71 research outputs found

    Técnicas de biopsia para el diagnóstico de lesiones mamarias no palpables

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    Facing a non-palpable mammary lesion requiring a diagnostic biopsy, consideration must be given to the most suitable guiding method for obtaining the latter. Three methods are employed at present: stereotaxy (basically in cases of microcalcifications), echography (above all in the nodules), and magnetic resonance (for lesions not made visible through the previous systems). The next step is to select the most suitable biopsy technique. The most classical and reliable technique is the surgical biopsy with prior marking using a metallic harpoon, but, besides its high cost, it has the drawback of being an aggressive technique for the diagnosis of a benign pathology. Numerous systems of puncture have been developed as alternatives. Puncture with a fine needle is technically simple to carry out and can provide good results in the mammary nodules, but the existence of positive and negative false results has progressively limited its use. As an alternative, the systems of biopsy with a broad needle have made it possible to obtain multiple cylinders with a high diagnostic reliability, above all in the case of mammary nodules. However, their use in microcalcifications continues to show negative false results. The arrival of systems of vacuum-assisted biopsy has made it possible to obtain cylinders of greater quality, above all in cases of microcalcifications. Finally, the systems of percutaneous resection biopsy by means of cannulas with a diameter of 22 mm make it possible to completely extract lesions of a size below that of the cannula, with a reliability similar to that of the surgical biopsy

    Modular multilevel converter in electrified railway systems: applications of rail static frequency converters and rail power conditioners

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    The Modular Multilevel Converter (MMC) has become the most preferable multilevel converter topology for medium and high-power systems, due to the MMC's high reliability and redundancy. This paper focuses on MMC applications in electrified railway traction grids, namely, applications of rail static frequency converters and rail power conditioners. These applications provide a higher railway traction grid capacity and improve the power quality of the three-phase power grid. Simulation results of a case study are presented to show the features when using the MMC in electrified railway grids.This work has been supported by the Portuguese Foundation of Science and Technology (FCT), within the R&D Units Project Scope: UIDB/00319/2020 and PTDC/EEIEEE/28813/2017. The first author Mohamed Tanta is supported by FCT Ph.D. grant with a reference PD/BD/127815/2016

    Evaluación de la mama contralateral mediante resonancia magnética en pacientes con diagnóstico reciente de cáncer mamario unilateral

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    Breast Magnetic Resonance (BMR) imaging is a useful tool in the evaluation of breast cancer before surgical treatment. BMR imaging plays an important role in the evaluation of the extension of the malignant lesions, and the study of multifocality and multicentricity. BMR may have a role in the detection of synchronous contralateral breast cancer that is occult to conventional imaging methods (mammography and ultrasonography). In this study we review 13 series of different authors in which they have used BMR in the evaluation of the contralateral breast in patients with newly diagnosed breast cancer. Two thousand five hundred and eleven patients were evaluated with BMR and 123 contralateral cancers, that were occult to conventional methods, were detected with this technique (4,9 %). Therefore, BMR imaging of the breast is useful as a complementary tool because of its high sensitivity in local staging of a breast cancer and its ability in the detection of synchronous contralateral breast cancer in patients with newly diagnosed breast cance

    Axillary lymph node imaging in mRNA, vector-based, and mix-and-match COVID-19 vaccine recipients: ultrasound features

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    Objectives To assess ultrasound characteristics of ipsilateral axillary lymph nodes after two doses of four different COVID-19 vaccination protocols, to determine whether these parameters differed with age, and to describe how they changed on follow-up imaging. Methods A total of 247 volunteer employees from our center who had received two doses of COVID-19 vaccination were recruited and followed prospectively. Axillary ultrasound of the ipsilateral vaccinated arm was performed the week after receiving the second dose to analyze lymph node features (number, long-axis, cortical thickness, morphology, and vascular imaging). Axillary lymphadenopathy resulting from four vaccination protocols—mRNA (BNT162b2, mRNA-1273), ChAdOx1-S, and mix-and-match—was compared. Analysis was conducted using the Kruskal-Wallis test and post hoc analysis with Bonferroni corrections. Nodal reactogenicity was evaluated for two age groups: young (< 45 years old) and middle-aged ( ≥ 45 years old). All parameters were compared between both groups using an unpaired-sample Student t test. A p value < 0.05 was considered statistically significant. Results Significantly higher values for total number of visible nodes, cortical thickness, Bedi’s classification (p < 0.001), and vascularity (p < 0.05) were observed in mRNA vaccine recipients compared to full ChAdOx1-S protocol recipients. Moreover, mix-and-match protocol recipients showed greater nodal cortical thickness and higher Bedi’s classification than full ChAdOx1-S recipients (p < 0.001). Analyses between age groups revealed greater cortical thickness, Bedi’s classification, and color Doppler signal in younger patients (p < 0.05). Conclusions Nodal parameters of Bedi’s classification and cortical thickness were more often increased in mRNA and mix-andmatch vaccine recipients when compared to ChAdOx1-S vaccine alone, especially in younger patients. Key Points • Hyperplastic lymphadenopathy was observed more frequently in mRNA and mix-and-match vaccine protocols compared to full vector-based vaccination. • Higher values for cortical thickness, Bedi’s classification, and color Doppler signal parameters were identified in younger patients. • Observed lymph node findings normalized in greater than 80% of patients by the third month following vaccination

    Cáncer de mama durante el embarazo

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    As women in western countries delay childbearing, it has been hypothesized that the incidence of breast cancer diagnosed during pregnancy will increase. Breast carcinoma during pregnancy(BCP) put the health of the mother in conflict with that of the fetus. The aim is to give optimal treatment to the mother to maximise the chances of survival, whilst minimising the risk of harm of the fetus. Few breast surgeons or oncologist develop expertise in this area owing the rarity of the association. We report the epidemiology, pathology, clinical picture, therapeutic management and fetal outcome of pregnant women with breast cancer treated in our institutio

    Computer-Based Training in Math and Working Memory Improves Cognitive Skills and Academic Achievement in Primary School Children:Behavioral Results

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    Student academic achievement has been positively related to further development outcomes, such as the attainment of higher educational, employment, and socioeconomic aspirations. Among all the academic competences, mathematics has been identified as an essential skill in the field of international leadership as well as for those seeking positions in disciplines related to science, technology, and engineering. Given its positive consequences, studies have designed trainings to enhance children's mathematical skills. Additionally, the ability to regulate and control actions and cognitions, i.e., executive functions (EF), has been associated with school success, which has resulted in a strong effort to develop EF training programs to improve students' EF and academic achievement. The present study examined the efficacy of a school computer-based training composed of two components, namely, working memory and mathematics tasks. Among the advantages of using a computer-based training program is the ease with which it can be implemented in school settings and the ease by which the difficulty of the tasks can be adapted to fit the child's ability level. To test the effects of the training, children's cognitive skills (EF and IQ) and their school achievement (math and language grades and abilities) were evaluated. The results revealed a significant improvement in cognitive skills, such as non-verbal IQ and inhibition, and better school performance in math and reading among the children who participated in the training compared to those children who did not. Most of the improvements were related to training on WM tasks. These findings confirmed the efficacy of a computer-based training that combined WM and mathematics activities as part of the school routines based on the training's impact on children's academic competences and cognitive skills

    Tratamiento conservador del cáncer de mama: valoración de los resultados

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    Introducción: La asociación de cirugía limitada y radioterapia es el tratamiento de elección para un gran número de mujeres con cáncer de mama; no obstante esta opción terapéutica va asociada a un número no despreciable de recidivas sobre la mama tratada (1-1,5% por año de seguimiento). Material y Métodos: Se analizan 641 casos de mujeres con cáncer de mama, tratados mediante cirugía conservadora de la mama y radioterapia y seguidos durante una media de 50 meses. La técnica consistió preferentemente en la practica de una Resección Segmentaria de mama con vaciamiento axilar, al menos de los niveles I y II (excepto en los CIS a partir de 1997), complementada con la administración de Radioterapia (45-50 Gy sobre la mama y una sobreimpresión de 15-20 Gy). Resultados: La edad media fue de 52.3 años, con extremos en 21 y 82 años El tamaño medio tumoral fue pT: 1,7 cm y el 63,1% de los casos correspondieron a tumores pT1. En 41 casos no se realizó vaciamiento axilar (35 CIS y 6 pT1mic). En 4 casos existió afectación puntual de bordes (componente intraductal) que fueron sometidos a sobreimpresión radioterápica con 20Gy. Tras un seguimiento medio de 50 meses, el 91,4% están libres de enfermedad y en 12 casos (1,9%) se desconocía su estado. Se han producido 13 recidivas (2%) a nivel mamario (2 de ellas en un cuadrante distinto). Conclusiones: El estado de los bordes de resección en un factor fundamental en la cirugía conservadora del cáncer de mama. La resección del tumor debe ser suficientemente amplia e incluir el segmento mamario asiento del tumor, para asegurar un alto índice de control local, sin comprometer el resultado cosmético. El estudio histológico de los bordes de resección permite reducir significativamente la necesidad de una segunda cirugía.Introduction: Conservative surgery combined with radiotherapy is an effective treatment in many cases of breast cancer. Nevertheless this therapy is associated with a not inconsiderable number of recurrences in the remaining breast after excision (1-1.5% recurrences per year of follow-up). Material and Methods: We reviewed 641 cases of breast cancer (age average was 52.3 years (21-82) and tumour size average 1.7 cm, 3% corresponded to pT1 tumours) treated with conservative surgery combined with radiotherapy, average follow-up of 50 months. The technique consisted of segmentectomy and at least level I-II axilary dissection (excluding in situ carcinoma diagnosed since 1997, in which lymphadenectomy was not performed). Adjuvant radiotherapy was also indicated (giving a dose of 45-50 Gy to the breast, and another 15-20 Gy dose was given to tumour size). Results: In 41 cases lymphadenectomy was not performed (35 cases of Tis, and 6 pTmic). In 4 cases, 20 Gy radiotherapy was administered to the tumour excision site because of in situ carcinoma disease in the margins. During follow-up of 50 months, 91.4% of the patients were disease- free; in 12 cases we are not informed of the present status. 13 recurrences (2%) have been found, two of which were in a different quadrant. Conclusions: The status of the surgical margins is an important factor in the practice of conservative surgery. Tumour excision must be broad enough and must include the whole segment in which the tumour is located to obtain local control of the disease, maintaining an acceptable cosmetic appearance. The intraoperative study of specimen margins permits the reduction of cases in which a second operation is needed

    Modification of the activity of an \u3b1-amylase from Bacillus licheniformis by several surfactants

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    The influence of different commercial surfactants on the enzymatic activity of a commercial \u3b1-amylase from Bacillus licheniformis (Termamyl 300 L) has been studied. As non-ionic surfactants, alkyl polyglycosides (Glucopon\uae 215, Glucopon\uae 600 and Glucopon\uae 650) were studied, as were fatty alcohol ethoxylates (Findet 1214N/23 and Findet 10/15), and nonyl phenol ethoxylate (Findet 9Q/21.5NF). Also, an anionic surfactant, linear alkyl benzene sulfonate (LAS) was assayed. In general, none of the non-ionic surfactants studied, except Findet 10/15, vary substantially the enzymatic activity. Findet 10/15 has the strongest hydrophobic character and reduces the enzymatic activity more significantly the greater its concentration. Regarding LAS, this surfactant significantly depressed enzymatic activity, presumably due to the electrostatic interactions caused by its anionic character

    Detection of high cardiovascular risk patients with ankylosing spondylitis based on the assessment of abdominal aortic calcium as compared to carotid ultrasound

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    ABSTRACT: Background: This study aimed to determine whether, besides carotid ultrasound (US), a lateral lumbar spine radiography may also help identify ankylosing spondylitis (AS) patients at high risk of cardiovascular (CV) disease. Methods: A set of 125 AS patients older than 35 years without a history of CV events, diabetes mellitus, or chronic kidney disease was recruited. Carotid US and lateral lumbar spine radiography were performed in all of them. The CV risk was calculated according to the total cholesterol systematic coronary risk evaluation (TC- CORE) algorithm. Presence of carotid plaques was defined following the Mannheim Carotid Intima-media Thickness and Plaque Consensus. Abdominal aortic calcium (AAC) in a plain radiography was defined as calcific densities visible in an area parallel and anterior to the lumbar spine. Results: Carotid US showed higher sensitivity than lateral lumbar spine radiography to detect high CV risk in the 54 patients with moderate TC-SCORE (61% versus 38.9%). Using carotid plaques as the gold standard test, a predictive model that included a TC-SCORE >= 5% or the presence of AAC in the lateral lumbar spine radiography in patients with both moderate and low CV risk (< 5%) according to the TC-SCORE yielded a sensitivity of 50.9% with a specificity of 95.7% to identify high/very high CV-risk AS patients. A positive correlation between AAC and carotid plaques was observed (r2 = 0.49, p < 0.001). Conclusions: A lateral lumbar spine radiography is a useful tool to identify patients with AS at high risk of CV disease
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