Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
2.
Sci Rep ; 13(1): 19178, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932315

RESUMO

Immunocytochemical staining of microorganisms and cells has long been a popular method for examining their specific subcellular structures in greater detail. Recently, generative networks have emerged as an alternative to traditional immunostaining techniques. These networks infer fluorescence signatures from various imaging modalities and then virtually apply staining to the images in a digital environment. In numerous studies, virtual staining models have been trained on histopathology slides or intricate subcellular structures to enhance their accuracy and applicability. Despite the advancements in virtual staining technology, utilizing this method for quantitative analysis of microscopic images still poses a significant challenge. To address this issue, we propose a straightforward and automated approach for pixel-wise image-to-image translation. Our primary objective in this research is to leverage advanced virtual staining techniques to accurately measure the DNA fragmentation index in unstained sperm images. This not only offers a non-invasive approach to gauging sperm quality, but also paves the way for streamlined and efficient analyses without the constraints and potential biases introduced by traditional staining processes. This novel approach takes into account the limitations of conventional techniques and incorporates improvements to bolster the reliability of the virtual staining process. To further refine the results, we discuss various denoising techniques that can be employed to reduce the impact of background noise on the digital images. Additionally, we present a pixel-wise image matching algorithm designed to minimize the error caused by background noise and to prevent the introduction of bias into the analysis. By combining these approaches, we aim to develop a more effective and reliable method for quantitative analysis of virtually stained microscopic images, ultimately enhancing the study of microorganisms and cells at the subcellular level.


Assuntos
Algoritmos , Sêmen , Masculino , Humanos , Reprodutibilidade dos Testes , Espermatozoides , Coloração e Rotulagem , Processamento de Imagem Assistida por Computador/métodos
3.
Lab Chip ; 23(11): 2640-2653, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37183761

RESUMO

Hydrodynamic cavitation (HC) is a phase change phenomenon, where energy release in a fluid occurs upon the collapse of bubbles, which form due to the low local pressures. During recent years, due to advances in lab-on-a-chip technologies, HC-on-a-chip (HCOC) and its potential applications have attracted considerable interest. Microfluidic devices enable the performance of controlled experiments by enabling spatial control over the cavitation process and by precisely monitoring its evolution. In this study, we propose the adjunctive use of HC to induce distinct zones of cellular injury and enhance the anticancer efficacy of Doxorubicin (DOX). HC caused different regions (lysis, necrosis, permeabilization, and unaffected regions) upon exposure of different cancer and normal cells to HC. Moreover, HC was also applied to the confluent cell monolayer following the DOX treatment. Here, it was shown that the combination of DOX and HC exhibited a more pronounced anticancer activity on cancer cells than DOX alone. The effect of HC on cell permeabilization was also proven by using carbon dots (CDs). Finally, the cell stiffness parameter, which was associated with cell proliferation, migration and metastasis, was investigated with the use of cancer cells and normal cells under HC exposure. The HCOC offers the advantage of creating well-defined zones of bio-responses upon HC exposure simultaneously within minutes, achieving cell lysis and molecular delivery through permeabilization by providing spatial control. In conclusion, micro scale hydrodynamic cavitation proposes a promising alternative to be used to increase the therapeutic efficacy of anticancer drugs.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Hidrodinâmica , Sistemas de Liberação de Medicamentos , Doxorrubicina/farmacologia , Antineoplásicos/farmacologia
4.
Curr Probl Cardiol ; 48(2): 101482, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36336117

RESUMO

Treadmill Exercise Test (TET) results and patients' clinical symptoms influence cardiologists' decision to perform Coronary Angiography (CAG) which is an invasive procedure. Since TET has high false positive rates, it can cause an unnecessary invasive CAG. Our primary objective was to develop a machine learning model capable of optimizing TET performance based on electrocardiography (ECG) waves characteristics and signals. TET reports from 294 patients who underwent CAG following high risk TET were collected and categorized into those with critical CAD and others. The signal was converted to time series format. A dataset containing the P, QRS, and T wave times and amplitudes was created. Using this dataset, 5 machine learning algorithms were trained with 5-fold cross validation. All these models were then compared to the performance of cardiologists on V5 signal. The results from 5 machine learning models were clearly superior to the cardiologists' V5 signal performance (P < 0.0001). In addition, the XGBoost model, with an accuracy of 80.92±6.42% and an area under the curve (AUC) of 0.78±0.06, was the most successful model. Machine learning models can produce high-performance diagnoses using the V5 signal markers only as it does not require any clinical markers obtained from TET reports. This can lead to significant contributions to improving clinical prediction in non-invasive methods.


Assuntos
Doença da Artéria Coronariana , Humanos , Doença da Artéria Coronariana/diagnóstico , Teste de Esforço/métodos , Angiografia Coronária , Eletrocardiografia , Aprendizado de Máquina
5.
Nat Commun ; 13(1): 7351, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446776

RESUMO

Accurate assessment of cell stiffness distribution is essential due to the critical role of cell mechanobiology in regulation of vital cellular processes like proliferation, adhesion, migration, and motility. Stiffness provides critical information in understanding onset and progress of various diseases, including metastasis and differentiation of cancer. Atomic force microscopy and optical trapping set the gold standard in stiffness measurements. However, their widespread use has been hampered with long processing times, unreliable contact point determination, physical damage to cells, and unsuitability for multiple cell analysis. Here, we demonstrate a simple, fast, label-free, and high-resolution technique using acoustic stimulation and holographic imaging to reconstruct stiffness maps of single cells. We used this acousto-holographic method to determine stiffness maps of HCT116 and CTC-mimicking HCT116 cells and differentiate between them. Our system would enable widespread use of whole-cell stiffness measurements in clinical and research settings for cancer studies, disease modeling, drug testing, and diagnostics.


Assuntos
Holografia , Pinças Ópticas , Estimulação Acústica , Biofísica , Diferenciação Celular
6.
J Clin Med ; 11(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36079042

RESUMO

Dermoscopy is the visual examination of the skin under a polarized or non-polarized light source. By using dermoscopic equipment, many lesion patterns that are invisible under visible light can be clearly distinguished. Thus, more accurate decisions can be made regarding the treatment of skin lesions. The use of images collected from a dermoscope has both increased the performance of human examiners and allowed the development of deep learning models. The availability of large-scale dermoscopic datasets has allowed the development of deep learning models that can classify skin lesions with high accuracy. However, most dermoscopic datasets contain images that were collected from digital dermoscopic devices, as these devices are frequently used for clinical examination. However, dermatologists also often use non-digital hand-held (optomechanical) dermoscopes. This study presents a dataset consisting of dermoscopic images taken using a mobile phone-attached hand-held dermoscope. Four deep learning models based on the MobileNetV1, MobileNetV2, NASNetMobile, and Xception architectures have been developed to classify eight different lesion types using this dataset. The number of images in the dataset was increased with different data augmentation methods. The models were initialized with weights that were pre-trained on the ImageNet dataset, and then they were further fine-tuned using the presented dataset. The most successful models on the unseen test data, MobileNetV2 and Xception, had performances of 89.18% and 89.64%. The results were evaluated with the 5-fold cross-validation method and compared. Our method allows for automated examination of dermoscopic images taken with mobile phone-attached hand-held dermoscopes.

7.
J Biosci Bioeng ; 134(5): 462-470, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36100518

RESUMO

Coriander (Coriandrum sativum L.), one of the oldest spice plants globally, has wide usage, mainly owing to its essential oil content. This study investigated the effects of rhizobacteria, mycorrhizae, and their combination on the yield and essential oil profile of coriander. The treatments resulted in statistically higher yield properties and essential oil values than the control. The effects of the microorganism treatments on the yield characteristics were not statistically different. However, the treatments significantly affected the essential oil content and yield. While the arbuscular mycorrhizal fungi and combined application of the microorganisms were statistically equal, arbuscular mycorrhizal fungi had a higher value in essential oil content and yield by 0.75% and 11.8 L ha-1, respectively. The combined application resulted in higher values of linalool (9.47%) and γ-terpinene (6.75%), the components with the highest rate in the essential oil composition. The principal component analysis highlighted the importance of the combined application on the crucial components. In the light of the results, beneficial microorganism treatments were considered significant for yield and essential oil enhancement. Therefore, the wide use of these treatments will highly contribute to coriander cultivation.


Assuntos
Inoculantes Agrícolas , Coriandrum , Óleos Voláteis , Óleos Voláteis/farmacologia
8.
Mycoses ; 65(12): 1119-1126, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35842749

RESUMO

BACKGROUND: The diagnosis of superficial fungal infections is still mostly based on direct microscopic examination with potassium hydroxide solution. However, this method can be time consuming, and its diagnostic accuracy rates vary widely depending on the clinician's experience. OBJECTIVES: This study presents a deep neural network structure that enables the rapid solutions for these problems and can perform automatic fungi detection in grayscale images without dyes. METHODS: One hundred sixty microscopic full field photographs containing the fungal element, obtained from patients with onychomycosis, and 297 microscopic full field photographs containing dissolved keratin obtained from normal nails were collected. Smaller patches containing fungi (n = 1835) and keratin (n = 5238) were extracted from these full field images. In order to detect fungus and keratin, VGG16 and InceptionV3 models were developed by the use of these patches. The diagnostic performance of models was compared with 16 dermatologists by using 200 test patches. RESULTS: For the VGG16 model, the InceptionV3 model and 16 dermatologists, mean accuracy rates were 88.10 ± 0.8%, 88.78 ± 0.35% and 74.53 ± 8.57%, respectively; mean sensitivity rates were 75.04 ± 2.73%, 74.93 ± 4.52% and 74.81 ± 19.51%, respectively; and mean specificity rates were 92.67 ± 1.17%, 93.78 ± 1.74% and 74.25 ± 18.03%, respectively. The models were statistically superior to dermatologists according to rates of accuracy and specificity but not to sensitivity (p < .0001, p < .005 and p > .05, respectively). Area under curve values of the VGG16 and InceptionV3 models were 0.9339 and 0.9292, respectively. CONCLUSION: Our research demonstrates that it is possible to build an automated system capable of detecting fungi present in microscopic images employing the proposed deep learning models. It has great potential for fungal detection applications based on AI.


Assuntos
Onicomicose , Humanos , Onicomicose/diagnóstico , Onicomicose/microbiologia , Sensibilidade e Especificidade , Redes Neurais de Computação , Queratinas
9.
IEEE Trans Biomed Eng ; 69(1): 513-524, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329154

RESUMO

OBJECTIVE: Hydrodynamic cavitation is characterized by the formation of bubbles inside a flow due to local reduction of pressure below the saturation vapor pressure. The resulting growth and violent collapse of bubbles lead to a huge amount of released energy. This energy can be implemented in different fields such as heat transfer enhancement, wastewater treatment and chemical reactions. In this study, a cystoscope based on small scale hydrodynamic cavitation was designed and fabricated to exploit the destructive energy of cavitation bubbles for treatment of tumor tissues. The developed device is equipped with a control system, which regulates the movement of the cystoscope in different directions. According to our experiments, the fabricated cystoscope was able to locate the target and expose cavitating flow to the target continuously and accurately. The designed cavitation probe embedded into the cystoscope caused a significant damage to prostate cancer and bladder cancer tissues within less than 15 minutes. The results of our experiments showed that the cavitation probe could be easily coupled with endoscopic devices because of its small diameter. We successfully integrated a biomedical camera, a suction tube, tendon cables, and the cavitation probe into a 6.7 mm diameter cystoscope, which could be controlled smoothly and accurately via a control system. The developed device is considered as a mechanical ablation therapy, can be a solid alternative for minimally invasive tissue ablation methods such as radiofrequency (RF) and laser ablation, and could have lower side effects compared to ultrasound therapy and cryoablation.


Assuntos
Técnicas de Ablação , Neoplasias da Próstata , Cistoscópios , Humanos , Hidrodinâmica , Masculino , Ondas de Rádio
10.
Mol Biol Rep ; 48(5): 4537-4547, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34148209

RESUMO

Laurel (Laurus nobilis L.) has been used in the Mediterranean basin since ancient ages. Nowadays, Turkey, Mexico, Portugal, Italy, Spain, France, Algeria, and Morocco use aromatic leaves for commercial purposes, and Turkey is the largest exporter in the world. In this study, molecular characterization, and genetic relationships of 94 Turkish laurel genotypes were determined by ISSR and SCoT markers. The experiment was conducted with 16 ISSR and 10 SCoT markers. While 348 of 373 bands were polymorphic with a 93.3% polymorphism rate, Nei's genetic distances ranged between 0.17 and 0.70 with 0.39 mean in ISSR. In SCoT, 175 of 227 bands were polymorphic with 77.1% polymorphism rate, and Nei's genetic distances varied between 0.12 and 0.51. Sufficient genetic diversity determined with diversity parameters consisting of the average Shannon's information index (ISSR: 0.46, SCoT:0.35), the overall gene diversity (ISSR:0.19, SCoT:0.18), and the effective number of alleles (ISSR:1.52, SCoT:1.38). AMOVA (Analysis of molecular variance) revealed most of the variation was within genotypes (96%). Neighbor-joining algorithms, principal coordinate analysis (PCoA), and model-based structure resulted in harmony and clustered according to the geographical regions and provinces they collected. Genotypes were divided into two groups in ISSR and SCoT with UPGMA clustering resulting in a similar polymorphism distribution. The correlation coefficient (r) determined by marker systems' Nei's genetic distances was 0.25. The results of the study put forward resources for advanced breeding techniques, contribute to the preservation of genetic diversity, and management of genetic resources for the breeders.


Assuntos
Variação Genética/genética , Laurus/genética , Repetições de Microssatélites/genética , Filogenia , Alelos , Marcadores Genéticos , Genótipo , Turquia
11.
PLoS One ; 14(2): e0211985, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30807571

RESUMO

Safflower (Carthamus tinctorius L.) is a multipurpose crop of dry land yielding very high quality of edible oil. Present study was aimed to investigate the genetic diversity and population structure of 131 safflower accessions originating from 28 different countries using 13 iPBS-retrotransposon markers. A total of 295 iPBS bands were observed among which 275 (93.22%) were found polymorphic. Mean Polymorphism information content (0.48) and diversity parameters including mean effective number of alleles (1.33), mean Shannon's information index (0.33), overall gene diversity (0.19), Fstatistic (0.21), and inbreeding coefficient (1.00) reflected the presence of sufficient amount of genetic diversity in the studied plant materials. Analysis of molecular variance (AMOVA) showed that more than 40% of genetic variation was derived from populations. Model-based structure, principal coordinate analysis (PCoA) and unweighted pair-group method with arithmetic means (UPGMA) algorithms clustered the 131 safflower accessions into four main populations A, B, C, D and an unclassified population, with no meaningful geographical origin. Most diverse accessions originated from Asian countries including Afghanistan, Pakistan, China, Turkey, and India. Four accessions, Turkey3, Afghanistan4, Afghanistan2, and Pakistan24 were found most genetically distant and might be recommended as a candidate parents for breeding purposes. The findings of this study are most probably supported by the seven similarity centers hypothesis of safflower. This is a first study to explore the genetic diversity and population structure in safflower accessions using the iPBS-retrotransposon markers. The information provided in this work will therefore be helpful for scientists interested in safflower breeding.


Assuntos
Carthamus tinctorius/classificação , Elementos de DNA Transponíveis , Retroelementos , Afeganistão , Carthamus tinctorius/genética , China , DNA de Plantas/genética , Variação Genética , Genética Populacional , Índia , Paquistão , Filogeografia , Turquia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...