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Purpose. To evaluate the feasibility of use of an 1.5 T magnetic resonance (MR)-linear accelerator MR-linac for imaging in gynaecologic high-dose-rate (HDR) brachytherapy.Method. Commissioning measurements for MR images quality control, geometric distortion, dwell position accuracy, applicator reconstruction and end-to-end test for a tandem-and-ring applicator were performed following the recommendations of American Brachytherapy Society, International Commission on Radiation Units and Measurements and Report of the Brachytherapy Working Group of the Spanish Society of Medical Physics. The values for MR-based IGABT were compared to the corresponding values with computed tomography (CT).Results. Measured distorsions for the MR images were less than 0.50 mm compared to the CT images. The differences between 3D displacements for all dwell positions were 0.66 mm and 0.62 mm for the tandem and ring, respectively. The maximum difference is 0.64 mm for the distances from the applicator tip obtained using the films. The CT and MR dose differences for the right and left 'A' points were 0.9% and -0.7%, respectively. Similar results were observed in terms of dose distribution for CT and Mr The gamma passing rate was 99.3% and 99.5%, respectively.Conclusion. The use of MR images from an MR-linac used in a radiotherapy service for gynaecological brachytherapy was proved to be feasible, safe and precise as the geometrical differences were less than 1 mm, and the dosimetric differences were less than 1% when comparing to the use of CT images for the same purpose.

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BACKGROUND: Eating disorders and food ingestion (EDs) are serious mental illnesses with a higher prevalence in young adults, with difficult diagnoses that cause serious morbidity and mortality problems. There is not much information about the risk of positive screening for EDs, specifically, anorexia nervosa (AN) and bulimia nervosa (BN) and night eating syndrome (NES) in undergraduate medical interns (UMI) and medical residents (MR) in Mexico. AIM: To determine the risk of AN, BN and NES and to determine the risk factors of such conditions such as age, body mass index (BMI) and gender of MR and UMI with AN/BN and NES at four private hospitals in northeastern Mexico. METHODS: A cross-sectional, descriptive, non-randomized survey in MR and UMI in four hospitals in Northeastern Mexico was conducted using an electronic questionnaire that included: informed consent signature, SCOFF questionnaire for AN and BN screening, NES questionnaire. Also, a survey on general sociodemographic data of each participant was included. Chi-square test and a logistic regression model were computed for analyses. RESULTS: The population included a total of 129 MR and UMI. It was observed that 48.8% were positive for AN or BN and 32.6% were positive for the NES. There was no difference between age, sex, BMI, or medical specialty (if they were MR); however, MR from the first year had a higher risk of AN or BN (OR 23.7, 95% CI 1.181-475.266). CONCLUSIONS: There was a higher risk of positive screening for AN or BN and NES in UMI and MR in our population. In the case of MR, those in first year have a higher risk of AN and BN. Timely diagnosis and treatment are mandatory in this population.

Eating disorders and food ingestion such as anorexia (AN) or bulimia (BN) nervosa and night eating syndrome (NES) are a group of mental illnesses that are frequently under diagnosed. Medical residents (MR) and undergraduate medical interns (UMI) are a high-risk population for such disorders due to their young age, stress environments, erratic eating patterns and long working hours. The aim of this study was to determine the risk of AN, BN and NES and to determine the risk factors of such conditions. One hundred twenty-nine UMI and MR were studied and showed that 48.8% were positive for AN or BN and 32.6% were positive for NES. MR in the first year of medical residency had a higher risk. Timely diagnosis and treatment are mandatory in this population.

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The Neuropathy Score Reporting and Data System (NS-RADS) is a newly developed MR imaging-based classification that standardizes reporting and multidisciplinary communication for MR imaging diagnosis and follow-up of peripheral neuropathies. NS-RADS classification has shown to be accurate and reliable across different centers, readers' experience levels, and degrees of peripheral neuropathies, which include nerve injury, entrapment, neoplasm, diffuse neuropathy, post-interventional status, and temporal changes in muscle denervation. This article brings a practical review of NS-RADS classification, representative MR cases, and a step-by-step tutorial on how to approach this staging system. Readers can gain knowledge and apply it in their practice, aiming to standardize the communications between specialties and improve patient management.

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Increased activity in the insula has been consistently reported to be associated with anxiety and anxiety-related disorders. However, little is known on how the insula regulates anxiety. The present study aims at determining the role of the insula on the effects of glucocorticoids in anxiety. A combination of pharmacological manipulations, including blockade of adrenal GC synthesis by metyrapone and intra-insular microinjections of corticosterone, corticosterone-BSA, mineralocorticoid receptor (MR) antagonist spironolactone and glucocorticoid receptor (GR) antagonist mifepristone, were used to assess the short-term (5 min) effects of intra-insular corticosterone in two anxiety-like behaviors in male Sprague-Dawley rats. The elevated plus maze (EPM) and Novelty Suppressed Feeding (hyponeophagia) were utilized. We found that corticosterone in the insula is sufficient to prevent the anxiolytic effects corticosterone synthesis blockade in anxiety, and that intra-insular corticosterone has anxiolytic or anxiogenic effects depending on the amount of corticosterone microinjected and the arousal associated to the test, without affecting the HPA axis. Glucocorticoid anxiolytic effects in the insula are mediated by MRs, while its anxiogenic effects are dependent on a mifepristone-sensitive membrane-bound mechanism. Anxiety appears to be modulated at the insula through a competition between fast MR-dependent anxiolytic and membrane-associated anxiogenic signaling pathways that orchestrate the behavioral response to stress and determines the resulting level of anxiety.

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The challenge of knowing the events surrounding the modern origins of the different specialties of Chilean medicine should be of interest to the specialists of these specialties. Thus, in the case of surgery, fortunately in Chile there are testimonial documents, which reviewed and analyzed can suggest this question, mentioning the one who today is considered the world father of modern surgery, whose important surgical teachings were delivered to Chilean disciples who introduced it in our country. In the context of the War of the Pacific, in the year 1879, a "blood hospital" was built in Santiago, donated by Domingo Matte, a Chilean politician, to receive the many war wounded who were transported from the north. It was Dr. Manuel Barros Borgoño, a young surgeon recently graduated from the Faculty of Medicine in Paris, with a degree revalidated in Chile, who in 1880 took charge of this hospital, and together with his team, began to apply his experience in listerian methods learned in Paris from his teacher Dr. Just Lucas Champonniere. Just Lucas Champonniere, giving beginning to the Chilean antiseptic surgery, managing to reduce the mortality of surgeries to 3%, compared to 80% of other Chilean hospitals that refused to change, and continued with the use of sponge soaked in cerato (lard).

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Takayasu Arteritis (TA) is classified as a large vessel vasculitis, it primarily affects aorta and principal branches. The clinical presentation in pediatric patients is odd and there a few literature about it. The case is about a feminine patient hospitalized after birth with diagnosis of patent ductus arterious (PDA), abnormal widening of the descending aorta, aneurysm of the aortic arch. It is kept under close surveillance for 5 years, with imaging improvement in treatment with methotrexate and immunoglobulin, however she presented relapses on two occasions where the caliber decreased in descending aorta and left iliac artery. We can conclude that Identifying AT findings is important for early diagnosis, medical management, and proper monitoring specifically in pediatric patients where little literature is available.

La arteritis de Takayasu (AT) se clasifica como una vasculitis de grandes vasos desarrollándose sobre todo en aorta y ramas principales. Su presentación en pacientes pediátricos es rara y existe muy poca información en la literatura. Se trata de una paciente femenina hospitalizada al nacimiento, a quien se diagnostica ductus arterioso persistente (DAP), dilatación de aorta descendente y aneurisma de arco aórtico. Se mantiene bajo vigilancia estrecha durante cinco arios, con mejoría imagenológica en tratamiento a base metrotexato e inmunoglobulina, sin embargo, presenta recaídas en dos ocasiones, donde se observa disminución del calibre de aorta descendente y arteria iliaca izquierda. Se puede concluir que el identificar los hallazgos de la AT es importante para realizar un diagnóstico temprano, manejo médico oportuno y vigilancia adecuada, en específico en pacientes pediátricos, de quienes se tiene poca información en la literatura.

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RESUMO Objetivo: Descrever o IMPACTO-MR, um estudo brasileiro de plataforma nacional em unidades de terapia intensiva focado no impacto das infecções por bactérias multirresistentes relacionadas à assistência à saúde. Métodos: Descrevemos a plataforma IMPACTO-MR, seu desenvolvimento, critérios para seleção das unidades de terapia intensiva, caracterização da coleta de dados, objetivos e projetos de pesquisa futuros a serem realizados na plataforma. Resultados: Os dados principais foram coletados por meio do Epimed Monitor System® e consistiram em dados demográficos, dados de comorbidades, estado funcional, escores clínicos, diagnóstico de internação e diagnósticos secundários, dados laboratoriais, clínicos e microbiológicos e suporte de órgãos durante a internação na unidade de terapia intensiva, entre outros. De outubro de 2019 a dezembro de 2020, 33.983 pacientes de 51 unidades de terapia intensiva foram incluídos no banco de dados principal. Conclusão: A plataforma IMPACTO-MR é um banco de dados clínico brasileiro de unidades de terapia intensiva focado na pesquisa do impacto das infecções por bactérias multirresistentes relacionadas à assistência à saúde. Essa plataforma fornece dados para o desenvolvimento e pesquisa de unidades de terapia intensiva individuais e ensaios clínicos observacionais e prospectivos multicêntricos.

ABSTRACT Objective: To describe the IMPACTO-MR, a Brazilian nationwide intensive care unit platform study focused on the impact of health care-associated infections due to multidrug-resistant bacteria. Methods: We described the IMPACTO-MR platform, its development, criteria for intensive care unit selection, characterization of core data collection, objectives, and future research projects to be held within the platform. Results: The core data were collected using the Epimed Monitor System® and consisted of demographic data, comorbidity data, functional status, clinical scores, admission diagnosis and secondary diagnoses, laboratory, clinical, and microbiological data, and organ support during intensive care unit stay, among others. From October 2019 to December 2020, 33,983 patients from 51 intensive care units were included in the core database. Conclusion: The IMPACTO-MR platform is a nationwide Brazilian intensive care unit clinical database focused on researching the impact of health care-associated infections due to multidrug-resistant bacteria. This platform provides data for individual intensive care unit development and research and multicenter observational and prospective trials.

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Positron emission tomography (PET) combined with a magnetic resonance (MR) scanner (PET/MR) with 18F-fluorodeoxyglucose (FDG) tracer is being used in quite a few nuclear medicine centers. The aim of this study is to illustrate two uncommon cases of primary inferior vena cava leiomyosarcoma which were formerly evaluated with anatomical images such as computed tomography and ultrasound. These techniques were inferior in the definition of the tumor and its characteristics. F-18 FDG PET/MR was essential and provided all the necessary information: its origin, local extension, anatomo-metabolic behavior, form of presentation, and distant metastasis in one single diagnostic technique. PET/MR accurately contributed to the diagnosis in a shortened period of time and, therefore, in the prognosis of this disease with greater benefits.

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Few studies have assessed biomarkers for the differentiation of major depressive disorder (MDD) and bipolar disorder (BD). However, some elements of depression such as hormones and receptors of the renin-angiotensin-adrenal system (RAAS), the hypothalamus-pituitary-adrenal (HPA) axis, and history of early-life stress (ELS) could be considered for differential diagnosis. Therefore, this study aimed to assess aldosterone and cortisol levels, MR and GR gene polymorphisms, and ELS as potential biomarkers for differentiating MDD and BD. This study presents a case-control design. Groups comprised samples for genetic, cortisol, and aldosterone analysis: healthy control (HC; n = 113/97/103), MDD (n = 78/69/67) and BD (n = 82/68/65) subjects. Furthermore, all subjects were assessed for diagnostic screening, the severity of depression, and history of ELS by applying MINI-PLUS, GRID-HDRS, and CTQ, respectively. In addition, genotype and allelic frequencies of GR (N363S, R22/23K and BclI) and MR (MI180V and -2G/C) polymorphisms were evaluated via PCR. Our findings demonstrate that basal aldosterone levels may be a biomarker for differentiating BD and MDD. Furthermore, ELS affects the HPA axis in BD, cortisol may be considered a biomarker for distinguishing BD and MDD, but only in the absence of ELS, and, finally, history of ELS and MR-2G/C variant alleles are factors that contribute to the severity of depressive symptoms in MDD and BD.

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Mucosal-associated invariant T (MAIT) cells are restricted by MR1 and are known to protect against bacterial and viral infections. Our understanding of the role of MAIT cells in parasitic infections, such as visceral leishmaniasis (VL) caused by protozoan parasites of Leishmania donovani, is limited. This study showed that in response to L. infantum, human peripheral blood MAIT cells from children with leishmaniasis produced TNF and IFN-γ in an MR1-dependent manner. The overall frequency of MAIT cells was inversely correlated with alanine aminotransferase levels, a specific marker of liver damage strongly associated with severe hepatic involvement in VL. In addition, there was a positive correlation between total protein levels and the frequency of IL-17A+ CD8+ MAIT cells, whereby reduced total protein levels are a marker of liver and kidney damage. Furthermore, the frequencies of IFN-γ+ and IL-10+ MAIT cells were inversely correlated with hemoglobin levels, a marker of severe anemia. In asymptomatic individuals and VL patients after treatment, MAIT cells also produced IL-17A, a cytokine signature associated with resistance to visceral leishmaniasis, suggesting that MAIT cells play important role in protecting against VL. In summary, these results broaden our understanding of MAIT-cell immunity to include protection against parasitic infections, with implications for MAIT-cell-based therapeutics and vaccines. At last, this study paves the way for the investigation of putative MAIT cell antigens that could exist in the context of Leishmania infection.

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This work presents the development of semiactive knee orthosis prototype that focus to absorb the forces and impacts in this joint during the human gait. This prototype consists of three subsystems: the first is a wireless and portable system capable of measuring the ground reaction forces in the stance phase of the gait cycle, by means of an instrumented insole with force sensing resistors strategically placed on the sole of the foot, an electronic device allows processing and transmit this information via Bluetooth to the control system. The second is a semiactive actuator, which has inside a magnetorheological fluid, highlighting its ability to modify its damping force depending on the intensity of the magnetic field that circulates through the MR fluid. It is regulated by a Proportional Derivative (PD) controller system according to the values of plantar pressure measured by the insole. The third component is a mechanical structure manufactured by 3D printing, which adapts to the morphology of the human leg. This exoskeleton is designed to support the forces on the knee controlling the action of the magnetorheological actuator by ground reaction forces. The purpose of this assistance system is to reduce the forces applied to the knee during the gait cycle, providing support and stability to this joint. The obtained experimental results indicate that the device fulfills the function by reducing 12 % of the impact forces on the user's knee.

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PURPOSE: To evaluate multicenter repeatability and reproducibility of T1 and T2 maps generated using MR fingerprinting (MRF) in the International Society for Magnetic Resonance in Medicine/National Institute of Standards and Technology MRI system phantom and in prostatic tissues. METHODS: MRF experiments were performed on 5 different 3 Tesla MRI scanners at 3 different institutions: University Hospitals Cleveland Medical Center (Cleveland, OH), Brigham and Women's Hospital (Boston, MA) in the United States, and Diagnosticos da America (Rio de Janeiro, RJ) in Brazil. Raw MRF data were reconstructed using a Gadgetron-based MRF online reconstruction pipeline to yield quantitative T1 and T2 maps. The repeatability of T1 and T2 values over 6 measurements in the International Society for Magnetic Resonance in Medicine/National Institute of Standards and Technology MRI system phantom was assessed to demonstrate intrascanner variation. The reproducibility between the 4 clinical scanners was assessed to demonstrate interscanner variation. The same-day test-retest normal prostate mean T1 and T2 values from peripheral zone and transitional zone were also compared using the intraclass correlation coefficient and Bland-Altman analysis. RESULTS: The intrascanner variation of values measured using MRF was less than 2% for T1 and 4.7% for T2 for relaxation values, within the range of 307.7 to 2360 ms for T1 and 19.1 to 248.5 ms for T2 . Interscanner measurements showed that the T1 variation was less than 4.9%, and T2 variation was less than 8.1% between multicenter scanners. Both T1 and T2 values in in vivo prostatic tissue demonstrated high test-retest reliability (intraclass correlation coefficient > 0.92) and strong linear correlation (R2  > 0.840). CONCLUSION: Prostate MRF measurements of T1 and T2 are repeatable and reproducible between MRI scanners at different centers on different continents for the above measurement ranges.

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We retrospectively analyzed clinical, NCS/EMG, and NMRI aspects of five COVID-19 intensive care unit inpatients that received mechanical ventilation. After awakening from sedation, they experienced peripheral neuromyopathic symptoms. Teaching Point: Acquired peripheral nerve injury has been described in COVID-19 infection and knowledge of the clinical, nerve conduction studies/electromyography (NCS/EMG) and neurographic magnetic resonance imaging (NMRI) findings are crucial.

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This paper proposes a time-series stochastic socioeconomic model for analyzing the impact of the pandemic on the regulated distribution electricity market. The proposed methodology combines the optimized tariff model (socioeconomic market model) and the random walk concept (risk assessment technique) to ensure robustness/accuracy. The model enables both a past and future analysis of the impact of the pandemic, which is essential to prepare regulatory agencies beforehand and allow enough time for the development of efficient public policies. By applying it to six Brazilian concession areas, results demonstrate that consumers have been/will be heavily affected in general, mainly due to the high electricity tariffs that took place with the pandemic, overcoming the natural trend of the market. In contrast, the model demonstrates that the pandemic did not/will not significantly harm power distribution companies in general, mainly due to the loan granted by the regulator agency, named COVID-account. Socioeconomic welfare losses averaging 500 (MR$/month) are estimated for the equivalent concession area, i.e., the sum of the six analyzed concession areas. Furthermore, this paper proposes a stochastic optimization problem to mitigate the impact of the pandemic on the electricity market over time, considering the interests of consumers, power distribution companies, and the government. Results demonstrate that it is successful as the tariffs provided by the algorithm compensate for the reduction in demand while increasing the socioeconomic welfare of the market.

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Introdução: A doença hepática gordurosa não alcoólica (DHGNA) é uma das causas mais comuns de hepatopatia. Devido ao grande risco de progressão para cronicidade, seu rastreamento se faz necessário. A Elastografia por Ressônancia Magnética (MRE) foi estabelecida em diversos estudos como uma técnica acurada para o diagnóstico de fibrose. Objetivos: Descrever a prevalência de esteatose e de fibrose hepática em pacientes com DHGNA submetidos à MRE; estimar o grau de fibrose, correlacionando com a escala METAVIR, e avaliar a fração de gordura por densidade de prótons (PDFF) e os fatores clínicos associados à esteatose e fibrose. Métodos: Estudo transversal, realizado mediante revisão de imagens de MRE, entre janeiro de 2017 e março de 2019, em um hospital da região sul do Brasil. Resultados: Dos 298 pacientes incluídos, a maioria dos pacientes apresentava esteatose leve (41,6%, n=124) ou ausente (30,9%, n=92), enquanto 15,1% (n=45) apresentava esteatose moderada e 12,4% (n=37), acentuada. A maioria dos pacientes (65,8%, n=181) apresentava rigidez hepática dentro da normalidade, 11,6% (n=32) inflamação crônica, 7,6% (n=21) fibrose estágio 1-2, 3,6% (n=10) fibrose estágio 2-3, 4,7% (n=13) fibrose estágio 3-4 e 6,5% (n=18) fibrose estágio 4 ou cirrose. Discussão: Os resultados encontrados nesta amostra reforçam os fatores de risco para o desenvolvimento de DHGNA previamente avaliados. Uma combinação de estratégias não invasivas, incluindo a MRE, poderá selecionar os pacientes com maior probabilidade de agravos. Conclusão: Nesse estudo, a maioria dos pacientes apresentou a forma leve ou ausência de esteatose e rigidez hepática dentro da normalidade. A MRE tem se mostrado uma técnica altamente acurada, não invasiva para estadiamento de fibrose hepática em pacientes com DHGNA, sem influência significativa da idade, sexo, adiposidade e grau de inflamação hepática.

Introduction: Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of liver disease. Due to the high risk of progression to chronicity, its tracking is necessary. Magnetic Resonance Elastography (MRE) has been established in several studies as an accurate technique for diagnosing fibrosis. Objectives: To describe the prevalence of steatosis and liver fibrosis in NAFLD patients undergoing MRE; estimate the degree of fibrosis, correlating with the METAVIR scale, and assess the proton density fat-fraction (PDFF). Methods: A cross-sectional study, performed by reviewing MRE images, between January 2017 and March 2019, in a hospital in southern Brazil. Results: Of the 298 patients included, most patients had mild (41.6%, n=124) or absent (30.9%, n=92) steatosis, while 15.1% (n=45) had moderate and 12.4% (n=37) marked steatosis. Most patients (65.8%, n=181) had liver stiffness within the normal range, 11.6% (n=32) chronic inflammation, 7.6% (n=21) stage 1-2 fibrosis, 3.6% (n=10) stage 2-3 fibrosis, 4.7% (n=13) stage 3-4 fibrosis, and 6.5% (n=18) stage 4 fibrosis or cirrhosis. Discussion: The results found in this sample reinforce the risk factors for the development of NAFLD previously evaluated. A combination of non-invasive strategies, including MRE, may select the patients with the greatest likelihood of harm. Conclusions: MRE has been shown to be a highly accurate, non-invasive technique for staging liver fibrosis in NAFLD patients, with no significant influence of age, sex, adiposity, and degree of liver inflammation.

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Abstract Introduction: Surgical treatment options are limited for nasopharyngeal cancer for many reasons including epidemiological and histological properties, proximity to important structures, heavy lymphatic drainage, and the difficulty in ensuring a safe surgical margin; therefore primary treatment is generally radiotherapy and chemotherapy. With current radiotherapy technology, oncological success has been increased and the quality of life of patients during the postradiotherapy period is improved. Objective: The role of magnetic resonance imaging and positron emission-computed tomography in the follow-up of recurrent nasopharyngeal cancer patients who were initially treated with radiotherapy was evaluated with respect to histopathological findings. Methods: A total of 110 patients with nasopharyngeal cancer who had received radiotherapy were included in the study. Patients who were suspected to have recurrence according to endoscopic nasopharyngeal examination and magnetic resonance imaging findings were requested to undergo positron emission-computed tomography. Biopsies were taken from 40 patients who had suspicious lesions in positron emission-computed tomography images. These patients' age, gender, presence/absence of contrast enhancement on magnetic resonance imaging, the SuvMax values of nasopharyngeal and neck lesions, T/N phases at initial diagnosis, histopathological recurrence, and history of neck dissection were assessed. Results: Recurrence was observed in 8 patients (20.0%). Among these, 4 (10.0%) had recurrence at the nasopharynx and 4 (10.0%) at the neck. Patients with recurrence were found to be of older age, male gender, advanced T/N phase, contrast enhancement on magnetic resonance imaging, and higher nasopharyngeal and neck SuvMax values in positron emission-computed tomography. However, these differences were not statistically significant. Only the history of neck dissection was significantly more common among those with recurrence (p < 0.001). However, in multivariate analysis, those with a nasopharyngeal SuvMax value higher than 4.58 were found to have 7.667-fold higher risk for recurrence (p = 0.036). Conclusions: Magnetic resonance imaging and positron emission-computed tomography should be evaluated together in the follow-up of nasopharyngeal cancer. Patients with minimal SuvMax 4.58 on positron emission-computed tomography after contrast enhancement in the T2 sequence on magnetic resonance imaging may considered appropriate for biopsy. Biopsies in patients with a SuvMax value lower than 4.58 can be avoided. Thus, patients avoid surgical stress and unnecessary costs.

Resumo Introdução: As opções de tratamento cirúrgico são limitadas para o carcinoma nasofaríngeo por várias razões, inclusive aspectos epidemiológicos e histológicos, proximidade de estruturas importantes, drenagem linfática carregada e dificuldade de garantir uma margem cirúrgica segura; portanto, o tratamento primário é geralmente radioterapia e quimioterapia. Com a tecnologia atual de radioterapia, o sucesso oncológico aumentou e a qualidade de vida dos pacientes durante o período pós-radioterapia é garantida. Objetivo: O papel da ressonância magnética e da tomografia computadorizada por emissão de pósitrons no seguimento de pacientes com carcinoma nasofaríngeo recorrente, inicialmente tratados com radioterapia, foi avaliado em relação aos achados histopatológicos. Método: Foram incluídos no estudo 110 pacientes com carcinoma nasofaríngeo que receberam radioterapia. Pacientes com suspeita de recorrência de acordo com o exame endoscópico nasofaríngeo e com achados de ressonância magnética foram solicitados a fazer tomografia computadorizada por emissão de pósitrons. Foram feitas biópsias de 40 pacientes com lesões suspeitas nas imagens de tomografia computadorizada por emissão de pósitrons. Os pacientes foram avaliados segundo idade, sexo, presença/ausência de realce por contraste na ressonância magnética, valores SUVmax de lesões nasofaríngeas e cervicais, estágios T/N no diagnóstico inicial, recorrência histopatológica e histórico de esvaziamento cervical. Resultados: A recorrência foi observada em 8 pacientes (20,0%). Entre esses, 4 (10,0%) apresentaram recorrência na nasofaringe e 4 (10,0%) no pescoço. Pacientes com recorrência eram do sexo masculino, apresentavam idade mais avançada, estágio avançado T/N, realce por contraste na ressonância magnética e maiores valores de SuvMax nasofaríngeo e cervical na tomografia computadorizada por emissão de pósitrons. Entretanto, essas diferenças não foram estatisticamente significantes. Apenas o histórico de esvaziamento cervical foi significantemente mais comum entre aqueles com recorrência (p < 0,001). No entanto, na análise multivariada, aqueles com um valor de SUVmax nasofaríngeo superior a 4,58 apresentaram um risco 7,667 vezes maior de recorrência (p = 0,036). Conclusão A ressonância magnética e a tomografia computadorizada por emissão de pósitrons devem ser avaliadas em conjunto no seguimento da doença. Pacientes com valor de SUVmax mínimo de 4,58 na tomografia computadorizada por emissão de pósitrons após realce com contraste na sequência T2 na ressonância magnética podem ser considerados mais adequados para biópsia. Biópsias em pacientes com um valor de SUVmax menor do que 4,58 podem ser evitadas. Dessa forma, podemos evitar o estresse cirúrgico para o paciente e custos desnecessários.

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Ray-finned fishes of the superorder Ostariophysi are primarily freshwater (FW), and normally stenohaline. Differently, fishes of the superorder Acanthopterygii are essentially marine, and frequently euryhaline, with some secondary FW. Na+/K+-ATPase-immunoreactive ionocytes were localized in the branchial epithelia of 4 species of Ostariophysi and 3 of Acanthopterygii. The Ostariophysi grass carp (Ctenopharyngodon idella, Cypriniformes), twospot Astyanax (Astyanax bimaculatus) and piracanjuba (Brycon orbignyanus), Characiformes, and the jundiá (Rhamdia quelen, Siluriformes), all from FW, displayed ionocytes in the filament plus secondary lamellae (F + SL). In their turn, all the three species of Acanthopterygii showed immunoreactive ionocytes in the filaments only (F). They were the Nile tilapia (Oreochromis niloticus, Cichliformes) in FW, the dog snapper (Lutjanus jocu, Perciformes) in seawater (SW), and the green puffer (Sphoeroides greeleyi, Tetraodontiformes) in SW. Ionocytes normally extend their distribution to the secondary lamellae (F + SL) in Ostariophysi. In Acanthopterygii, we find more plasticity: ionocytes are more frequently restricted to the filament in SW, but also spread to SL in FW. It may be that the occurrence of ionocytes in SL is the ancestral condition, but some euryhaline acanthopterygians rely on the space of the SL for placement of additional ionocytes when in FW absorbing salt. Our study contributed to the identification of the pattern of ionocyte distribution in gills of Ostariophysi in respect to that of Acanthopterygii.

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Introduction Squamous cell Carcinoma of the Head and Neck (HNSCC) is the most common tumor entity of malignant processes in the head and neck area. Due to the metastasizing behavior of these tumors, the staging is indispensable for the treatment planning and requires imaging techniques, which are sensitive, specific, and as far as possible cost-effective, to benefit ultimately the patient and to ensure optimal care. Objectives The aim of the present study is to compare the clinical examination including palpation, ultrasound and computed tomography (CT)/magnetic resonance imaging (MRI) for the diagnosis of neck metastases to make the correct indication for a neck dissection. Methods Data from 286 patients with HNSCC were analyzed for neck metastases to determine which diagnostic tool is the best to answer the question if a neck dissection is necessary or not. Each study method was examined retrospectively by comparing sensitivity, specificity, the positive/negative predictive value, the positive likelihood ratio and the diagnostic accuracy. Results The ultrasound showed a sensitivity of 91.52%, a specificity of 61.67%, a positive/negative predictive value of 76.65%/84.09%, a positive likelihood ratio of 2.39 and a diagnostic accuracy of 78.95%. The clinical examination showed a sensitivity of 75.76%, a specificity of 66.12%, a positive/negative predictive value of 75.30%/66.67%, a positive likelihood ratio of 2.24 and a diagnostic accuracy of 71.68%. The CT/MRI showed a sensitivity of 78.66%, a specificity of 62.50%, a positive/negative predictive value of 74.14%/68.18%, a positive likelihood ratio of 2.10 and a diagnostic accuracy of 71.83%. Radiographically, ultrasound, as well as the clinical examination, could be judged to be free from radiation load and side effects from the contrast medium. The high dependence on the investigator when using ultrasound made reproducibility of the results difficult. Conclusions It could be shown that ultrasound was the diagnostic tool with the highest sensitivity, positive/negative predictive value, positive likelihood ratio and diagnostic accuracy by detecting and interpreting metastases in the head and neck region correctly. Whether a neck dissection should be performed depends to a large extent on the ultrasound findings.

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Hemocyanins are used as immunomodulators in clinical applications because they induce a strong Th1-biased cell-mediated immunity, which has beneficial effects. They are multiligand glycosylated molecules with abundant and complex mannose-rich structures. It remains unclear whether these structures influence hemocyanin-induced immunostimulatory processes in human APCs. We have previously shown that hemocyanin glycans from Concholepas concholepas (CCH), Fissurella latimarginata (FLH), and Megathura crenulata (KLH), participate in their immune recognition and immunogenicity in mice, interacting with murine C-type lectin receptors (CLRs). Here, we studied the interactions of these hemocyanins with two major mannose-binding CLRs on monocyte-derived human DCs: MR (mannose receptor) and DC-SIGN (DC-specific ICAM-3-grabbing nonintegrin). Diverse analyses showed that hemocyanins are internalized by a mannose-sensitive mechanism. This process was calcium dependent. Moreover, hemocyanins colocalized with MR and DC-SIGN, and were partly internalized through clathrin-mediated endocytosis. The hemocyanin-mediated proinflammatory cytokine response was impaired when using deglycosylated FLH and KLH compared to CCH. We further showed that hemocyanins bind to human MR and DC-SIGN in a carbohydrate-dependent manner with affinity constants in the physiological concentration range. Overall, we showed that these three clinically valuable hemocyanins interact with human mannose-sensitive CLRs, initiating an immune response and promoting a Th1 cell-driving potential.

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