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1.
Clin Cardiol ; 44(1): 78-84, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33205849

RESUMO

BACKGROUND: Cryoballoon ablation (CBA) and radiofrequency ablation (RFA) are the most common procedures used to treat refractory atrial fibrillation (AF) and are performed through pulmonary vein isolation (PVI). Studies have shown that CBA can approximately match the therapeutic effects of RFA against AF. However, few studies have investigated the difference between CBA and RFA of the effects on left atrial remodeling for paroxysmal AF. OBJECTIVE: Atrial remodeling is considered pivotal to the occurrence and development of AF, therefore we sought to assess the influence of atrial remodeling in patients with paroxysmal AF after CBA and RFA in this study. METHODS: In this nonrandomized retrospective observational study, we enrolled 328 consecutive patients who underwent CBA or RFA for refractory paroxysmal AF in May 2014 to May 2017 in our hospital. After propensity score matching, 96 patients were included in the CBA group, and 96 were included in the RFA group. Patients were asked to undergo a 12-lead electrocardiogram, a 24-h Holter monitor, and an echocardiogram and to provide their clinical history and symptoms at 6 months and 1, 2, and 3 years postprocedurally. Electrical remodeling of the left atrium was assessed by P wave dispersion (Pdis); structural remodeling was assessed by the left atrium diameter (LAD) and left atrial volume index (LAVI) during scheduled visits. RESULTS: As of January 2020, compared with baseline, at 1 year, 2 years, and 3 years after ablation, the average changes in Pdis (∆Pdis), LAD (∆LAD), and LAVI (∆LAVI) were significant in both the CBA and RFA groups. Six months after ablation, ∆Pdis, ∆LAD, and ∆LAVI were greater in the CBA group than in the RFA group. There was no significant difference between the two groups in AF/flutter recurrence, but the AF/flutter-free survival time of CBA group may be longer than RFA group after 2 years after ablation. A higher ∆Pdis, ∆LAD, or ∆LAVI at 1 year after ablation may increase AF/flutter-free survival. CONCLUSIONS: Although CBA and RFA are both effective in left atrial electrical and structural reverse-remodeling in paroxysmal AF, CBA may outperform RFA for both purposes 6 months after ablation. However, during long-term follow-up, there was no significant intergroup difference.

2.
Magn Reson Med ; 85(1): 346-356, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32726485

RESUMO

PURPOSE: To explore the value of MRI texture analysis in evaluating the presence and severity of early renal ischemia-reperfusion injury (IRI). METHODS: Healthy New Zealand rabbits were used (IRI group, N = 54; control group, N = 8). Rabbits in the IRI group underwent left renal artery clamping for 60 minutes. Magnetic resonance imaging was performed before and at 1, 12, 24, and 48 hours after IRI. The relationship between MRI texture features and histopathology parameters was assessed using Pearson's correlation coefficients. The diagnostic performance of texture features in kidney differentiation at different time points was assessed by receiver operating characteristic curve analysis. RESULTS: T2 WI_S(3,-3)Inverse_Difference_Moment had the strongest correlation with brush border destruction, tubular epithelial edema, necrosis, and cast (r = 0.56, -0.58, 0.62, and 0.69, respectively; all P < .001). BOLD_S(4,-4)Correlation had the strongest correlation with interstitial inflammatory cell infiltration (r = 0.63, P < .001). SWI_S(4,4)Difference_Entropy had the strongest correlation with microvessel density (r = 0.61, P < .001). The areas under the curve for T2 WI_S(3,-3)Inverse_Difference_Moment, SWI_S(4,4)Difference_Entropy, and BOLD_S(4,-4)Correlation in kidney differentiation before IRI and that at 1 and 12 hours after reperfusion were 0.76, 0.72, and 0.70, respectively; the values before IRI and at 24 and 48 hours after reperfusion were 0.84, 0.81, and 0.69, respectively. The area under the curve for T2 WI_S(3,-3)Inverse_Difference_Moment in kidney differentiation at 1 and 12 hours after reperfusion and that at 24 and 48 hours after reperfusion was 0.66. CONCLUSION: Magnetic resonance imaging texture analysis can be used for evaluating the presence and severity of early renal IRI.

3.
Acta Radiol ; : 284185120951964, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867506

RESUMO

BACKGROUND: The Fuhrman nuclear grade system is one of the most important independent indicators in patients with clear cell renal cell carcinoma (ccRCC) for aggressiveness and prognosis. Preoperative assessment of tumor aggressiveness is important for surgical decision-making. PURPOSE: To explore the role of magnetic resonance imaging (MRI) texture analysis based on susceptibility-weighted imaging (SWI) in predicting Fuhrman grade of ccRCC. MATERIAL AND METHODS: A total of 45 patients with SWI and surgically proven ccRCC were divided into two groups: the low-grade group (Fuhrman I/II, n = 29) and the high-grade group (Fuhrman III/IV, n = 16). Texture features were extracted from SWI images. Feature selection was performed, and multivariable logistic regression analysis was performed to develop the SWI-based texture model for grading ccRCCs. Receiver operating characteristic (ROC) curve analysis and leave-group-out cross-validation (LGOCV) were performed to test the reliability of the model. RESULTS: A total of 396 SWI-based texture features were extracted from each SWI image. The SWI-based texture model developed by multivariable logistic regression analysis was: SWIscore = -0.59 + 1.60 * ZonePercentage. The area under the ROC curve of the SWI-based texture model for differentiating high-grade ccRCC from low-grade ccRCC was 0.81 (95% confidence interval 0.67-0.94), with 80% accuracy, 56.25% sensitivity, and 93.10% specificity. After 100 LGOCVs, the mean accuracy, sensitivity, and specificity were 90.91%, 91.83%, and 89.89% for the training sets, and 77.29%, 80.52%, and 71.44% for the test sets, respectively. CONCLUSION: SWI-based texture analysis might be a reliable quantitative approach for differentiating high-grade ccRCC from low-grade ccRCC.

4.
Sensors (Basel) ; 20(19)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32992878

RESUMO

Water-soluble chemicals, involving a wide range of toxic chemicals in aqueous solutions, remain essential in both daily living or industrial uses. However, most toxicants are evaporated with water through their use and thus cause deleterious effects on the domestic environment and health in humans. Unfortunately, most current low-dose chemical vapor detection technologies are restricted by the use of sophisticated instruments and unable to promptly detect the quantity of diverse toxicants in a single analysis. To address these issues, this study reports the development of simple and fast chemical vapor detection using doctor-blade-coated macroporous poly(2-hydroxyethyl methacrylate)/poly(ethoxylated trimethylolpropane triacrylate) photonic crystals, in which the poly(2-hydroxyethyl methacrylate) has strong affinity to insecticide vapor owing to a favorable Gibbs free energy change for their mixing. The condensation of water-soluble chemical vapor therefore results in a significant reflection peak shift and an obvious color change. The visual colorimetric readout can be further improved by increasing the lattice spacing of the macroporous photonic crystals. Furthermore, the dependence of the reflection peak position on vapor pressure under actual conditions and the reproducibility of vapor detecting are also evaluated in this study.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32930454

RESUMO

Skin is the largest organ, with the functionalities of protection, regulation, and sensation. The emulation of human skin via flexible and stretchable electronics gives rise to electronic skin (e-skin), which has realized artificial sensation and other functions that cannot be achieved by conventional electronics. To date, tremendous progress has been made in data acquisition and transmission for e-skin systems, while the implementation of perception within systems, that is, sensory data processing, is still in its infancy. Integrating the perception functionality into a flexible and stretchable sensing system, namely artificial skin perception, is critical to endow current e-skin systems with higher intelligence. Here, recent progress in the design and fabrication of artificial skin perception devices and systems is summarized, and challenges and prospects are discussed. The strategies for implementing artificial skin perception utilize either conventional silicon-based circuits or novel flexible computing devices such as memristive devices and synaptic transistors, which enable artificial skin to surpass human skin, with a distributed, low-latency, and energy-efficient information-processing ability. In future, artificial skin perception would be a new enabling technology to construct next-generation intelligent electronic devices and systems for advanced applications, such as robotic surgery, rehabilitation, and prosthetics.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32767395

RESUMO

Simultaneous implementation of high signal-to-noise ratio (SNR) but low crosstalk is of great importance for weak surface electromyography (sEMG) signals when precisely driving a prosthesis to perform sophisticated activities. However, due to gaps with the curved skin during muscle contraction, many electrodes have poor compliance with skin and suffer from high bioelectrical impedance. This causes serious noise and error in the signals, especially the signals from low-level muscle contractions. Here, the design of a compliant electrode based on an adhesive hydrogel, alginate-polyacrylamide (Alg-PAAm) is reported, which eliminates those large gaps through the strong electrostatic interaction and abundant hydrogen bond with the skin. The obtained compliant electrode, having an ultralow bioelectrical impedance of ≈20 kΩ, can monitor even 2.1% maximal voluntary contraction (MVC) of muscle. Furthermore, benefiting from the high SNR of >5:1 at low-level MVC, the crosstalk from irrelevant muscle is minimized through reducing the electrode size. Finally, a prosthesis is successfully demonstrated to precisely grasp a needle based on a 9 mm2 Alg-PAAm compliant electrode. The strategy to design such compliant electrodes provides the potential for improving the quality of dynamically weak sEMG signals to precisely control prosthesis in performing purposefully dexterous activity.

8.
J Cardiothorac Surg ; 15(1): 207, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738925

RESUMO

BACKGROUND: Although lobectomy with mediastinal lymph node dissection (MLND) is the first option for early-stage non-small cell lung cancer (NSCLC) patients, the time trends of MLND in stage IA NSCLC patients who undergo a lobectomy are not clear still. METHODS: We included stage IA NSCLC patients who underwent lobectomy or lobectomy with MLND between 2003 and 2013 in the SEER database. The time trend of MLND was compared among patients who underwent a lobectomy. RESULTS: For stage T1a patients, the lobectomy group and lobectomy with MLND group had no differences in postoperative overall survival (OS) (P = 0.34) or lung-cancer specific survival (LCSS) (P = 0.18) between 2003 and 2013. For stage T1b patients, the OS (P = 0.01) and LCSS (P = 0.01) were different between the lobectomy group and the lobectomy with MLND group in the period from 2003 to 2009; however, only OS (P = 0.04), not LCSS (P = 0.14), was different between the lobectomy group and the lobectomy with MLND group between 2009 and 2013. For T1c patients, the OS (P = 0.01) and LCSS (P = 0.02) were different between the two groups between 2003 and 2009 but not between 2009 and 2013 (P = 0.60; P = 0.39). From the Cox regression analysis, we found that the factors affecting OS/LCSS in T1b and T1c patients were age, sex, year of diagnosis, histology, and grade, in which year of diagnosis was the obvious factor (HR = 0.79, CI = 0.71-0.87; HR = 0.73, CI = 0.64-0.84). CONCLUSIONS: There was a time trend in prognosis differences between the lobectomy group and lobectomy with MLND group for T1b and T1c stage NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Excisão de Linfonodo/tendências , Idoso , Carcinoma Pulmonar de Células não Pequenas/mortalidade , China/epidemiologia , Bases de Dados Factuais , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Excisão de Linfonodo/métodos , Linfonodos/patologia , Metástase Linfática , Masculino , Mediastino/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Programa de SEER , Análise de Sobrevida , Fatores de Tempo
9.
Chem Asian J ; 15(17): 2742-2748, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32658379

RESUMO

Although linker-free Au nanoparticle superstructures (AuNPSTs) have demonstrated to have satisfactory photothermal conversion efficiency owing to their enhanced visible-near-infrared absorption caused by the interparticle coupling, they cannot be used directly for in vivo photothermal therapy (PTT) of cancer because of poor stability. To address this issue, we herein propose a polymer-coating strategy, dressing AuNPST on a poly(dopamine) (PDA) coat, and successfully investigate the in vivo PTT effect of AuNPSTs. By employing Triton X-100 as an emulsifier for the formation of AuNPSTs, dopamine was site-specifically polymerized around each AuNPST by the interaction between -OH of Triton X-100 and -NH2 of dopamine. As-fabricated AuNPST/PDA has a sphere-like shape with an average diameter of ∼106 nm and the PDA shell is about 10 nm PDA thick. The AuNPST/PDA shows enhanced durability to heat, acid, and alkali compared with bare AuNPST. Also, under 808 nm laser irradiation, AuNPST/PDA shows photothermal conversion efficiency of ∼33%, higher than bare AuNPST (∼23%). Significantly, AuNPST/PDA can be used as in-vitro and in-vivo PTT agent and shows excellent therapeutic efficacy for tumor ablation thanks to its enhanced stability and biocompatibility, indicative of its potential practicability in clinical PTT.

10.
J Mater Chem B ; 8(45): 10346-10352, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32657318

RESUMO

One-dimensional (1D) morphology-unique Au-Ag2S nano-hybrids are achieved by combining the interfacial self-assembly of Ag nanowires, interface-oriented site-specific etching of Ag nanowires with AuCl4-, and the sulfurization of S2-. The as-formed Au-Ag2S nano-hybrid has a trough-like morphology. The wall of the Au-Ag2S nanotrough is a Ag2S/Au/Ag2S trilayer wall, but the Ag2S layer is a Ag2S-rich mixture of Ag2S and Au rather than pure Ag2S because of the diffusion of Au atoms towards Ag2S. The Au-Ag2S nanotrough shows strong absorption in the visible region (400-800 nm) and exhibits a favorable photoelectrochemical (PEC) response, the photocurrent of which is ∼8.5 times larger than that of pure Ag2S. This enhanced PEC response originates from the localized plasmonic resonance effect of Au. Moreover, the PEC biosensor based on the Au-Ag2S nanotroughs shows high sensitivity and selectivity, satisfactory reproducibility, and good stability towards human α-thrombin (TB) detection: a sensitive linear response ranging from 1.00 to 10.00 pmol L-1 and a low detection limit of 0.67 pmol L-1. This study provides a new model for studying the PEC behavior of plasmonic metal/semiconductor materials, and this Au-Ag2S nanotrough may also be useful in the fields of photocatalysis and photovoltaics.

11.
J Food Prot ; 83(12): 2102-2106, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32663262

RESUMO

Salmonella, a bacterial foodborne pathogen, can contaminate meat, milk, and vegetables. While appropriate measures are available to control Salmonella, the inhibitory phytochemicals from plants are gaining increased attention. Punicalagin, a natural antimicrobial, is one of the main active tannins isolated from Punica granatum L. To obtain a broader understanding of the effect of punicalagin on the cell membranes of Salmonella Typhimurium, the growth curves, extracellular potassium concentration, release of cell constituents, intracellular pH, membrane potential, and morphological features were characterized to elucidate the mechanisms of action. Treatment with punicalagin induced an increase in the extracellular concentrations of potassium and a release of cell constituents. A higher pH gradient, an increase in the intracellular pH, and cell membrane depolarization were observed after punicalagin treatment. Electron microscopy observations showed that the cell membrane structures of Salmonella Typhimurium were damaged by punicalagin. It is concluded that punicalagin inhibits the proliferation of Salmonella Typhimurium and destroys the integrity of the cell membrane, leading to a loss of cell homeostasis. These findings indicate that punicalagin has the potential to be developed as a future alternative to control Salmonella Typhimurium contamination in foods and reduce the risk of salmonellosis.

12.
Zhongguo Fei Ai Za Zhi ; 23(6): 509-513, 2020 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-32517457

RESUMO

BACKGROUND: After general thoracic surgery, a chest tube is usually placed for closed drainage to expel gas accumulation in the thoracic cavity and fluid accumulation to promote lung re-expansion. It can also be observed whether there is active bleeding after the operation and whether there is a pulmonary leak. The conventional drainage of the chest cavity is connected with a water-sealed drainage bottle, and the patient condition is judged by observing the drainage situation and the fluctuation of the water column, which is a very classic method. However, the water-sealed bottle has the disadvantages of being easy to overturn and inconvenient to carry, which is not conducive to the early activities of patients. Under the concept of accelerated rehabilitation, our center applied a new type of anhydrous thorax negative pressure drainage device and achieved good results. The purpose of this study was to observe the effect of a new type of anhydrous thoracic negative pressure drainage device in patients after thoracic surgery. METHODS: Retrospective analysis of patients who underwent lung surgery in the First Affiliated Hospital of Zhejiang University Medical College from January 2018 to December 2019, patients were divided into two groups. One group of patients used a traditional closed-chest drainage water-sealed bottle as a control group, and the other group used a new type of anhydrous negative-pressure drainage bottle as an experimental group. Patients' gender, age, hypertension, diabetes, smoking history, surgical incisions and surgical methods, and the length of hospital stay and postoperative hospital stay were calculated. RESULTS: There were no statistical differences in age, gender, comorbidities (hypertension, diabetes, smoking history), scope of surgery, and duration of surgery between the two groups of patients, but there were statistical differences in surgical incisions between the two groups of patients (P=0.01). We found that patients using the new waterless negative pressure drainage device were shorter than patients with water negative pressure drainage device in terms of postoperative hospital stay and total hospitalization time, and the difference was statistically significant (P=0.02, P=0.04). CONCLUSIONS: The new type of anhydrous thoracic negative pressure drainage device has a good effect on the rapid recovery and advancement after thoracic surgery.

13.
Nat Commun ; 11(1): 2183, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366821

RESUMO

Coupling myoelectric and mechanical signals during voluntary muscle contraction is paramount in human-machine interactions. Spatiotemporal differences in the two signals intrinsically arise from the muscular excitation-contraction process; however, current methods fail to deliver local electromechanical coupling of the process. Here we present the locally coupled electromechanical interface based on a quadra-layered ionotronic hybrid (named as CoupOn) that mimics the transmembrane cytoadhesion architecture. CoupOn simultaneously monitors mechanical strains with a gauge factor of ~34 and surface electromyogram with a signal-to-noise ratio of 32.2 dB. The resolved excitation-contraction signatures of forearm flexor muscles can recognize flexions of different fingers, hand grips of varying strength, and nervous and metabolic muscle fatigue. The orthogonal correlation of hand grip strength with speed is further exploited to manipulate robotic hands for recapitulating corresponding gesture dynamics. It can be envisioned that such locally coupled electromechanical interfaces would endow cyber-human interactions with unprecedented robustness and dexterity.


Assuntos
Eletromiografia/métodos , Força da Mão/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Amplitude de Movimento Articular/fisiologia , Membros Artificiais , Bioengenharia/instrumentação , Bioengenharia/métodos , Fenômenos Biomecânicos , Eletrônica Médica/instrumentação , Eletrônica Médica/métodos , Dedos/fisiologia , Antebraço/fisiologia , Mãos/fisiologia , Humanos , Desenho de Prótese/instrumentação , Desenho de Prótese/métodos
14.
Artigo em Inglês | MEDLINE | ID: mdl-32374473

RESUMO

On-skin flexible devices provide a noninvasive approach for continuous and real-time acquisition of biological signals from the skin, which is essential for future chronic disease diagnosis and smart health monitoring. Great progress has been achieved in flexible devices to resolve the mechanical mismatching between conventional rigid devices and human skin. However, common materials used for flexible devices including silicon-based elastomers and various metals exhibit no resistance to epidermal surface lipids (skin oil and grease), which restricts the long-term and household usability. Herein, an on-skin electrode with anti-epidermal-surface-lipid function is reported, which is based on the grafting of a zwitterionic poly(2-methacryl-oyloxyethyl, methacryloyl-oxyethyl, or meth-acryloyloxyethyl phosphorylcholine) (PMPC) brush on top of gold-coated poly(dimethylsiloxane) (Au/PDMS). Such an electrode allows the skin-lipids-fouled surface to be cleaned by simple water rinsing owing to the superhydrophilic zwitterionic groups. As a proof-of-concept, the PMPC-Au/PDMS electrodes are employed for both electrocardiography (ECG) and electromyography (EMG) recording. The electrodes are able to maintain stable skin-electrode impedance and good signal-to noise ratio (SNR) by water rinsing alone. This work provides a material-based solution to improve the long-term reusability of on-skin electronics and offers a unique prospective on developing next generation wearable healthcare devices.

15.
Nat Commun ; 11(1): 1332, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32165612

RESUMO

Compared to transmission systems based on shafts and gears, tendon-driven systems offer a simpler and more dexterous way to transmit actuation force in robotic hands. However, current tendon fibers have low toughness and suffer from large friction, limiting the further development of tendon-driven robotic hands. Here, we report a super tough electro-tendon based on spider silk which has a toughness of 420 MJ/m3 and conductivity of 1,077 S/cm. The electro-tendon, mechanically toughened by single-wall carbon nanotubes (SWCNTs) and electrically enhanced by PEDOT:PSS, can withstand more than 40,000 bending-stretching cycles without changes in conductivity. Because the electro-tendon can simultaneously transmit signals and force from the sensing and actuating systems, we use it to replace the single functional tendon in humanoid robotic hand to perform grasping functions without additional wiring and circuit components. This material is expected to pave the way for the development of robots and various applications in advanced manufacturing and engineering.


Assuntos
Condutividade Elétrica , Seda/química , Aranhas/química , Tendões/fisiologia , Animais , Simulação por Computador , Retroalimentação , Humanos , Teste de Materiais , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Impressão Tridimensional , Robótica , Seda/ultraestrutura
16.
Environ Sci Pollut Res Int ; 27(13): 15337-15349, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32077017

RESUMO

A novel catalyst of Fe-Mn/AC was prepared and used as a heterogeneous catalyst to activate O3/Na2S2O8 for landfill leachate biochemical effluent treatment. The experimental results indicated that the highest COD (84%) and color (98%) removal was obtained at Fe-Mn/AC dosage 1.2 g/L, O3 concentration 1.2 g/L, Na2S2O8 dosage 6 g/L, initial pH 10, and reaction time 100 min. Three-dimensional and excitation emission matrix (3D-EEM) fluorescence spectrometry, Fourier transform infrared spectroscopy (FTIR), and gas chromatography mass spectrometry (GC/MS) of wastewater samples before and after treatment demonstrated that the leachate biochemical effluent contained a large amount of humic and fulvic acid organic compounds. After treatment with this coupling system, both the pollution level of dissolved organic matter (DOM) and the fluorescence intensity declined. The micro morphology of Fe-Mn/AC was characterized using scanning X-ray diffraction patterns (XRD), electron microscope spectra (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy. It can be concluded that the microscopic morphology of the catalyst is porous. The main active components are amorphous MnO2 and multivalent iron oxides. Furthermore, the Fe-Mn/AC catalyst showed great reusability; the removal efficiency of COD was only reduced from 84% to 79% at the fourth reaction. Moreover, the COD removal efficiency could recover to 81% after catalyst regeneration.


Assuntos
Águas Residuárias , Poluentes Químicos da Água/análise , Compostos de Manganês , Compostos Orgânicos , Oxirredução , Óxidos
17.
Chem Commun (Camb) ; 56(20): 3011-3014, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32048641

RESUMO

An efficient novel visible-light photoredox-catalyzed dual carbon-carbon bond cleavage of methylenecyclopropanes and cycloketone oximes for the synthesis of 2-cyanoalkylsulfonated 3,4-dihydronaphthalenes through the insertion of sulfur dioxide is established. This dual cleavage of carbon-carbon bonds involves a radical pathway and goes through a sequence of iminyl radical formation, carbon-carbon bond cleavage, sulfur dioxide insertion, sulfonyl radical addition, another carbon-carbon bond cleavage, and intramolecular cyclization.

18.
Cytotherapy ; 22(1): 6-15, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32005355

RESUMO

PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths with high recurrence after surgery due to a paucity of effective post-surgical adjuvant treatments. DC vaccines can activate multiple anti-tumor immune responses but have not been explored for post-surgery PDAC recurrence. Intraperitoneal (IP) delivery may allow increased DC vaccine dosage and migration to lymph nodes. Here, we investigated the role of prophylactic DC vaccination controlling PDAC tumor growth with IP delivery as an administration route for DC vaccination. METHODS: DC vaccines were generated using ex vivo differentiation and maturation of bone marrow-derived precursors. Twenty mice were divided into four groups (n = 5) and treated with DC vaccines, unpulsed mature DCs, Panc02 lysates or no treatment. After tumor induction, mice underwent three magnetic resonance imaging scans to track tumor growth. Apparent diffusion coefficient (ADC), a quantitative magnetic resonance imaging measurement of tumor microstructure, was calculated. Survival was tracked. Tumor tissue was collected after death and stained with hematoxylin and eosin, Masson's trichrome, terminal deoxynucleotidyl transferase dUTP nick end labeling and anti-CD8 stains for histology. RESULTS: DC-vaccinated mice demonstrated stronger anti-tumor cytotoxicity compared with control groups on lactate dehydrogenase assay. DC vaccine mice also demonstrated decreased tumor volume, prolonged survival and increased ΔADC compared with control groups. On histology, the DC vaccine group had increased apoptosis, increased CD8+ T cells and decreased collagen. ΔADC negatively correlated with % collagen in tumor tissues. DISCUSSION: Prophylactic DC vaccination may inhibit PDAC tumor growth during recurrence and prolong survival. ΔADC may be a potential imaging biomarker that correlates with tumor histological features.


Assuntos
Vacinas Anticâncer/imunologia , Carcinoma Ductal Pancreático/terapia , Células Dendríticas/imunologia , Células Dendríticas/transplante , Neoplasias Pancreáticas/terapia , Adenocarcinoma/terapia , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Linfonodos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Recidiva Local de Neoplasia/prevenção & controle , Vacinação
19.
Acad Radiol ; 27(12): 1727-1733, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32033861

RESUMO

RATIONALE AND OBJECTIVES: To investigate whether transcatheter intraarterial perfusion (TRIP) magnetic resonance imaging (MRI) can differentiate reversible electroporation (RE) zones from irreversible electroporation (IRE) zones immediately after IRE procedure in the rabbit liver. MATERIALS AND METHODS: All studies were approved by the institutional animal care and use committee and performed in accordance with institutional guidelines. A total of 13 healthy New Zealand White rabbits were used. After selective catheterization of the hepatic artery under X-ray fluoroscopy, we acquired TRIP-MRI at 20 minutes post-IRE using 3 mL of 5% intraarterial gadopentetate dimeglumine. Semi-quantitative (peak enhancement, PE; time to peak, TTP; wash-in slope, WIS; areas under the time-intensity curve, AUT, over 30, 60, 90, 120, 150, and 180 seconds after the initiation of enhancement) and quantitative (Ktrans, ve, and vp) TRIP-MRI parameters were calculated. The relationships between TRIP-MRI parameters and histological measurements and the differential ability of TRIP-MRI parameters was assessed. RESULTS: PE, AUT60, AUT90, AUT120, AUT150, AUT180, Ktrans, and ve were significantly higher in RE zones than in IRE zones (all P < 0.05), and AUC for these parameters ranged from 0.91(95% CI, 0.80, 1.00) to 0.99 (95% CI, 0.98, 1.00). There was no significant difference in AUC between any two parameters (Z, 0-1.47; P, 0.14-1.00). Hepatocyte apoptosis strongly correlated with PE, AUT60, AUT90, AUT120, AUT150, AUT180, Ktrans, and vp (the absolute value r, 0.6-0.7, all P < 0.0001). CONCLUSION: AUT150 or AUT180 could be a potential imaging biomarker to differentiate RE from IRE zones, and TRIP-MRI permits to differentiate RE from IRE zones immediately after IRE procedure in the rabbit liver.


Assuntos
Neoplasias Hepáticas , Angiografia por Ressonância Magnética , Animais , Gadolínio DTPA , Artéria Hepática/diagnóstico por imagem , Coelhos
20.
Chem Commun (Camb) ; 56(13): 1976-1979, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-31960850

RESUMO

We herein used Ag2Se quantum dots (QDs) as a target-modulated sensitizer for upconversion nanoparticles (UCNPs) and the target thrombin as the sensitizing switch to construct a biosensor, circumventing the limited luminescence resonance energy transfer (LRET) efficiency of UCNPs, with enhanced signal-to-background ratio (SBR) and assay sensitivity.


Assuntos
Técnicas Biossensoriais/métodos , Raios Infravermelhos , Pontos Quânticos/química , Trombina/análise , Transferência Ressonante de Energia de Fluorescência , Humanos , Limite de Detecção , Razão Sinal-Ruído
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