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1.
Expert Rev Mol Diagn ; 21(1): 109-118, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33355491

RESUMO

OBJECTIVES: To assess a recently described CNN (convolutional neural network) DARC (Detection of Apoptosing Retinal Cells) algorithm in predicting new Subretinal Fluid (SRF) formation in Age-related-Macular-Degeneration (AMD). METHODS: Anonymized DARC, baseline and serial OCT images (n = 427) from 29 AMD eyes of Phase 2 clinical trial (ISRCTN10751859) were assessed with CNN algorithms, enabling the location of each DARC spot on corresponding OCT slices (n = 20,629). Assessment of DARC in a rabbit model of angiogenesis was performed in parallel. RESULTS: A CNN DARC count >5 at baseline was significantly (p = 0.0156) related to development of new SRF throughout 36 months. Prediction rate of eyes using unique DARC spots overlying new SRF had positive predictive values, sensitivities and specificities >70%, with DARC count significantly (p < 0.005) related to the magnitude of SRF accumulation at all time points. DARC identified earliest stages of angiogenesis in-vivo. CONCLUSIONS: DARC was able to predict new wet-AMD activity. Using only an OCT-CNN definition of new SRF, we demonstrate that DARC can identify early endothelial neovascular activity, as confirmed by rabbit studies. Although larger validation studies are required, this shows the potential of DARC as a biomarker of wet AMD, and potentially saving vision-loss.


Assuntos
Apoptose , Degeneração Macular/diagnóstico , Degeneração Macular/patologia , Redes Neurais de Computação , Retina/patologia , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Masculino , Coelhos
2.
Expert Rev Mol Diagn ; 20(7): 737-748, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32310684

RESUMO

BACKGROUND: A key objective in glaucoma is to identify those at risk of rapid progression and blindness. Recently, a novel first-in-man method for visualising apoptotic retinal cells called DARC (Detection-of-Apoptosing-Retinal-Cells) was reported. The aim was to develop an automatic CNN-aided method of DARC spot detection to enable prediction of glaucoma progression. METHODS: Anonymised DARC images were acquired from healthy control (n=40) and glaucoma (n=20) Phase 2 clinical trial subjects (ISRCTN10751859) from which 5 observers manually counted spots. The CNN-aided algorithm was trained and validated using manual counts from control subjects, and then tested on glaucoma eyes. RESULTS: The algorithm had 97.0% accuracy, 91.1% sensitivity and 97.1% specificity to spot detection when compared to manual grading of 50% controls.  It was next tested on glaucoma patient eyes defined as progressing or stable based on a significant (p<0.05) rate of progression using OCT-retinal nerve fibre layer measurements at 18 months. It demonstrated 85.7% sensitivity, 91.7% specificity with AUC of 0.89, and a significantly (p=0.0044) greater DARC count in those patients who later progressed. CONCLUSION: This CNN-enabled algorithm provides an automated and objective measure of DARC, promoting its use as an AI-aided biomarker for predicting glaucoma progression and testing new drugs.


Assuntos
Algoritmos , Apoptose , Glaucoma/patologia , Redes Neurais de Computação , Células Ganglionares da Retina/patologia , Adulto , Idoso , Anexina A5/administração & dosagem , Automação , Ensaios Clínicos Fase II como Assunto , Progressão da Doença , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Tomografia de Coerência Óptica
3.
Am J Epidemiol ; 178(3): 350-8, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23828249

RESUMO

Tetrafluoroethylene (TFE), a compound used for the production of fluorinated polymers including polytetrafluoroethylene, increases the incidence of liver and kidney cancers and leukemia in rats and mice. This is the first time the cancer risk in humans has been explored comprehensively in a cohort mortality study (1950-2008) that included all polytetrafluoroethylene production sites in Europe and North America at the time it was initiated. A job-exposure matrix (1950-2002) was developed for TFE and ammonium perfluoro-octanoate, a chemical used in the polymerization process. National reference rates were used to calculate standardized mortality ratios (SMRs) and 95% confidence intervals. Among 4,773 workers ever exposed to TFE, we found a lower rate of death from most causes, as well as increased risks for cancer of the liver (SMR = 1.27; 95% confidence interval: 0.55, 2.51; 8 deaths) and kidney (SMR = 1.44; 95% confidence interval: 0.69, 2.65; 10 deaths) and for leukemia (SMR = 1.48; 95% confidence interval: 0.77, 2.59; 12 deaths). A nonsignificant upward trend (P = 0.24) by cumulative exposure to TFE was observed for liver cancer. TFE and ammonium perfluoro-octanoate exposures were highly correlated, and therefore their separate effects could not be disentangled. This pattern of findings narrows the range of uncertainty on potential TFE carcinogenicity but cannot conclusively confirm or refute the hypothesis that TFE is carcinogenic to humans.


Assuntos
Indústria Química , Fluorocarbonos/efeitos adversos , Neoplasias Renais/mortalidade , Leucemia/mortalidade , Neoplasias Hepáticas/mortalidade , Doenças Profissionais/induzido quimicamente , Doenças Profissionais/mortalidade , Exposição Ocupacional/análise , Causas de Morte , Estudos de Coortes , Monitoramento Ambiental/estatística & dados numéricos , Europa (Continente)/epidemiologia , Feminino , Fluorocarbonos/análise , Fluorocarbonos/síntese química , Humanos , Nefropatias/mortalidade , Neoplasias Renais/induzido quimicamente , Leucemia/induzido quimicamente , Hepatopatias/mortalidade , Neoplasias Hepáticas/induzido quimicamente , Masculino , Polimerização , Medição de Risco , Taxa de Sobrevida , Estados Unidos/epidemiologia
4.
Biomacromolecules ; 14(3): 672-82, 2013 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-23350530

RESUMO

PLGA nanoparticles are among the most studied polymer nanoformulations for several drugs against different kinds of malignant diseases, thanks to their in vivo stability and tumor localization exploiting the well-documented "enhanced permeation and retention" (EPR) effect. In this paper, we have developed uniform curcumin-bearing PLGA nanoparticles by a single-emulsion process, which exhibited a curcumin release following a Fickian-law diffusion over 10 days in vitro. PLGA nanoparticles were about 120 nm in size, as determined by dynamic light scattering, with a surface negative charge of -30 mV. The loading ratio of encapsulated drug in our PLGA nanoformulation was 8 wt%. PLGA encapsulation provided efficient protection of curcumin from environment, as determined by fluorescence emission experiments. Next, we have investigated the possibility to study the intracellular degradation of nanoparticles associated with a specific G2/M blocking effect on MCF7 breast cancer cells caused by curcumin release in the cytoplasm, which provided direct evidence on the mechanism of action of our nanocomplex. This study was carried out using Annexin V-based cell death analysis, MTT assessment of proliferation, flow cytometry, and confocal laser scanning microscopy. PLGA nanoparticles proved to be completely safe, suggesting a potential utilization of this nanocomplex to improve the intrinsically poor bioavailability of curcumin for the treatment of severe malignant breast cancer.


Assuntos
Materiais Biocompatíveis/química , Neoplasias da Mama/metabolismo , Curcumina/farmacocinética , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Apoptose/efeitos dos fármacos , Disponibilidade Biológica , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Células MCF-7 , Microscopia Confocal , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
5.
Am J Perinatol ; 30(1): 25-32, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22773282

RESUMO

BACKGROUND: Human milk feeding protects against oxidative stress-induced damage in preterm neonates, including severe multifactorial diseases such as retinopathy of prematurity (ROP), necrotizing enterocolitis (NEC), and bronchopulmonary dysplasia (BPD). The carotenoids, which are not found in formula milk, might play a key role in these actions. METHODS: A multicenter, double-blind, randomized controlled trial was conducted in three tertiary Italian neonatal intensive care units. All preterm infants < 32(+6) weeks' gestational age were eligible and were randomized to a single, oral, daily 0.5-mL dose of carotenoid supplementation (0.14 mg lutein + 0.0006 mg zeaxanthin) or placebo (5% glucose solution) from birth till 36 weeks' corrected gestational age. Primary outcomes were threshold ROP, NEC > second stage, and BPD. Surveillance for detection of these diseases and for intolerance/adverse effects was performed. RESULTS: No treatment-related adverse effect was documented in the 229 analyzed infants, whose clinical/demographical characteristics were similar in the two groups. Threshold ROP incidence did not significantly differ in treated (6.2%) versus not treated infants (10.3%; p = 0.18). The same occurred for NEC (1.7% versus 5.1%; p = 0.15) and BPD (4.5% versus 10.3%; p = 0.07). Noteworthy, the progression rate from early ROP stages to threshold ROP was decreased by 50% (0.30 versus 0.44; p = 0.23). CONCLUSION: Lutein/zeaxanthin supplementation in preterm infants is well tolerated. No significant effect was seen on threshold ROP, NEC, or BPD. The decreasing trends of these outcomes in the treatment group need to be assessed and confirmed on larger sample-sizes.


Assuntos
Displasia Broncopulmonar/prevenção & controle , Suplementos Nutricionais , Enterocolite Necrosante/prevenção & controle , Luteína/uso terapêutico , Retinopatia da Prematuridade/prevenção & controle , Xantofilas/uso terapêutico , Progressão da Doença , Método Duplo-Cego , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Terapia Intensiva Neonatal , Luteína/efeitos adversos , Masculino , Xantofilas/efeitos adversos , Zeaxantinas
6.
Acta Biomed ; 83 Suppl 1: 27-32, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23029874

RESUMO

Exogenous surfactant is a therapeutic option for newborns, children and adults with acute respiratory distress disorders. Although tracheal instillation is still reputed as the classical method of surfactant delivery, alternative techniques have been investigated. Surfactant administration by using thin intra-tracheal catheters, bronchoscopy, laryngeal mask airway, or nebulisation, although variably effective, appear to be less invasive when compared to tracheal intubation. However, further research is still needed to better clarify this matter. (www.actabiomedica.it).


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Surfactantes Pulmonares/administração & dosagem , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , Adulto , Criança , Humanos , Recém-Nascido , Intubação Intratraqueal , Máscaras Laríngeas , Nebulizadores e Vaporizadores
7.
Proc Natl Acad Sci U S A ; 108(3): 1104-9, 2011 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-21189302

RESUMO

A recent body of evidence indicates an active role for stromal (mis)-regulation in the progression of neoplasias. Within this conceptual framework, genes belonging to the growing but still poorly characterized class of tumor antagonizing/malignancy suppressor genes (TAG/MSG) seem to play a crucial role in the regulation of the cross-talk between stromal and epithelial cells by controlling malignant growth in vivo without affecting any cancer-related phenotype in vitro. Here, we have functionally characterized the human RNASET2 gene, which encodes the first human member of the widespread Rh/T2/S family of extracellular RNases and was recently found to be down-regulated at the transcript level in several primary ovarian tumors or cell lines and in melanoma cell lines. Although we could not detect any activity for RNASET2 in several functional in vitro assays, a remarkable control of ovarian tumorigenesis could be detected in vivo. Moreover, the control of ovarian tumorigenesis mediated by this unique tumor suppressor gene occurs through modification of the cellular microenvironment and the induction of immunocompetent cells of the monocyte/macrophage lineage. Taken together, the data presented in this work strongly indicate RNASET2 as a previously unexplored member of the growing family of tumor-antagonizing genes.


Assuntos
Macrófagos/imunologia , Neoplasias Ovarianas/genética , Ribonucleases/imunologia , Proteínas Supressoras de Tumor/imunologia , Análise de Variância , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Hibridização In Situ , Técnicas In Vitro , Camundongos , Camundongos Nus , Neoplasias Ovarianas/patologia , Ribonucleases/genética , Proteínas Supressoras de Tumor/genética , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Mol Biol Cell ; 18(4): 1282-92, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17267687

RESUMO

Mammalian cleavage factor I (CF Im) is an essential factor that is required for the first step in pre-mRNA 3' end processing. Here, we characterize CF Im68 subnuclear distribution and mobility. Fluorescence microscopy reveals that in addition to paraspeckles CF Im68 accumulates in structures that partially overlap with nuclear speckles. Analysis of synchronized cells shows that CF Im68 distribution in speckles and paraspeckles varies during the cell cycle. At an ultrastructural level, CF Im68 is associated with perichromatin fibrils, the sites of active transcription, and concentrates in interchromatin granules-associated zones. We show that CFIm68 colocalizes with bromouridine, RNA polymerase II, and the splicing factor SC35. On inhibition of transcription, endogenous CF Im68 no longer associates with perichromatin fibrils, but it can still be detected in interchromatin granules-associated zones. These observations support the idea that not only splicing but also 3' end processing occurs cotranscriptionally. Finally, fluorescence recovery after photobleaching analysis reveals that the CF Im68 fraction associated with paraspeckles moves at a rate similar to the more dispersed molecules in the nucleoplasm, demonstrating the dynamic nature of this compartment. These findings suggest that paraspeckles are a functional compartment involved in RNA metabolism in the cell nucleus.


Assuntos
Estruturas do Núcleo Celular/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo , Motivos de Aminoácidos , Animais , Bromouracila/análogos & derivados , Cromatina/metabolismo , Cromatina/ultraestrutura , Diclororribofuranosilbenzimidazol/farmacologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HeLa/efeitos dos fármacos , Humanos , Mamíferos , Microscopia Eletrônica/métodos , Mutação , Proteínas Nucleares/metabolismo , Fotodegradação , Subunidades Proteicas , RNA/metabolismo , RNA Polimerase II/metabolismo , Ribonucleoproteínas/metabolismo , Fatores de Processamento de Serina-Arginina , Transcrição Gênica , Uridina/análogos & derivados , Uridina/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/efeitos dos fármacos , Fatores de Poliadenilação e Clivagem de mRNA/genética
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