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1.
Langmuir ; 40(15): 8225-8232, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38584357

RESUMO

This study proposes a robust microshell encapsulation system in which a metal-organic membrane (MOM), consisting of phytic acids (PAs) and metal ions, intrinsically prevents the molecular crystal growth of organic crystalline materials (OCMs). To develop this system, OCM-containing oil-in-water (O/W) Pickering emulsions were enveloped with the MOM, in which anionic pulp cellulose nanofiber (PCNF) primers electrostatically captured zinc ions at the O/W interface and chelated with PA, thus producing the MOM with a controlled shell thickness at the micron scale. We ascertained that the MOM formation fills and covers ∼75% of the surface pore size of PCNF films, which enhances the interfacial modulus by 2 orders of magnitude compared to that when treated with bare PCNFs. Through a feasibility test using a series of common OCMs, including ethylhexyl triazone, avobenzone, and ceramide, we demonstrated the excellent ability of our MOM microshell system to stably encapsulate OCMs while retaining their original molecular structures over time. These findings indicate that our MOM-reinforced microshell technology can be applied as a platform to substantially confine the crystal growth of various types of OCMs.

2.
Neurocrit Care ; 40(2): 538-550, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37353670

RESUMO

BACKGROUND: Early identification of the severity of hypoxic-ischemic brain injury (HIBI) after cardiac arrest can be used to help plan appropriate subsequent therapy. We evaluated whether conductivity of cerebral tissue measured using magnetic resonance-based conductivity imaging (MRCI), which provides contrast derived from the concentration and mobility of ions within the imaged tissue, can reflect the severity of HIBI in the early hours after cardiac arrest. METHODS: Fourteen minipigs were resuscitated after 5 min or 12 min of untreated cardiac arrest. MRCI was performed at baseline and at 1 h and 3.5 h after return of spontaneous circulation (ROSC). RESULTS: In both groups, the conductivity of cerebral tissue significantly increased at 1 h after ROSC compared with that at baseline (P = 0.031 and 0.016 in the 5-min and 12-min groups, respectively). The increase was greater in the 12-min group, resulting in significantly higher conductivity values in the 12-min group (P = 0.030). At 3.5 h after ROSC, the conductivity of cerebral tissue in the 12-min group remained increased (P = 0.022), whereas that in the 5-min group returned to its baseline level. CONCLUSIONS: The conductivity of cerebral tissue was increased in the first hours after ROSC, and the increase was more prominent and lasted longer in the 12-min group than in the 5-min group. Our findings suggest the promising potential of MRCI as a tool to estimate the severity of HIBI in the early hours after cardiac arrest.


Assuntos
Lesões Encefálicas , Reanimação Cardiopulmonar , Parada Cardíaca , Humanos , Animais , Suínos , Estudos de Viabilidade , Porco Miniatura , Parada Cardíaca/diagnóstico por imagem , Parada Cardíaca/terapia , Espectroscopia de Ressonância Magnética , Reanimação Cardiopulmonar/métodos
3.
Small ; 19(50): e2304120, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37649189

RESUMO

Phase change materials (PCMs) have attracted significant attention as promising insulating materials. However, they often suffer from the simple yet critical problem of leakage in practical applications. Therefore, in this study, an injectable PCM emulsion insulation platform is developed. For this, n-hexadecane, as a PCM, emulsion droplets are armored with a metal-organic membrane (MOM) through the coordination of zinc ions and phytic acid. The MOM layer not only provides a rigid interfacial modulus but also allows the emulsion to exhibit viscoelastic behavior by shear stress-induced interdrop association. This MOM-enveloped PCM emulsion (PCMEMOM ) exhibited typical sol-gel transition behavior in response to applied shear stress, indicating the injectable characteristic of the PCMEMOM . After observing the rheological hysteresis and thermal stability of the PCMEMOM under repetitive heating and cooling cycles, the thermal insulation performance of PCMEMOM is quantitatively and visually demonstrated. These findings suggest an efficient method to exploit high-performance insulation systems.

4.
Langmuir ; 39(16): 5670-5678, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37053540

RESUMO

This study introduces a promising approach to stabilize high internal phase emulsions (HIPEs) in which droplets are enveloped by octadecane (C18)-grafted bacterial cellulose nanofibers (BCNFdiC18), which are mainly surrounded by carboxylate anions and hydrophobically modified with C18 alkyl chains. For this purpose, BCNFdiC18, in which two octadecyl chains were grafted onto each of several cellulose unit rings on 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidized BCNFs, was fabricated using the Schiff base reaction. The wettability of BCNFdiC18 was adjusted by controlling the amount of the grafted C18 alkyl chain. Interfacial rheological analysis revealed that BCNFdiC18 enhanced the membrane modulus at the oil-water interface. We figured out that such a resilient interfacial membrane substantially prevented interdrop fusion across the water drainage channel formed between the jammed oil droplets, which was confirmed theoretically using the modified Stefan-Reynolds equation. These findings highlight that the use of surfactants in the form of nanofibers to form a rigid interfacial film plays a key role in hindering the interfusion of the internal phase and the collapse of the emulsion, which is essential for HIPE stabilization.

5.
J Magn Reson Imaging ; 56(6): 1781-1791, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35543163

RESUMO

BACKGROUND: The assessment of liver surface nodularity (LSN) for staging hepatic fibrosis is restricted in clinical practice because it requires customized software and time-consuming procedures. A simplified method to estimate LSN score may be useful in the clinic. PURPOSE: To evaluate the regional analysis of LSN and processing time in a single axial liver MR image for staging liver fibrosis. STUDY TYPE: Retrospective. POPULATION: A total of 210 subjects, a multicenter study. FIELD STRENGTH/SEQUENCE: A 3 T/noncontrast gradient echo T1WI. ASSESSMENT: Subjects were divided into five fibrosis groups (F0  = 29; F1  = 20; F2  = 32; F3  = 50; F4  = 79) based on the METAVIR fibrosis scoring system. The mean LSN (on three slices) and regional LSN (on one slice) measurements, and the processing times, are compared. The regional LSN scores in five regions-of-interests (ROI1-5 ) were analyzed in a single axial MRI at the level of the hilum by two independent observers. STATISTICAL TESTS: Regional variations in LSN scores were compared using ANOVA with Tukey test. Agreement between the mean and regional LSN measurements was evaluated using Pearson correlation coefficients (r) and Bland-Altman plots. The diagnostic performance of mean and regional LSN scores according to fibrosis stage was evaluated with the AUROC. A P value < 0.05 was considered statistically significant. RESULTS: Total processing time for a regional LSN measurement (3.6 min) was 75.5% less than that for mean LSN measurement (14.7 min). Mean LSN scores and all five regional LSN scores showed significant differences between fibrosis groups. Among regional LSN scores, ROI5 showed the highest AUROC (0.871 at cut-off 1.12) for discriminating F0-2 vs. F3-4 and the best correlation with mean LSN score (r = 0.800, -0.07 limit of agreement). CONCLUSION: Quantitative regional LSN measurement in a single axial MR image reduces processing time. Regional ROI5 LSN score might be useful for clinical decision-making and for distinguishing the difference between early fibrosis (F0-2 ) and advanced fibrosis (F3-4 ) in the liver. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Cirrose Hepática , Fígado , Humanos , Estudos Retrospectivos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Imageamento por Ressonância Magnética , Fibrose
6.
Macromol Rapid Commun ; 43(7): e2100917, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35213061

RESUMO

This study introduces a cellulose nanofiber surfactant system, in which the surface is hydrophobically modified with different alkyl chain structures for the effective envelopment of solid lipid microparticles (SLMs). To endow bacterial cellulose nanofibers (BCNFs) with excellent ability to assemble at the lipid-water interface, alkyl chains with designated molecular structures, such as decane, didecane, and eicosane, are covalently grafted onto the BCNF surface. Interfacial tension and interfacial rheology measurements indicate that dialkyl chain-grafted BCNFs (diC10 BCNF) exhibit strong interfibrillar association at the interface. The formation of a dense and tough fibrillary membrane contributes significantly to the enveloping of the SLMs, regardless of the lipid type. Because the diC10 BCNF-enveloped SLMs exhibit a core molecular crystalline phase at the microscale, they can immobilize an oil-soluble antioxidant while maintaining its long-term storage stability. These findings show that the cellulose-surfactant-based SLM technology is applicable to the stabilization and formulation of readily denatured active ingredients.


Assuntos
Nanofibras , Antioxidantes , Bactérias , Celulose/química , Lipídeos , Nanofibras/química
7.
J Magn Reson Imaging ; 53(2): 554-563, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32614131

RESUMO

BACKGROUND: Liver fibrosis is characterized by the excessive accumulation of extracellular matrix proteins. Electrical conductivity imaging at low frequency can provide novel contrast because the contrast mechanisms originate from the changes in the concentration and mobility of ions in the extracellular space. PURPOSE: To evaluate the feasibility of an MR-based electrical conductivity imaging that can detect the changes in a tissue condition associated with the progression of liver fibrosis. STUDY TYPE: Prospective phantom and animal study. ANIMAL MODEL: Fibrosis was induced by weekly intraperitoneal injection of dimethylnitrosamine (DMN) in 45 male Sprague-Dawley rats. FIELD STRENGTH/SEQUENCE: 3T MRI with a multispin-echo pulse sequence. ASSESSMENT: The percentage change of conductivity (Δσ, %) in the same region-of-interest (ROI) was calculated from the DMN-treated rats based on the values of the normal control rats. The percentage change was also calculated between the ROIs in each DMN-treated group. STATISTICAL TESTS: One-way analysis of variance (ANOVA) and a two-sample t-test were performed. RESULTS: Liver tissues in normal control rats showed a uniform conductivity distribution of 56.6 ± 4.4 (mS/m). In rats more than 5 weeks after induction, the fibrous region showed an increased conductivity of ≥12% compared to that of the corresponding normal control rats. From regional comparisons in the same liver, the fibrous region showed an increased conductivity of ≥11% compared to the opposite, less induced region of rats more than 5 weeks after induction. Liver samples from the fibrous region represent tissue damages such as diffuse centrilobular congestion with marked dilatation of central veins from the histological findings. Immunohistochemistry revealed significant levels of attenuated fibrosis and increased inflammatory response. DATA CONCLUSION: The increased conductivity in the fibrous region is related to the changes of the extracellular space. The correlation between the collagen deposition and conductivity changes is essential for future clinical studies. Level of Evidence 2 Technical Efficacy Stage 2 J. MAGN. RESON. IMAGING 2021;53:554-563.


Assuntos
Dimetilnitrosamina , Cirrose Hepática , Animais , Condutividade Elétrica , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Masculino , Estudos Prospectivos , Ratos , Ratos Sprague-Dawley
8.
Langmuir ; 37(13): 3828-3835, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33780257

RESUMO

In this study, we present a water-in-silicone oil (W/S) Pickering emulsion system stabilized via in situ interfacial coacervation of attractive hectorite nanoplatelets (AHNPs) and bacterial cellulose nanofibrils (BCNFs). A bilayered coacervate is generated at the W/S interface by employing the controlled electrostatic interaction between the positively charged AHNPs and the negatively charged BCNFs. The W/S interface with the bilayered coacervate shows a significant increase in the interfacial modulus by 2 orders of magnitude than that with the AHNPs only. In addition, we observe that water droplets are interconnected by the BCNF bridging across the continuous phase of silicon, which is attributed to the diffusive transport phenomenon. This droplet interconnection results in the effective prevention of drop coalescence, which is confirmed via emulsion sedimentation kinetics. These results indicate that our bilayered coacervation technology has the potential of developing a promising Pickering emulsion platform that can be used in the pharmaceutical and cosmetic industries.

9.
Small ; 16(9): e1904282, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31755646

RESUMO

Boston ivy (Parthenocissus tricuspidata) climbs brick walls using its tendril disks, which excrete a sticky substance to perform binding and attachment. While the cellular structures and adhesive substances involved have been identified for decades, their practical applicability as an adhesive has not yet been demonstrated. A Boston ivy disk-inspired adhesive film patch system is reported in which structural and compositional features of the Boston ivy disk are mimicked with a form of thin adhesive film patches. In analogy to the sticky disk of a mature ivy in which porous microchannels are occupied by catechol-containing microgranules on the bound site, 3,4-dihydroxylphenylalanine bolaamphiphile nanoparticle (DOPA-C7 NP)-coated alginate microgels are two-dimensionally positioned into the cylindrical holes that are periodically micropatterned on the flexible stencil film. Finally, it is demonstrated that the pressurization of the patch breaks the microgels filled in the holes, releasing the polysaccharides and leading to crosslinking with DOPA-C7 NPs via ligandation with combined Ca2+ and Fe3+ ions, thus enabling development of a pressure-mediated adhesion technology.


Assuntos
Adesivos , Alginatos , Microgéis , Adesivos/química , Alginatos/química , Microgéis/química , Extratos Vegetais/química , Pressão , Vitaceae/química
10.
Opt Express ; 28(24): 36327-36345, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379729

RESUMO

In this paper, we propose a new method for coding a full complex hologram with random phase. Since holograms with random phase have very unique spatial and frequency characteristics, a new compression method suitable for such holograms is required. We analyze the frequency characteristics of holograms with random phases and propose a new adaptive discrete wavelet transform (aDWT). Next, we propose a new modified zerotree alogrithm (mZTA) suitable for the subband configuration generated by the modified wavelet transform method. The results of the compression using the proposed method showed higher efficiency than the previous method, and the reconstructed images showed visually superior results.

11.
J Vasc Interv Radiol ; 31(10): 1636-1644.e1, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32943296

RESUMO

PURPOSE: To retrospectively investigate incidence, clinical outcome, and risk factors of iatrogenic pleural effusion in patients with hepatic tumors undergoing radiofrequency (RF) ablation using artificial ascites (AA). MATERIALS AND METHODS: Patients (N = 163) who underwent RF ablation using AA were classified into pleural effusion and non-pleural effusion groups according to the presence of pleural effusion on immediate follow-up CT and chest radiograph after RF ablation. The pleural effusion group included asymptomatic and symptomatic subgroups. The incidence and subsequent clinical outcomes of patients developing pleural effusion after RF ablation were evaluated. RESULTS: Overall, 96 patients (58.9%) developed pleural effusion, which resolved in 4.4 d ± 3.1. Hospital length of stay in the pleural effusion group was longer than the non-pleural effusion group (6.5 d ± 2.6 vs 5.7 d ± 2.8, P < .01). The pleural effusion group had longer AA infusion time (P = .01), larger infused AA volume (P < .01), and longer ablation time (P < .01) than the non-pleural effusion group. Eighteen patients (18.8%) developed symptomatic pleural effusion and had a larger infused AA volume than asymptomatic patients with pleural effusion (P < .01). Pleural effusion duration and hospital length stay were also longer in the symptomatic pleural effusion subgroup than in the asymptomatic subgroup (P < .01). Infused AA volume was the only independent prognostic factor of pleural effusion duration in multivariate analysis (P = .038). CONCLUSIONS: Pleural effusion frequently occurs after RF ablation using AA. Although generally considered negligible, pleural effusion could be a clinical problem and prolong hospitalization. Therefore, operators should be careful not to infuse too much AA when performing RF ablation.


Assuntos
Ascite , Doença Iatrogênica/epidemiologia , Neoplasias Hepáticas/cirurgia , Derrame Pleural/epidemiologia , Ablação por Radiofrequência/efeitos adversos , Idoso , Feminino , Humanos , Incidência , Infusões Parenterais , Tempo de Internação , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Derrame Pleural/diagnóstico por imagem , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
12.
Eur Radiol ; 29(5): 2399-2407, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30617492

RESUMO

OBJECTIVES: To define and correlate multidetector CT (MDCT) findings of pancreatic fistula after pancreaticoduodenectomy with surgical grading based on the 2016 Revised International Study Group of Pancreatic Fistula (ISGPF) classification. METHODS: Between May 2011 and December 2016, 235 patients with periampullary tumor underwent pancreaticoduodenectomy and postoperative MDCT. Patients were classified into three groups (clinically no pancreatic fistula (cNo-PF), grade B, and grade C) according to the ISGPF classification. MDCT images were retrospectively evaluated by two radiologists in consensus for the presence of pancreaticojejunostomy (PJ) dehiscence, PJ dehiscence diameter, PJ defect, acute necrotic collection (ANC), peripancreatic fluid collection, and imaging findings of complications. Categorical MDCT findings were compared among the three groups using Pearson's chi-square test, and PJ dehiscence diameter was compared using the Kruskal-Wallis test. RESULTS: There was no significant difference in patient demographics among the groups (cNo-PF = 133, grade B = 68, and grade C = 34), but the MDCT findings were significantly different regarding the presence of PJ dehiscence (p < 0.001), PJ defect (p < 0.001), ANC (p = 0.002), and imaging findings of total complications (p < 0.001). The diameters of PJ dehiscence were significantly different among the groups (cNo-PF [0.42 ± 1.54 mm], grade B [1.47 ± 2.33 mm], and grade C [5.38 ± 6.45 mm]) (p < 0.001). CONCLUSION: With respect to the presence of PF, postoperative MDCT findings may differ between surgical grading based on the ISGPF classification. KEY POINTS: • Regarding the presence of pancreatic fistula, the postoperative multidetector CT findings correlate well with surgical grading based on the International Study Group of Pancreatic Fistula classification. • Multidetector CT may provide reliable information to suggest pancreatic fistula after pancreaticoduodenectomy.


Assuntos
Tomografia Computadorizada Multidetectores/métodos , Fístula Pancreática/diagnóstico , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Pancreática/etiologia , Fístula Pancreática/cirurgia , Neoplasias Pancreáticas/diagnóstico , Curva ROC , Reoperação , Estudos Retrospectivos , Adulto Jovem
13.
J Vasc Interv Radiol ; 30(3): 284-292.e1, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30819467

RESUMO

PURPOSE: To retrospectively compare long-term outcomes of conventional chemoembolization plus radiofrequency (RF) ablation vs those of surgical resection in patients with a single 3-5-cm hepatocellular carcinoma (HCC). MATERIALS AND METHODS: From January 2008 to December 2017, 139 of 623 patients who underwent surgical resection and 60 of 186 patients who underwent chemoembolization/RF ablation in a single center were compared with respect to local tumor progression (LTP), intrahepatic distant recurrence (IDR), disease-free survival (DFS), overall survival (OS), major complications, and hospital stay before and after propensity-score matching. RESULTS: Mean follow-up periods were similar in the chemoembolization/RF ablation and surgical resection groups (41.9 mo vs 48.4 mo). Three (5%) and 17 (28.3%) patients in the chemoembolization/RF ablation group and 12 (8.6%) and 57 (41.0%) patients in the surgical resection group showed LTP and IDR (P = .366 and P =.114, respectively). At 1, 3, and 5 years, respective DFS rates were 88.1%, 65.3%, and 49.0% for chemoembolization/RF ablation and 84.2%, 58.2%, and 46.5% for surgical resection (P = .294). Moreover, respective OS rates were 95.0%, 73.5%, and 54.0% for chemoembolization/RF ablation and 97.1%, 87.4%, and 75.0% for surgical resection (P = .055). After matching (n = 52), therapeutic outcomes remained similar (P = .370, P = .110, P = .230, and P = .760, respectively). Surgical resection was associated with higher complication rates (P = .015) and longer hospital stays (8.4 d ± 3.7 vs 16.9 d ± 7.0; P < .001). CONCLUSIONS: Conventional chemoembolization combined with RF ablation may be feasible for single 3-5-cm HCCs, with comparable therapeutic outcomes vs surgical resection and shorter hospital stays.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Hepatectomia , Neoplasias Hepáticas/terapia , Ablação por Radiofrequência , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/secundário , Quimioembolização Terapêutica/efeitos adversos , Quimioembolização Terapêutica/mortalidade , Progressão da Doença , Intervalo Livre de Doença , Feminino , Hepatectomia/efeitos adversos , Hepatectomia/mortalidade , Humanos , Tempo de Internação , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Complicações Pós-Operatórias/etiologia , Ablação por Radiofrequência/efeitos adversos , Ablação por Radiofrequência/mortalidade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Carga Tumoral
14.
J Vasc Interv Radiol ; 30(3): 370-379.e4, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30819479

RESUMO

PURPOSE: To evaluate the effects of the degree of ethiodized oil accumulation achieved by transarterial chemoembolization followed by radiofrequency (RF) ablation on the treatment efficacy for a single intermediate-sized hepatocellular carcinoma (HCC). MATERIALS AND METHODS: A total of 153 consecutive patients who underwent chemoembolization and RF ablation for a single intermediate-sized HCC (2-5 cm) were included. On the basis of the degree of ethiodized oil accumulation in HCC on cone-beam CT images, patients who underwent chemoembolization and RF ablation were classified into 2 groups: compact accumulation (≥ 75%) and noncompact accumulation (< 75%). The rates of cumulative local tumor progression (LTP), disease-free survival (DFS), and overall survival (OS) were compared between groups. RESULTS: Of the 153 patients, 89 were classified into the compact ethiodized oil accumulation group and 64 in the noncompact ethiodized oil accumulation group. There were no significant differences in patient demographic or HCC characteristics between groups except for the incidence of liver cirrhosis (P = .038) and the tumor margin morphology (P = .008). The cumulative LTP rate was significantly lower in the compact accumulation group than in the noncompact accumulation group (P = .013). There were no significant differences in the incidences of complications, DFS rates (P = .055), or OS rates (P = .184). CONCLUSIONS: The degree of ethiodized oil accumulation does not play a role in decreasing the OS or DFS rate after chemoembolization and RF ablation for intermediate-sized HCC; however, it may contribute to reducing the rate of LTP.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Óleo Etiodado/administração & dosagem , Neoplasias Hepáticas/terapia , Ablação por Radiofrequência , Idoso , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica/efeitos adversos , Quimioembolização Terapêutica/mortalidade , Tomografia Computadorizada de Feixe Cônico , Óleo Etiodado/efeitos adversos , Óleo Etiodado/metabolismo , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Ablação por Radiofrequência/efeitos adversos , Ablação por Radiofrequência/mortalidade , República da Coreia , Estudos Retrospectivos , Fatores de Tempo , Distribuição Tecidual , Carga Tumoral
15.
AJR Am J Roentgenol ; 213(4): 746-754, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31039020

RESUMO

OBJECTIVE. The purpose of this study is to quantitatively assess perfusion reductions occurring in hepatocellular carcinoma (HCC) during transcatheter arterial chemoembolization (TACE) using 2D perfusion angiography and to evaluate the relationships between various 2D perfusion angiography parameter changes and short-term tumor response. SUBJECTS AND METHODS. This prospective study included 172 patients (144 men and 28 women; mean [± SD] age, 65.4 ± 10.2 years) who underwent TACE for HCC between November 2015 and November 2017. Two-dimensional perfusion angiography was performed before and after TACE. Pre- and postprocedural CT images were also reviewed. Index lesions were defined as all discrete lesions 1.5 cm or larger. The tumor response was assessed using the modified Response Evaluation Criteria in Solid Tumors. Periprocedural 2D perfusion angiography parameters, including the arrival time, time to peak, wash-in rate, width, AUC, and mean transit time, were compared using the Wilcoxon signed rank test. Correlations between 2D perfusion angiography parameter changes and objective tumor response were evaluated using multivariate logistic regression analysis. RESULTS. A total of 187 lesions meeting the inclusion criteria were identified in 172 patients. All analyzed 2D perfusion angiography parameters were significantly different after versus before TACE (p < 0.001). A significant relationship between periprocedural change in AUC and short-term tumor response was found (odds ratio, 1.535; 95% CI, 1.314-1.793; p < 0.001). CONCLUSION. Two-dimensional perfusion angiography could objectively quantify perfusion reductions and predict short-term tumor response to TACE in patients with HCC.


Assuntos
Angiografia/métodos , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Imagem de Perfusão/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Doxorrubicina/administração & dosagem , Óleo Etiodado/administração & dosagem , Feminino , Esponja de Gelatina Absorvível/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Interpretação de Imagem Radiográfica Assistida por Computador , Critérios de Avaliação de Resposta em Tumores Sólidos
16.
BMC Urol ; 19(1): 95, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31638952

RESUMO

BACKGROUND: Electrical conductivity-based magnetic resonance (MR) imaging may provide unique information on tissue condition because its contrast originates from the concentration and mobility of ions in the cellular space. We imaged the conductivity of normal canine prostate in vivo and evaluated tissue contrast in terms of both the conductivity distribution and anatomical significance. METHODS: Five healthy laboratory beagles were used. After clipping the pelvis hair, we attached electrodes and placed each dog inside the bore of an MRI scanner. During MR scanning, we injected imaging currents into two mutually orthogonal directions between two pairs of electrodes. A multi spin echo pulse sequence was used to obtain the MR magnitude and magnetic flux density images. The projected current density algorithm was used to reconstruct the conductivity image. RESULTS: Conductivity images showed unique contrast depending on the prostatic tissues. From the conductivity distribution, conductivity was highest in the center area and lower in the order of the middle and outer areas of prostatic tissues. The middle and outer areas were, respectively, 11.2 and 25.5% lower than the center area. Considering anatomical significance, conductivity was highest in the central zone and lower in the order of the transitional and peripheral zones in all prostates. The transitional and peripheral zones were, respectively, 7.5 and 17.8% lower than the central zone. CONCLUSIONS: Current conductivity-based MR imaging can differentiate prostatic tissues without using any contrast media or additional MR scans. The electrical conductivity images with unique contrast to tissue condition can provide a prior information on tissues in situ to be used for human imaging.


Assuntos
Imageamento por Ressonância Magnética/métodos , Próstata/anatomia & histologia , Próstata/diagnóstico por imagem , Animais , Cães , Condutividade Elétrica , Estudos de Viabilidade , Masculino
17.
Small ; 14(16): e1800026, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29570235

RESUMO

There is an increasing demand for control over the dimensions and functions of transition metal dichalcogenides (TMDs) in aqueous solution toward biological and medical applications. Herein, an approach for the exfoliation and functionalization of TMDs in water via modulation of the hydrophobic interaction between poly(ε-caprolactone)-b-poly(ethylene glycol) (PCL-b-PEG) and the basal planes of TMDs is reported. Decreasing the hydrophobic PCL length of PCL-b-PEG from 5000 g mol-1 (PCL5000 ) to 460 g mol-1 (PCL460 ) significantly increases the exfoliation efficiency of TMD nanosheets because the polymer-TMD hydrophobic interaction becomes dominant over the polymer-polymer interaction. The TMD nanosheets exfoliated by PCL460 -b-PEG5000 (460-WS2 , 460-WSe2 , 460-MoS2 , and 460-MoSe2 ) show excellent and prolonged scavenging activity for reactive oxygen species (ROS), but each type of TMD displays a different scavenging tendency against hydroxyl, superoxide, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals. A mechanistic study based on electron paramagnetic resonance spectroscopy and density functional theory simulations suggests that radical-mediated oxidation of TMDs and hydrogen transfer from the oxidized TMDs to radicals are crucial steps for ROS scavenging by TMD nanosheets. As-prepared 460-TMDs are able to effectively scavenge ROS in HaCaT human keratinocytes, and also exhibit excellent biocompatibility.


Assuntos
Nanoestruturas/química , Polímeros/química , Espécies Reativas de Oxigênio/química , Elementos de Transição/química , Linhagem Celular , Humanos , Radical Hidroxila/química , Superóxidos/química
18.
BMC Cancer ; 18(1): 173, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29433469

RESUMO

BACKGROUND: Brain metastases from gastric cancer are difficult to treat and their prognosis is poor. Despite various possible treatments, the survival rate of such patients is still unsatisfactory; therefore, new treatment modalities or combinations of therapies need to be explored. CASE PRESENTATION: We herein discuss a case of a 38-year-old man initially diagnosed with a gastric cancer brain metastasis. At first, only stereotactic radiosurgery (SRS) was performed, but it was not effective. After the brain and systemic metastases progressed, SRS and anti-PD-1 therapy were administered in combination, and the brain and intra-abdominal metastatic lesions responded satisfactorily. CONCLUSION: The combination of anti-PD-1 therapy and SRS could be effective against gastric cancer with brain metastases.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia , Terapia de Alvo Molecular , Radiocirurgia , Neoplasias Gástricas/patologia , Adulto , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antígeno B7-H1/antagonistas & inibidores , Biópsia , Neoplasias Encefálicas/diagnóstico , Terapia Combinada , Humanos , Imageamento por Ressonância Magnética , Masculino , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
19.
Biomacromolecules ; 19(2): 386-391, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29300089

RESUMO

Embolization is a nonsurgical, minimally invasive procedure that deliberately blocks a blood vessel. Although several embolic particles have been commercialized, their much wider applications have been hampered owing mainly to particle size variation and uncontrollable degradation kinetics. Herein we introduce a microfluidic approach to fabricate highly monodisperse gelatin microparticles (GMPs) with a microshell structure. For this purpose, we fabricate uniform gelatin emulsion precursors using a microfluidic technique and consecutively cross-link them by inbound diffusion of glutaraldehyde from the oil continuous phase to the suspending gelatin precursor droplets. A model micromechanic study, carried out in an artificial blood vessel, demonstrates that the extraordinary degradation kinetics of the GMPs, which stems from the microshell structure, enables controlled rupturing while exhibiting drug release under temporary chemoembolic conditions.


Assuntos
Cápsulas/química , Quimioembolização Terapêutica/métodos , Gelatina/química , Células 3T3 , Animais , Cápsulas/administração & dosagem , Reagentes de Ligações Cruzadas/química , Liberação Controlada de Fármacos , Emulsões/química , Glutaral/química , Camundongos , Microfluídica
20.
Biomacromolecules ; 19(7): 2682-2690, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29847726

RESUMO

We herein propose a polymeric nanovehicle system that has the ability to remarkably improve cellular uptake and transdermal delivery. Cell-penetrating peptide-patchy deformable polymeric nanovehicles were fabricated by tailored coassembly of amphiphilic poly(ethylene oxide)- block-poly(ε-caprolactone) (PEO- b-PCL), mannosylerythritol lipid (MEL), and YGRKKRRQRRR-cysteamine (TAT)-linked MEL. Using X-ray diffraction, differential scanning calorimetry, and nuclear magnetic resonance analyses, we revealed that the incorporation of MEL having an asymmetric alkyl chain configuration was responsible for the deformable phase property of the vehicles. We also discovered that the nanovehicles were mutually attracted, exhibiting a gel-like fluid characteristic due to the dipole-dipole interaction between the hydroxyl group of MEL and the methoxy group of PEO- b-PCL. Coassembly of TAT-linked MEL with the deformable nanovehicles significantly enhanced cellular uptake due to macropinocytosis and caveolae-/lipid raft-mediated endocytosis. Furthermore, the in vivo skin penetration test revealed that our TAT-patchy deformable nanovehicles remarkably improved transdermal delivery efficiency.


Assuntos
Glicolipídeos/química , Nanopartículas/química , Fragmentos de Peptídeos/administração & dosagem , Poliésteres/química , Absorção Cutânea , Produtos do Gene tat do Vírus da Imunodeficiência Humana/administração & dosagem , Administração Cutânea , Adulto , Linhagem Celular , Cisteamina/química , Feminino , Humanos , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacocinética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/química , Produtos do Gene tat do Vírus da Imunodeficiência Humana/farmacocinética
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