Deep Learning-Based Medical Images Segmentation of Musculoskeletal Anatomical Structures: A Survey of Bottlenecks and Strategies

By leveraging the recent development of artificial intelligence algorithms, several medical sectors have benefited from using automatic segmentation tools from bioimaging to segment anatomical structures. Segmentation of the musculoskeletal system is key for studying alterations in anatomical tissue and supporting medical interventions. The clinical use of such tools requires an understanding of the proper method for interpreting data and evaluating their performance. The current systematic review aims to present the common bottlenecks for musculoskeletal structures analysis (e.g., small sample size, data inhomogeneity) and the related strategies utilized by different authors. A search was performed using the PUBMED database with the following keywords: deep learning, musculoskeletal system, segmentation. A total of 140 articles published up until February 2022 were obtained and analyzed according to the PRISMA framework in terms of anatomical structures, bioimaging techniques, pre/post-processing operations, training/validation/testing subset creation, network architecture, loss functions, performance indicators and so on. Several common trends emerged from this survey; however, the different methods need to be compared and discussed based on each specific case study (anatomical region, medical imaging acquisition setting, study population, etc.). These findings can be used to guide clinicians (as end users) to better understand the potential benefits and limitations of these tools.

Efeito da suplementação com colina protegida sobre parâmetros bioquímicos, produção e reprodução de vacas leiteiras no periparto

RESUMO Avaliou-se o efeito da suplementação com colina protegida sobre o perfil energético, as enzimas hepáticas e a reprodução de vacas leiteiras no periparto. Quinze vacas leiteiras foram divididas em dois grupos experimentais: oito receberam 80 gramas de colina protegida por 21 dias no pré-parto e por 40 dias no pós-parto e sete foram consideradas controle. Amostras de sangue foram coletadas nos dias 10, 20, 30 e 60 pós-parto para avaliação dos perfis energético e hepático. Aos 60 dias pós-parto, realizou-se exame ginecológico dos animais para avaliação da saúde reprodutiva. A suplementação com colina protegida não alterou os níveis de beta-hidroxibutirato (BHBA), ácidos graxos não esterificados (AGNE), frutosamina, fator de crescimento semelhante a glicose I (IGF-I), status oxidante total (TOS), aspartato aminotransferase (AST) e gamaglutamiltransferase (GGT) no pós-parto. Não houve diferença também quanto à produção de leite. Aos 60 dias pós-parto, vacas suplementadas com colina protegida apresentaram menor número de casos de endometrite que vacas do grupo controle. A suplementação de colina protegida não alterou o perfil bioquímico e a produção de leite, mas reduziu o número de casos de endometrite no pós-parto de vacas leiteiras.

Farelo de tungue in natura ou detoxificado na alimentação de carpa húngara (Cyprinus carpio)

Este estudo avaliou a substituição parcial de farinhas de origem animal pelo farelo de tungue como fonte proteica no arraçoamento de carpa húngara. Os tratamentos compreenderam a inclusão de farelo de tungue in naturaou detoxificado (obtido após aplicação de tratamento químico ao farelo), e o tratamento referência consistiu de base proteica composta por farinha de carne e ossos suína e farinha de peixe. O período de alimentação foi de 63 dias. No decorrer de 30 dias experimentais não foi observada diferença em indicadores de crescimento entre os animais que consumiram as rações controle e com farelo de tungue tratado quimicamente, porém o consumo da ração com farelo de tungue in natura provocou redução no desempenho até o final do período experimental. Após 63 dias de arraçoamento, alguns indicadores de crescimento mostraram-se inferiores também para o tratamento que continha farelo de tungue tratado em relação ao controle. A análise bioquímica no plasma e no fígado revelou aumento de triglicerídeos, glicogênio, glicose e a utilização de outras fontes, possivelmente aminoácidos, como precursores energéticos na produção de energia quando os animais consumiram a dieta com farelo de tungue in natura em relação às demais, o que refletiu na menor concentração de proteína e na maior deposição de gordura na carcaça. Em relação à atividade de enzimas digestivas, tripsina apresentou atividade aumentada no tratamento com farelo de tungue in natura e protease ácida, quimotripsina, amilase e lipase não foram alteradas em nenhum dos tratamentos avaliados.

Exposure to sublethal concentrations of Zn(II) and Cu(II) changes biochemical parameters in Leporinus obtusidens

The aim of the present study was to assess the effect of the exposure of Leporinus obtusidens (Piava) to zinc and copper on catalase activity in the liver, delta-aminolevulinate dehidratase (delta-ALA-D) activity in liver, muscle, brain and kidney, and thiobarbituric reactive species (TBARS) in brain, muscle and liver. In addition, hematological parameters were measured in blood. The fish were exposed to 10% and 20% of the derived LC(50) values, 2.3 and 4.6 mg Zn l(-1) and 0.02 and 0.04 mg Cu l(-1), and sampled on days 30 and 45. Exposure to Zn(II) and Cu(II) decreased hematological parameters and also delta-ALA-D activity mainly in liver and kidney at all concentrations tested. Liver catalase activity increased after zinc or copper exposure at all concentrations and exposure times tested. Thiobarbituric reactive substances (TBARS) increased in the brain and liver of the fish exposed to zinc(II) for 45 days at both metal concentrations. In muscle, zinc(II) increased TBARS production at both exposure times and concentrations tested. Copper(II) exposure reduced the TBARS levels in liver at both concentrations and times tested. In brain, there was a decrease in TBARS levels only after 45 days of exposure. In muscle, this decrease was observed after 30 days of exposure at both concentrations. Although zinc and copper are required as microelements in the cells, our results showed that the sublethal concentrations of these metals can change biochemical parameters which may alter normal cellular function. These results pointed out the differential sensitivity of fish tissues to essential, but also toxic and environmentally relevant metals. The alterations of distinct biochemical parameters in fish tissues certainly contribute to the toxicity of Zn and Cu, and are of importance for an area that has been growing and has still been poorly explored in the literature.

Colorimetric determination of formaldehyde in air using a hanging drop of chromotropic acid

A simple and sensitive method to determine parts per billion (ppb) of atmospheric formaldehyde in situ, using chromotropic acid, is described. A colorimetric sensor, coupled to a droplet of 15.5 microL chromotropic acid, was constructed and used to sample and quantify formaldehyde. The sensor was set up with two optical fibers, a light emitting diode (LED) and two photodiodes. The reference and transmitted light were measured by a photodetection arrangement that converts the signals into units of absorbance. Air was sampled around the chromotropic acid droplet. A purple product was formed and measured after the sampling terminated (typically 7 min). The response is proportional to the sampling period, analyte concentration and sample flow rate. The detection limit is approximately 2 ppb and can be improved by using longer sampling times and/or a sampling flow rate higher than that used in this work, 200 mL min-1. The present technique affords a simple, inexpensive near real-time measurement with very little reagent consumption. The method is selective and highly sensitive. This sensor could be used either for outdoor or indoor atmospheres.