Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Mais filtros

Base de dados
Intervalo de ano de publicação
Nat Commun ; 12(1): 4884, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385460


Pathology is practiced by visual inspection of histochemically stained tissue slides. While the hematoxylin and eosin (H&E) stain is most commonly used, special stains can provide additional contrast to different tissue components. Here, we demonstrate the utility of supervised learning-based computational stain transformation from H&E to special stains (Masson's Trichrome, periodic acid-Schiff and Jones silver stain) using kidney needle core biopsy tissue sections. Based on the evaluation by three renal pathologists, followed by adjudication by a fourth pathologist, we show that the generation of virtual special stains from existing H&E images improves the diagnosis of several non-neoplastic kidney diseases, sampled from 58 unique subjects (P = 0.0095). A second study found that the quality of the computationally generated special stains was statistically equivalent to those which were histochemically stained. This stain-to-stain transformation framework can improve preliminary diagnoses when additional special stains are needed, also providing significant savings in time and cost.

Biópsia com Agulha de Grande Calibre/métodos , Aprendizado Profundo , Diagnóstico por Computador/métodos , Nefropatias/patologia , Rim/patologia , Coloração e Rotulagem/métodos , Algoritmos , Corantes/química , Corantes/classificação , Corantes/normas , Diagnóstico Diferencial , Humanos , Nefropatias/diagnóstico , Patologia Clínica/métodos , Patologia Clínica/normas , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Coloração e Rotulagem/normas
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33597293


Emerging evidence suggests that intratumoral interferon (IFN) signaling can trigger targetable vulnerabilities. A hallmark of pancreatic ductal adenocarcinoma (PDAC) is its extensively reprogrammed metabolic network, in which nicotinamide adenine dinucleotide (NAD) and its reduced form, NADH, are critical cofactors. Here, we show that IFN signaling, present in a subset of PDAC tumors, substantially lowers NAD(H) levels through up-regulating the expression of NAD-consuming enzymes PARP9, PARP10, and PARP14. Their individual contributions to this mechanism in PDAC have not been previously delineated. Nicotinamide phosphoribosyltransferase (NAMPT) is the rate-limiting enzyme in the NAD salvage pathway, a dominant source of NAD in cancer cells. We found that IFN-induced NAD consumption increased dependence upon NAMPT for its role in recycling NAM to salvage NAD pools, thus sensitizing PDAC cells to pharmacologic NAMPT inhibition. Their combination decreased PDAC cell proliferation and invasion in vitro and suppressed orthotopic tumor growth and liver metastases in vivo.

Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/patologia , Citocinas/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica , Interferon Tipo I/metabolismo , NAD/deficiência , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Neoplasias Pancreáticas/patologia , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Proliferação de Células , Citocinas/genética , Citocinas/metabolismo , Humanos , Interferon Tipo I/genética , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
Virology ; 522: 228-233, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30053656


Zika virus (ZIKV) has been identified as a cause of neurologic diseases in infants and Guillain-Barré Syndrome, and currently, no therapeutics or vaccines are approved. In this study, we sought to identify potential host proteins interacting with ZIKV particles to gain better insights into viral infectivity. Viral particles were purified through density-gradient centrifugation and subsequently, size-exclusion chromatography (SEC). Mass spectrometric analyses revealed viral envelope protein and HSP70 to comigrate in only one SEC fraction. Neither of these proteins were found in any other SEC fractions. We then performed neutralization assays and found that incubating viral particles with antibody against HSP70 indeed significantly reduced viral infectivity, while HSC70 antibody did not. Preincubating cells with recombinant HSP70 also decreased viral infectivity. Knockdown and inhibition of HSP70 also significantly diminished viral production. These results implicate HSP70 in the pathogenesis of ZIKV and identify HSP70 as a potential host therapeutic target against ZIKV infection.

Proteínas de Choque Térmico HSP70/isolamento & purificação , Interações Hospedeiro-Patógeno , Vírion/isolamento & purificação , Zika virus/isolamento & purificação , Animais , Linhagem Celular , Centrifugação com Gradiente de Concentração , Cromatografia em Gel , Humanos , Espectrometria de Massas
Int J Antimicrob Agents ; 47(4): 289-96, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27013001


The human molecular chaperones heat shock protein 70 (Hsp70) and heat shock cognate protein 70 (Hsc70) bind to the hepatitis C viral nonstructural protein 5A (NS5A) and regulate its activity. Specifically, Hsp70 is involved in NS5A-augmented internal ribosomal entry site (IRES)-mediated translation of the viral genome, whilst Hsc70 appears to be primarily important for intracellular infectious virion assembly. To better understand the importance of these two chaperones in the viral life cycle, infected human cells were treated with allosteric Hsp70/Hsc70 inhibitors (AHIs). Treatment with AHIs significantly reduced the production of intracellular virus at concentrations that were non-toxic to human hepatoma Huh7.5 cells. The supernatant of treated cultures was then used to infect naïve cells, revealing that AHIs also lowered levels of secreted virus. In contrast to their effects on virion assembly, AHIs did not impact the stability of NS5A or viral protein translation in IRES assays. These results suggest that Hsc70 plays a particularly important and sensitive role in virion assembly. Indeed, it was found that combination of AHIs with a peptide-based viral translation inhibitor exhibited additive antiviral activity. Together these results suggest that the host Hsc70 is a new antiviral target and that its inhibitors utilise a new mechanism of action.

Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Hepacivirus/efeitos dos fármacos , Hepacivirus/fisiologia , Montagem de Vírus/efeitos dos fármacos , Antivirais/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/toxicidade , Proteínas de Choque Térmico HSC70/antagonistas & inibidores , Proteínas de Choque Térmico HSC70/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/fisiologia , Hepatócitos/virologia , Humanos