duración de la curación en el grupo 1 es significativamente más larga que en el grupo 2 (p = 0,00001). La mediana de duración del intervalo libre sin incontinencia (éxito) es de 51 meses en el grupo 1 y de 21 meses en el 2 (p = 0,00001). La frecuencia de las complicaciones operatorias (lesión vesical y hemorragia) y postoperatorias (hemorrágicas, infecciosas y embólicas) no difieren en los 2 grupos. El análisis multivariante según el modelo de Cox muestra que la única variable preoperatoria explicativa de las recidivas es la técnica de colposuspensión realizada: Raz y Bologna. Después de este estudio comparativo, la técnica de Bologna debe preferirse a la de Raz para tratar los pacientes con IUE por el hecho de la presencia de suficiente pared vaginal anterior para confeccionar las cinchas vaginales. Si tal no es el caso, la técnica de Raz, tal y como nosotros la habíamos practicado, se debe abandonar en beneficio de otros métodos de colposuspensión (AU)

The aim of this study was to evaluate and compare perioperative morbidity and the long-term results of Raz colposuspension and the Bologna procedure in the treatment of urinary stress incontinence in women. Data from 199 women who underwent either the Bologna procedure (group 1; n = 99) or Raz colposuspension (group 2; n =100) for urinary stress incontinence were retrospectively analyzed. Preoperative clinical data, urodynamic parameters and postoperative complications were compared between the two groups. Logarithmic analysis was used to compare time to recurrence of stress incontinence between the two groups. Multivariate analysis using a Cox proportional hazards regression model was performed to identify possible outcome predictors. The success rate was significantly higher in group 1 than in group 2 (p = 0.00001). The median incontinence- free interval was 51 months in group 1 and was 21 months in group 2 (p = 0.00001). No differences were found between the two groups in the frequency of intraoperative complications (inadvertent cystotomy, hemorrhage) and postoperative complications (hemorrhagic, infectious and embolic complications). Multivariate analysis using the Cox regression model showed that the only variable correlated with the surgical cure rate was the type of surgical anti-incontinence procedure adopted: Bologna or Raz (p = 0.00001). The results of this study indicate that the Bologna procedure should be preferred over Raz colposuspension in the treatment of urinary stress incontinence when sufficient anterior vaginal tissue is available to create vaginal bands. When this is not the case, Raz colposuspension, as performed in the present study, should be abandoned in favor of other colposuspension methods (AU)

Iniencefalia / Iniencephaly

La iniencefalia es una malformación rara de la charnela cervicooccipital, de pronóstico grave. Pertenece al espectro de anomalías del cierre del tubo neural. En la actualidad se han documentado 200 casos en la literatura científica. El diagnóstico, desde ahora posible mediante la ecografía morfológica, justifica proponer a la pareja la posible interrupción de la gestación. Aportamos tres nuevos casos, recogidos entre 1990 y 2000, y revisamos las publicaciones dedicadas a esta malformación. También se describe el caso de una paciente cuyo diagnóstico temprano de iniencefalia a las 13 semanas de amenorrea permitió realizar una interrupción voluntaria del embarazo al término de la semana 14 (AU)

Iniencephaly is a rare malformation of the base of the skull and prognosis is almost invariably lethal. This entity belongs to the group of neural tube closure defects. To date, 2000 reports have been published in the literature. Diagnosis can now be made using ultrasound morphology examination, allowing pregnancy termination to be proposed. We report 3 cases of iniencephaly diagnosed between 1990 and 2000 and review the literature on this malformation. We describe the case of a patient in whom early ultrasonographic diagnosis of iniencephaly at 13 weeks of gestation allowed induced abortion at 14 weeks (AU)

Síndrome de Munchausen y gestación / Syndrome of Munchausen and pregnancy

Las metrorragias en el tercer trimestre de la gestación que parecen un cuadro de placenta previa pueden corresponder a una llamada de atención del paciente hacia el médico. Esta situación clínica nace de alteraciones facticias que permiten al paciente adoptar el papel de enfermo. Ello puede conducir a una intervención quirúrgica inútil: cesárea por metrorragias, por ejemplo. La principal dificultad de la situación es diagnóstica. El tratamiento está basado en la psicoterapia, dirigida a mejorar la relación ulterior madre-hijo y puede prevenir actos de automutilación (AU)

Metrorrhagia during the third trimester of pregnancy, simulating placenta previa, may be a sign of the patient calling for help to the doctor. This clinical situation is one where the woman mimics an illness, in order to play the role of sick patient. The risk is that this may lead to unnecessary surgical procedures, in this case caesarean section. The main difficulty in caring for these patients is to make the diagnosis. Treatment is based on psychotherapy, which can contribute to an improved mother-infant relationship and perhaps prevent acts of self-mutilation (AU)

Hepatotoxicidad secundaria a fármacos de uso común / Hepatotoxicity due to commonly-used drugs

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