Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 208
Filtrar
1.
Inorg Chem ; 63(6): 2899-2908, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38127051

RESUMO

The energetic and geometric features enabling redox chemistry across the copper cupredoxin fold contain key components of electron transfer chains (ETC), which have been extended here by templating the cross-ß bilayer assembly of a synthetic nonapeptide, HHQALVFFA-NH2 (K16A), with copper ions. Similar to ETC cupredoxin plastocyanin, these assemblies contain copper sites with blue-shifted (λmax 573 nm) electronic transitions and strongly oxidizing reduction potentials. Electron spin echo envelope modulation and X-ray absorption spectroscopies define square planar Cu(II) sites containing a single His ligand. Restrained molecular dynamics of the cross-ß peptide bilayer architecture support metal ion coordination stabilizing the leaflet interface and indicate that the relatively high reduction potential is not simply the result of distorted coordination geometry (entasis). Cyclic voltammetry (CV) supports a charge-hopping mechanism across multiple copper centers placed 10-12 Å apart within the assembled peptide leaflet interface. This metal-templated scaffold accordingly captures the electron shuttle and cupredoxin functionality in a peptide membrane-localized electron transport chain.

2.
Org Biomol Chem ; 22(21): 4243-4248, 2024 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-38712975

RESUMO

Protamine-mediated micellar aggregates, featuring an AIE-based fluorescent sensor, facilitate efficient detection of trypsin activity. This method enables the detection of trypsin at exceptionally low concentrations (0.01-0.1 µg mL-1) in urine, demonstrating its potential for early clinical diagnosis of trypsin-related pancreatic diseases.


Assuntos
Corantes Fluorescentes , Micelas , Pancreatopatias , Tripsina , Tripsina/metabolismo , Tripsina/urina , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Humanos , Pancreatopatias/diagnóstico , Espectrometria de Fluorescência , Protaminas/análise
3.
J Obstet Gynaecol Res ; 48(1): 244-250, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34729873

RESUMO

A 35-year-old woman presented with abdominal discomfort at 26 weeks gestation. The magnetic resonance imaging demonstrated a huge unilocular cystic mass with mural nodules originated from body and tail of pancreas. There was also a cystic mass in the left ovary with suppressed intensity on fat saturated image. One week later, she complained of worsening left lower abdominal pain and dyspnea as a new symptom. Hence, distal pancreatectomy with splenectomy and left ovarian cystectomy were performed. The huge cystic mass of pancreas was compressing the diaphragm, and left tubo-ovarian torsion was observed. This is the second case wherein an MCN of the pancreas with mature cystic teratoma of the ovary caused different symptoms. The management of MCNs in pregnant women should consider multiple aspects such as the malignancy potential of imaging findings, severity of symptoms, and fetal well-being.


Assuntos
Neoplasias Ovarianas , Neoplasias Pancreáticas , Complicações Neoplásicas na Gravidez , Adulto , Feminino , Humanos , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico por imagem , Complicações Neoplásicas na Gravidez/cirurgia , Esplenectomia
4.
Small ; 17(4): e2004988, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33369864

RESUMO

High-sensitivity detection of minute quantities or concentration variations of analytes of clinical importance is critical for biosensing to ensure accurate disease diagnostics and reliable health monitoring. A variety of sensitivity-improving concepts have been proposed from chemical, physical, and biological perspectives. In this review, elements that are responsible for sensitivity enhancement are classified and discussed in accordance with their operating steps in a typical biosensing workflow that runs through sampling, analyte recognition, and signal transduction. With a focus on optical biosensing, exemplary sensitivity-improving strategies are introduced, which can be developed into "plug-and-play" modules for many current and future sensors, and discuss their mechanisms to enhance biosensing performance. Three major strategies are covered: i) amplification of signal transduction by polymerization and nanocatalysts, ii) diffusion-limit-breaking systems for enhancing sensor-analyte contact and subsequent analyte recognition by fluid-mixing and analyte-concentrating, and iii) combined approaches that utilize renal concentration at the sampling and recognition steps and chemical signal amplification at the signal transduction step.


Assuntos
Técnicas Biossensoriais , Polimerização
5.
J Obstet Gynaecol Res ; 47(5): 1917-1921, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33650156

RESUMO

A 78-year-old woman with the chief complaint of vaginal bleeding was referred to our institution. Pelvic magnetic resonance imaging showed a 2.1 cm × 2.0 cm soft tissue mass in the left vaginal area with left inguinal lymph node enlargement. A positron emission tomography/computer tomography scan showed a focal hypermetabolic lesion in the left vaginal area with involvement of vulvar area. Pelvic examination showed a vaginal wall mass and the patient underwent surgical excision of the mass. The results of pathology indicated lymphoepithelioma-like carcinoma (LELC) in the vagina. The patient was admitted subsequently in the oncological department for additional chemoradiation treatment. LELC is extremely rare in the vagina, and only three cases have been reported in the literature. Here we report an extremely rare case of this tumor and review of the previous literature.


Assuntos
Carcinoma de Células Escamosas , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Vagina/cirurgia
6.
Nano Lett ; 20(10): 7020-7027, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32667815

RESUMO

Molecular binding in surface-based biosensing is inherently governed by diffusional transport of molecules in solution to surface-immobilized counterparts. Optothermally generated surface microbubbles can quickly accumulate solutes at the bubble-liquid-substrate interface due to high-velocity fluid flows. Despite its potential as a concentrator, however, the incorporation of bubbles into protein-based sensing is limited by high temperatures. Here, we report a biphasic liquid system, capable of generating microbubbles at a low optical power/temperature by formulating PFP as a volatile, water-immiscible component in the aqueous host. We further exploited zwitterionic surface modification to prevent unwanted printing during bubble generation. In a single protein-protein interaction model, surface binding of dispersed proteins to capture proteins was enhanced by 1 order of magnitude within 1 min by bubbles, compared to that from static incubation for 30 min. Our proof-of-concept study exploiting fluid formulation and optothermal add-on paves an effective way toward improving the performances of sensors and spectroscopies.


Assuntos
Microbolhas , Difusão , Temperatura
7.
J Vasc Interv Radiol ; 30(9): 1351-1360.e1, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31101417

RESUMO

PURPOSE: This study compared changes in imaging and in pain relief between patients with intraosseous, as opposed to extraosseous bone metastases. Both groups were treated palliatively with magnetic resonance-guided high-intensity-focused ultrasound (MRgHIFU). MATERIALS AND METHODS: A total of 21 patients were treated prospectively with MRgHIFU at 3 centers. Intraprocedural thermal changes measured using proton resonance frequency shift (PRFS) thermometry and gadolinium-enhanced T1-weighted (Gd-T1W) image appearances after treatment were compared for intra- and extraosseous metastases. Pain scores and use of analgesic therapy documented before and up to 90 days after treatment were used to classify responses and were compared between the intra- and extraosseous groups. Gd-T1W changes were compared between responders and nonresponders in each group. RESULTS: Thermal dose volumes were significantly larger in the extraosseous group (P = 0.039). Tumor diameter did not change after treatment in either group. At day 30, Gd-T1W images showed focal nonenhancement in 7 of 9 patients with intraosseous tumors; in patients with extraosseous tumors, changes were heterogeneous. Cohort reductions in worst-pain scores were seen for both groups, but differences from baseline at days 14, 30, 60, and 90 were only significant for the intraosseous group (P = 0.027, P = 0.013, P = 0.012, and P = 0.027, respectively). By day 30, 67% of patients (6 of 9) with intraosseous tumors were classified as responders, and the rate was 33% (4 of 12) for patients with extraosseous tumors. In neither group was pain response indicated by nonenhancement on Gd-T1W. CONCLUSIONS: Intraosseous tumors showed focal nonenhancement by day 30, and patients had better pain response to MRgHIFU than those with extraosseous tumors. In this small cohort, post-treatment imaging was not informative of treatment efficacy.


Assuntos
Neoplasias Ósseas/terapia , Tratamento por Ondas de Choque Extracorpóreas , Imagem por Ressonância Magnética Intervencionista , Dor Musculoesquelética/etiologia , Cuidados Paliativos , Adulto , Idoso , Analgésicos/uso terapêutico , Neoplasias Ósseas/complicações , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Europa (Continente) , Tratamento por Ondas de Choque Extracorpóreas/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Musculoesquelética/diagnóstico , Dor Musculoesquelética/tratamento farmacológico , Medição da Dor , Valor Preditivo dos Testes , Estudos Prospectivos , Seul , Fatores de Tempo , Resultado do Tratamento
8.
Biochem Biophys Res Commun ; 495(2): 2004-2009, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29253572

RESUMO

Secretory clusterin (sCLU) is a stress-associated protein that confers resistance to therapy when overexpressed. In this study, we observed that the V-ATPase inhibitors bafilomycin A1 and concanamycin A significantly stimulated sCLU protein expression. Knockdown of sCLU with siRNA sensitized non-small cell lung cancer (NSCLC) cells to bafilomycin A1, suggesting that sCLU expression renders cells resistant to V-ATPase inhibitors. The dual PI3K/AKT and mTOR inhibitor BEZ235 suppressed sCLU expression and enhanced cell sensitivity induced by bafilomycin A1. Notably, sCLU knockdown further decreased the expression of the survivin protein by bafilomycin A1, and the ectopic expression of survivin alleviated the cell sensitivity by bafilomycin A1 and sCLU depletion, suggesting that increased sensitivity to sCLU depletion in the cells with V-ATPase inhibitors is due, at least in part, to the down-regulation of survivin. Taken together, we demonstrated that the depletion of sCLU expression enhances the sensitivity of NSCLC cells to V-ATPase inhibitors by decreasing survivin expression. Inhibition of the PI3K/AKT/mTOR pathway enhances the sensitivity of NSCLC cells to V-ATPase inhibitors, leading to decreased sCLU and survivin expression. Thus, we suggest that a combination of PI3K/AKT/mTOR inhibitors with V-ATPase inhibitors might be an effective approach for NSCLC treatment.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/terapia , Clusterina/genética , Terapia Genética/métodos , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias Pulmonares/terapia , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidores , Células A549 , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada/métodos , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Inativação Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Survivina
9.
J Magn Reson Imaging ; 46(2): 354-364, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28067975

RESUMO

PURPOSE: To evaluate magnetization-prepared 3D T2 -weighted magnetic resonance imaging (MRI) measurements of acute tissue changes produced during ablative MR high-intensity focused ultrasound (MR-HIFU) exposures. MATERIALS AND METHODS: A clinical MR-HIFU system (3T) was used to generate thermal lesions (n = 24) in the skeletal muscles of three pigs. T1 -weighted, 2D T2 -weighted, and magnetization-prepared 3D T2 -weighted sequences were acquired before and after therapy to evaluate tissue changes following ablation. Tissues were harvested shortly after imaging, fixed in formalin, and gross-sectioned. Select lesions were processed into whole-mount sections. Lesion dimensions for each imaging sequence (length, width) and for gross sections (diameter of lesion core and rim) were assessed by three physicists. Contrast-to-background ratio between lesions and surrounding muscle was compared. RESULTS: Lesion dimensions on T1 and 2D T2 -weighted imaging sequences were well correlated (R2 ∼0.7). The contrast-to-background ratio between lesion and surrounding muscle was 7.4 ± 2.4 for the magnetization-prepared sequence versus 1.7 ± 0.5 for a conventional 2D T2 -weighted acquisition, and 7.0 ± 2.9 for a contrast-enhanced T1 -weighted sequence. Compared with diameter measured on gross pathology, all imaging sequences overestimated the lesion core by 22-33%, and underestimated the lesion rim by 6-13%. CONCLUSION: After MR-HIFU exposures, measurements of the acute thermal damage patterns in muscle using a magnetization-prepared 3D T2 -weighted imaging sequence correlate with 2D T2 -weighted and contrast-enhanced T1 -weighted imaging, and all agree well with histology. The magnetization-prepared sequence offers positive tissue contrast and does not require IV contrast agents, and may provide a noninvasive imaging evaluation of the region of acute thermal injury at multiple times during HIFU procedures. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:354-364.


Assuntos
Tratamento por Ondas de Choque Extracorpóreas , Imageamento por Ressonância Magnética , Músculo Esquelético/diagnóstico por imagem , Animais , Cateterismo , Meios de Contraste , Feminino , Temperatura Alta , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Necrose , Oxigênio , Razão Sinal-Ruído , Suínos
10.
Eur Radiol ; 27(9): 3956-3965, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28210800

RESUMO

OBJECTIVE: To evaluate the integrity of endometrial enhancement after magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) ablation of submucosal uterine fibroids based on contrast-enhanced MRI findings, and to identify the risk factors for endometrial impairment. METHODS: In total, 117 submucosal fibroids (diameter: 5.9 ± 3.0 cm) in 101 women (age: 43.6 ± 4.4 years) treated with MR-HIFU ablation were retrospectively analysed. Endometrial integrity was assessed with contrast-enhanced T1-weighted images at immediate (n = 101), 3-month (n = 62) and 12-month (n = 15) follow-ups. Endometrial impairment was classified into grades 0 (continuous endometrium), 1 (pin-point, full-thickness discontinuity), 2 (between grade 1 and 3), or 3 (full-thickness discontinuity >1 cm). Risk factors were assessed with generalized estimating equation (GEE) analysis. RESULTS: Among 117 fibroids, grades 0, 1, 2 and 3 endometrial impairments were observed at initial examination in 56.4%, 24.8%, 13.7% and 4.3%, respectively. Among 37 fibroid cases of endometrial impairment for which follow-ups were conducted, 30 showed improvements at 3- and/or 12-month follow-up. GEE analysis revealed the degree of endometrial protrusion was significantly associated with severity of endometrial injury (P < 0.0001). CONCLUSIONS: After MR-HIFU ablation of submucosal fibroids, endometrial enhancement was preserved intact or minimally impaired in most cases. Impaired endometrium, which is more common after treating endometrially-protruded fibroids, may recover spontaneously. KEY POINTS: • After MR-HIFU ablation for submucosal fibroid, endometrium is mostly preserved/minimally impaired. • Endometrial-protruded submucosal fibroid is susceptible to more severe endometrial impairment. • The impaired endometrium may recover spontaneously at follow-up MR exams.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Leiomioma/cirurgia , Neoplasias Uterinas/cirurgia , Adulto , Endométrio/cirurgia , Feminino , Humanos , Aumento da Imagem/métodos , Leiomioma/patologia , Imageamento por Ressonância Magnética/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Estudos Retrospectivos , Cirurgia Assistida por Computador/métodos , Resultado do Tratamento , Neoplasias Uterinas/patologia
11.
Ann Nutr Metab ; 70(2): 122-131, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28346913

RESUMO

BACKGROUND/AIMS: Low socioeconomic status (SES) is linked to higher incidence/mortality of cardiovascular disease, but emerging evidence inconsistently reported that education level, a proxy for SES, is related to cardiovascular risk and metabolic syndrome (MetS) in Koreans. Furthermore, limited information is available on whether dietary components would mediate the relationship between education level and cardiovascular risk. We hypothesized that selected food consumption mediates the association between education level and MetS prevalence. METHODS: Data from the Korea National Health and Nutritional Examination Survey (2008-2011) were included in cross-sectional analyses (n = 11,029, 30-64 years). The possible mediating effect of selected food groups (fruits, raw vegetables, red meat, milk, and soft drinks) on the association between education level and MetS was tested using a multiple mediation model. RESULTS: Education level was negatively associated with MetS prevalence. The association between lower education level and higher MetS prevalence was partially mediated by selected food consumption (lower intakes of fruit, red meat and milk; higher intakes of vegetable and soft drink) after adjusted for covariates. Gender also modified the association between education level and MetS prevalence that was more prominent in women than in men. CONCLUSIONS: Selected food consumption substantially contributes to the association between education level and MetS in Korean adults, especially among women.


Assuntos
Povo Asiático , Doenças Cardiovasculares/epidemiologia , Dieta , Escolaridade , Síndrome Metabólica/epidemiologia , Adulto , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Prevalência , República da Coreia , Fatores de Risco
12.
Acta Radiol ; 58(7): 778-785, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27903759

RESUMO

Background Intrahepatic distant recurrence (IDR) after radiofrequency (RF) ablation for hepatocellular carcinoma (HCC) is associated with poor overall survival outcome. Purpose To evaluate the incidence and findings on pre-procedural gadoxetic acid-enhanced liver magnetic resonance imaging (MRI) of precursor nodules for IDR after RF ablation for HCC. Material and Methods This study was approved by our institutional review board. Among 343 patients treated with RF ablation for HCC between 2009 and 2011, 141 patients who underwent pre-procedural gadoxetic acid-enhanced liver MRI and experienced IDR were enrolled. The presence of precursor nodules for IDR on pre-procedural imaging was assessed. Nodules were categorized based on hypervascularity in the arterial phase and signal intensity on hepatobiliary phase images. Time to recurrence was compared between patients with and without precursor nodules. Results In 46 (32.7%) of 141 patients (50 HCCs), there were precursor nodules on pre-procedural MRIs (median follow-up period, 4.39 years; range, 0.08-6.08). In three patients, HCCs were missed on imaging. In the remaining 43 patients, the 47 precursor nodules identified were non-hypervascular hypointense (n = 26), non-hypervascular isointense (n = 6), non-hypervascular hyperintense (n = 2), hypervascular hypointense (n = 10), and hypervascular isointense (n = 3). The mean time-to-recurrence was significantly shorter for patients with precursor nodules than for those without (16.6 versus 24.0 months, P = 0.011). Conclusion About one-third of patients with IDR after RF ablation for HCC had precursor nodules on pre-procedural gadoxetic acid-enhanced MRI, most commonly non-hypervascular hypointense nodules in the hepatobiliary phase.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Ablação por Cateter , Meios de Contraste , Gadolínio DTPA , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
J Stroke Cerebrovasc Dis ; 26(8): 1766-1772, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28456464

RESUMO

BACKGROUND: One of the major, and most harmful, symptoms of dysphagia in stroke survivors is aspiration. Survivors of unilateral cortical strokes with dysphagia and resulting aspiration have been reported to have greater initiation delays in laryngeal closure than those who did not aspirate. Few studies have reported such data in survivors of subcortical stroke. METHODS: This study measured initiation of laryngeal closure (ILC) and laryngeal closure duration (LCD) in 2 groups of subjects: 15 stroke survivors with cortical lesions and 15 stroke survivors with subcortical lesions. Means and standard deviations of ILC and LCD were analyzed on 5-mL thin liquid and 5-mL puree boluses using a 100-ms timer during subsequent analysis of videofluoroscopic swallowing examinations. Statistical comparisons were used by repeated measures analysis of variance. Significance level was set at P < .05. RESULTS: ILC was significantly longer in stroke survivors with a subcortical lesion than in those with a cortical lesion for both bolus consistencies. However, there were no significant differences between the 2 groups in LCD. Stroke survivors with a subcortical lesion had a greater incidence of penetration or aspiration and silent aspiration than those with a cortical lesion and a longer delay in the ILC. CONCLUSIONS: Subcortical lesions may put these survivors at greater risk of aspiration due to delayed initial laryngeal closure and reduced oral and laryngeal sensation. The subcortical damage, which occurs at the basal ganglia, may interrupt the ILC.


Assuntos
Infarto Cerebral/complicações , Transtornos de Deglutição/etiologia , Deglutição , Laringe/fisiopatologia , Aspiração Respiratória de Conteúdos Gástricos/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/fisiopatologia , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/fisiopatologia , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Aspiração Respiratória de Conteúdos Gástricos/diagnóstico , Aspiração Respiratória de Conteúdos Gástricos/fisiopatologia , Fatores de Risco , Fatores de Tempo , Gravação em Vídeo
14.
Adv Funct Mater ; 26(39): 7057-7066, 2016 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-29081729

RESUMO

Theranostic photonic nanoparticles (TPNs) that cross the blood-brain barrier (BBB) and efficiently deliver a therapeutic agent to treat brain diseases, simultaneously providing optical tracking of drug delivery and release, are introduced. These TPNs are constructed by physical encapsulation of visible and/or near-infrared photonic molecules, in an ultrasmall micellar structure (<15 nm). Phytochemical curcumin is employed as a therapeutic as well as visible-emitting photonic component. In vitro BBB model studies and animal imaging, as well as ex vivo examination, reveal that these TPNs are capable of transmigration across the BBB and subsequent accumulation near the orthotopic xenograft of glioblastoma multiforme (GBM) that is the most common and aggressive brain tumor whose vasculature retains permeability-resistant properties. The intracranial delivery and release of curcumin can be visualized by imaging fluorescence produced by energy transfer from curcumin as the donor to the near-infrared emitting dye, coloaded in TPN, where curcumin induced apoptosis of glioma cells. At an extremely low dose of TPN, a significant therapeutic outcome against GBM is demonstrated noninvasively by bioluminescence monitoring of time-lapse proliferation of luciferase-expressing U-87 MG human GBM in the brain. This approach of TPN can be generally applied to a broad range of brain diseases.

15.
Radiology ; 278(3): 925-35, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26313526

RESUMO

PURPOSE: To evaluate the relationships between T2 signal intensity and semiquantitative perfusion magnetic resonance (MR) parameters of uterine fibroids in patients who were screened for MR-guided high-intensity focused ultrasound (HIFU) ablation. MATERIALS AND METHODS: Institutional review board approval was granted, and informed consents were waived. One hundred seventy most symptom-relevant, nondegenerated uterine fibroids (mean diameter, 7.3 cm; range, 3.0-17.2 cm) in 170 women (mean age, 43.5 years; range, 24-56 years) undergoing screening MR examinations for MR-guided HIFU ablation from October 2009 to April 2014 were retrospectively analyzed. Fibroid signal intensity was assessed as the ratio of the fibroid T2 signal intensity to that of skeletal muscle. Parameters of semiquantitative perfusion MR imaging obtained during screening MR examination (peak enhancement, percentage of relative peak enhancement, time to peak [in seconds], wash-in rate [per seconds], and washout rate [per seconds]) were investigated to assess their relationships with T2 signal ratio by using multiple linear regression analysis. Correlations between T2 signal intensity and independently significant perfusion parameters were then evaluated according to fibroid type by using Spearman correlation test. RESULTS: Multiple linear regression analysis revealed that relative peak enhancement showed an independently significant correlation with T2 signal ratio (Β = 0.004, P < .001). Submucosal intracavitary (n = 20, ρ = 0.275, P = .240) and type III (n = 18, ρ = 0.082, P = .748) fibroids failed to show significant correlations between perfusion and T2 signal intensity, while significant correlations were found for all other fibroid types (ρ = 0.411-0.629, P < .05). CONCLUSION: In possible candidates for MR-guided HIFU ablation, the T2 signal intensity of nondegenerated uterine fibroids showed an independently significant positive correlation with relative peak enhancement in most cases, except those of submucosal intracavitary or type III fibroids.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma/patologia , Leiomioma/cirurgia , Imagem por Ressonância Magnética Intervencionista , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
Radiology ; 280(1): 300-12, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26824711

RESUMO

Purpose To compare the long-term therapeutic outcomes of radiofrequency (RF) ablation for hepatocellular carcinoma (HCC) in subcapsular versus nonsubcapsular locations by using propensity score matching. Materials and Methods RF ablation for subcapsular HCC is controversial because of a high risk of incomplete ablation or major complications. This retrospective study was approved by the institutional review board, and the requirement for informed consent was waived. Between April 2006 and December 2011, 508 consecutive patients (396 men, 112 women; age range, 30-80 years) with a single HCC (Barcelona Clinic Liver Cancer stage 0 or A) underwent ultrasonography-guided percutaneous RF ablation as a first-line treatment. The patients were divided into two groups according to tumor location: subcapsular (n = 227) and nonsubcapsular (n = 281). Subcapsular HCC was defined as an index tumor located within 0.1 cm of the liver capsule. The association of subcapsular location and therapeutic outcomes of RF ablation was evaluated, including (a) local tumor progression (LTP) by using a competing risk regression model and (b) overall survival (OS) by using a Cox proportional hazards model according to propensity score matched data. The major complication rates from both overall data and matched data were assessed. Results Matching yielded 163 matched pairs of patients. In the two matched groups, cumulative LTP rates were 18.8% and 20.9% at 3 and 5 years, respectively, in the subcapsular group and 13.2% and 16.0% in the nonsubcapsular group. Corresponding OS rates were 90.7% for 3 years and 83.2% for 5 years in the subcapsular group and 91.4% and 79.1%, respectively, in the nonsubcapsular group. Hazard ratios (HRs) for LTP (HR = 1.37, P = .244) and OS (HR = 0.86, P = .604) were not significantly different between the two matched groups. Additionally, differences in major complication rates were not significant between groups for the two sets of data (P > .05). Conclusion The differences in LTP, OS, and major complication rates of RF ablation for HCC were not significant between subcapsular and nonsubcapsular groups. (©) RSNA, 2016.


Assuntos
Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/métodos , Neoplasias Hepáticas/cirurgia , Pontuação de Propensão , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção
17.
Opt Lett ; 41(13): 2923-6, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27367066

RESUMO

We present a congestion estimation technique (CET) to estimate the optical network unit (ONU) registration success ratio for the ONU registration process in passive optical networks. An optical line terminal (OLT) estimates the number of collided ONUs via the proposed scheme during the serial number state. The OLT can obtain congestion level among ONUs to be registered such that this information may be exploited to change the size of a quiet window to decrease the collision probability. We verified the efficiency of the proposed method through simulation and experimental results.

18.
Mol Pharm ; 13(5): 1528-39, 2016 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-26998616

RESUMO

Monitoring of drug release from a heat-activated liposome carrier provides an opportunity for real-time control of drug delivery and allows prediction of the therapeutic effect. We have developed short-chain elastin-like polypeptide-incorporating thermosensitive liposomes (STLs). Here, we report the development of STL encapsulating gadobenate dimeglumine (Gd-BOPTA), a MRI contrast agent, and doxorubicin (Dox) (Gd-Dox-STL). The Dox release profile from Gd-Dox-STL was comparable to Gd-Dox-LTSL; however, the serum stability of Gd-Dox-STL was much higher than Gd-Dox-LTSL. MRI studies showed that the difference in T1 relaxation time between 37 and 42 °C for Gd-Dox-STL was larger than the difference for Gd-Dox-LTSL. Although relaxivity for both liposomes at 42 °C was similar, the relaxivity of Gd-Dox-STL at 37 °C was 2.5-fold lower than that of Gd-Dox-LTSL. This was likely due to Gd-BOPTA leakage from the LTSL because of low stability at 37 °C. Pharmacokinetic studies showed plasma half-lives of 4.85 and 1.95 h for Gd-Dox-STL and Gd-Dox-LTSL, respectively, consistent with in vitro stability data. In vivo MRI experiments demonstrated corelease of Dox and Gd-BOPTA from STL under mild hyperthermia induced by high-intensity focused ultrasound (HIFU), which suggests STL is a promising tumor selective formulation when coupled with MR-guided HIFU.


Assuntos
Antineoplásicos/administração & dosagem , Lipossomos/administração & dosagem , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Meios de Contraste/administração & dosagem , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/fisiologia , Elastina/administração & dosagem , Meia-Vida , Temperatura Alta , Hipertermia Induzida/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Meglumina/administração & dosagem , Meglumina/análogos & derivados , Meglumina/farmacocinética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/farmacocinética , Peptídeos/administração & dosagem , Temperatura , Ultrassonografia/métodos
19.
Langmuir ; 32(14): 3348-53, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27018461

RESUMO

Perfluorinated ligand-passivated Fe3O4 nanocrystals were prepared through a biphasic ligand exchange method. It was found that dissolved oxygen in the reaction media predominantly determined the degree of ligand exchange and the resultant dispersion property of nanocrystals in a fluorous solvent. X-ray photoelectron spectroscopic analyses revealed that dissolved oxygen molecules bind to the surface iron species of nanocrystals in competition with the carboxylate moiety of ligands during the exchange reaction, lowering the degree of ligand exchange and colloidal stability significantly. Reducing the oxygen content of the fluorous phase by N2 bubbling was found to result in a highly stable dispersion of phase-transferred Fe3O4 nanocrystals with a single-particle size distribution maintained for a few months.

20.
Liver Int ; 36(4): 580-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26503910

RESUMO

BACKGROUND & AIMS: We investigated whether pre- or post-ablation serum alpha-foetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP) levels can predict prognosis in patients with curative radiofrequency ablation (RFA) for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). METHODS: We retrospectively analysed 412 patients with HBV-related single HCC treated with percutaneous RFA between January 2004 and December 2013. AFP and DCP levels were measured before (pre-ablation) and 1 month after treatment (post-ablation). We assessed predictive factors for overall and recurrence-free survival. RESULTS: On univariate analysis, Child-Pugh score, Model for End-Stage Liver Disease (MELD) score, platelet count, tumour size, Barcelona Clinic Liver Cancer (BCLC) stage, and pre- and post-ablation DCP were significant for overall survival; and age, Child-Pugh score, MELD score, platelet count, tumour size, Cancer of the Liver Italian Program (CLIP) score, BCLC stage, and pre- and post-ablation AFP and DCP were significant for recurrence-free survival. Multivariate analysis revealed significant differences in overall survival by MELD score and tumour size and in recurrence-free survival by BCLC stage. Among the tumour markers, post-ablation DCP was an independent prognostic factor for overall and recurrence-free survival [hazard ratio (HR), 3.438; 95% confidence interval (CI), 1.331-8.877; P = 0.011 and HR, 4.934; 95% CI, 2.761-8.816; P < 0.001 respectively]. Post-ablation AFP was associated with recurrence-free survival (HR, 1.995; 95% CI, 1.476-2.697; P < 0.001) but not overall survival. CONCLUSIONS: In patients with HBV-related HCC, post-ablation serum DCP is a useful biomarker for predicting survival and recurrence after curative RFA.


Assuntos
Biomarcadores Tumorais/sangue , Biomarcadores/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/cirurgia , Hepatite B/complicações , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/cirurgia , Precursores de Proteínas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/mortalidade , Intervalo Livre de Doença , Feminino , Hepatite B/diagnóstico , Hepatite B/mortalidade , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Protrombina , República da Coreia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , alfa-Fetoproteínas/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA