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1.
Poult Sci ; 102(8): 102805, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37302332

RESUMO

Arginine is the main amino acid that constitutes the sperm protamine of roosters, named galline, which complexes with sperm DNA, allowing high compaction of its chromatin. Arginine supplementation has positive effects on semen quality in aged roosters, but this supplementation is not known to limit the progressive worsening of sperm chromatin compaction. This work aimed to verify whether L-arginine supplementation in the feed improve or maintain sperm chromatin quality since aging in roosters is usually accompanied by worsening chromatin quality. Four groups of 52-wk-old Ross AP95 lineage roosters were used, of which 6 semen samples per group were evaluated, totaling 24 samples. Another 24 samples, 6 per group, were evaluated after 6 wk of supplementation when one group was not supplemented (control) and the other 3 were supplemented with 1.15 kg (treatment 1), 2.17 kg (treatment 2), and 3.18 kg (treatment 3) of L-arginine/ton of feed. Computer image analysis of semen smears stained with toluidine blue pH 4.0 was used for sperm chromatin evaluation. Sperm chromatin was evaluated for compaction heterogeneity and compaction intensity by percentage decompaction relative to standard heads and by integrated optical density (IOD), which was used for the first time to identify sperm chromatin changes. Sperm head morphology was also evaluated by means of area and length. The IOD proved to be more efficient in identifying changes in rooster sperm chromatin compaction than the percentual decompaction. In general, chromatin compaction was positively influenced by the supplementation with L-arginine, being better in the supplementation with the highest levels tested. This was corroborated by the smaller average of the variables referring to the size of the spermatozoa heads of the animals that received feed with a higher content of L-arginine, since better compacted heads naturally tend to be smaller. Finally, arginine supplementation was able to limit or even improve sperm chromatin decompaction during the experimental period.


Assuntos
Análise do Sêmen , Sêmen , Masculino , Animais , Análise do Sêmen/veterinária , Galinhas , Dieta , Cromatina , Espermatozoides , Suplementos Nutricionais/análise , Arginina/farmacologia , Arginina/análise , Envelhecimento , Motilidade dos Espermatozoides
2.
Appl Soft Comput ; 134: 110014, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36687763

RESUMO

Coronavirus Disease-2019 (COVID-19) causes Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS-CoV-2) and has opened several challenges for research concerning diagnosis and treatment. Chest X-rays and computed tomography (CT) scans are effective and fast alternatives to detect and assess the damage that COVID causes to the lungs at different stages of the disease. Although the CT scan is an accurate exam, the chest X-ray is still helpful due to the cheaper, faster, lower radiation exposure, and is available in low-incoming countries. Computer-aided diagnostic systems based on Artificial Intelligence (AI) and computer vision are an alternative to extract features from X-ray images, providing an accurate COVID-19 diagnosis. However, specialized and expensive computational resources come across as challenging. Also, it needs to be better understood how low-cost devices and smartphones can hold AI models to predict diseases timely. Even using deep learning to support image-based medical diagnosis, challenges still need to be addressed once the known techniques use centralized intelligence on high-performance servers, making it difficult to embed these models in low-cost devices. This paper sheds light on these questions by proposing the Artificial Intelligence as a Service Architecture (AIaaS), a hybrid AI support operation, both centralized and distributed, with the purpose of enabling the embedding of already-trained models on low-cost devices or smartphones. We demonstrated the suitability of our architecture through a case study of COVID-19 diagnosis using a low-cost device. Among the main findings of this paper, we point out the performance evaluation of low-cost devices to handle COVID-19 predicting tasks timely and accurately and the quantitative performance evaluation of CNN models embodiment on low-cost devices.

3.
J Digit Imaging ; 36(3): 1158-1179, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36604364

RESUMO

Using computer vision through artificial intelligence (AI) is one of the main technological advances in dentistry. However, the existing literature on the practical application of AI for detecting cephalometric landmarks of orthodontic interest in digital images is heterogeneous, and there is no consensus regarding accuracy and precision. Thus, this review evaluated the use of artificial intelligence for detecting cephalometric landmarks in digital imaging examinations and compared it to manual annotation of landmarks. An electronic search was performed in nine databases to find studies that analyzed the detection of cephalometric landmarks in digital imaging examinations with AI and manual landmarking. Two reviewers selected the studies, extracted the data, and assessed the risk of bias using QUADAS-2. Random-effects meta-analyses determined the agreement and precision of AI compared to manual detection at a 95% confidence interval. The electronic search located 7410 studies, of which 40 were included. Only three studies presented a low risk of bias for all domains evaluated. The meta-analysis showed AI agreement rates of 79% (95% CI: 76-82%, I2 = 99%) and 90% (95% CI: 87-92%, I2 = 99%) for the thresholds of 2 and 3 mm, respectively, with a mean divergence of 2.05 (95% CI: 1.41-2.69, I2 = 10%) compared to manual landmarking. The menton cephalometric landmark showed the lowest divergence between both methods (SMD, 1.17; 95% CI, 0.82; 1.53; I2 = 0%). Based on very low certainty of evidence, the application of AI was promising for automatically detecting cephalometric landmarks, but further studies should focus on testing its strength and validity in different samples.


Assuntos
Algoritmos , Inteligência Artificial , Humanos , Reprodutibilidade dos Testes , Cefalometria/métodos , Processamento Eletrônico de Dados
4.
J Digit Imaging ; 35(3): 623-637, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35199257

RESUMO

Acute lymphoblastic leukemia (ALL) is the most common childhood cancer worldwide, and it is characterized by the production of immature malignant cells in the bone marrow. Computer vision techniques provide automated analysis that can help specialists diagnose this disease. Microscopy image analysis is the most economical method for the initial screening of patients with ALL, but this task is subjective and time-consuming. In this study, we propose a hybrid model using a genetic algorithm (GA) and a residual convolutional neural network (CNN), ResNet-50V2, to predict ALL using microscopy images available in ALL-IDB dataset. However, accurate prediction requires suitable hyperparameters setup, and tuning these values manually still poses challenges. Hence, this paper uses GA to find the best hyperparameters that lead to the highest accuracy rate in the models. Also, we compare the performance of GA hyperparameter optimization with Random Search and Bayesian optimization methods. The results show that GA optimization improves the accuracy of the classifier, obtaining 98.46% in terms of accuracy. Additionally, our approach sheds new perspectives on identifying leukemia based on computer vision strategies, which could be an alternative for applications in a real-world scenario.


Assuntos
Redes Neurais de Computação , Leucemia-Linfoma Linfoblástico de Células Precursoras , Teorema de Bayes , Criança , Progressão da Doença , Humanos , Processamento de Imagem Assistida por Computador/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico
5.
J Digit Imaging ; 34(3): 678-690, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33948761

RESUMO

The literature provides many works that focused on cell nuclei segmentation in histological images. However, automatic segmentation of bone canals is still a less explored field. In this sense, this paper presents a method for automatic segmentation approach to assist specialists in the analysis of the bone vascular network. We evaluated the method on an image set through sensitivity, specificity and accuracy metrics and the Dice coefficient. We compared the results with other automatic segmentation methods (neighborhood valley emphasis (NVE), valley emphasis (VE) and Otsu). Results show that our approach is proved to be more efficient than comparable methods and a feasible alternative to analyze the bone vascular network.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador
6.
Med. oral patol. oral cir. bucal (Internet) ; 26(3): e368-e378, May. 2021. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-224562

RESUMO

Background: This study aimed to search for scientific evidence concerning the accuracy of computer-assistedanalysis for diagnosing odontogenic cysts.Material and Methods: A systematic review was conducted according to the PRISMA statements and consideringeleven databases, including the grey literature. Protocol was registered in PROSPERO (CRD 42020189349). ThePECO strategy was used to define the eligibility criteria and only studies involving diagnostic accuracy were in-cluded. Their risk of bias was investigated using the Joanna Briggs Institute Critical Appraisal tool.Results: Out of 437 identified citations, five papers, published between 2006 and 2019, fulfilled the criteria andwere included in this systematic review. A total of 5,264 images from 508 lesions, classified as radicular cyst,odontogenic keratocyst, lateral periodontal cyst, glandular odontogenic cyst, or dentigerous cyst, were analyzed.All selected articles scored low risk of bias. In three studies, the best performances were achieved when the twosubtypes of odontogenic keratocysts (solitary or syndromic) were pooled together, the case-wise analysis showinga success rate of 100% for odontogenic keratocysts and radicular cysts, in one of them. In two studies, the den-tigerous cyst was associated with the majority of misclassifications, and its omission from the dataset improvedsignificantly the classification rates. Conclusions: The overall evaluation showed all studies presented high accuracy rates of computer-aided systems inclassifying odontogenic cysts in digital images of histological tissue sections. However, due to the heterogeneity ofthe studies, a meta-analysis evaluating the outcomes of interest was not performed and a pragmatic recommendationabout their use is not possible.(AU)


Assuntos
Humanos , Masculino , Feminino , Cistos Odontogênicos/diagnóstico por imagem , Cisto Radicular , Mandíbula/anormalidades , Processamento de Imagem Assistida por Computador , Saúde Bucal , Patologia Bucal , Cirurgia Bucal , Medicina Bucal
7.
Biosci. j. (Online) ; 37: e37028, Jan.-Dec. 2021. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1358719

RESUMO

This paper proposes to classify the sperm chromatin compaction alterations in bulls, according to the affected area location and its objective is evaluating the correlation of the intensity, the heterogeneity and these kinds of chromatin decompaction with the rates of cleavage and the formation of blastocysts of in vitro production of embryos (IVPE). It was used several subfertile animals sperm samples, which were evaluated using the toluidine blue staining and computer image analysis, making possible the categorization of the chromatin decompaction according to their location. The percentages of chromatin decompaction and heterogeneity were also evaluated. IVPEs were done and the rates of cleavage and of blastocysts were correlated with the chromatin characteristics. It made possible the classification of the chromatin decompaction according to the head affected part in at least four types: base decompaction, basal half decompaction, central axis decompaction, total decompaction. Based on the correlation, it can be implicated that each type of classification has different influences on the bull fertility. It made possible understanding that sperms amount with 5% or more of chromatin decompaction intensity interferes in the bull fertility and this condition can be featured as an uncompensable defect, while the heterogeneity of chromatin is not an important factor in the IVPE results.


Assuntos
Sêmen/diagnóstico por imagem , Espermatozoides , Bovinos , Fertilização In Vitro , Análise do Sêmen
8.
Chemosphere ; 206: 632-642, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29778941

RESUMO

Melipona scutellaris Latreille, 1811 (Hymenoptera, Apidae) is a pollinator of various native and cultivated plants. Because of the expansion of agriculture and the need to ensure pest control, the use of insecticides such as fipronil (FP) has increased. This study aimed to evaluate the effects of sublethal doses of FP insecticide on M. scutellaris at different time intervals (6, 12, and 24 h) after exposure, via individually analyzed behavioral biomarkers (locomotor activity, behavioral change) as well as the effect of FP on different brain structures of bees (mushroom bodies, antennal cells, and optic cells), using sub-individual cell biomarkers (heterochromatin dispersion, total nuclear and heterochromatic volume). Forager bees were collected when they were returning to the nest and were exposed to three different concentrations of FP (0.40, 0.040, and 0.0040 ng a.i/bee) by topical application. The results revealed a reduction in the mean velocity, lethargy, motor difficulty, paralysis, and hyperexcitation in all groups of bees treated with FP. A modification of the heterochromatic dispersion pattern and changes in the total volume of the nucleus and heterochromatin were also observed in the mushroom bodies (6, 12, and 24 h of exposure) and antennal lobes (6 and 12 h) of bees exposed to 0.0040 ng a.i/bee (LD50/100). FP is toxic to M. scutellaris and impairs the essential functions required for the foraging activity.


Assuntos
Ecotoxicologia/métodos , Inseticidas/efeitos adversos , Animais , Abelhas , Brasil
9.
Reprod Biol ; 18(2): 177-181, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29705068

RESUMO

Alterations in sperm chromatin have been related with subfertility in several mammals. In this study, chromatin alteration types (Base, Basal half, Central axis, Dispersed, and Whole) were assessed by toluidine blue (TB) staining, 6-diamidino-2-fenilindole (DAPI) and anti-protamine 1 antibody (anti-PR1) labeling in sperm samples of fertile and subfertile bulls. Semen samples were obtained from bulls kept in Artificial Insemination Center (fertile bulls) or from bulls subjected to scrotal insulation (subfertile bulls). The percentage of chromatin alterations identified by TB was similar (P > 0.05) in semen samples of fertile and subfertile bulls. In contrast, a greater (P < 0.01) chromatin decondensation and heterogeneity were recorded in semen samples of subfertile bulls. In DAPI and anti-PR1 methods, the subfertile bulls samples had a higher (P < 0.05) percentage of alteration in the base as well as overall chromatin alterations (P < 0.05). Moreover, the chromatin alterations recorded with TB, DAPI, and anti-PR1 were compared in semen samples of fertile and subfertile bulls. In fertile bulls, the overall chromatin alterations were similar (P > 0.05) among the methods In contrast, semen samples of subfertile bulls had a higher (P < 0.05) percentage of overall chromatin alterations when labeled with DAPI. In conclusion, our findings shown that all dye tested had specific sperm stainability and can be feasible to monitor subfertility condition in bulls. Also, different chromatin alteration types in sperm samples of fertile and suberftile bulls were recorded.


Assuntos
Cromatina/metabolismo , Fertilidade/fisiologia , Infertilidade Masculina/veterinária , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo , Animais , Bovinos , Infertilidade Masculina/metabolismo , Inseminação Artificial/veterinária , Masculino
10.
J. health inform ; 8(supl.I): 643-652, 2016. ilus, tab
Artigo em Português | LILACS | ID: biblio-906566

RESUMO

Softwares de bioimage são utilizados para a análise de imagens microscópicas e auxiliam os usuários em suas tomadas de decisões, a usabilidade pode limitar o seu uso. OBJETIVOS: Desenvolver um software de bioimage que pode ser acessado em um navegador web. Auxiliar patologistas e outros usuários na tomada de decisão, minimizando a subjetividade de suas avaliações. MÉTODOS: Foram realizados estudos nos softwares de bioimage open sources, o qual foram identificadas as características positivas e negativas, permitindo a escolha das tecnologias apropriadas para desenvolver o ambiente. RESULTADOS: O trabalho proveu um software de bioimage para análise citomorfométrica usando imagens tridimensionais que pode ser acessado por meio de um navegador web. CONCLUSÃO: O ambiente proposto é capaz de subsidiar os usuários com informações sobre as estruturas das células para tomada de decisão, fornecendo dados quantitativos e permitindo a exploração por meio de uma cena tridimensional.


Bioimage softwares are used for the analysis of microscopic images and assist users in their decision making,usability can limit its use. PURPOSES: Develop a bioimage software that can be accessed through a web browser. Assist pathologists and other users in decision making, minimizing the subjectivity of its evaluations. METHODS: Studies were carried out in the bioimage open sources softwares, which have been identified the positive and negative characteristics, allowing the choice of the appropriate technologies to developing the environment. RESULTS: The work provided abioimage software for histomorphometric analysis using three-dimensional images that can be accessed through a webbrowser. CONCLUSION: The proposed environment can subsidize the users with information on the structures of cells to decision making, providing quantitative data and allowing the exploration of a three-dimensional scene.


Assuntos
Humanos , Patologia , Software , Biologia Computacional , Imageamento Tridimensional , Congressos como Assunto , Citometria por Imagem
11.
Arch. endocrinol. metab. (Online) ; 59(6): 507-514, Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-767923

RESUMO

Objective The aim of this study was to evaluate the effects of zoledronic acid (ZA) on the cortical bone channels network (CBCN) and osteocyte organization in relation to the bone channels. Materials and methods Eighteen male Wistar rats were divided into control (CG) and test groups (TG). Twelve animals from TG received 3 ZA doses (7.5 µg/kg), and 6 animals from CG did not receive any medication. TG animals were euthanized at 14 (n = 6) and 75 (n = 6) dadys after drug injection. CBCN was analyzed in mandibles and tibias using computational routines. The osteocyte organization was qualitatively evaluated in tibias using a three-dimensional reconstruction of images from serial histological sections. Results Significant differences in CBCN of tibia were found between the treated and untreated rats, with a wider range of sizes and shapes of the channels after the use of ZA (channels area p = 0.0063, channels area SD p = 0.0276) and less bone matrix (bone volume p = 0.0388). The alterations in the channels’ morphology were more evident at 75 days after the drug injection (channels perimeter p = 0.0286). No differences were found in mandibles CBCN. The osteocyte distribution revealed more variable patterns of cell distribution in ZA groups, with non-homogeneous distribution of cells in relation to the bone channels. Conclusion Zoledronic acid induces structural changes in CBCN and modifies the osteocyte arrangement in cortical bone in the tibia; also, the variability in the morphology of bone channels became more evident after a certain time of the use of the drug.


Assuntos
Animais , Masculino , Conservadores da Densidade Óssea/farmacologia , Difosfonatos/farmacologia , Ósteon/efeitos dos fármacos , Imidazóis/farmacologia , Osteócitos/efeitos dos fármacos , Ósteon/anatomia & histologia , Imageamento Tridimensional , Mandíbula/anatomia & histologia , Mandíbula/efeitos dos fármacos , Ratos Wistar , Estatísticas não Paramétricas , Tíbia/anatomia & histologia , Tíbia/efeitos dos fármacos
12.
Arch Endocrinol Metab ; 59(6): 507-14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26331228

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effects of zoledronic acid (ZA) on the cortical bone channels network (CBCN) and osteocyte organization in relation to the bone channels. MATERIALS AND METHODS: Eighteen male Wistar rats were divided into control (CG) and test groups (TG). Twelve animals from TG received 3 ZA doses (7.5 µg/kg), and 6 animals from CG did not receive any medication. TG animals were euthanized at 14 (n = 6) and 75 (n = 6) dadys after drug injection. CBCN was analyzed in mandibles and tibias using computational routines. The osteocyte organization was qualitatively evaluated in tibias using a three-dimensional reconstruction of images from serial histological sections. RESULTS: Significant differences in CBCN of tibia were found between the treated and untreated rats, with a wider range of sizes and shapes of the channels after the use of ZA (channels area p = 0.0063, channels area SD p = 0.0276) and less bone matrix (bone volume p = 0.0388). The alterations in the channels' morphology were more evident at 75 days after the drug injection (channels perimeter p = 0.0286). No differences were found in mandibles CBCN. The osteocyte distribution revealed more variable patterns of cell distribution in ZA groups, with non-homogeneous distribution of cells in relation to the bone channels. CONCLUSION: Zoledronic acid induces structural changes in CBCN and modifies the osteocyte arrangement in cortical bone in the tibia; also, the variability in the morphology of bone channels became more evident after a certain time of the use of the drug.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Difosfonatos/farmacologia , Ósteon/efeitos dos fármacos , Imidazóis/farmacologia , Osteócitos/efeitos dos fármacos , Animais , Ósteon/anatomia & histologia , Imageamento Tridimensional , Masculino , Mandíbula/anatomia & histologia , Mandíbula/efeitos dos fármacos , Ratos Wistar , Estatísticas não Paramétricas , Tíbia/anatomia & histologia , Tíbia/efeitos dos fármacos , Ácido Zoledrônico
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