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1.
Radiology ; 310(2): e232365, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38349244

RESUMO

Background Image-guided tumor ablation is the first-line therapy for early-stage hepatocellular carcinoma (HCC), with ongoing investigations into its combination with immunotherapies. Matrix metalloproteinase (MMP) inhibition demonstrates immunomodulatory potential and reduces HCC tumor growth when combined with ablative treatment. Purpose To evaluate the effect of incomplete cryoablation with or without MMP inhibition on the local immune response in residual tumors in a murine HCC model. Materials and Methods Sixty 8- to 10-week-old female BALB/c mice underwent HCC induction with use of orthotopic implantation of syngeneic Tib-75 cells. After 7 days, mice with a single lesion were randomized into treatment groups: (a) no treatment, (b) MMP inhibitor, (c) incomplete cryoablation, and (d) incomplete cryoablation and MMP inhibitor. Macrophage and T-cell subsets were assessed in tissue samples with use of immunohistochemistry and immunofluorescence (cell averages calculated using five 1-µm2 fields of view [FOVs]). C-X-C motif chemokine receptor type 3 (CXCR3)- and interferon γ (IFNγ)-positive T cells were assessed using flow cytometry. Groups were compared using unpaired Student t tests, one-way analysis of variance with Tukey correction, and the Kruskal-Wallis test with Dunn correction. Results Mice treated with incomplete cryoablation (n = 6) showed greater infiltration of CD206+ tumor-associated macrophages (mean, 1.52 cells per FOV vs 0.64 cells per FOV; P = .03) and MMP9-expressing cells (mean, 0.89 cells per FOV vs 0.11 cells per FOV; P = .03) compared with untreated controls (n = 6). Incomplete cryoablation with MMP inhibition (n = 6) versus without (n = 6) led to greater CD8+ T-cell (mean, 15.8% vs 8.29%; P = .04), CXCR3+CD8+ T-cell (mean, 11.64% vs 8.47%; P = .004), and IFNγ+CD8+ T-cell infiltration (mean, 11.58% vs 5.18%; P = .02). Conclusion In a mouse model of HCC, incomplete cryoablation and systemic MMP inhibition showed increased cytotoxic CD8+ T-cell infiltration into the residual tumor compared with either treatment alone. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Gemmete in this issue.


Assuntos
Carcinoma Hepatocelular , Criocirurgia , Neoplasias Hepáticas , Feminino , Animais , Camundongos , Carcinoma Hepatocelular/cirurgia , Inibidores de Metaloproteinases de Matriz , Neoplasias Hepáticas/cirurgia , Linfócitos T CD8-Positivos , Metaloproteinases da Matriz
2.
NMR Biomed ; 37(5): e5102, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38263680

RESUMO

A unique feature of the tumor microenvironment is extracellular acidosis in relation to intracellular milieu. Metabolic reprogramming in tumors results in overproduction of H+ ions (and lactate), which are extruded from the cells to support tumor survival and progression. As a result, the transmembrane pH gradient (ΔpH), representing the difference between intracellular pH (pHi) and extracellular pH (pHe), is posited to be larger in tumors compared with normal tissue. Controlling the transmembrane pH difference has promise as a potential therapeutic target in cancer as it plays an important role in regulating drug delivery into cells. The current study shows successful development of an MRI/MRSI-based technique that provides ΔpH imaging at submillimeter resolution. We applied this technique to image ΔpH in rat brains with RG2 and U87 gliomas, as well as in mouse brains with GL261 gliomas. pHi was measured with Amine and Amide Concentration-Independent Detection (AACID), while pHe was measured with Biosensor Imaging of Redundant Deviation in Shifts (BIRDS). The results indicate that pHi was slightly higher in tumors (7.40-7.43 in rats, 7.39-7.47 in mice) compared with normal brain (7.30-7.38 in rats, 7.32-7.36 in mice), while pHe was significantly lower in tumors (6.62-6.76 in rats, 6.74-6.84 in mice) compared with normal tissue (7.17-7.22 in rats, 7.20-7.21 in mice). As a result, ΔpH was higher in tumors (0.64-0.81 in rats, 0.62-0.65 in mice) compared with normal brain (0.13-0.16 in rats, 0.13-0.16 in mice). This work establishes an MRI/MRSI-based platform for ΔpH imaging at submillimeter resolution in gliomas.


Assuntos
Neoplasias Encefálicas , Glioma , Ratos , Camundongos , Animais , Força Próton-Motriz , Neoplasias Encefálicas/metabolismo , Roedores , Glioma/diagnóstico por imagem , Encéfalo/metabolismo , Imageamento por Ressonância Magnética/métodos , Concentração de Íons de Hidrogênio , Microambiente Tumoral
3.
J Vasc Interv Radiol ; 34(3): 404-408.e1, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36473611

RESUMO

Liver cirrhosis is a major underlying factor in the development of hepatocellular carcinoma. Currently, there is an unmet need for midsize experimental vertebrate models that would offer reproducible implantable liver tumors in a cirrhotic liver background. This study establishes a protocol for a syngeneic rabbit model of VX2 liver cancer with underlying liver cirrhosis induced using carbon tetrachloride (CCl4). Male New Zealand white rabbits (n = 3) received CCl4 by intragastric administration once weekly. Concentrations started at 5% v/v CCl4 dissolved in olive oil. CCl4 dosing was progressively increased every week by 2.5% v/v increments for the duration of treatment (16 weeks total). VX2 tumors were then orthotopically implanted into the left hepatic lobe and allowed to grow for 3 weeks. Cross-sectional imaging confirmed the presence of hepatic tumors. Gross and histopathological evaluations showed reproducible tumor growth in the presence of liver cirrhosis in all animals.


Assuntos
Carcinoma Hepatocelular , Cirrose Hepática Experimental , Neoplasias Hepáticas Experimentais , Neoplasias Hepáticas , Coelhos , Masculino , Animais , Tetracloreto de Carbono/efeitos adversos , Fígado/patologia , Cirrose Hepática , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas Experimentais/patologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/patologia
4.
J Vasc Interv Radiol ; 34(12): 2162-2172.e2, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37634850

RESUMO

PURPOSE: To compare the mechanistic effects and hypertrophy outcomes using 2 different portal vein embolization (PVE) regimens in normal and cirrhotic livers in a large animal model. METHODS AND MATERIALS: The Institutional Animal Care and Use Committee approved all experiments conducted in this study. Fourteen female Yorkshire pigs were separated into a cirrhotic group (CG, n = 7) and non-cirrhotic group (NCG, n = 7) and further subgrouped into those using microspheres and coils (MC, n = 3) or n-butyl cyanoacrylate (nBCA, n = 3) and their corresponding controls (each n = 1). A 3:1 ethiodized oil and ethanol mixture was administered intra-arterially in the CG to induce cirrhosis 4 weeks before PVE. Animals underwent baseline computed tomography (CT), PVE including pre-PVE and post-PVE pressure measurements, and CT imaging at 2 and 4 weeks after PVE. Immunofluorescence stainings for CD3, CD16, Ki-67, and caspase 3 were performed to assess immune cell infiltration, hepatocyte proliferation, and apoptosis. Statistical significance was tested using the Student's t test. RESULTS: Four weeks after PVE, the percentage of future liver remnant (FLR%) increased by 18.8% (standard deviation [SD], 3.6%) vs 10.9% (SD, 0.95%; P < .01) in the NCG vs CG. The baseline percentage of standardized future liver remnant (sFLR%) for the controls were 41.6% for CG vs 43.6% for NCG. Based on the embolic agents used, the sFLR% two weeks after PVE was 58.4% (SD, 3.7%) and 52.2% (SD, 0.9%) (P < .01) for MC and 46.0% (SD, 2.2%) and 47.2% (SD, 0.4%) for nBCA in the NCG and CG, respectively. Meanwhile, the sFLR% 4 weeks after PVE was 60.5% (SD, 3.9%) and 54.9% (SD, 0.8%) (P < .01) and 60.4% (SD, 3.5%) and 54.2% (SD, 0.95%) (P < .01), respectively. Ki-67 signal intensity increased in the embolized lobe in both CG and NCG (P < .01). CONCLUSIONS: This preclinical study demonstrated that MC could be the preferred embolic of choice compared to nBCA when a substantial and rapid FLR increase is needed for resection, in both cirrhotic and non-cirrhotic livers.


Assuntos
Embolia , Embolização Terapêutica , Neoplasias Hepáticas , Animais , Feminino , Suínos , Veia Porta/diagnóstico por imagem , Veia Porta/patologia , Antígeno Ki-67 , Fígado/patologia , Hepatectomia/métodos , Embolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Hipertrofia/patologia , Hipertrofia/cirurgia , Embolia/cirurgia , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Modelos Animais , Resultado do Tratamento
5.
J Vasc Interv Radiol ; 34(3): 395-403.e5, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36423815

RESUMO

PURPOSE: To establish molecular magnetic resonance (MR) imaging instruments for in vivo characterization of the immune response to hepatic radiofrequency (RF) ablation using cell-specific immunoprobes. MATERIALS AND METHODS: Seventy-two C57BL/6 wild-type mice underwent standardized hepatic RF ablation (70 °C for 5 minutes) to generate a coagulation area measuring 6-7 mm in diameter. CD68+ macrophage periablational infiltration was characterized with immunohistochemistry 24 hours, 72 hours, 7 days, and 14 days after ablation (n = 24). Twenty-one mice were subjected to a dose-escalation study with either 10, 15, 30, or 60 mg/kg of rhodamine-labeled superparamagnetic iron oxide nanoparticles (SPIONs) or 2.4, 1.2, or 0.6 mg/kg of gadolinium-160 (160Gd)-labeled CD68 antibody for assessment of the optimal in vivo dose of contrast agent. MR imaging experiments included 9 mice, each receiving 10-mg/kg SPIONs to visualize phagocytes using T2∗-weighted imaging in a horizontal-bore 9.4-T MR imaging scanner, 160Gd-CD68 for T1-weighted MR imaging of macrophages, or 0.1-mmol/kg intravenous gadoterate (control group). Radiological-pathological correlation included Prussian blue staining, rhodamine immunofluorescence, imaging mass cytometry, and immunohistochemistry. RESULTS: RF ablation-induced periablational infiltration (206.92 µm ± 12.2) of CD68+ macrophages peaked at 7 days after ablation (P < .01) compared with the untreated lobe. T2∗-weighted MR imaging with SPION contrast demonstrated curvilinear T2∗ signal in the transitional zone (TZ) (186 µm ± 16.9), corresponsing to Iron Prussian blue staining. T1-weighted MR imaging with 160Gd-CD68 antibody showed curvilinear signal in the TZ (164 µm ± 3.6) corresponding to imaging mass cytometry. CONCLUSIONS: Both SPION-enhanced T2∗-weighted and 160Gd-enhanced T1-weighted MR imaging allow for in vivo monitoring of macrophages after RF ablation, demonstrating the feasibility of this model to investigate local immune responses.


Assuntos
Fígado , Ablação por Radiofrequência , Animais , Camundongos , Camundongos Endogâmicos C57BL , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Macrófagos , Imunidade , Meios de Contraste
6.
Eur Radiol ; 32(4): 2437-2447, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34718844

RESUMO

OBJECTIVES: The goal of this study was to investigate the effects of TACE using Lipiodol, Oncozene™ drug-eluting embolics (DEEs), or LUMI™-DEEs alone, or combined with bicarbonate on the metabolic and immunological tumor microenvironment in a rabbit VX2 tumor model. METHODS: VX2 liver tumor-bearing rabbits were assigned to five groups. MRI and extracellular pH (pHe) mapping using Biosensor Imaging of Redundant Deviation in Shifts (BIRDS) were performed before and after intra-arterial therapy with conventional TACE (cTACE), DEE-TACE with Idarubicin-eluting Oncozene™-DEEs, or Doxorubicin-eluting LUMI™-DEEs, each with or without prior bicarbonate infusion, and in untreated rabbits or treated with intra-arterial bicarbonate only. Imaging results were validated with immunohistochemistry (IHC) staining of cell viability (PCNA, TUNEL) and immune response (HLA-DR, CD3). Statistical analysis was performed using Mann-Whitney U test. RESULTS: pHe mapping revealed that combining cTACE with prior bicarbonate infusion significantly increased tumor pHe compared to control (p = 0.0175) and cTACE alone (p = 0.0025). IHC staining revealed peritumoral accumulation of HLA-DR+ antigen-presenting cells and CD3 + T-lymphocytes in controls. cTACE-treated tumors showed reduced immune infiltration, which was restored through combination with bicarbonate. DEE-TACE with Oncozene™-DEEs induced moderate intratumoral and marked peritumoral infiltration, which was slightly reduced with bicarbonate. Addition of bicarbonate prior to LUMI™-beads enhanced peritumoral immune cell infiltration compared to LUMI™-beads alone and resulted in the strongest intratumoral immune cell infiltration across all treated groups. CONCLUSIONS: The choice of chemoembolic regimen for TACE strongly affects post-treatment TME pHe and the ability of immune cells to accumulate and infiltrate the tumor tissue. KEY POINTS: • Combining conventional transarterial chemotherapy with prior bicarbonate infusion increases the pHe towards a more physiological value (p = 0.0025). • Peritumoral infiltration and intratumoral accumulation patterns of antigen-presenting cells and T-lymphocytes after transarterial chemotherapy were dependent on the choice of the chemoembolic regimen. • Combination of intra-arterial treatment with Doxorubicin-eluting LUMI™-beads and bicarbonate infusion resulted in the strongest intratumoral presence of immune cells (positivity index of 0.47 for HLADR+-cells and 0.62 for CD3+-cells).


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica/métodos , Doxorrubicina , Óleo Etiodado , Neoplasias Hepáticas/patologia , Coelhos , Microambiente Tumoral
7.
J Vasc Interv Radiol ; 33(3): 324-332.e2, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34923098

RESUMO

PURPOSE: To show that a deep learning (DL)-based, automated model for Lipiodol (Guerbet Pharmaceuticals, Paris, France) segmentation on cone-beam computed tomography (CT) after conventional transarterial chemoembolization performs closer to the "ground truth segmentation" than a conventional thresholding-based model. MATERIALS AND METHODS: This post hoc analysis included 36 patients with a diagnosis of hepatocellular carcinoma or other solid liver tumors who underwent conventional transarterial chemoembolization with an intraprocedural cone-beam CT. Semiautomatic segmentation of Lipiodol was obtained. Subsequently, a convolutional U-net model was used to output a binary mask that predicted Lipiodol deposition. A threshold value of signal intensity on cone-beam CT was used to obtain a Lipiodol mask for comparison. The dice similarity coefficient (DSC), mean squared error (MSE), center of mass (CM), and fractional volume ratios for both masks were obtained by comparing them to the ground truth (radiologist-segmented Lipiodol deposits) to obtain accuracy metrics for the 2 masks. These results were used to compare the model versus the threshold technique. RESULTS: For all metrics, the U-net outperformed the threshold technique: DSC (0.65 ± 0.17 vs 0.45 ± 0.22, P < .001) and MSE (125.53 ± 107.36 vs 185.98 ± 93.82, P = .005). The difference between the CM predicted and the actual CM was 15.31 mm ± 14.63 versus 31.34 mm ± 30.24 (P < .001), with lesser distance indicating higher accuracy. The fraction of volume present ([predicted Lipiodol volume]/[ground truth Lipiodol volume]) was 1.22 ± 0.84 versus 2.58 ± 3.52 (P = .048) for the current model's prediction and threshold technique, respectively. CONCLUSIONS: This study showed that a DL framework could detect Lipiodol in cone-beam CT imaging and was capable of outperforming the conventionally used thresholding technique over several metrics. Further optimization will allow for more accurate, quantitative predictions of Lipiodol depositions intraprocedurally.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Aprendizado Profundo , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Óleo Etiodado , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia
8.
J Vasc Interv Radiol ; 33(7): 764-774.e4, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35346859

RESUMO

PURPOSE: To characterize the effects of commonly used transcatheter arterial chemoembolization (TACE) regimens on the immune response and immune checkpoint marker expression using a VX2 rabbit liver tumor model. MATERIALS AND METHODS: Twenty-four VX2 liver tumor-bearing New Zealand white rabbits were assigned to 7 groups (n = 3 per group) undergoing locoregional therapy as follows: (a) bicarbonate infusion without embolization, (b) conventional TACE (cTACE) using a water-in-oil emulsion containing doxorubicin mixed 1:2 with Lipiodol, drug-eluting embolic-TACE with either (c) idarubicin-eluting Oncozene microspheres (40 µm) or (d) doxorubicin-eluting Lumi beads (40-90 µm). For each therapy arm (b-d), a tandem set of 3 animals with additional bicarbonate infusion before TACE was added, to evaluate the effect of pH modification on the immune response. Three untreated rabbits served as controls. Tissue was harvested 24 hours after treatment, followed by digital immunohistochemistry quantification (counts/µm2 ± SEM) of tumor-infiltrating cluster of differentiation 3+ T-lymphocytes, human leukocyte antigen DR type antigen-presenting cells (APCs), cytotoxic T-lymphocyte-associated protein-4 (CTLA-4), and programmed cell death protein-1 (PD-1)/PD-1 ligand (PD-L1) pathway axis expression. RESULTS: Lumi-bead TACE induced significantly more intratumoral T-cell and APC infiltration than cTACE and Oncozene-microsphere TACE. Additionally, tumors treated with Lumi-bead TACE expressed significantly higher intratumoral immune checkpoint markers compared with cTACE and Oncozene-microsphere TACE. Neoadjuvant bicarbonate demonstrated the most pronounced effect on cTACE and resulted in a significant increase in intratumoral cluster of differentiation 3+ T-cell infiltration compared with cTACE alone. CONCLUSIONS: This preclinical study revealed significant differences in evoked tumor immunogenicity depending on the choice of chemoembolic regimen for TACE.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Animais , Antibióticos Antineoplásicos , Bicarbonatos/uso terapêutico , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Doxorrubicina , Neoplasias Hepáticas/terapia , Receptor de Morte Celular Programada 1 , Coelhos
9.
Adv Exp Med Biol ; 1353: 217-224, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35137376

RESUMO

OBJECTIVE: The objective of this systematic review was to analyze the main morphofunctional changes in the involvement of multiple organs in patients infected with SARS-CoV-2, correlating anatomopathological findings with the clinical picture. METHODS: The present study selected articles through electronic search of indexed journals in the PubMed and SciVerse Scopus databases, from December 2019 to May 2020, using the keywords "autopsy," "pathogenicity," and "COVID-19." Two hundred nine articles were identified, and the full texts of 18 articles were reviewed, 5 of them being selected for this review. RESULTS: The ACE2 receptor plays a role in introducing viral material into the cell, having high expression in type II alveoli. Histopathological analyzes of the lungs of patients with COVID-19 show that SARS-CoV-2 produces, in this organ, in addition to an inflammatory process, a diffuse alveolar damage (DAD), which can cause acute respiratory distress syndrome (ARDS). Macroscopically, the lungs become heavier, firmer, and redder. The clinical features of these patients are variable; the most common are respiratory symptoms associated with fever, myalgia, or fatigue. CONCLUSION: The observations points to the consensus that the lungs are the main targets of COVID-19, with morphological and functional changes of interest, including important sequels, and presenting diffuse alveolar damage as a substrate for an unfavorable outcome with ARDS. Changes in micro and macroscopic levels corroborate to the clinical progression of the disease and that these alterations are not specific, which ratify, in addition to the anatomopathological examination, a need to use the association of clinical and epidemiological data for diagnostic confirmation.


Assuntos
COVID-19 , Síndrome do Desconforto Respiratório , Humanos , Pulmão , Alvéolos Pulmonares , SARS-CoV-2
10.
Adv Exp Med Biol ; 1352: 45-71, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35132594

RESUMO

Despite the recent announcement of the new pathogenic coronavirus to man, SARS-CoV2, a large number of publications are presented to the scientific community. An organized and systematic review of the epidemiological, etiological, and pathogenic factors of COVID-19 is presented. This is a systematic review using the databases MEDLINE, EMBASE, Web of Science, SCIELO; the descriptors coronavirus, SARS-CoV-2, etiology, epidemiology, pathophysiology, pathogenesis, COVID-19, with publications from December 2019 to January 2021, resulting in more than 800 publications and 210 selected. The data suggest that COVID-19 is associated with SAR-CoV-2 infection, with the transmission of contagion by fomites, salivary droplets, and other forms, such as vertical and fecal-oral. The bat and other vertebrates appear to be reservoirs and part of the transmission chain. The virus uses cell receptors to infect human cells, especially ACE2, like other coronaviruses. Heat shock proteins have different roles in the infection, sometimes facilitating it, sometimes participating in more severe conditions, when not serving as a therapeutic target. The available data allow us to conclude that COVID-19 is a pandemic viral disease, behaving as a challenge for public health worldwide, determining aggressive conditions with a high mortality rate in patients with risk factors, without treatment, but with the recent availability of the first vaccines.


Assuntos
COVID-19 , Animais , Humanos , Masculino , Pandemias , RNA Viral , SARS-CoV-2
11.
Radiology ; 296(3): 575-583, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32633675

RESUMO

Background The immuno-metabolic interplay has gained interest for determining and targeting immunosuppressive tumor micro-environments that remain a barrier to current immuno-oncologic therapies in hepatocellular carcinoma. Purpose To develop molecular MRI tools to reveal resistance mechanisms to immuno-oncologic therapies caused by the immuno-metabolic interplay in a translational liver cancer model. Materials and Methods A total of 21 VX2 liver tumor-bearing New Zealand white rabbits were used between October 2018 and February 2020. Rabbits were divided into three groups. Group A (n = 3) underwent intra-arterial infusion of gadolinium 160 (160Gd)-labeled anti-human leukocyte antigen-DR isotope (HLA-DR) antibodies to detect antigen-presenting immune cells. Group B (n = 3) received rhodamine-conjugated superparamagnetic iron oxide nanoparticles (SPIONs) intravenously to detect macrophages. These six rabbits underwent 3-T MRI, including T1- and T2-weighted imaging, before and 24 hours after contrast material administration. Group C (n = 15) underwent extracellular pH mapping with use of MR spectroscopy. Of those 15 rabbits, six underwent conventional transarterial chemoembolization (TACE), four underwent conventional TACE with extracellular pH-buffering bicarbonate, and five served as untreated controls. MRI signal intensity distribution was validated by using immunohistochemistry staining of HLA-DR and CD11b, Prussian blue iron staining, fluorescence microscopy of rhodamine, and imaging mass cytometry (IMC) of gadolinium. Statistical analysis included Mann-Whitney U and Kruskal-Wallis tests. Results T1-weighted MRI with 160Gd-labeled antibodies revealed localized peritumoral ring enhancement, which corresponded to gadolinium distribution detected with IMC. T2-weighted MRI with SPIONs showed curvilinear signal intensity representing selective peritumoral deposition in macrophages. Extracellular pH-specific MR spectroscopy of untreated liver tumors showed acidosis (mean extracellular pH, 6.78 ± 0.09) compared with liver parenchyma (mean extracellular pH, 7.18 ± 0.03) (P = .008) and peritumoral immune cell exclusion. Normalization of tumor extracellular pH (mean, 6.96 ± 0.05; P = .02) using bicarbonate during TACE increased peri- and intratumoral immune cell infiltration (P = .002). Conclusion MRI in a rabbit liver tumor model was used to visualize resistance mechanisms mediated by the immuno-metabolic interplay that inform susceptibility and response to immuno-oncologic therapies, providing a therapeutic strategy to restore immune permissiveness in liver cancer. © RSNA, 2020 Online supplemental material is available for this article.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas Experimentais , Imageamento por Ressonância Magnética/métodos , Imagem Molecular/métodos , Animais , Anticorpos/administração & dosagem , Anticorpos/química , Anticorpos/metabolismo , Biomarcadores , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Meios de Contraste/administração & dosagem , Meios de Contraste/química , Meios de Contraste/farmacocinética , Gadolínio/administração & dosagem , Gadolínio/química , Gadolínio/farmacocinética , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Neoplasias Hepáticas Experimentais/imunologia , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/terapia , Masculino , Coelhos , Microambiente Tumoral
12.
Biochem J ; 474(18): 3137-3165, 2017 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-28887403

RESUMO

Reelin is a large extracellular matrix protein with relevant roles in mammalian central nervous system including neurogenesis, neuronal polarization and migration during development; and synaptic plasticity with its implications in learning and memory, in the adult. Dysfunctions in reelin signaling are associated with brain lamination defects such as lissencephaly, but also with neuropsychiatric diseases like autism, schizophrenia and depression as well with neurodegeneration. Reelin signaling involves a core pathway that activates upon reelin binding to its receptors, particularly ApoER2 (apolipoprotein E receptor 2)/LRP8 (low-density lipoprotein receptor-related protein 8) and very low-density lipoprotein receptor, followed by Src/Fyn-mediated phosphorylation of the adaptor protein Dab1 (Disabled-1). Phosphorylated Dab1 (pDab1) is a hub in the signaling cascade, from which several other downstream pathways diverge reflecting the different roles of reelin. Many of these pathways affect the dynamics of the actin and microtubular cytoskeleton, as well as membrane trafficking through the regulation of the activity of small GTPases, including the Rho and Rap families and molecules involved in cell polarity. The complexity of reelin functions is reflected by the fact that, even now, the precise mode of action of this signaling cascade in vivo at the cellular and molecular levels remains unclear. This review addresses and discusses in detail the participation of reelin in the processes underlying neurogenesis, neuronal migration in the cerebral cortex and the hippocampus; and the polarization, differentiation and maturation processes that neurons experiment in order to be functional in the adult brain. In vivo and in vitro evidence is presented in order to facilitate a better understanding of this fascinating system.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Diferenciação Celular , Membrana Celular/metabolismo , Movimento Celular , Citoesqueleto/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/citologia , Neurônios/fisiologia , Serina Endopeptidases/metabolismo , Animais , Transporte Biológico , Humanos , Proteína Reelina
13.
Am J Occup Ther ; 71(2): 7102220010p1-7102220010p8, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28218587

RESUMO

Parents of children with autism spectrum disorder (ASD) may have difficulty engaging their children through play, thus affecting the parent-child relationship and parental self-efficacy. This study intended to examine children's sensory profile and adults' playfulness as predictors of parental self-efficacy. A total of 136 parents of children ages 3-7 yr completed the Short Sensory Profile, the Playfulness Scale for Adults, and the Tool to Measure Parenting Self-Efficacy. For the parental couples of children with ASD, the most relevant predictor of general parental self-efficacy was the child's sensory profile. However, adult playfulness resulted in the most relevant predictor of emotional parental self-efficacy. Findings suggest the importance of considering play as a relevant co-occupation that must be acknowledged when intervening with families of children with ASD and considering the child's sensory modulation abilities, as well as parents' playfulness and sense of self-efficacy, as potential outcomes when designing and evaluating treatment programs.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Poder Familiar/psicologia , Pais/psicologia , Jogos e Brinquedos/psicologia , Autoeficácia , Sensação , Criança , Pré-Escolar , Emoções , Feminino , Humanos , Modelos Lineares , Masculino
14.
Arch Oral Biol ; 166: 106029, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38924874

RESUMO

OBJECTIVES: To develop a protocol for forming subsurface caries lesions on bovine enamel by dual-species biofilms of Streptococcus mutans and Candida albicans in vitro. DESIGN: Biofilms were grown on bovine enamel specimens in artificial saliva (AS) for seven days. After 24 h of formation, the AS was supplemented or not with fluoride (F) using sodium fluoride (0.005 or 0.008 ppm F), and the biofilms were exposed or not to a 20 % sucrose solution (reproducing a cariogenic challenge) once/day. On the seventh day, the biofilms were harvested and had their extracellular polysaccharides (EPS) and inorganic components analyzed. The specimens were subjected to computed X-ray microtomography analysis to determine their mineral concentration. Data were compared using two-way analyses of variance, followed by Fisher's LSD or Student-Newman-Keuls tests (p < 0.05). RESULTS: Biofilms exposed to the cariogenic challenge had significantly higher EPS concentrations than those not exposed, regardless of the presence of F. For biofilms grown with 0.008 ppm F, those exposed to the cariogenic challenge had lower F levels than those not exposed. For biofilms exposed to the cariogenic challenge, those grown with 0.008 ppm F had lower lesion depths and integrated mineral loss, and higher outer layers than those grown without F. CONCLUSIONS: The dual biofilm model assessed was able to create subsurface caries lesions in bovine enamel in vitro, which was influenced by the presence of F in the culture medium and exposure to sucrose.

15.
Sci Rep ; 13(1): 7579, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165035

RESUMO

Tumor recurrence affects up to 70% of early-stage hepatocellular carcinoma (HCC) patients, depending on treatment option. Deep learning algorithms allow in-depth exploration of imaging data to discover imaging features that may be predictive of recurrence. This study explored the use of convolutional neural networks (CNN) to predict HCC recurrence in patients with early-stage HCC from pre-treatment magnetic resonance (MR) images. This retrospective study included 120 patients with early-stage HCC. Pre-treatment MR images were fed into a machine learning pipeline (VGG16 and XGBoost) to predict recurrence within six different time frames (range 1-6 years). Model performance was evaluated with the area under the receiver operating characteristic curves (AUC-ROC). After prediction, the model's clinical relevance was evaluated using Kaplan-Meier analysis with recurrence-free survival (RFS) as the endpoint. Of 120 patients, 44 had disease recurrence after therapy. Six different models performed with AUC values between 0.71 to 0.85. In Kaplan-Meier analysis, five of six models obtained statistical significance when predicting RFS (log-rank p < 0.05). Our proof-of-concept study indicates that deep learning algorithms can be utilized to predict early-stage HCC recurrence. Successful identification of high-risk recurrence candidates may help optimize follow-up imaging and improve long-term outcomes post-treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Aprendizado de Máquina
16.
J Clin Transl Res ; 7(6): 717-722, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34901517

RESUMO

BACKGROUND: Post-intubation cardiac arrest (PICA) is an uncommon complication of intubation, but numbers have risen to over 1.5 times the usual number since the coronavirus disease 2019 (COVID-19) pandemic. Due to expert recommendations, high-dose rocuronium (HDR) has become a commonly used pre-intubation neuromuscular blocking agent. AIM: We conducted this retrospective case-control observational study with the hypothesis that high-dose rocuronium was not associated with higher incidence of PICA. METHODS: We included 93 patients who were intubated using the rapid sequence intubation (RSI) technique with rocuronium for acute respiratory distress syndrome (ARDS) due to confirmed COVID-19 pneumonia, admitted from March 2020 to February 2021 to a tertiary care hospital in North Carolina, USA. The patients were grouped based on high (1.5 mg/kg of ideal body weight and above) versus low (<1.5 mg/kg of ideal body weight) dose rocuronium used for RSI. The differences of the various outcomes between the groups were analyzed. RESULTS: The baseline demographics were similar in both groups except for higher body mass index in high-dose group 39 versus 32 (kg/m2), p = 0.009. There was a total of six PICA events (6.45%). The HDR group had 8.0% of PICA versus 4.7% in the low-dose group. In-hospital mortality was 60.0% in the HDR group versus 72.1% in the low-dose group. CONCLUSION: The incidence of PICA in COVID-19 patients with ARDS who were intubated using the RSI technique was higher than in the pre-COVID-19 era. RELEVANCE FOR PATIENTS: The use of high-dose paralytics during invasive ventilation with RSI and their consequences should be explored with the help of large-scale studies. The rate of PICA is still very low, and perhaps, the use of HDR is safe, as suggested by the expert panel.

17.
Rev Bras Enferm ; 73(3): e20180656, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32321122

RESUMO

OBJECTIVES: to describe the expressions recognized by domestic violence educators experienced by school adolescents. METHODS: it is a qualitative study based on Paulo Freire's liberating pedagogy. Semi-structured interviews were conducted with 20 teachers from a public elementary school in the city of Salvador, state of Bahia, Brazil. The data were systematized through the Discourse of the Collective Subject. RESULTS: collective discourse reveals that educators identify schoolchildren who experience physical, psychological and negligent abuse, being denied even love and affection. CONCLUSIONS: although not alluding to sexual abuse, educators recognize that students are inserted in the context of domestic violence, knowledge necessary for the development of actions that enable the exit of the student from the oppressed and overcoming the lived experience.


Assuntos
Comportamento do Adolescente/psicologia , Violência Doméstica/classificação , Violência Doméstica/psicologia , Estudantes/psicologia , Adolescente , Brasil , Criança , Feminino , Humanos , Masculino , Pesquisa Qualitativa , Instituições Acadêmicas/organização & administração , Instituições Acadêmicas/estatística & dados numéricos
18.
Acta Trop ; 211: 105594, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32598917

RESUMO

Congenital toxoplasmosis is a parasitic disease caused by Toxoplasma gondii, an obligate intracellular parasite which can cause fetal death/abortion and can induce damage in the brain and eyes of the infected babies. The environmental and genetic factors associated with T. gondii and the maternal immune response, drive part of the pathogenesis of congenital toxoplasmosis. Thus, in this study, we aimed to investigate the allelic and genotypic frequencies of specific single nucleotide polymorphisms (SNPs) in the IL17A and IL17RA genes, as well as the production of IL-17A, IL-33, and CCL2 in pregnant women, from the State of Rio Grande do Norte, Brazil, further relating these along with the clinical parameters, to the toxoplasmosis infection. Through PCR-RFLP techniques, two SNPs implicated in Th17 immune response, IL17A rs2275913 (G> A) and IL17RA rs4819554 (A> G) modulation were evaluated in pregnant women, either infected or not infected by T. gondii. These women were also evaluated in terms of plasma release of CCL2, IL-33, and IL-17A which relate to hypertension, number of abortions, and ethnic pattern. The results showed that the G-allele of the SNP rs2275913 (IL17A) appeared to be protective in this population, while the rs4819554 (IL17RA) SNP G allele was associated with greater susceptibility to T. gondii infection [ρ value = 0.025; OR = 2.815 (1.118-7.089); CI = 95%]. None of the cytokines had any influence on the analyzed parameters (abortion and hypertension). In conclusion, our data suggest an immunogenic evidence of susceptibility to T. gondii infection driven by the rs4819554 (IL17RA) SNP G allele in Brazilian pregnant women. Further studies are needed to reinforce this trial marker in populations from distinct geographical areas as well as to confirm the protective pattern related to the G-allele of the SNP rs2275913 (IL17A) in pregnant women.


Assuntos
Predisposição Genética para Doença , Complicações Parasitárias na Gravidez/genética , Receptores de Interleucina-17/metabolismo , Toxoplasmose/genética , Adulto , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Citocinas/genética , Feminino , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Gestantes , Receptores de Interleucina-17/genética , Toxoplasma/imunologia , Adulto Jovem
19.
Chronobiol Int ; 35(7): 996-1007, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29565681

RESUMO

This study analyzed the fluctuation of the achromatic visual contrast sensitivity (CS) of adult males (M = 23.42 ± 2.6 years) during a daily period. Twenty-eight volunteers were divided into three groups according to circadian typology (CT): moderate morning (MM; n = 8); intermediate (I; n = 10) and moderate evening (ME; n = 10). The Pittsburgh Sleep Quality Index was used to evaluate sleep quality, and the Horne and Ostberg Morningness-Eveningness Questionnaire was used to measure CT. To measure CS, we used Metropsis software version 11.0 with vertical sinusoidal grids of 0.2, 0.6, 1, 3.1, 6.1, 8.8, 13.2 and 15.6 cycles per degree of visual angle (cpd). The stimuli were presented on a cathode ray tube (CRT) color video monitor with a 19-inch flat screen, a 1024 × 786 pixel resolution, a 100 Hz refresh rate and a photopic luminance of 39.6 cd/m2. It was inferred that there is a tendency for visual contrast to vary according to daily rhythmicity and CT, mainly for the median spatial frequencies (1.0 cpd, χ2 = 9.93, p < 0.05 and 3.1 cpd, χ2 = 10.33, p < 0.05) and high spatial frequencies (13.2 cpd, χ2 = 11.54, p < 0.05) of ME participants. ME participants had minimal visual contrast sensitivity during the morning shift and a progressive increase from afternoon to night.


Assuntos
Ritmo Circadiano/fisiologia , Sono/fisiologia , Fatores de Tempo , Percepção Visual/fisiologia , Adulto , Humanos , Masculino , Psicofísica/métodos , Inquéritos e Questionários , Adulto Jovem
20.
Front Psychol ; 9: 288, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29559947

RESUMO

Smoking prevalence in patients who are diagnosed with schizophrenia (SCZ) is higher than in the general population. Chronic tobacco use in SCZ patients may reduce the side effects of antipsychotic drugs, thus serving as a self-medication for such side effects. Understanding the ways in which chronic tobacco use influences visual sensitivity has clinical implications, which may serve as a tool for non-invasively diagnosing early-stage visual processing deficits. The present study evaluated the effects of chronic tobacco use on visual sensitivity in SCZ patients. Our purpose was to provide new directions for future research, mainly psychophysical and electrophysiological studies. In the present study, 40 smoker controls (SC), 20 SCZ tobacco users, and 20 SCZ tobacco nonusers were recruited from the Psychosocial Care Center. Visual sensitivity was compared between both SCZ groups and the SC group. Patients with SCZ who were chronic tobacco users presented lower visual sensitivity for chromatic (p < 0.001) and achromatic (p < 0.001) stimuli compared with the other groups. Our findings highlight the need to evaluate possible addictive behavior in patients with SCZ, which may contribute to public policies that seek to improve the quality of life of SCZ patients and their families.

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