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1.
Environ Res ; 225: 115586, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36858303

RESUMO

In this study, the potential of petroleum sludge (PS) for hydrogen production via the gasification process was evaluated. For this purpose, nickel (Ni)-loaded ZSM-5 and γ-Al2O3 (Ni-ZS and Ni-Al) catalysts were prepared and employed for PS gasification in air condition. The effects of different supports, Ni loading content, and reaction temperatures on the production of hydrogen-rich syngas along with the stability and reusability of the best catalyst were investigated. Applying 5%Ni-ZS obtained more gas yield (68.09 wt%) and hydrogen selectivity (25.04 vol%) compared to those obtained by 5%Ni-Al mostly owing to weak metal-support interactions which led to the dominance of well-dispersed metallic Ni. At various Ni loading percentages, 10%Ni-ZS showed the highest catalytic efficiency, which increased both gas yield (70.92 wt%) and hydrogen selectivity (30.74 vol%). However, excessive Ni content (especially 20%) significantly reduced the gas yield and hydrogen selectivity because of limited accessibility of support's active sites, poor dispersion of Ni, and inappropriate acidity. Increasing the temperature promoted the gas yield and produced hydrogen, where the highest gas yield (73.18 wt%) and hydrogen selectivity (33.15 vol%) were obtained at 850 °C due to the endothermic nature of gasification reactions. The 10%Ni-ZS catalyst showed proper stability during three consecutive experiments at 850 °C. The spent catalyst was successfully regenerated without a significant reduction in activity or selectivity.


Assuntos
Níquel , Esgotos , Porosidade , Biomassa , Hidrogênio , Catálise
2.
Environ Res ; 224: 115553, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36822530

RESUMO

This study explored the potential of steam gasification of sewage sludge over different temperatures (non-catalytic) and bimetallic (Ni-Fe and Ni-Co) mesoporous Al-MCM48 (3-5% Al basis). The higher temperature (800 °C) resulted in higher gas yield (36.74 wt%) and syngas (H2 and CO) selectivity (35.30 vol% and 11.66 vol%). Moreover, catalytic approach displayed that the Al-MCM48 was effective support because the incorporation of nickel increased the efficiency of gasification reactions compared to HZSM-5 (30). It mainly comes from the presence of mesopores and higher surface area (710.05 m2/g) providing more reaction sites and higher stability (less coke formation). Furthermore, the addition of promoters such as Co and Fe allowed the formation of Ni-Fe and Ni-Co alloys, resulting in even higher gas yield and overall H2 and CO selectivity due to the promotion of related reactions such as tar cracking, Boudouard, water gas shift and reforming and so on. Ni-Co alloy catalyst (10% Ni-5% Co/Al-MCM48) resulted in the highest H2 (∼52 vol%) selectivity due to the enhanced Ni dispersion and synergy effect between Ni and Co. Moreover, the application of bi-metal alloy on Al-MCM48 showed no coke formation and significantly reduced CO2 and hydrocarbon selectivity in the product gas. Overall, this study presented a promising solution for sewage sludge disposal in terms of clean H2 generation, reduction in CO2 and higher stability of metal based catalysts at the same time.


Assuntos
Esgotos , Vapor , Dióxido de Carbono , Ligas , Hidrogênio
3.
Br J Surg ; 108(9): 1043-1049, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34487147

RESUMO

BACKGROUND: There remain concerns about the safety and functional benefit of laparoscopic pylorus-preserving gastrectomy (LPPG) compared with laparoscopic distal gastrectomy (LDG). This study evaluated short-term outcomes of a randomized clinical trial (RCT) comparing LPPG with LDG for gastric cancer. METHODS: The Korean Laparoendoscopic Gastrointestinal Surgery Study (KLASS)-04 trial was an investigator-initiated, open-label, parallel-assigned, superiority, multicentre RCT in Korea. Patients with cT1N0M0 cancer located in the middle third of the stomach at least 5 cm from the pylorus were randomized to undergo LPPG or LDG. Participants, care givers and those assessing the outcomes were not blinded to group assignment. Outcomes were 30-day postoperative morbidity rate and death at 90 days. RESULTS: Some 256 patients from nine institutions were randomized (LPPG 129 patients, LDG 127 patients) between July 2015 and July 2017 and outcomes for 253 patients were analysed. Postoperative complications within 30 days were seen in 19.3 and 15.5 per cent in the LPPG and LDG groups respectively (P = 0·419). Postoperative pyloric stenosis was observed in nine (7.2 per cent) and two (1·5 per cent) patients in the LPPG and LDG groups (P = 0·026) respectively. In multivariable analysis higher BMI was a risk factor for postoperative complications (odds ratio 1·17, 95 per cent c.i. 1·04 to 1·32; P = 0·011). Death at 90 days was zero in both groups. CONCLUSION: Postoperative complications and mortality was comparable in patients undergoing LPPG and LDG. Registration number: NCT02595086 (http://www.clinicaltrials.gov).


Assuntos
Gastrectomia/métodos , Laparoscopia/métodos , Estadiamento de Neoplasias/métodos , Piloro/cirurgia , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
4.
AJNR Am J Neuroradiol ; 42(6): 1099-1103, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33926897

RESUMO

BACKGROUND AND PURPOSE: The treatment paradigm for very large and giant aneurysms has recently changed to flow diversion, in light of the results of the Pipeline for Uncoilable or Failed Aneurysms trial. However, the effects of flow diversion were definitely unknown. We explored this topic and identified the predictors of such effects. MATERIALS AND METHODS: We retrospectively reviewed 51 patients with unruptured aneurysms admitted to our institution for flow diversion between February 2014 and August 2019. Patients were categorized into an effect group (no filling or remnant entry) and a no-effect group (subtotal or total filling). We evaluated the aneurysm size and shape, incorporation vessel, parent artery stenosis and curvature, stagnation of contrast medium within the aneurysm, use of balloon angioplasty, and intra-aneurysm thrombus as potential predictors of the effects of flow diversion. RESULTS: The effect group comprised 34 patients (66.7%, 34/51; no filling, 35.3%, 18/51; and remnant entry, 31.4%, 16/51). The no-effect group comprised 17 patients (33.3%, 17/51; subtotal filling, 29.4%, 15/51; and total filling, 3.9%, 2/51). An incorporation vessel and balloon angioplasty were independent risk factors for the no-effect group in multivariate logistic regression analyses (OR = 0.13 and 0.05; 95% confidence intervals, 0.02-0.62 and 0.00-0.32; P values, .021 and .004, respectively). CONCLUSIONS: Flow diversion is effective for very large and giant aneurysms, but the outcomes require further improvement. The results of this study show that an incorporated vessel and excessive balloon angioplasty might compromise flow diversion. This finding can help improve the outcomes of flow diversion.


Assuntos
Aneurisma Intracraniano , Embolização Terapêutica , Procedimentos Endovasculares , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Estudos Retrospectivos , Stents , Resultado do Tratamento
5.
Phys Med Biol ; 65(21): 215016, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-32736368

RESUMO

Dual-energy computed tomography (DECT) has shown a great potential for lowering range uncertainties, which is necessary for truly leveraging the Bragg peak in proton therapy. However, analytical stopping-power-ratio (SPR) estimation methods have limitations in resolving the influence from the beam-hardening artifact, i.e. CT number variation of the same object scanned under different imaging conditions, such as different patient size and location in the field-of-view (FOV). We present a convolutional neural network (CNN)-based framework to estimate proton SPR that accounts for patient geometry variation and addresses CT number variation. The proposed framework was tested on both prostate and head-and-neck (HN) patient datasets. Simulated CT images were used in order to have a well-defined ground-truth SPR for evaluation. Two training scenarios were evaluated: training with patient CT images (ideal scenario) and training with computational phantoms (realistic scenario). For the training in ideal scenario, computational phantoms were created based on 120 kVp patient CT images using a custom-defined density and material translation curve. Then, 80 kVp and 150 kVp Sn DECT image pairs were obtained using ray-tracing simulation, and their corresponding SPR was calculated from the known density and elemental compositions. For the training in realistic scenario, computational phantoms were created based on the geometry of calibration phantoms. For both scenarios, evaluation was performed on the phantoms created from patient CT images. Compared to a conventional parametric model, U-net trained with computational phantoms (realistic scenario) reduced the SPR estimation uncertainty (95th percentile) of the prostate patient from 1.10% to 0.71%, and HN patient from 2.11% to 1.20%. With the U-net trained with patient images (ideal scenario) uncertainty values were 0.32% and 0.42% for prostate and HN patients, respectively. These results suggest that CNN has great potential to improve the accuracy of SPR estimation in proton therapy by incorporating individual patient geometry information.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Prótons , Tomografia Computadorizada por Raios X , Calibragem , Estudos de Viabilidade , Humanos , Masculino , Imagens de Fantasmas , Neoplasias da Próstata/diagnóstico por imagem , Terapia com Prótons , Razão Sinal-Ruído , Incerteza
6.
Br J Surg ; 107(11): 1429-1439, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32492186

RESUMO

BACKGROUND: Sentinel node navigation surgery reduces the extent of gastric and lymph node dissection, and may improve quality of life. The benefit and harm of laparoscopic sentinel node navigation surgery (LSNNS) for early gastric cancer is unknown. The SENORITA (SEntinel Node ORIented Tailored Approach) trial investigated the pathological and surgical outcomes of LSNNS compared with laparoscopic standard gastrectomy (LSG) with lymph node dissection. METHODS: The SENORITA trial was an investigator-initiated, open-label, parallel-assigned, non-inferiority, multicentre RCT conducted in Korea. The primary endpoint was 3-year disease-free survival. The secondary endpoints, morbidity and mortality within 30 days of surgery, are reported in the present study. RESULTS: A total of 580 patients were randomized to LSG (292) or LSNNS (288). Surgery was undertaken in 527 patients (LSG 269, LSNNS 258). LSNNS could be performed according to the protocol in 245 of 258 patients, and a sentinel node basin was detected in 237 (96·7 per cent) Stomach-preserving surgery was carried out in 210 of 258 patients (81·4 per cent). Postoperative complications occurred in 51 patients in the LSG group (19·0 per cent) and 40 (15·5 per cent) in the LSNNS group (P = 0·294). Complications with a Clavien-Dindo grade of III or higher occurred in 16 (5·9 per cent) and 13 (5·0 per cent) patients in the LSG and LSNNS groups respectively (P = 0·647). CONCLUSION: The rate and severity of complications following LSNNS for early gastric cancer are comparable to those after LSG with lymph node dissection. Registration number: NCT01804998 ( http://www.clinicaltrials.gov).


ANTECEDENTES: La cirugía de navegación del ganglio centinela (sentinel node navigation surgery, SNNS) reduce la extensión de la resección gástrica y ganglionar, y puede mejorar la calidad de vida. Se desconoce el beneficio y el daño de la cirugía de navegación del ganglio centinela por vía laparoscópica (laparoscopic sentinel node navigation surgery, LSNNS) para el cáncer gástrico precoz. El ensayo clínico SENORITA investigó los resultados patológicos y quirúrgicos de LSNNS en comparación con la gastrectomía laparoscópica estándar (laparoscopic gastrectomy, LSG) con disección ganglionar (lymph node dissection, LND). MÉTODOS: El ensayo SENORITA fue un ensayo multicéntrico aleatorizado y controlado, iniciado por investigadores, abierto, con asignación a grupos paralelos y de no inferioridad llevado a cabo en Corea. El resultado primario fue la supervivencia libre de enfermedad a los 3 años. En el presente estudio, se describen los resultados secundarios correspondientes a morbilidad y mortalidad a los 30 días del postoperatorio. RESULTADOS: Un total de 580 pacientes fueron aleatorizados a LG (n = 292) o LSNNS (n = 288). La cirugía se realizó en 527 pacientes (LG 269, LSNNS 258). LSNNS pudo ser realizada de acuerdo con el protocolo en 245 de 258 pacientes y en 237 de 245 pacientes (96,7%) se detectó un ganglio centinela. La cirugía con preservación del estómago se realizó en 210 de 258 pacientes (81,4%). Las complicaciones postoperatorias se presentaron en 51 pacientes del grupo LSG (19,0%) y en 40 pacientes (15,5%) del grupo LSNNS (P = 0,294). Las complicaciones grado III o mayor de Clavien-Dindo se detectaron en 16 (5,9%) y 13 pacientes (5,0%) de los grupos LSG y LSNNS, respectivamente (P = 0,647). CONCLUSIÓN: El porcentaje y la gravedad de las complicaciones tras LSNNS para cancer gástrico precoz son comparables a la LSG con LND.


Assuntos
Adenocarcinoma/cirurgia , Gastrectomia/métodos , Laparoscopia/métodos , Excisão de Linfonodo/métodos , Linfonodo Sentinela/cirurgia , Neoplasias Gástricas/cirurgia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias/epidemiologia , Linfonodo Sentinela/patologia , Neoplasias Gástricas/patologia , Resultado do Tratamento
7.
J Hazard Mater ; 399: 123087, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32526438

RESUMO

The compound 1,4-dioxane (DO) irritates the eyes, skin, and mucous membrane and is classified as a carcinogen. In this study, the decomposition of DO by photocatalytic reaction using liquid phase plasma (LPP) with photocatalyst was suggested. Plasma was directly discharged as an aqueous DO solution to enhance photocatalytic decomposition activity. To increase the decomposition efficiency of DO by plasma, bismuth ferrite (BFO) prepared by a sol-gel method was introduced as a visible-light photocatalyst. In the application of LPP and BFO photocatalyst, the decomposition of DO by photocatalytic reaction was evaluated. BFO showed UV-vis diffusion reflectance spectroscopy results of absorption of UV and visible light over 600 nm, with a bandgap of approximately 2.2 eV. BFO showed visible light photochemical reaction characteristics to decompose particulate matter (PM) in the irradiation of 6 W visible light LED lamps. It seems that the narrow bandgap of BFO led to the photocatalytic activity in the visible light. In the decomposition reaction of DO with a photocatalyst and LPP, BFO showed better decomposition efficiency than TiO2. BFO can cause photocatalytic reactions in both UV and visible light in the case of LPP irradiation, which emits strong ultraviolet and visible light.

8.
Environ Res ; 187: 109632, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32454307

RESUMO

In this study, the kinetic analysis on the pyrolysis of a spent medicinal herb, namely spent Achyranthes root, is performed using a thermogravimetric analyzer and a model-free kinetic analysis method, allowing the calculation of activation energy values without the assumption of kinetic model. Owing to the structural change of lignin and elimination of hemicellulose during the decoction of raw Achyranthes root, the thermogravimetric analysis results show a large difference between the derivative thermogravimetry curves of spent and raw Achyranthes roots. The average apparent activation energy value of spent Achyranthes root, obtained from the non-isothermal thermogravimetric analysis, are found to be lower than those of raw Achyranthes root. This comes as a result of the much lower content of hemicellulose in spent Achyranthes root caused by the hemicellulose elimination from raw Achyranthes root during the decoction process. The catalytic fast pyrolysis of spent Achyranthes root over HZSM5-30 (HZSM-5 with SiO2/Al2O3 = 30) and HY30 (HY with SiO2/Al2O3 = 30) was performed using a two-stage fixed-bed reactor system. The catalytic fast pyrolysis of spent Achyranthes root over both HY30 and HZSM5-30 produced the much larger amount of aromatic hydrocarbons, compared to the non-catalytic fast pyrolysis, with a parallel decrease of oxygen-containing pyrolyzates. Owing to its robust pore structure and high acidity, it was the HZSM5-30 that produced the highest quality oil during the catalytic fast pyrolysis of spent Achyranthes root, having higher selectivity of mono-aromatic hydrocarbons compared to HY30.


Assuntos
Plantas Medicinais , Pirólise , Biomassa , Catálise , Temperatura Alta , Cinética , Dióxido de Silício
9.
AJNR Am J Neuroradiol ; 40(11): 1924-1931, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601577

RESUMO

BACKGROUND AND PURPOSE: Unruptured intracranial vertebrobasilar dissecting aneurysms with brain stem compression are difficult to treat. In the present study, the clinical and radiologic outcomes of unruptured intracranial vertebrobasilar dissecting aneurysms with brain stem compression based on different treatment modalities were evaluated. MATERIALS AND METHODS: This study included 28 patients with unruptured intracranial vertebrobasilar dissecting aneurysms with brain stem compression treated from January 2009 to December 2017. Treatment methods were observation (n = 6), stent-assisted coil embolization (n = 9), parent artery occlusion (n = 6), and flow diversion (n = 7). The data of baseline characteristics, change of aneurysm size, retreatment rate, stroke occurrence, and alteration of the mRS score were obtained from retrospective chart review. RESULTS: The initial size of dissecting aneurysms was largest in the flow diversion group (22.5 ± 7.7 mm), followed by parent artery occlusion (20.3 ± 8.4 mm), stent-assisted coil embolization (11.7 ± 2.2 mm), and observation (17.8 ± 5.5 mm; P = .01) groups. The reduction rate of aneurysm size was highest in the parent artery occlusion group (26.7 ± 32.1%), followed by flow diversion (14.1% ± 28.7%), stent-assisted coil embolization (-17.9 ± 30.3%), and observation (-31.5 ± 30.8%; P = .007) groups. Additional treatment was needed in the observation (4/6, 66.7%) and stent-assisted coil embolization (3/9, 33.3%; P = .017) groups. Improvement of the mRS score on follow-up was observed in the flow diversion (6/7, 85.7%) and parent artery occlusion (4/6, 66.7%) groups but not in the stent-assisted coil embolization and observation groups. A worsened mRS score was most common in the observation group (4/6, 66.7%), followed by stent-assisted coil embolization (3/9, 33.3%), parent artery occlusion (2/6, 33.3%), and flow diversion (0/7, 0%) groups. CONCLUSIONS: When treating intracranial vertebrobasilar dissecting aneurysms with brain stem compression, parent artery occlusion and flow diversion should be considered to reduce aneurysm size and improve the mRS score.


Assuntos
Dissecção Aórtica/terapia , Tronco Encefálico , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/terapia , Adolescente , Adulto , Idoso , Prótese Vascular , Criança , Feminino , Humanos , Aneurisma Intracraniano/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Stents , Resultado do Tratamento , Conduta Expectante , Adulto Jovem
10.
Malays J Pathol ; 40(2): 161-167, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30173234

RESUMO

Primary bone lymphoma (PBL) is an uncommon type of extranodal lymphoma involvement. An anaplastic large-cell lymphoma (ALCL) is an extremely rare type of PBL, and it remains unclear whether ALCLs that primarily involve the bone exhibit favourable or unfavourable biological behaviour, and whether they are similar to ALCLs in general, or not. We reported a case of ALK-positive ALCL with primary bone involvement, and reviewed the clinicopathological features of 22 previously reported cases. An ALCL with primary bone involvement mostly affects younger patients with a preponderant towards the involvement of axial-bone. The prognosis of an ALCL that primarily involves bone is unfavourable, compared with PBL generally. The ALK-positive ALCLs in PBLs had less decedents than the ALK-negative ALCLs with a statistical non-significance (p=0.198).


Assuntos
Neoplasias Ósseas/patologia , Linfoma Anaplásico de Células Grandes/patologia , Adulto , Quinase do Linfoma Anaplásico/biossíntese , Humanos , Masculino
11.
J Physiol Pharmacol ; 69(3)2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30149369

RESUMO

Repeated bouts of ulcerative colitis featured troublesome course of inflammatory bowel disease leading to fatal colitis-associated cancer, which is strongly associated with oxidative stress and sustained inflammation. Since oligonol, low molecular weighted polyphenol extracted from fruit lychee, showed antioxidative and anti-inflammatory actions, we hypothesized that oligonolcan prevent relapse of colitis. We compared oligonol with current gold standard therapeutics, sulfasalazine in preventive efficacy of relapse. First, dextran sulfate sodium (DSS)-induced colitis were made following pretreatment with oligonol, 10, 50, and 100 mg/kg for 7 days to measure therapeutic effect of oligonol and relapse model via repeated DSS administration was made following with either 50 mg/kg oligonol or 30 mg/kg sulfasalazine to explore relapse preventing action of oligonol in C57BL/6 mice. Detailed changes in colon were measured to explain molecular mechanisms. Pretreatment of 10, 50, 100 mg/kg oligonol (p.o.), significantly reduced DSS-induced colitis; total pathologic scores, colon length, and clinical symptom scores (P < 0.05). Oligonol pretreatment significantly decreased the levels of interleukin (IL)-1, IL-6, and tumor necrosis factor-α (TNF-α) as well as nuclear factor-κB (NF-κB), c-Fos, and c-Jun in affected colon tissues, but the expression of heme oxygenase-1 (HO-1) and NADH: quinone oxidoreductase-1(NQO-1) as well as total antioxidant concentration (P < 0.005) was significantly increased with oligonol. A relapse model established with repeated DSS administration led to high mortality. However, oligonol significantly ameliorated exacerbations of colitis, while sulfasalazine did not (P < 0.01). Significantly decreased expressions of cyclooxygenase-2 (COX-2), TNF-α, and macrophages inhibition were relapse preventing actions of oligonal, but significant action of oligonol relevant to relapse prevention was either significantly increased expressions of NQO-1 or significantly preserved mucin (P < 0.05). Concerted anti-inflammatory, antioxidative, and host defense enhancing actions of oligonol can be applied during maintenance therapy of IBD to prevent relapse of IBD.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Catequina/análogos & derivados , Colite Ulcerativa/tratamento farmacológico , Fenóis/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Catequina/farmacologia , Catequina/uso terapêutico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Citocinas/sangue , Sulfato de Dextrana , Heme Oxigenase-1/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Fenóis/farmacologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Prevenção Secundária
12.
Osteoarthritis Cartilage ; 25(10): 1738-1746, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28647468

RESUMO

OBJECTIVES: Symptomatic degenerative disc disease (DDD) is associated with neovascularization and nerve ingrowth into intervertebral discs (IVDs). Notochordal cells (NCs) are key cells that may lead to regeneration of IVDs. However, their activities under conditions of hypoxia, the real environment of IVD, are not well known. We hypothesized that NCs may inhibit neovascularization by interacting with endothelial cells (ECs) under hypoxia. DESIGN: Human IVDs were isolated and cultured to produce nucleus pulposus (NP) cell conditioned medium (NPCM). Immortalized human microvascular ECs were cultured in NPCM with notochordal cell-rich rabbit nucleus pulposus cells (rNC) under hypoxia. Vascular endothelial growth factor (VEGF), vascular cell adhesion molecule (VCAM), and interleukin-8 (IL-8) were analyzed by ELISA. Focal adhesion kinase (FAK), filamentous actin (F-actin), and platelet-derived growth factor (PDGF) were evaluated to investigate EC activity. Wound-healing migration assays were performed to examine EC migration. RESULTS: The VEGF level of EC cells cultured in NPCM was significantly higher under hypoxia compared to normoxia. VEGF expression was significantly decreased, and FAK, F-actin, PDGF expression were inhibited when ECs were cocultured with rNCs under hypoxia. ECs cocultured with rNC in NPCM showed significantly decreased migratory activity compared to those without rNC under hypoxia. CONCLUSIONS: The angiogenic capacity of ECs was significantly inhibited by NCs under hypoxia via a VEGF-related pathway. Our results suggest that NCs may play a key role in the development of IVDs by inhibiting vascular growth within the disc, and this may be a promising novel therapeutic strategy for targeting vascular ingrowth in symptomatic DDD.


Assuntos
Indutores da Angiogênese/metabolismo , Hipóxia Celular/fisiologia , Degeneração do Disco Intervertebral/patologia , Neovascularização Patológica/patologia , Notocorda/citologia , Animais , Comunicação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados , Células Endoteliais/metabolismo , Células Endoteliais/fisiologia , Humanos , Disco Intervertebral/irrigação sanguínea , Degeneração do Disco Intervertebral/metabolismo , Neovascularização Patológica/metabolismo , Núcleo Pulposo/citologia , Núcleo Pulposo/metabolismo , Coelhos , Fator A de Crescimento do Endotélio Vascular/fisiologia
13.
Bone Joint Res ; 6(3): 137-143, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28258117

RESUMO

OBJECTIVES: We evaluated the accuracy of augmented reality (AR)-based navigation assistance through simulation of bone tumours in a pig femur model. METHODS: We developed an AR-based navigation system for bone tumour resection, which could be used on a tablet PC. To simulate a bone tumour in the pig femur, a cortical window was made in the diaphysis and bone cement was inserted. A total of 133 pig femurs were used and tumour resection was simulated with AR-assisted resection (164 resection in 82 femurs, half by an orthropaedic oncology expert and half by an orthopaedic resident) and resection with the conventional method (82 resection in 41 femurs). In the conventional group, resection was performed after measuring the distance from the edge of the condyle to the expected resection margin with a ruler as per routine clinical practice. RESULTS: The mean error of 164 resections in 82 femurs in the AR group was 1.71 mm (0 to 6). The mean error of 82 resections in 41 femurs in the conventional resection group was 2.64 mm (0 to 11) (p < 0.05, one-way analysis of variance). The probabilities of a surgeon obtaining a 10 mm surgical margin with a 3 mm tolerance were 90.2% in AR-assisted resections, and 70.7% in conventional resections. CONCLUSION: We demonstrated that the accuracy of tumour resection was satisfactory with the help of the AR navigation system, with the tumour shown as a virtual template. In addition, this concept made the navigation system simple and available without additional cost or time.Cite this article: H. S. Cho, Y. K. Park, S. Gupta, C. Yoon, I. Han, H-S. Kim, H. Choi, J. Hong. Augmented reality in bone tumour resection: An experimental study. Bone Joint Res 2017;6:137-143.

15.
J Nanosci Nanotechnol ; 16(5): 4434-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483769

RESUMO

Catalytic pyrolysis of lignin, a major constituent of biomass, was performed. A nanoporous molecular sieve silicoaluminophosphate-11 (SAPO-11) was selected as catalyst. Thermogravimetric analysis showed that 500 degrees C was the optimal pyrolysis temperature. Pyrolyzer-gas chromatography/mass spectroscopy was used to investigate the pyrolysis product distribution. Production of phenolics, the dominant product from the pyrolysis of lignin, was promoted by the increase in the catalyst dose. In particular, low-molecular-mass phenolics were produced more over SAPO-11, while high-molecular-mass phenolics and double-bond-containing phenolics were produced less. The fraction of aromatic compounds, including benzene, toluene, xylene, and ethylbenzene, was also increased by catalytic reforming. The catalytic effects were more pronounced when the catalyst/biomass ratio was increased. The enhanced production of aromatic compounds by an acidic catalyst obtained in this study is in good agreement with the results of previous studies.


Assuntos
Compostos de Alumínio/química , Biocombustíveis , Calefação/métodos , Lignina/química , Nanopartículas Metálicas/ultraestrutura , Nanoporos/ultraestrutura , Fosfatos/química , Catálise , Teste de Materiais , Nanopartículas Metálicas/química , Porosidade , Dióxido de Silício/química
16.
J Nanosci Nanotechnol ; 16(5): 4483-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483778

RESUMO

Liquid phase plasma (LPP) method was applied, for the first time, to the impregnation of iron oxide nanoparticles onto graphene sheet. Iron oxide nanoparticles with the size of 50 nm were precipitated with uniform dispersion on the surface of graphene sheet. The amount of iron oxide nanoparticles precipitated on graphene sheets increased with increasing LPP process times. The XPS, Raman and EDX analyses showed that the iron oxide/graphene composites synthesized by the LPP process.

17.
J Nanosci Nanotechnol ; 16(5): 4493-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483780

RESUMO

Silver and silver oxide nanoparticles were impregnated on the surface of powdered activated carbon (PAC) using a single-step liquid phase plasma (LPP) method. Spherical silver and silver oxide nanoparticles of 20 to 100 nm size were dipersed evenly on the surface of PAC. The impregnated PAC exhibited a higher activity for the decomposition of bromate than bare PAC. The XPS, Raman and EDX analyses showed that the Ag/PAC composites synthesized by the LPP process.

18.
J Nanosci Nanotechnol ; 16(5): 4512-5, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483783

RESUMO

One step reaction composed of DCPD oligomerization and DCPD oligomer isomerization was investigated over nanoporous Al-MCM-41 catalysts. The effects of aluminum grafting over MCM-41 on the catalyst characteristics were studied with respect to the synthesis of TCPD isomer. Physical and chemical properties of the catalysts were analyzed by N2 adsorption, temperature-programmed desorption of ammonia, and infrared spectroscopy of adsorbed pyridine. The overall number of acid sites as well as the number of Lewis acid sites increased with increasing of aluminum content over MCM-41. When utilizing MCM-41 and Al-MCM-41 as the catalyst, DCPD oligomerization reaction activity greatly increased compared to the thermal reaction. The highest TCPD isomer selectivity over the Al-MCM-41 catalyst with the highest aluminum content could be ascribed to the largest amount of acid sites. This study showed an increased level of TCPD isomer selectivity by an increasing level of Lewis acid sites through aluminum addition over MCM-41.

19.
J Nanosci Nanotechnol ; 16(5): 4561-4, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483790

RESUMO

Wild reed was pyrolyzed over two nanoporous SBA-15 catalysts with different acid characteristics: Si-SBA-15 and Al-SBA-15. Al was grafted on Si-SBA-15 to increase the acidity and enhance the catalytic activity. Fast pyrolysis was carried out using a pyrolysis-gas chromatography/mass spectrometry system at 550 degrees C for real-time analysis of the products. Significant improvement of the product bio-oil quality was attained by catalytic reforming over nanoporous Al-SBA-15. The fraction of total oxygenates was reduced because of the decrease in. the fraction of ketones, aldehydes, and carboxylates, which deteriorate the fuel quality of bio-oil. On the other hand, the fractions of furans and aromatics, which are the chemicals with high value-added, were increased by the catalytic reforming. The catalytic activity of Al-SBA-15 was considerably higher than that of Si-SBA-15 because the incorporation of Al increased the catalyst acidity.

20.
J Nanosci Nanotechnol ; 16(5): 4638-42, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483803

RESUMO

The catalytic oxidation of toluene was carried out to investigate the effect of the support on the properties and performance of a supported palladium catalyst (1 wt% loading). γ-Al2O3), SiO2 and TiO2 were used as supports. The properties of the prepared catalysts were characterized by XRD, BET, PT, TPD, TPR, XPS and FE-TEM analyses. The experimental results showed that the order of catalytic performance was 1 wt% Pd/TiO2 > 1 wt% Pd/SiO2 > 1 wt% Pd/γ-Al2O3. A strong interaction between the palladium and support was found, which affected the palladium surface concentration and particle size. The higher catalytic activity of the Pd/TiO2 catalyst was attributed to the higher palladium surface concentration and larger particle size.

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