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1.
Acad Radiol ; 30(8): 1521-1527, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37002035

RESUMO

RATIONALE AND OBJECTIVES: The reproducibility of imaging models for predicting microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC) remains questionable due to inconsistent interpretation of image signs. Our aim was to screen for high-consensus MRI features to develop a repeatable model for predicting MVI. MATERIALS AND METHODS: We included 219 patients with HCC who underwent surgical resection, and patients were divided into a training cohort (n = 145) and a validation cohort (n = 74). Morphological characteristics, signal features on hepatobiliary phases, and dynamic enhancement patterns were qualitatively interobserver evaluated. Interobserver agreement was assessed using Cohen's κ for selecting features with high interobserver agreement. Risk factors that were significant in stepwise multivariate analysis and that could be measured with good interobserver agreement were used to construct a predictive model, which was assessed in the validation cohort. The diagnostic performance of the model was evaluated based on area under the receiver operating characteristic curve (AUC). RESULTS: Multivariate analysis identified nonsmooth tumor margin, absence of radiologic capsule, and intratumoral artery as independent risk factors of MVI. These MRI-based features showed good or nearly perfect interobserver agreement between radiologists (κ > 0.6). The predictive model predicted MVI well in the training (AUC 0.734) and validation cohorts (AUC 0.759) and fitted well to calibration curves. CONCLUSION: MRI features included nonsmooth tumor margin, absence of radiologic capsule, and intratumoral artery that can be assessed with high interobserver agreement can predict MVI in HCC patients. The predictive model described here may be useful to radiologists, regardless of experience level.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Invasividade Neoplásica/diagnóstico por imagem , Reprodutibilidade dos Testes
2.
Front Neuroanat ; 16: 995369, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466782

RESUMO

Glaucoma is a leading cause of blindness with progressive degeneration of retinal ganglion cells. Aging and increased intraocular pressure (IOP) are major risk factors. Lowering IOP does not always stop the disease progression. Alternative ways of protecting the optic nerve are intensively studied in glaucoma. Astrocytes are macroglia residing in the retina, optic nerve head (ONH), and visual brain, which keep neuronal homeostasis, regulate neuronal activities and are part of the immune responses to the retina and brain insults. In this brief review, we discuss the activation and heterogeneity of astrocytes in the retina, optic nerve head, and visual brain of glaucoma patients and animal models. We also discuss some recent transgenic and gene knockout studies using glaucoma mouse models to clarify the role of astrocytes in the pathogenesis of glaucoma. Astrocytes are heterogeneous and play crucial roles in the pathogenesis of glaucoma, especially in the process of neuroinflammation and mitochondrial dysfunction. In astrocytes, overexpression of Stat3 or knockdown of IκKß/p65, caspase-8, and mitochondrial uncoupling proteins (Ucp2) can reduce ganglion cell loss in glaucoma mouse models. Based on these studies, therapeutic strategies targeting the heterogeneity of reactive astrocytes by enhancing their beneficial reactivity or suppressing their detrimental reactivity are alternative options for glaucoma treatment in the future.

3.
Exp Eye Res ; 210: 108701, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34252413

RESUMO

Retinitis pigmentosa (RP) is a major cause of inherited blindness, and there is presently no cure for RP. Rd1 mouse is the most commonly used RP animal model. Re-expression of cell cycle proteins in post-mitotic neurons is considered an important mechanism of neurodegenerative diseases, including RP. The retinoblastoma tumor suppressor (Rb) is a major regulator of cell cycle progression, yet its role in rd1 mouse retina and related signaling pathways have never been analyzed. By crossing α-Cre, Rbf/f mice with rd1 mice, p21cip1-/- mice, Cdk1f/f mice and Cdk2f/f mice, we established multiple rd1 mouse models with deletions of Rb gene, Cdkn1a (p21cip1) gene, Cdk1 and Cdk2 gene in the retina. Cdk inhibitor CR8 was injected into the vitreous of rd1 mouse to investigate its effects on photoreceptor survival. Rb gene knockout (KO) induces cell death in excitatory retinal neurons (rods, rod bipolar and ganglions) and ectopic proliferation of retinal cells; but it paradoxically delays the rod death of rd1 mice, which is primarily mediated by the Cdk inhibitor Cdkn1a (p21cip1). Interestingly, p21cip1 protects the ectopic dividing rd1 rod cells by inhibiting Cdk1 and Cdk2. However, inhibiting Cdk1 and Cdk2 in rd1 mice with non-dividing rods only has limited and transient protective effects. Our data suggest that there is no ectopic division of rd1 rod cells, and RbKO induces ectopic division but delays the death of rd1 rod cells. This reveals the important protective role of Rb-p21cip1-Cdk axis in rd1 rod cells. P21cip1 is a potential target for future therapy of RP.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/fisiologia , Degeneração Retiniana/prevenção & controle , Proteína do Retinoblastoma/deficiência , Animais , Apoptose , Proteína Quinase CDC2/metabolismo , Sobrevivência Celular/fisiologia , Quinase 2 Dependente de Ciclina/metabolismo , Eletrorretinografia , Inibidores Enzimáticos/farmacologia , Marcação In Situ das Extremidades Cortadas , Injeções Intravítreas , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Microscopia de Fluorescência , Purinas/farmacologia , Piridinas/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Células Fotorreceptoras Retinianas Bastonetes/efeitos dos fármacos , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/patologia
4.
Front Cell Infect Microbiol ; 11: 739707, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35004341

RESUMO

Graves' disease (GD) is a clinical syndrome with an enlarged and overactive thyroid gland, an accelerated heart rate, Graves' orbitopathy (GO), and pretibial myxedema (PTM). GO is the most common extrathyroidal complication of GD. GD/GO has a significant negative impact on the quality of life. GD is the most common systemic autoimmune disorder, mediated by autoantibodies to the thyroid-stimulating hormone receptor (TSHR). It is generally accepted that GD/GO results from complex interactions between genetic and environmental factors that lead to the loss of immune tolerance to thyroid antigens. However, the exact mechanism is still elusive. Systematic investigations into GD/GO animal models and clinical patients have provided important new insight into these disorders during the past 4 years. These studies suggested that gut microbiota may play an essential role in the pathogenesis of GD/GO. Antibiotic vancomycin can reduce disease severity, but fecal material transfer (FMT) from GD/GO patients exaggerates the disease in GD/GO mouse models. There are significant differences in microbiota composition between GD/GO patients and healthy controls. Lactobacillus, Prevotella, and Veillonella often increase in GD patients. The commonly used therapeutic agents for GD/GO can also affect the gut microbiota. Antigenic mimicry and the imbalance of T helper 17 cells (Th17)/regulatory T cells (Tregs) are the primary mechanisms proposed for dysbiosis in GD/GO. Interventions including antibiotics, probiotics, and diet modification that modulate the gut microbiota have been actively investigated in preclinical models and, to some extent, in clinical settings, such as probiotics (Bifidobacterium longum) and selenium supplements. Future studies will reveal molecular pathways linking gut and thyroid functions and how they impact orbital autoimmunity. Microbiota-targeting therapeutics will likely be an essential strategy in managing GD/GO in the coming years.


Assuntos
Microbioma Gastrointestinal , Doença de Graves , Oftalmopatia de Graves , Animais , Humanos , Camundongos , Qualidade de Vida , Receptores da Tireotropina
5.
JCI Insight ; 4(22)2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31613797

RESUMO

Von Hippel-Lindau (Vhl) protein inhibits hypoxia-inducible factor (Hif), yet its deletion in murine retina does not cause the extensive angiogenesis expected with Hif induction. The mechanism is unclear. Here we show that retinoblastoma tumor suppressor (Rb1) constrains expression of Hif target genes in the Vhl-/- retina. Deleting Rb1 induced extensive retinal neovascularization and autophagic ablation of photoreceptors in the Vhl-/- retina. RNA-sequencing, ChIP, and reporter assays showed Rb1 recruitment to and repression of certain Hif target genes. Activating Rb1 by deleting cyclin D1 induced a partial defect in the retinal superficial vascular plexus. Unexpectedly, removing Vhl suppressed retinoblastoma formation in murine Rb1/Rbl1-deficient retina but generated subretinal vascular growths resembling retinal angiomatous proliferation (RAP) and retinal capillary hemangioblastoma (RCH). Most stromal cells in the RAP/RCH-like lesions were Sox9+, suggesting a Müller glia origin, and expressed Lgals3, a marker of human brain hemangioblastoma. Thus, the Rb family limit Hif target gene expression in the Vhl-/- retina, and removing this inhibitory signal generates new models for RAP and RCH.


Assuntos
Hemangioblastoma , Neovascularização Retiniana , Proteínas de Ligação a Retinoblastoma , Proteína p107 Retinoblastoma-Like , Proteína Supressora de Tumor Von Hippel-Lindau , Animais , Proliferação de Células/genética , Hemangioblastoma/genética , Hemangioblastoma/metabolismo , Camundongos , Camundongos Knockout , Neovascularização Retiniana/genética , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia , Proteínas de Ligação a Retinoblastoma/genética , Proteínas de Ligação a Retinoblastoma/metabolismo , Proteína p107 Retinoblastoma-Like/genética , Proteína p107 Retinoblastoma-Like/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo
6.
Medicine (Baltimore) ; 94(39): e1105, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26426603

RESUMO

Incidence of esophageal adenocarcinoma (EAC) has risen rapidly over the past decades in Western countries. As a premalignant lesion, Barrett's esophagus (BE) is an established risk factor of EAC. This study estimated the impact of surveillance endoscopy for BE on population's survival upon EAC by a whole-population cost-effectiveness analysis among modeled Western population. Possibilities and survival payoffs were retrieved through literature searching based on PubMed database. Patients with BE were classified as adequate surveillance (AS), inadequate surveillance (IAS), and no surveillance groups. Direct cost of endoscopy per person-year was estimated from diagnosis of BE to before diagnosis of EAC in the whole-population model, whereas the payoff was 2-year disease-specific survival rate of EAC. AS for patients with BE had lower cost-effectiveness ratio (CER) than that of IAS group, as well as lower incremental cost-effectiveness ratio (6116 ∈/% vs 118,347 ∈/%). Prolonging the surveillance years could decrease the yearly cost in whole population and also relevant CERs, despite increased total cost. Increasing the proportion of participants in AS group could improve the survival benefit. The maximal payoff was up to 2-year mortality reduction of 2.7 per 100,000 persons by spending extra ∈ 1,658,913 per 100,000 person-years. A longer endoscopic surveillance among BE subpopulation plan can reduce yearly budget. Attempt to increase the proportion of AS participants can induce decline in population mortality of EAC, despite extra but acceptable expenditure. However, regarding optimal cost-effectiveness, further studies are still required to identify a high-risk subpopulation out of BE patients for endoscopic surveillance.


Assuntos
Adenocarcinoma/diagnóstico , Esôfago de Barrett/complicações , Neoplasias Esofágicas/diagnóstico , Esofagoscopia/economia , Adenocarcinoma/etiologia , Análise Custo-Benefício , Neoplasias Esofágicas/etiologia , Humanos , Vigilância da População
7.
Medicine (Baltimore) ; 94(31): e1292, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26252305

RESUMO

A prospective randomized, controlled, single-blinded trial to compare the effectiveness and safety of heparin saline (HS) to those of normal saline (NS) as flushing and locking solutions for peripheral venous catheter (PVC) in decompensated liver cirrhosis (DLC) patients.Patients with DLC at our institution between April 2012 and March 2013 were enrolled after obtaining informed consent. The patients were randomly allocated into 2 groups: the NS group received preservative-free 0.9% sodium chloride as the flushing and locking solution, while the HS group received HS (50 U/mL). PVC-related events and the duration of PVC maintenance were compared between the 2 groups. Moreover, the preinfusion and postinfusion levels of prothrombin time (PT), activated partial thromboplastin time (APTT), and platelet (PLT) were also compared.A total of 32 and 36 DLC patients in the NS (125 PVCs) and HS (65 PVCs) groups, respectively, were analyzed. Baseline characteristics, including gender, age, Child-Pugh grade, PVC type and administration of anticoagulant, and irritant agents, were comparable between the 2 groups (P > 0.05). The maintenance times of the HS and NS groups were 80.27 ±â€Š26.47 and 84.19 ±â€Š29.32 hours, respectively (P = 0.397). Removal of PVC for abnormal reasons occurred in 30.7% and 22.4% of patients in the HS and NS groups (P = 0.208). The PVC occlusion rates were 6.2% and 5.6% in the HS and NS groups, respectively (OR = 1.11, 95% CI 0.31-3.92). The PT, APTT, and PLT levels were comparable between the 2 groups both before and after infusion (P > 0.05). Incremental analyses showed that Child-Pugh grade C might be a risk factor for the suppression of PLT in the HS group.We consider NS to be as effective as and safer than conventional HS for flushing and locking PVC in decompensated liver cirrhosis patients.


Assuntos
Anticoagulantes/uso terapêutico , Cateterismo Periférico/efeitos adversos , Oclusão de Enxerto Vascular/prevenção & controle , Heparina/uso terapêutico , Cirrose Hepática/terapia , Cloreto de Sódio/uso terapêutico , Adulto , Feminino , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Estudos Prospectivos , Tempo de Protrombina , Método Simples-Cego , Resultado do Tratamento
8.
Nanoscale ; 6(8): 4063-6, 2014 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-24603873

RESUMO

Plate-like heterogeneous NiO/WO3 nanocomposites have been successfully prepared by annealing Ni(OH)2 and H2WO4 in air. These NiO/WO3 nanocomposites have shown excellent sensitivity towards NO2 and ultrafast response at room temperature due to their p-n heterogeneous characteristics.


Assuntos
Nanocompostos/química , Níquel/química , Dióxido de Nitrogênio/análise , Óxidos/química , Tungstênio/química , Temperatura Alta
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