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1.
Cancer Cytopathol ; 130(11): 872-880, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35727052

RESUMO

BACKGROUND: The Paris System for Reporting Urinary Cytology (TPS) has been shown to improve bladder cancer diagnosis. Advances in artificial intelligence (AI) may assist and improve the clinical workflow by applying TPS in routine diagnostic services. METHODS: A deep-learning-based algorithm was developed to identify urothelial cancer candidate cells using whole-slide images (WSIs). In the testing cohort, 131 urine cytology slides were retrospectively retrieved and analyzed using this AI algorithm. The authors compared the performance of one cytopathologist and two cytotechnologists using AI-assisted digital urine cytology. Then, the AI-assisted WSIs were evaluated in the clinical workflow. The cytopathologist first made a diagnosis by reviewing the AI-inferred WSIs and quantitative data (nuclear-to-cytoplasmic ratio and nuclear size) for each sample. After a washout period, the same cytopathologist made a diagnosis for the same samples using direct microscopy. All diagnosis results were compared with the expert panel consensus. RESULTS: The AI-assisted diagnosis by the two cytotechnologists and the one cytopathologist demonstrated performance results that were comparable to the expert panel consensus (sensitivity, 79.5% and 82.1% vs. 92.3%, respectively; specificity, 100% and 98.9% vs. 100%, respectively). Furthermore, the performance of the AI-assisted WSIs compared with the microscopic diagnosis by the cytopathologist demonstrated superior sensitivity (92.3% vs. 87.2%) and negative predictive value (96.8% vs. 94.8%). In addition, the AI-assisted reporting demonstrated near perfect agreement with the expert panel consensus (κ = 0.944) and the microscopic diagnosis (κ = 0.862). CONCLUSIONS: The AI algorithm developed by the authors effectively assisted TPS-based reporting by providing AI-inferred WSIs and quantitative data.


Assuntos
Inteligência Artificial , Neoplasias Urológicas , Humanos , Projetos Piloto , Estudos Retrospectivos , Citodiagnóstico/métodos , Algoritmos , Neoplasias Urológicas/diagnóstico , Urina , Urotélio/patologia
2.
Opt Express ; 30(9): 14759-14769, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473213

RESUMO

3D printing techniques have great potential in the direct fabrication of microfluidic and many kinds of molds, such as dental and jewelry models. However, the resolution, surface roughness, and critical dimension uniformity of 3D printing objects are still a challenge for improvement. In this article, we proposed a 405nm light emitting diode (LED) backlight module based on stacks of structured films, and the full width half maximum (FWHM) of the angular distribution of this module is reduced to less than ± 15°. Compared with the commercial lens array optical module, the ten points intensity uniformity of an 8.9" build area is improved from 56% to 80%. Moreover, we found that the surface roughness and the sharpness of the edge of the printing objects are also obviously improved by our novel quasi-collimated LED backlight module. These features give us a promising way for the application of microfluidics and micro-optics components in the future.

3.
Toxicology ; 377: 64-72, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27915097

RESUMO

Lead exposure has been associated with several defective skeletal growth processes and bone mineral alterations. The aim of the present study is to make a more detailed description of the toxic effects of lead intoxication on bone intrinsic material properties as mineral composition, morphology and microstructural characteristics. For this purpose, Wistar rats were exposed (n=12) to 1000ppm lead acetate in drinking water for 90days while control group (n=8) were treated with sodium acetate. Femurs were examined using inductively coupled plasma optical emission spectrometry (ICP-OES), Attenuated Total Reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and micro-Computed Tomography (µCT). Results showed that femur from the lead-exposed rats had higher carbonate content in bone mineral and (Ca2++Mg2++ Na+)/P ratio values, although no variations were observed in crystal maturity and crystallite size. From morphological analyses, lead exposure rats showed a decreased in trabecular bone surface and distribution while trabecular thickness and cortical area increased. These overall effects indicate a similar mechanism of bone maturation normally associated to age-related processes. These responses are correlated with the adverse actions induced by lead on the processes regulating bone turnover mechanism. This information may explain the osteoporosis diseases associated to lead intoxication as well as the risk of fracture observed in populations exposed to this toxicant.


Assuntos
Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Fêmur/efeitos dos fármacos , Fêmur/crescimento & desenvolvimento , Chumbo/administração & dosagem , Chumbo/toxicidade , Animais , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Feminino , Fêmur/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
4.
Exp Toxicol Pathol ; 68(1): 47-53, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26422677

RESUMO

Lead (Pb) is a persistent environmental contaminant that is mainly stored in bones being an important source of endogenous lead exposure during periods of increased bone resorption as occurs in menopause. As no evidence exists of which bone biomechanical properties are impaired in those elderly women who had been exposed to Pb during their lifetime, the aim of the present study is to discern whether chronic lead poisoning magnifies the deterioration of bone biology that occurs in later stages of life. We investigated the effect of Pb in the femora of ovariectomized (OVX) female Wistar rats who had been intoxicated with 1000 ppm of Pb acetate in drinking water for 8 months. Structural properties were determined using a three-point bending mechanical test, and geometrical and material properties were evaluated after obtaining the load/deformation curve. Areal Bone Mineral Density (BMD) was estimated using a bone densitometer. Femoral histomorphometry was carried out on slices dyed with H&E (Hematoxylin and Eosin). Pb and OVX decreased all structural properties with a higher effect when both treatments were applied together. Medullar and cortical area of femurs under OVX increased, allowing the bone to accommodate its architecture, which was not observed under Pb intoxication. Pb and OVX significantly decreased BMD, showing lead treated ovariectomized rats (PbOVX) animals the lowest BMD levels. Trabecular bone volume per total volume (BV/TV%) was decreased in OVX and PbOVX animals in 54% compared to the control animals (p<0.001). Pb femurs also showed 28% less trabeculae than the control (p<0.05). We demonstrated that Pb intoxication magnifies the impairment in bone biomechanics of OVX rats with a consequent enhancement of the risk of fracture. These results enable the discussion of the detrimental effects of lead intoxication in bone biology in elderly women.


Assuntos
Osso e Ossos/patologia , Osso e Ossos/fisiopatologia , Intoxicação por Chumbo/complicações , Compostos Organometálicos/toxicidade , Osteoporose Pós-Menopausa/complicações , Absorciometria de Fóton , Animais , Fenômenos Biomecânicos , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Humanos , Ovariectomia , Ratos , Ratos Wistar
5.
PLoS Genet ; 11(10): e1005580, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26492166

RESUMO

Ribosome biogenesis takes place in the nucleolus, the size of which is often coordinated with cell growth and development. However, how metazoans control nucleolar size remains largely unknown. Caenorhabditis elegans provides a good model to address this question owing to distinct tissue distribution of nucleolar sizes and a mutant, ncl-1, which exhibits larger nucleoli than wild-type worms. Here, through a series of loss-of-function analyses, we report that the nucleolar size is regulated by a circuitry composed of microRNA let-7, translation repressor NCL-1, and a major nucleolar pre-rRNA processing protein FIB-1/fibrillarin. In cooperation with RNA binding proteins PUF and NOS, NCL-1 suppressed the translation of FIB-1/fibrillarin, while let-7 targeted the 3'UTR of ncl-1 and inhibited its expression. Consequently, the abundance of FIB-1 is tightly controlled and correlated with the nucleolar size. Together, our findings highlight a novel genetic cascade by which post-transcriptional regulators interplay in developmental control of nucleolar size and function.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Proteínas de Transporte/genética , Proteínas Cromossômicas não Histona/genética , MicroRNAs/genética , RNA Ribossômico/genética , Proteínas Ribossômicas/genética , Ribossomos/genética , Regiões 3' não Traduzidas , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Transporte/metabolismo , Nucléolo Celular/genética , Tamanho Celular , Proteínas Cromossômicas não Histona/metabolismo , Feminino , MicroRNAs/metabolismo , Imagem Óptica , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Vulva/crescimento & desenvolvimento , Vulva/metabolismo
6.
Bull Environ Contam Toxicol ; 88(6): 1033-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22456729

RESUMO

The existence of children living at high altitude suffering from lead (Pb) poisoning prompted us to investigate the long term effects of this pollutant on growth and bone biology in growing rats maintained at simulated high altitude (SHA). Pb and hypoxia (HX) significantly reduced body weight (-9.4 % and -24 %; p < 0.01) and length (-3 % and -8 %; p < 0.01); decreased femoral ultimate load (-16 % and -40 %; p < 0.01) and femoral energy absorption capacity (-18 % and -74 %; p < 0.01). Oral pathologic alterations were observed in experimental groups. Our findings revealed growth retardation and damages on femoral and mandibular bones that predispose to fractures.


Assuntos
Altitude , Desenvolvimento Ósseo/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Crescimento e Desenvolvimento/efeitos dos fármacos , Chumbo/toxicidade , Animais , Osso e Ossos/fisiologia , Feminino , Ratos , Ratos Wistar
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