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Microwaves can safely and non-destructively illuminate and penetrate dielectric materials, making them an attractive solution for various medical tasks, including detection, diagnosis, classification, and monitoring. Their inherent electromagnetic properties, portability, cost-effectiveness, and the growth in computing capabilities have encouraged the development of numerous microwave sensing and imaging systems in the medical field, with the potential to complement or even replace current gold-standard methods. This review aims to provide a comprehensive update on the latest advances in medical applications of microwaves, particularly focusing on the near-field ones working within the 1-15 GHz frequency range. It specifically examines significant strides in the development of clinical devices for brain stroke diagnosis and classification, breast cancer screening, and continuous blood glucose monitoring. The technical implementation and algorithmic aspects of prototypes and devices are discussed in detail, including the transceiver systems, radiating elements (such as antennas and sensors), and the imaging algorithms. Additionally, it provides an overview of other promising cutting-edge microwave medical applications, such as knee injuries and colon polyps detection, torso scanning and image-based monitoring of thermal therapy intervention. Finally, the review discusses the challenges of achieving clinical engagement with microwave-based technologies and explores future perspectives.

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The lipid layer surrounding the vitelline membrane of insect eggs has a critical role in the waterproofing and desiccation resistance of embryos. However, this lipid layer also prevents the flux of chemicals into the embryos, such as cryoprotectants, which are required for successful cryopreservation. The permeabilization studies of silkworm embryos remain insufficient. Therefore, in this study, we developed a permeabilization method to remove the lipid layer in the silkworm, Bombyx mori, and examined factors affecting the viability of dechorionated embryos, including the types and exposure times of chemicals and embryonic stages. Among the chemicals used, hexane and heptane were effective for permeabilization, whereas Triton X-100 and Tween-80 were less effective. Regarding the embryonic stages, there were significant differences between 160 and 166 h after egg laying (AEL) at 25 °C. Consequently, we found that the treatment of 160 AEL embryos with hexane for 30 s was the best condition for the permeability and viability of embryos, in which over 62% of the permeabilized embryos grew up to the second larval instar and their moths could lay fertilized eggs. Our method can be used for various purposes, including permeability investigations using other chemicals and embryonic cryopreservation.

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The chorion covering/protecting insect egg, which has some effective functions such as providing mechanical strength, protecting eggs from external environments, and keeping moisture adjustment, is one of the principal barriers to manipulation, cryopreservation, and study of insect embryos. Here we evaluated the silkworm embryo viability after dechorionation using chemical reagents. We have developed an easy and effective method for chemical dechorionation that enables embryos to develop in culture, so that the larvae could normally grow. Eggs attached to a nylon net were treated with potassium hydroxide (KOH) and sodium hypochlorite (NaClO) to remove the chorion, washed with the Grace's insect medium, and then cultured using a dry-moist method which we created. The most effective treatment with regard to embryonic development, hatching, and production of second instar larvae was 30% KOH for 7 min and 2% NaClO for 5 min at 27 °C. Embryos at later embryonic stages were more tolerant to chemical dechorionation and over 75% of embryos treated at 168 h-old (Stage 25, appearance of taenidium) survived to the second larval instar, moreover, the larvae derived from the dechorionated embryos have developed into the moths which can lay the fertilized eggs. Our method would contribute to the establishment of cryopreservation using embryos and analysis of silkworm embryogenesis and might also be applicable to other insect species.

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This paper experimentally validates the capability of a microwave prototype device to localize hemorrhages and ischemias within the brain as well as proposes an innovative calibration technique based on the measured data. In the reported experiments, a 3-D human-like head phantom is considered, where the brain is represented either with a homogeneous liquid mimicking brain dielectric properties or with ex vivo calf brains. The microwave imaging (MWI) system works at 1 GHz, and it is realized with a low-complexity architecture formed by an array of twenty-four printed monopole antennas. Each antenna is embedded into the "brick" of a semi-flexible dielectric matching medium, and it is positioned conformal to the head upper part. The imaging algorithm exploits a differential approach and provides 3-D images of the brain region. It employs the singular value decomposition of the discretized scattering operator obtained via accurate numerical models. The MWI system analysis shows promising reconstruction results and extends the device validation.

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The pterostilbene (PT) molecule is a phytoalexin with a reducing effect on reactive oxygen species (ROS) and with a capacity to block lipogenesis. However, the potential reducing effects of PT on equatorial lipid accumulation and ROS have not yet been elucidated for in vitro-derived bovine embryos. The present study evaluated the effects of concentrations of 3, 1, 0.33, 0.11 µM PT, and a vehicle group on the percentage of cleaved embryos, embryos with more than 6 cells, percentage of blastocyst on Day 7 and 8, percentage of transferable embryos on Day 7, the cell count and relative concentration of lipids. In the second experiment, the effects of 0.33 µM PT and a vehicle group within two different O2 environments (5% and 20%) were evaluated for ROS generation and the percentage of Day 8 blastocysts. In the first experiment, no significant differences were found between the treatments with PT and the vehicle group (p > .05) concerning the percentage of cleaved embryos and embryos with more than 6 cells. Lipid reduction was observed in the groups treated with PT versus the vehicle group (p < .05). The vehicle group showed a higher rate of blastocyst production on Days 7 and 8 (p < .05) and an increase in the percentage of transferable embryos on Day 7 compared to the PT treatment groups (p < .05). Cell counts were not significantly different between treatments with PT and the vehicle group (p > .05). In the second experiment, the O2 concentration did not significantly affect ROS generation (p > .05); however, the groups treated with PT (0.33 µM) had a reduction in ROS (p < .05). The O2 concentration also did not significantly affect the rate of blastocyst production on Day 8 (p = .7696). Future research should be conducted to ascertain whether the reduction of lipids could enhance the cryopreservation and post-thaw viability of PT-treated embryos.

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This work focuses on brain stroke imaging via microwave technology. In particular, the open issue of monitoring patients after stroke onset is addressed here in order to provide clinicians with a tool to control the effectiveness of administered therapies during the follow-up period. In this paper, a novel prototype is presented and characterized. The device is based on a low-complexity architecture which makes use of a minimum number of properly positioned and designed antennas placed on a helmet. It exploits a differential imaging approach and provides 3D images of the stroke. Preliminary experiments involving a 3D phantom filled with brain tissue-mimicking liquid confirm the potential of the technology in imaging a spherical target mimicking a stroke of a radius equal to 1.25 cm.

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Gastrointestinal stromal tumors (GISTs) are rare neoplasms of the gastrointestinal tract associated with high rates of malignant transformation. Most GISTs present asymptomatically. They are best identified by computed tomography (CT) scan and most stain positive for CD117 (C-Kit), CD34, and/or DOG-1. There have been many risk stratification classifications systems which are calculated based on tumor size, mitotic rate, location, and perforation. The approaches to treating GISTs are to resect primary low-risk tumors, resect high-risk primary or metastatic tumors with imatinib 400 mg daily for 12 months, or if the tumor is unresectable, neoadjuvant imatinib 400 mg daily followed by surgical resection is recommended. Sunitinib is required for KIT exon 9, 13, and 14 mutations, while ponatinib is used for exon 17 mutations and regorafenib for highly refractory tumors. High-risk tumors should be monitored for recurrence with serial abdominal CT scans. Radiofrequency ablation has shown to be effective when surgery is not suitable. Newer therapies of ipilimumab, nivolumab, and endoscopic ultrasound alcohol ablation have shown promising results. This report addresses the epidemiology, clinical presentation, diagnostic imaging, histologic diagnosis, classification and risk stratification, staging and grading, surgical treatment, adjuvant treatment, and metastasis of GISTs.

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ABSTRACT Objective: The objective of this study is to present demographic data on the occurrence of spinal metastases in the service where the work was performed and to investigate the reliability of the modified Tokuhashi score in the decision making in patients with metastatic spinal cancer. Methods: We conducted a review of medical records of all cases of vertebral bone metastasis, confirmed by anatomopathological examination, from January 2009 to June 2012. Data review included demographic details, origin of the primary cancer, duration of symptoms, localization of metastases, Karnofsky performance scale and survival based on modified Tokuhashi score. We divided patients into three groups. Group A included patients with life expectancy of less than six months, group B included patients with life expectancy of between six and 12 months, and group C included patients with a life expectancy of more than 12 months. We compared the calculated survival with the current survival in the three groups with all patients followed-up to a minimum of 1 year or until death. Results: The predict survival in group A was 63.6% according to the modified Tokuhashi score, albeit group B had only 30% agreement. Conclusions: For patients in group A, the agreement rate of patient survival was better (63.4%) than that observed in patients in group B (30%). Our sample had no patient classified as group C.

RESUMO Objetivo: O objetivo do trabalho é apresentar dados demográficos sobre a ocorrência de metástases na coluna vertebral no serviço onde o trabalho foi realizado e investigar a confiabilidade do escore modificado de Tokuhashi no processo de decisão em pacientes com câncer metastático na coluna. Métodos: Realizamos uma revisão de prontuários de todos os casos de metástase óssea vertebral, confirmadas por exame anatomopatológico, no período de janeiro de 2009 a junho de 2012. A revisão de dados incluiu detalhes demográficos, origem do câncer primário, duração dos sintomas, localização das metástases, escala de performance de Karnofsky e cálculo da sobrevida com base no escore modificado de Tokuhashi. Dividimos os pacientes em três grupos. O grupo A incluiu pacientes com expectativa de vida menor do que seis meses, grupo B incluiu pacientes com expectativa de vida entre seis e 12 meses e grupo C incluiu pacientes com expectativa de vida maior que 12 meses. Comparamos a sobrevida calculada com a atual sobrevida nos três grupos, com todos pacientes acompanhados até o mínimo de um ano ou até a morte. Resultados: A sobrevida prevista nos pacientes do grupo A foi de 63,6% de acordo com o escore modificado de Tokuhashi, contudo pacientes do grupo B tiveram apenas 30% de concordância. Conclusões: Para pacientes do grupo A, a taxa de concordância da sobrevida dos pacientes foi melhor (63,4%) que o observado em pacientes do grupo B (30%). Nossa amostra não teve nenhum paciente classificado como do grupo C.

RESUMEN Objetivo: El objetivo de este estudio es presentar datos demográficos sobre la aparición de metástasis en la columna vertebral en el servicio donde se realizó el trabajo e investigar la fiabilidad de la escala modificada de Tokuhashi en la toma de decisiones en pacientes con cáncer metastásico en la columna vertebral. Métodos: Se realizó una revisión retrospectiva de todos los casos de metástasis ósea vertebral, confirmados por examen histopatológico, de enero 2009 a junio de 2012. La revisión de los datos incluyó datos demográficos, origen del cáncer primario, duración de los síntomas, localización de las metástasis, escala de rendimiento de Karnofsky y el cálculo de la supervivencia basado en la escala modificada de Tokuhashi. Dividimos a los pacientes tres grupos. El grupo A incluyó pacientes con una esperanza de vida inferior a 6 meses, el grupo B incluyó pacientes con una esperanza de vida de entre seis y 12 meses y el grupo C incluyó pacientes con esperanza de vida superior a 12 meses. Se comparó la supervivencia calculada con la supervivencia actual en los tres grupos, con todos los pacientes seguidos a un mínimo de un año o hasta la muerte. Resultados: La supervivencia esperada en el grupo A fue de 63,6%, según la escala modificada de Tokuhashi, pero los pacientes del grupo B tenían sólo un 30% de concordancia. Conclusiones: En los pacientes del grupo A, la tasa de concordancia de la supervivencia del paciente fue mejor (63,4%) que la observada en el grupo de pacientes en el grupo B (30%). En nuestra muestra no había ningún paciente clasificado como grupo C.

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OBJECTIVE: To investigate the percentage of ideal patients who would be eligible for hip-resurfacing surgery at a reference service for hip arthroplasty. METHODS: Out of all the cases of hip arthroplasty operated at Hospital do Servidor Público Estadual de São Paulo (HSPE) between January 2009 and December 2010, we assessed a total of 592 procedures that would fit the criteria for indication for resurfacing arthroplasty, after clinical and radiological evaluation according to the criteria established by the Food and Drug Administration (FDA) and by Seyler et al. RESULTS: Among the total number of hip replacement arthroplasty cases, 5.74% of the patients were eligible. Among the patients who underwent primary arthroplasty, we found that 8.23% presented ideal conditions for this procedure. CONCLUSION: The study demonstrated that this type of surgery still has a limited role among hip surgery methods.

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OBJETIVO: Verificar a porcentagem de pacientes ideais elegíveis à cirurgia do tipo resurfacing do quadril em um serviço referência de artroplastias do quadril. MÉTODOS: Analisamos, dentre todos os casos de artroplastia do quadril realizadas no Hospital do Servidor Público Estadual de São Paulo (HSPE) entre janeiro de 2009 e dezembro de 2010, um total de 592 artroplastias, as quais se enquadrariam nos critérios de indicação ideal para artroplastia de resurfacing segundo avaliação clínica e radiológica preconizada com os critérios estabelecidos pela Food and Drug Administration (FDA) e por Seyler et al. RESULTADOS: Considerando o universo total das artroplastias de substituição do quadril, foram elegíveis 5,74% dos pacientes. Nos pacientes submetidos à artroplastia primária, encontrou-se 8,23% em condições ideais a este procedimento. CONCLUSÃO: Demonstra-se o papel ainda restrito desta modalidade cirúrgica entre as cirurgias do quadril.

OBJECTIVE: To investigate the percentage of ideal patients who would be eligible for hip-resurfacing surgery at a reference service for hip arthroplasty. METHODS: Out of all the cases of hip arthroplasty operated at Hospital do Servidor Público Estadual de São Paulo (HSPE) between January 2009 and December 2010, we assessed a total of 592 procedures that would fit the criteria for indication for resurfacing arthroplasty, after clinical and radiological evaluation according to the criteria established by the Food and Drug Administration (FDA) and by Seyler et al. RESULTS: Among the total number of hip replacement arthroplasty cases, 5.74% of the patients were eligible. Among the patients who underwent primary arthroplasty, we found that 8.23% presented ideal conditions for this procedure. CONCLUSION: The study demonstrated that this type of surgery still has a limited role among hip surgery methods.

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El objetivo es presentar caso clínico de control de daños, el cual se complementó con angioembolización, lo que ha sido denominado Control de Daños Plus. Paciente masculino de 27 años de edad, quien ingresó a la Unidad de Cirugía de Emergencia del Hospital Universitario de Caracas posterior a arrollamiento, inestable, con un trauma pélvico severo. Es llevado a quirófano donde se le realizó cirugía de control de daños. Por persistencia del sangrado pélvico, se le realizó arteriografía y embolización selectiva de vasos sangrantes. Evolución satisfactoria, decidiéndose su alta médica a los 45 días de postoperatorio y remitido a plan de rehabilitación. La combinación de la cirugía de control de daños y angioembolización es una estrategia factible para el control del sangrado pélvico de pacientes en Fase II, representando una alternativa poco invasiva, que debe ser tomada en cuenta

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Aplicando una metodología de investigación no experimental transeccional descriptiva, se describió al sector que produce y comercializa cosméticos de la ciudad de Bogotá, Colombia, para el segundo semestre de 2004. El modelo empleado contempló tanto el diseño, elaboración y desafío del instrumento de captura de información, como la definición de la población que formó parte del proyecto, cuyo tamaño, después de confirmar la pertenencia al estudio, ameritó continuarlo mediante la técnica del censo poblacional. La encuesta fue diligenciada mediante entrevista al profesional técnico con mayor responsabilidad dentro de la organización o en su defecto por el gerente o su delegado. Además de lograr un acercamiento al sector de cosméticos, el análisis de los resultados obtenidos permitió concluir sobre las características que describen su estado actual, consolidando una base de datos de la población de cosméticos de la ciudad de Bogotá, y la información para posteriores contactos. Se encontró que la población estudiada no ha superado los 50 años desde su fundación, su capital es principalmente nacional, PYMEs, con baja conciencia de agremiación y clientes esencialmente locales. Sólo la mitad de los miembros de la población son productores, con problemas en sus procesos de transformación de materiales

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Este proyecto se hizo con el fin de proveer a la comunidad científica de un micromanipulador de alta calidad, de bajo costo y útil para manipular células con fines de investigación y aplicación biológica. Los procedimientos que se llevaron acabo fueron: - Diseño del prototipo del micromanipulador, de fácil manejo para ser utilizado en técnicas de reproducción asistida.- Estudio de los posibles materiales, su disponibilidad, su durabilidad y su resistencia.- Análisis del costo de los materiales, del diseño, de la mano de obra y su relación costo beneficio.- Construcción del micromanipulador y realización de diferentes pruebas de su utilidad y aplicación en animales, u otros experimentos biológicos no humanos. Se logro obtener una herramienta para técnicas de reproducción asistida al que, además, puedan integrársele posteriormente nuevos dispositivos para las múltiples aplicaciones...

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Entre los años 1991 y 1994 se realizó un estudio prospectivo de biopsias por aspiración obtenidas bajo guía ultrasónica en 72 pacientes con un promedio de edad de 56 años (rango de 12 a 85 años). El tamaño promedio de las lesiones fue de 5 cm (rango de 1 a 14 cm). La naturaleza de las lesiones fue confirmado en todos los casos, por cirugía, imágenes, curso clínico y/o autopsia. La sensibilidad del método fue de 90 porciento y su especificidad de 100 porciento en tanto que el valor predictivo negativo para neoplasia fue de 64 porciento. Sólo se presentaron complicaciones en el 2,7 porciento de los casos. Los resultados alcanzados concuerdan con los de otros autores y confirman que la biopsia por punción bajo visión con ultrasonido y estudio histocitológico del material obtenido es una técnica de bajo costo, segura y de alto rendimiento en el estudio de masas intraabdominales

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