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1.
Nature ; 586(7829): 385-389, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33057219

RESUMO

The visualization of accurate colour information using quantum dots has been explored for decades, and commercial products employing environmentally friendly materials are currently available as backlights1. However, next-generation electroluminescent displays based on quantum dots require the development of an efficient and stable cadmium-free blue-light-emitting device, which has remained a challenge because of the inferior photophysical properties of blue-light-emitting materials2,3. Here we present the synthesis of ZnSe-based blue-light-emitting quantum dots with a quantum yield of unity. We found that hydrofluoric acid and zinc chloride additives are effective at enhancing luminescence efficiency by eliminating stacking faults in the ZnSe crystalline structure. In addition, chloride passivation through liquid or solid ligand exchange leads to slow radiative recombination, high thermal stability and efficient charge-transport properties. We constructed double quantum dot emitting layers with gradient chloride content in a light-emitting diode to facilitate hole transport, and the resulting device showed an efficiency at the theoretical limit, high brightness and long operational lifetime. We anticipate that our efficient and stable blue quantum dot light-emitting devices can facilitate the development of electroluminescent full-colour displays using quantum dots.

2.
Nano Lett ; 24(15): 4633-4640, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38568864

RESUMO

The glycerol oxidation reaction (GOR) run with photoelectrochemical cells (PECs) is one of the most promising ways to upgrade biomass because it is thermodynamically favorable, while irreversible overoxidation leads to unsatisfactory product selectivities. Herein, a tunable one-dimensional nanoconfined environment was introduced into the GOR process, which accelerated mass transfer of glycerol via the microscale fluid effect and changed the main oxidation product from formic acid (FA) to glyceraldehyde (GLD), which led to retention of the heavier multicarbon products. The rate of glycerol diffusion in the nanochannels increased by a factor of 4.92 with decreasing inner diameters. The main product from the PEC-selective oxidation of glycerol changed from the C1 product FA to the C3 product GLD with a great selectivity of 60.7%. This work provides a favorable approach for inhibiting further oxidation of multicarbon products and illustrates the importance of microenvironmental regulation in biomass oxidation.

3.
Small ; : e2402371, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597692

RESUMO

Quantum dot (QD) light-emitting diodes (QLEDs) are promising for next-generation displays, but suffer from carrier imbalance arising from lower hole injection compared to electron injection. A defect engineering strategy is reported to tackle transport limitations in nickel oxide-based inorganic hole-injection layers (HILs) and find that hole injection is able to enhance in high-performance InP QLEDs using the newly designed material. Through optoelectronic simulations, how the electronic properties of NiOx affect hole injection efficiency into an InP QD layer, finding that efficient hole injection depends on lowering the hole injection barrier and enhancing the acceptor density of NiOx is explored. Li doping and oxygen enriching are identified as effective strategies to control intrinsic and extrinsic defects in NiOx, thereby increasing acceptor density, as evidenced by density functional theory calculations and experimental validation. With fine-tuned inorganic HIL, InP QLEDs exhibit a luminance of 45 200 cd m-2 and an external quantum efficiency of 19.9%, surpassing previous inorganic HIL-based QLEDs. This study provides a path to designing inorganic materials for more efficient and sustainable lighting and display technologies.

4.
J Am Chem Soc ; 145(28): 15425-15434, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37427828

RESUMO

Lithium-oxygen batteries have the potential to become the most eminent solution for future energy storage with their theoretical energy density exceeding all existing batteries. However, the insulating and insoluble discharge product (lithium peroxide; Li2O2) impairs practical application. Conventional catalyst designs based on the electronic structure and interfacial charge transfer descriptors have not been able to overcome these limitations due to Li2O2. Herein, we revisit the role of heterogeneous catalysts as substrates to regulate Li2O2 growth and the formation of solid/solid reaction interfaces. We demonstrate that controlled solid/solid interfacial structure design is a critical performance parameter beyond the inherent electronic structure. In particular, the Cu2O substrate in this study induces a homogeneous deposition of Pd atoms, which leads to well-controlled growth of Li2O2 resolving mass and charge transport limits (i.e., the bottleneck of oxygen reduction/evolution reactions), thus improving reversibility, capacity, and durability of the cells by dissipating electrochemical and mechanical stress. We thus verified the essential role of solid/solid interfaces to regulate the nucleation and growth process of Li2O2 in lithium-oxygen batteries.

5.
J Am Chem Soc ; 145(11): 6428-6433, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36897963

RESUMO

Indium phosphide (InP) quantum dots have enabled light-emitting diodes (LEDs) that are heavy-metal-free, narrow in emission linewidth, and physically flexible. However, ZnO/ZnMgO, the electron-transporting layer (ETL) in high-performance red InP/ZnSe/ZnS LEDs, suffers from high defect densities, quenches luminescence when deposited on InP, and induces performance degradation that arises due to trap migration from the ETL to the InP emitting layer. We posited that the formation of Zn2+ traps on the outer ZnS shell, combined with sulfur and oxygen vacancy migration between ZnO/ZnMgO and InP, may account for this issue. We synthesized therefore a bifunctional ETL (CNT2T, 3',3'″,3'″″-(1,3,5-triazine-2,4,6-triyl)tris(([1,1'-biphenyl]-3-carbonitrile)) designed to passivate Zn2+ traps locally and in situ and to prevent vacancy migration between layers: the backbone of the small molecule ETL contains a triazine electron-withdrawing unit to ensure sufficient electron mobility (6 × 10-4 cm2 V-1 s-1), and the star-shaped structure with multiple cyano groups provides effective passivation of the ZnS surface. We report as a result red InP LEDs having an EQE of 15% and a luminance of over 12,000 cd m-2; this represents a record among organic-ETL-based red InP LEDs.

6.
Nature ; 550(7674): 87-91, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28980632

RESUMO

Medical X-ray imaging procedures require digital flat detectors operating at low doses to reduce radiation health risks. Solution-processed organic-inorganic hybrid perovskites have characteristics that make them good candidates for the photoconductive layer of such sensitive detectors. However, such detectors have not yet been built on thin-film transistor arrays because it has been difficult to prepare thick perovskite films (more than a few hundred micrometres) over large areas (a detector is typically 50 centimetres by 50 centimetres). We report here an all-solution-based (in contrast to conventional vacuum processing) synthetic route to producing printable polycrystalline perovskites with sharply faceted large grains having morphologies and optoelectronic properties comparable to those of single crystals. High sensitivities of up to 11 microcoulombs per air KERMA of milligray per square centimetre (µC mGyair-1 cm-2) are achieved under irradiation with a 100-kilovolt bremsstrahlung source, which are at least one order of magnitude higher than the sensitivities achieved with currently used amorphous selenium or thallium-doped cesium iodide detectors. We demonstrate X-ray imaging in a conventional thin-film transistor substrate by embedding an 830-micrometre-thick perovskite film and an additional two interlayers of polymer/perovskite composites to provide conformal interfaces between perovskite films and electrodes that control dark currents and temporal charge carrier transportation. Such an all-solution-based perovskite detector could enable low-dose X-ray imaging, and could also be used in photoconductive devices for radiation imaging, sensing and energy harvesting.


Assuntos
Compostos de Cálcio/química , Óxidos/química , Impressão , Doses de Radiação , Radiografia/instrumentação , Radiografia/métodos , Titânio/química , Raios X , Césio/química , Eletrodos , Desenho de Equipamento , Iodetos/química , Imagens de Fantasmas , Selênio/química , Tálio/química , Transistores Eletrônicos
7.
Chin J Cancer Res ; 35(6): 660-674, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38204442

RESUMO

Objective: While a rushed operation can omit essential procedures, prolonged operative time results in higher morbidity. Nevertheless, the optimal operative time range remains uncertain. This study aimed to estimate the ideal operative time range and evaluate its applicability in laparoscopic cancer surgery. Methods: A prospectively collected multicenter database of 397 patients who underwent laparoscopic distal gastrectomy were retrospectively reviewed. The ideal operative time range was statistically calculated by separately analyzing the operative time of uneventful surgeries. Finally, intraoperative and postoperative outcomes were compared among the shorter, ideal, and longer operative time groups. Results: The statistically calculated ideal operative time was 135.4-165.4 min. The longer operative time (LOT) group had a lower rate of uneventful, perfect surgery than the ideal or shorter operative time (IOT/SOT) group (2.8% vs. 8.8% and 2.2% vs. 13.4%, all P<0.05). Longer operative time increased bleeding, postoperative morbidities, and delayed diet and discharge (all P<0.05). Particularly, an uneventful, perfect surgery could not be achieved when the operative time exceeded 240 min. Regardless of ideal time range, SOT group achieved the highest percentage of uneventful surgery (13.4%), which was possible by surgeon's ability to retrieve a higher number of lymph nodes and perform ≥150 gastrectomies annually. Conclusions: Operative time longer than the ideal time range (especially ≥240 min) should be avoided. If the essential operative procedure were faithfully conducted without compromising oncological safety, an operative time shorter than the ideal range leaded to a better prognosis. Efforts to minimize operative time should be attempted with sufficient surgical experience.

8.
J Am Chem Soc ; 144(45): 20923-20930, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36327099

RESUMO

InP-based quantum dot (QD) light-emitting diodes (QLEDs) provide a heavy-metal-free route to size-tuned LEDs having high efficiency. The stability of QLEDs may be enhanced by replacing organic hole-injection layers (HILs) with inorganic layers. However, inorganic HILs reported to date suffer from inefficient hole injection, the result of their shallow work functions. Here, we investigate the tuning of the work function of nickel oxide (NiOx) HILs using self-assembled molecules (SAMs). Density functional theory simulations and near-edge X-ray absorption fine structure put a particular focus onto the molecular orientation of the SAMs in tuning the work function of the NiOx HIL. We find that orientation plays an even stronger role than does the underlying molecular dipole itself: SAMs having the strongest electron-withdrawing nitro group (NO2), despite having a high intrinsic dipole, show limited work function tuning, something we assign to their orientation parallel to the NiOx surface. We further find that the NO2 group─which delocalizes electrons over the molecule by resonance─induces a deep lowest unoccupied molecular orbital level that accepts electrons from QDs, producing luminescence quenching. In contrast, SAMs containing a trifluoromethyl group exhibit an angled orientation relative to the NiOx surface, better activating hole injection into the active layer without inducing luminescence quenching. We report an external quantum efficiency (EQE) of 18.8%─the highest EQE among inorganic HIL-based QLEDs (including Cd-based QDs)─in InP QLEDs employing inorganic HILs.

9.
Nano Lett ; 21(12): 5247-5253, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34100618

RESUMO

In heterogeneous catalysts, metal-oxide interactions occur spontaneously but often in an undesired way leading to the oxidation of metal nanoparticles. Manipulating such interactions to produce highly active surface of metal nanoparticles can warrant the optimal catalytic activity but has not been established to date. Here we report that a prior reduced TiO2 support can reverse the interaction with Pt nanoparticles and augment the metallic state of Pt, exhibiting a 3-fold increase in hydrogen production rate compared to that of conventional Pt/TiO2. Spatially resolved electron energy loss spectroscopy of the Ti valence state and the electron density distribution within Pt nanoparticles provide direct evidence supporting that the Pt/TiO2/H2O triple junctions are the most active catalytic sites for water reduction. Our reverse metal-oxide interaction scheme provides a breakthrough in the stagnated hydrogen production efficiency and can be applied to other heterogeneous catalyst systems composed of metal nanoparticles with reducible oxide supports.


Assuntos
Nanopartículas Metálicas , Água , Catálise , Óxidos , Titânio
10.
BMC Cancer ; 18(1): 73, 2018 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-29329569

RESUMO

BACKGROUND: Greater lymph node retrieval in gastric cancer improves staging accuracy and may improve survival from increased clearance of nodal micrometastasis. This retrospective cohort study investigated if more lymph nodes removed in gastric cancer increases survival and if such effect is stage-specific due to differential risks of nodal micrometastasis and systemic disease. METHODS: The prospectively collected database of curatively resected gastric cancer patients in National Cancer Center, South Korea between 2000 and 2009 was reviewed. Disease-free survival (DFS) and overall survival (OS) for all patients and for each stage according to number of lymph nodes examined (1-30, 31-45, > 45) were analyzed. RESULTS: Of 4049 patients, 96.6% and 98.4% underwent D2 (perigastric and extragastric) lymphadenectomy and had ≥ 15 lymph nodes examined. Mean number of nodes examined was 43. Five-year OS & DFS rates were 83.3% and 80.7%. Patients with > 45 nodes examined had significantly lower DFS (p = 0.002) and OS (p = 0.007) compared to those with 1-30 and 31-45 nodes. However, proportion of patients with > 45 nodes examined increased with stage (p = 0.0005). Per stage, there was no significant difference in DFS and OS according to number of nodes examined except for stage IIIA favoring more nodes (p = 0.018 and p = 0.044, respectively). Similar trend was seen in stage IIB. Number of examined nodes positively correlated with number of pathologic nodes for all patients (r = 0.144, p < .001) but not for stage IIB and IIIA. Number of nodes examined was a significant survival predictor in stage IIIA. CONCLUSION: Greater lymph node harvest showed improved survival in intermediate-stage gastric cancer.


Assuntos
Adenocarcinoma/epidemiologia , Adenocarcinoma/cirurgia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/cirurgia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Gastrectomia , Humanos , Estimativa de Kaplan-Meier , Excisão de Linfonodo , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Micrometástase de Neoplasia , Prognóstico , República da Coreia/epidemiologia , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia
11.
Gastrointest Endosc ; 85(1): 155-163.e3, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27460389

RESUMO

BACKGROUND AND AIMS: Excellent long-term outcome is expected for early gastric cancers (EGCs) after endoscopic submucosal dissection (ESD). However, if ESD is considered noncurative at the pathologic evaluation, additional surgery is recommended. We evaluated whether long-term outcome is compromised if additional surgery is not performed for EGCs that are out-of-indication. METHODS: We retrospectively analyzed a cohort of patients with EGC not meeting ESD indications whose initial treatment was either ESD (n = 219) or surgery (n = 1799). Among them, 127 patients who underwent additional surgery after initial ESD and 67 patients who did not were matched using propensity scores to patients who initially underwent standard surgery, at a 1:1 ratio. Overall mortality and gastric cancer recurrence were compared. RESULTS: The overall mortality and gastric cancer recurrence rates were not significantly different between the 127 patients who underwent initial ESD with additional surgery and the corresponding initial standard surgery patients. However, the overall mortality of the 67 patients who underwent ESD without additional surgery (5-year mortality, 26.0%; 95% CI, 13.5%-49.9%) was higher than that of the matched initial standard surgery patients (5-year mortality, 14.5%; 95% CI, 6.3%-33.6%; P = .04). Gastric cancer recurrence was also higher in ESD patients without additional surgery (5-year recurrence, 17.0%; 95% CI, 7.6%-37.8%) than in the matched initial surgery group (0%; P = .002). In multivariate analyses, ESD without additional surgery was a significant risk factor for overall mortality and gastric cancer recurrence. CONCLUSIONS: Additional surgery should be encouraged after non-curative ESD to obtain long-term outcomes comparable with those of initial standard surgery. (Clinical trial registration number: NCC2015-0093.).


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Ressecção Endoscópica de Mucosa , Gastrectomia , Excisão de Linfonodo , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Adenocarcinoma/patologia , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Reoperação , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Resultado do Tratamento
12.
Nano Lett ; 16(3): 1840-7, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26885948

RESUMO

A vertically integrated junctionless field-effect transistor (VJ-FET), which is composed of vertically stacked multiple silicon nanowires (SiNWs) with a gate-all-around (GAA) structure, is demonstrated on a bulk silicon wafer for the first time. The proposed VJ-FET mitigates the issues of variability and fabrication complexity that are encountered in the vertically integrated multi-NW FET (VM-FET) based on an identical structure in which the VM-FET, as recently reported, harnesses a source and drain (S/D) junction for its operation and is thus based on the inversion mode. Variability is alleviated by bulk conduction in a junctionless FET (JL-FET), where current flows through the core of the SiNW, whereas it is not mitigated by surface conduction in an inversion mode FET (IM-FET), where current flows via the surface of the SiNW. The fabrication complexity is reduced by the inherent JL structure of the JL-FET because S/D formation is not required. In contrast, it is very difficult to dope the S/D when it is positioned at each floor of a tall SiNW with greater uniformity and with less damage to the crystalline structure of the SiNW in a VM-FET. Moreover, when the proposed VJ-FET is used as nonvolatile flash memory, the endurance and retention characteristics are improved due to the above-mentioned bulk conduction.

13.
J Gastroenterol Hepatol ; 31(2): 394-402, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26474082

RESUMO

BACKGROUND AND AIM: The aim of this study was to evaluate the validity of the parameters of conventional white-light endoscopy and magnifying endoscopy with narrow-band imaging (MENBI) for the prediction of discrepancies between pre- and post-resectional histology in cases of gastric adenoma with low-grade dysplasia (LGD) that were diagnosed based on endoscopically biopsied specimens. METHODS: The medical records of 266 lesions with gastric LGD that were diagnosed by endoscopic forceps biopsies were retrospectively reviewed. The Vienna classification was used for histologic diagnosis. These patients all underwent MENBI examinations followed by analyses of the incidence of histologic discrepancies and histologic heterogeneity. The relationship between white-light endoscopic/MENBI parameters and the presence of histologic discrepancies was also analyzed. RESULTS: Discrepancies between the pre- and post-resectional histologies were found in 74 cases (27.9%). Among those cases, the histology was upgraded in 71 cases, whereas the histology was downgraded in three cases. The presence of erythema and positive MENBI findings were independent factors for the prediction of upgraded histologic discrepancies (P-values = 0.008, < 0.001, respectively). A positive MENBI finding yielded the highest predictive value, with a multivariate adjusted odds ratio of 42.46. Histologic heterogeneity in post-resectional specimens was found in 40.8% of cases with upgraded histologic discrepancies. CONCLUSIONS: MENBI can provide more accurate information than white-light endoscopy for the prediction of pre- and post-resectional histologic discrepancies in biopsy-proven gastric LGD. Endoscopic resection is strongly recommended in cases with surface erythema on conventional white-light endoscopy or positive MENBI, irrespective of the lesion size.


Assuntos
Adenoma/patologia , Biópsia/métodos , Endoscopia Gastrointestinal/métodos , Mucosa Gástrica/patologia , Neoplasias Gástricas/patologia , Adenoma/diagnóstico , Idoso , Biópsia/instrumentação , Endoscopia Gastrointestinal/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias Gástricas/diagnóstico , Instrumentos Cirúrgicos
14.
Xenobiotica ; 45(1): 10-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25034008

RESUMO

1. Fimasartan is an angiotensin receptor II antagonist used to treat patients with hypertension. This drug is mainly excreted into bile as either the parent compound or a glucuronide conjugate. In this study, we examined the glucuronidation of fimasartan and characterized the UDP-glucuronosyltransferases (UGTs) responsible for the glucuronidation. 2. Only one type of fimasartan glucuronide was observed after incubation with pooled human liver microsomes (HLMs) and was identified as an N2-glucuronide based on comparison with an authentic standard. 3. Among the 12 UGT isoforms tested, UGT1A1, UGT1A3 and UGT2B7 showed catalytic activity toward fimasartan glucuronidation. The intrinsic clearance (CLint) of UGT1A3 was 68.5- and 21.4-fold higher than that of UGT1A1 and UGT2B7, respectively, and the estimated relative contribution of UGT1A3 in human liver was 94.1%. Both chemical inhibition and correlation studies demonstrated that fimasartan glucuronidation activity in HLMs was significantly related with UGT1A3 activity. Fimasartan glucuronide was identified as a substrate for P-glycoprotein (Pgp) and breast cancer response protein (BCRP). 4. These findings collectively indicate that UGT1A3 is the major UGT isoform responsible for the glucuronidation of fimasartan, and this glucuronide is excreted from hepatocytes via MDR1 and BCRP.


Assuntos
Antagonistas de Receptores de Angiotensina/metabolismo , Compostos de Bifenilo/metabolismo , Glucuronosiltransferase/metabolismo , Microssomos Hepáticos/enzimologia , Pirimidinas/metabolismo , Tetrazóis/metabolismo , Glucuronosiltransferase/antagonistas & inibidores , Humanos , Isoenzimas/metabolismo , Cinética
15.
World J Surg Oncol ; 13: 64, 2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25889520

RESUMO

BACKGROUND: FOLFOX-based adjuvant chemotherapy is a benefit for high-risk stage II and stage III colon cancer after curative resection. But, the prognostic factor or predictive marker for the efficacy of FOLFOX remains unclear. This study was aimed to identify the prognostic value and cumulative impact of adjuvant FOLFOX on the stage II and III colon cancer patients. METHODS: A total of 196 stage II and III colon cancer patients were retrospectively enrolled in prospectively collected data. They underwent curative resection followed by FOLFOX4 adjuvant chemotherapy. The oncological outcomes included the 5-year disease-free survival (DFS) rate and 5-year overall survival (OS) rate. Cox-regression analysis was performed to identify the prognostic value, and its cumulative impact was analyzed. RESULTS: The 5-year DFS rate of the patients was 71.94% and the 5-year OS rate was 81.5%. The prognostic values for the 5-year DFS rate and 5-year OS rate were T4 stage and preoperative anemia in a multivariate analysis. Each patient group who had no prognostic value, single, or both factors revealed 95.35%, 69.06%, and 28.57% in the 5-year DFS rate, respectively (p < 0.0001). The 5-year OS rate also showed the significant differences in each group who had no prognostic value, single, or both factors revealed 100%, 79.3%, and 45.92%, respectively (p < 0.0001). CONCLUSION: Our results showed similar efficacy to MOSAIC study in stage II and stage III colon cancer patients treated with adjuvant FOLFOX chemotherapy after curative resection. Patients who had T4 stage and/or preoperative anemia showed worse prognosis than patients without any prognostic value. These findings suggest that FOLFOX could not be effective in the patients with T4 stage colon cancer accompanied by preoperative anemia.


Assuntos
Anemia/fisiopatologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/mortalidade , Adenocarcinoma Mucinoso/tratamento farmacológico , Adenocarcinoma Mucinoso/mortalidade , Adenocarcinoma Mucinoso/patologia , Adulto , Idoso , Carcinoma de Células em Anel de Sinete/tratamento farmacológico , Carcinoma de Células em Anel de Sinete/mortalidade , Carcinoma de Células em Anel de Sinete/patologia , Neoplasias do Colo/patologia , Feminino , Fluoruracila/uso terapêutico , Seguimentos , Humanos , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Organoplatínicos/uso terapêutico , Cuidados Pré-Operatórios , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida
16.
Angew Chem Int Ed Engl ; 53(3): 771-4, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24307628

RESUMO

A carbon capture and use (CCU) strategy was applied to organic synthesis. Carbon dioxide (CO2) captured directly from exhaust gas was used for organic transformations as efficiently as hyper-pure CO2 gas from a commercial source, even for highly air- and moisture-sensitive reactions. The CO2 capturing aqueous ethanolamine solution could be recycled continuously without any diminished reaction efficiency.

17.
Nat Commun ; 15(1): 3586, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678023

RESUMO

Anode-free (or lithium-metal-free) batteries with garnet-type solid-state electrolytes are considered a promising path in the development of safe and high-energy-density batteries. However, their practical implementation has been hindered by the internal strain that arises from the repeated plating and stripping of lithium metal at the interlayer between the solid electrolyte and negative electrode. Herein, we utilize the titanium nitrate nanotube architecture and a silver-carbon interlayer to mitigate the anisotropic stress caused by the recurring formation of lithium deposition layers during the cycling process. The mixed ionic-electronic conducting nature of the titanium nitrate nanotubes effectively accommodates the entry of reduced Li into its free volume space via interfacial diffusion creep, achieving near-strain-free operation with nearly tenfold volume suppressing capability compared to a conventional Cu anode counterpart during the lithiation process. Notably, the fabricated Li6.4La3Zr1.7Ta0.3O12 (LLZTO)-based initial-anode-free quasi-solid-state battery full cell, coupled with an ionic liquid catholyte infused high voltage LiNi0.33Co0.33Mn0.33O2-based cathode with an areal capacity of 3.2 mA cm-2, exhibits remarkable room temperature (25 °C) cyclability of over 600 cycles at 1 mA cm-2 with an average coulombic efficiency of 99.8%.

18.
Trials ; 25(1): 7, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167216

RESUMO

BACKGROUND: Petersen's hernia, which occurs after Billroth-II (B-II) or Roux-en-Y (REY) anastomosis, can be reduced by defect closure. This study aims to compare the incidence of bowel obstruction above Clavien-Dindo classification grade III due to Petersen's hernia between the mesenteric fixation method and the conventional methods after laparoscopic or robotic gastrectomy. METHODS: This study was designed as prospective, single-blind, non-inferiority randomized controlled multicenter trial in Korea. Patients with histologically diagnosed gastric cancer of clinical stages I, II, or III who underwent B-II or REY anastomosis after laparoscopic or robotic gastrectomy are enrolled in this study. Participants who meet the inclusion criteria are randomly assigned to two groups: a CLOSURE group that underwent conventional Petersen's defect closure method and a MEFIX group that underwent the mesenteric fixation method. The primary endpoint is the number of patients who underwent surgery for bowel obstruction caused by Petersen's hernia within 3 years after laparoscopic or robotic gastrectomy. DISCUSSION: This trial is expected to provide high-level evidence showing that the MEFIX method can quickly and easily close Petersen's defect without increased postoperative complications compared to the conventional method. TRIAL REGISTRATION: ClinicalTrials.gov NCT05105360. Registered on November 3, 2021.


Assuntos
Derivação Gástrica , Hérnia Abdominal , Laparoscopia , Obesidade Mórbida , Humanos , Hérnia Abdominal/diagnóstico por imagem , Hérnia Abdominal/etiologia , Hérnia Abdominal/prevenção & controle , Estudos Prospectivos , Método Simples-Cego , Mesentério/cirurgia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Derivação Gástrica/efeitos adversos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Obesidade Mórbida/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
19.
Int J Surg ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38716987

RESUMO

BACKGROUNDS: Strong evidence is lacking as no confirmatory randomized controlled trials (RCTs) have compared the efficacy of totally laparoscopic distal gastrectomy (TLDG) with laparoscopy-assisted distal gastrectomy (LADG). We performed an RCT to confirm if TLDG is different from LADG. METHODS: The KLASS-07 trial is a multicentre, open-label, parallel-group, phase III, RCT of 442 patients with clinical stage I gastric cancer. Patients were enrolled from 21 cancer care centers in South Korea between January 2018 and September 2020 and randomized to undergo TLDG or LADG using blocked randomization with a 1:1 allocation ratio, stratified by the participating investigators. Patients were treated through R0 resections by TLDG or LADG as the full analysis set of the KLASS-07 trial. The primary endpoint was morbidity within postoperative day 30, and the secondary endpoint was QoL for 1 year. This trial is registered at ClinicalTrials.gov (NCT NCT03393182). RESULTS: 442 patients were randomized (222 to TLDG, 220 to LADG), and 422 patients were included in the pure analysis (213 and 209, respectively). The overall complication rate did not differ between the two groups (TLDG vs. LADG: 12.2% vs. 17.2%). However, TLDG provided less postoperative ileus and pulmonary complications than LADG (0.9% vs. 5.7%, P= 0.006; and 0.5% vs. 4.3%, P= 0.035, respectively). The QoL was better after TLDG than after LADG regarding emotional functioning at 6 months, pain at 3 months, anxiety at 3 and 6 months, and body image at 3 and 6 months (all P< 0.05). However, these QoL differences were resolved at 1 year. CONCLUSIONS: The KLASS-07 trial confirmed that TLDG is not different from LADG in terms of postoperative complication but has advantages to reduce ileus and pulmonary complications. TLDG can be a good option to offer better QoL in terms of pain, body image, emotion, and anxiety at 3-6 months.

20.
Int J Colorectal Dis ; 28(8): 1117-25, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23588871

RESUMO

BACKGROUND: Various types of adhesion barriers are widely used to prevent intra-abdominal adhesion. However, few studies have compared the efficacy of adhesion barriers using the same animal model. The aim of this study was to compare the anti-adhesive effects of various barrier agents using a newly developed, severe adhesion model. METHODS: A severe adhesion model was established by excision of a 1-cm(2) intra-abdominal wall and application of cyanoacrylate in rat. Eighty male Sprague-Dawley rats (10 weeks old; 370 ± 50 g) were divided randomly into four groups (n = 20 each): the untreated control group, G-group using a hyaluronic acid and sodium carboxymethyl cellulose gel (Guardix-sol®), A-group using 4% icodextrin (Adept®), and S-group using a hyaluronate-carboxymethyl cellulose membrane (Seprafilm®). The effect of each adhesion barrier was evaluated by means of the extent and severity of adhesion, difficulty of adhesiolysis scoring systems, and microscopic grade of fibrosis. RESULTS: The G-group showed no difference in adhesion score and fibrosis, the A-group demonstrated only a significantly lower fibrosis, and the S-group exhibited a significantly lower adhesion score and lower fibrosis compared with the control group. The S-group had a significantly lower adhesion score and reduced fibrosis compared with the G-group; however, no significant difference in adhesion score and fibrosis was noted with the A-group. CONCLUSIONS: The membranous barrier Seprafilm® may be effective in the prevention of adhesion in the condition of peritoneal injury combined with foreign material. Adept® showed a tendency of decreasing the severity of adhesion and was effective in the prevention of fibrosis.


Assuntos
Abdome/patologia , Materiais Biocompatíveis/uso terapêutico , Aderências Teciduais/tratamento farmacológico , Aderências Teciduais/prevenção & controle , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Aderências Teciduais/patologia
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