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1.
Sci Rep ; 11(1): 530, 2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33436711

RESUMEN

Biodiesel is of high interest due to increased demand for energy with the concern regarding more sustainable production processes. However, an inevitable by-product is glycerol. Hence, the conversion of this by-product to higher-value chemicals, especially 1,3-propanediol (1,3-PDO) via glycerol hydrogenolysis reaction, is one of the most effective pathways towards a profitable process. In general, this process is catalyzed by a highly active Pt-based catalyst supported on γ-Al2O3. However, its low 1,3-PDO selectivity and stability due to surface deactivation of such catalysts remained. This led to the surface modification by WOx to improve both the selectivity by means of the increased Brønsted acidity and the stability in terms of Pt leaching-resistance. Hence, we applied experimental and density functional theory (DFT)-based techniques to study the fundamentals of how WOx modified the catalytic performance in the Pt/γ-Al2O3 catalyst and provided design guidelines. The effects of WOx promoter on improved activity were due to the shifting of the total density of states towards the antibonding region evident by the total density of states (TDOS) profile. On the improved 1,3-PDO selectivity, the main reason was the increasing number of Brønsted acid sites due to the added WOx promoter. Interestingly, the stability improvement was due to the strong metal-support interaction (SMSI) that occurred in the catalyst, like typical high leaching-resistant catalysts. Also, the observed strong metal-support-promoter interaction (SMSPI) is an additional effect preventing leaching. The SMSPI stemmed from additional bonding between the WOx species and the Pt active site, which significantly strengthened Pt adsorption to support and a high electron transfer from both Pt and Al2O3 to WOx promoter. This suggested that the promising promoter for our reaction performed in the liquid phase would improve the stability if SMSI occurred, where the special case of the WOx promoter would even highly improve the stability through SMSPI. Nevertheless, various promoters that can promote SMSPI need investigations.

2.
Gan To Kagaku Ryoho ; 44(12): 1613-1616, 2017 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-29394719

RESUMEN

A 66-year-old man diagnosed with rectal cancer underwent high anterior resection and received adjuvant chemotherapy (UFT plus UZEL). One year after the surgery, lung and para-aortic lymph node(PLN)metastases were identified. We chose mFOLFOX6 for first-line chemotherapy. After 7 courses, we changed the regimen to sLV5FU2 because of Grade 3 neuropathy. After 5 courses, to treat progressive disease(PD), we changed the regimen to FOLFIRI. Then, the patient had stable disease (SD), and surgical excision was performed for both lung and lymph node recurrence without adjuvant chemotherapy. Six years after the excision, a CT scan revealed PLNagain. We chose FOLFIRI plus cetuximab. After 9 courses, the lymph nodes decreased in size and there was no other recurrence; thus we performed resection. However, a third PLNrecurrence was identified 20 months after the resection. Chemotherapy has continued for 47 courses, and he has maintained SD for more than 2 years.


Asunto(s)
Neoplasias del Recto/terapia , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Aorta/patología , Terapia Combinada , Humanos , Metástasis Linfática , Masculino , Neoplasias del Recto/patología
3.
Surg Today ; 40(3): 228-33, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20180075

RESUMEN

PURPOSE: Patients diagnosed with early gastric cancer located in the middle third of the stomach have two major surgical options, namely a conventional distal gastrectomy with Billroth I anastomosis (DG) or a pylorus-preserving gastrectomy (PPG). Pyloruspreserving gastrectomy is thought to have greater functional benefits than DG, but the evaluation of its prognosis and outcome has so far been insufficient. METHODS: Between 1997 and 2007, 133 patients were diagnosed with early gastric cancer located in the middle third of the stomach. Distal gastrectomy was performed in 87 and PPG was performed in 46 of these patients. The clinicopathological characteristics were compared between the groups. RESULTS: There were fewer dissected lymph nodes in PPG (mean: 21.9) than in DG (mean: 30.4, P = 0.001). Complications were detected in 16.1% of DG patients and in 6.5% of PPG patients. The occurrence of stasis after PPG (6.5%) was similar to that observed after DG (6.9%). One patient in the DG group died from cancer recurrence, but cancer recurrence was not detected in the PPG group. Although the difference was not significant, the overall 5-year survival rate in the 46 PPG patients (95%) was better than that in the 87 DG patients (86%, P = 0.087). CONCLUSIONS: Pylorus-preserving gastrectomy patients had fewer postoperative complications than DG patients. The long-term follow-up of these patients will clarify the nutritional and prognostic benefits of PPG.


Asunto(s)
Gastrectomía/métodos , Píloro/cirugía , Neoplasias Gástricas/cirugía , Detección Precoz del Cáncer , Femenino , Humanos , Laparoscopía , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología , Análisis de Supervivencia , Resultado del Tratamiento
4.
J Phys Chem A ; 114(11): 3845-54, 2010 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-19719174

RESUMEN

The mechanism for the dehydrogenation of ethylbenzene over V, Cr, and Fe oxides loaded on activated carbon, powdered diamond, Al(2)O(3), and MgO was studied in the presence of CO(2). Vanadium oxide-loaded catalysts provided higher styrene yields under CO(2) than Ar flow. The transient response method was carried out to understand the reaction behaviors of lattice oxygen of various metal oxides on the support. The results showed that lattice oxygen of vanadium oxide (V=O) was consumed in the dehydrogenation reaction and that reduced vanadium oxide was reoxidized with CO(2). A similar redox cycle was observed on iron oxide-loaded activated carbon catalyst. Spectroscopic characterization revealed that vanadium oxide and iron oxide on the support were reduced to a low valence state during the dehydrogenation reaction, and that CO(2) could oxidize the reduced metal oxides. In contrast, chromium(III) oxide was not reduced during dehydrogenation. From these findings, the redox cycle over vanadium oxide- and iron oxide-loaded catalysts was concluded to be an important factor in promoting the catalytic activity with CO(2).

5.
Surg Today ; 39(11): 925-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19882312

RESUMEN

Locally advanced carcinomas arising in the hypopharynx, cervical esophagus, or thyroid are traditionally treated by resection of the hypopharynx and cervical esophagus. Various methods of reconstruction aiming to achieve safety and functionality have been reported, including the myocutaneous flap and the free jejunal graft. With advances in microscopic surgery, the free jejunal transplant is now used dominantly; however, this procedure is not without major risks. In this review we examine the short- and long-term complications of this procedure. We also describe our technique of free jejunal graft reconstruction after pharyngoesophagectomy and total laryngectomy with definitive tracheostomy. We used free jejunal graft reconstruction after resection with hypopharyngeal cancer or thyroid cancers in 22 patients. Twenty-one of these patients acquired a good quality of life, but one died after loss of the jejunal graft. Thus, using a free jejunal graft for reconstruction of the hypopharynx or cervical esophagus can be very useful in improving the quality of life of patients.


Asunto(s)
Trastornos de Deglución/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Yeyuno/trasplante , Procedimientos de Cirugía Plástica/métodos , Deglución/fisiología , Trastornos de Deglución/etiología , Trastornos de Deglución/fisiopatología , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/fisiopatología , Humanos
6.
Gastric Cancer ; 12(2): 95-100, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19562463

RESUMEN

BACKGROUND: Interleukin-6 (IL-6) is known to be a multifunctional cytokine and IL-10 is an immunosuppressive factor. Both have been reported to be related to the disease prognosis in some human solid tumors. In the present study, we evaluated the clinical significance of preoperative serum IL-6 and IL-10 levels as new tumor markers in patients with gastric cancer (GC). METHODS: Preoperative serum samples from 90 patients with GC and 9 normal healthy volunteers were assayed. Levels of IL-6 and IL-10 were determined by enzyme-linked immunosorbent assay (ELISA). The clinical significance of serum IL-6 and IL-10 levels was evaluated and compared with serum carcinoembryonic antigen (CEA) levels and serum C-reactive protein (CRP) levels in these patients. RESULTS: The serum level of IL-6 was significantly higher in the GC patients than in the healthy subjects. Serum IL-6 levels were strongly correlated with CRP levels, but did not correlate with CEA or carbohydrate antigen (CA) 19-9 levels. Serum IL-10 levels did not correlate with CEA, CA19-9, or CRP. Strong positive correlations between serum IL-6 levels and tumor size and tumor stage were observed. On the other hand, IL-10 did not correlate with such clinicopathological findings of tumors. However, high serum IL-10 levels were associated with a worse prognosis in the GC patients, independently of their tumor stage. CONCLUSION: These findings indicate that serum IL-6 may suggest gastric cancer progression. On the other hand, IL-10 may play an important role in host immunity and the prognosis of GC patients.


Asunto(s)
Biomarcadores de Tumor/sangre , Interleucina-10/sangre , Interleucina-6/sangre , Neoplasias Gástricas/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/inmunología , Proteína C-Reactiva/análisis , Antígeno Carcinoembrionario/sangre , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Interleucina-10/inmunología , Interleucina-6/inmunología , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias Gástricas/inmunología
7.
Surg Today ; 39(4): 290-4, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19319634

RESUMEN

The prognosis of patients with scirrhous gastric cancer (SGC) is extremely poor. However, recent advances in therapeutic strategies against SGC, using effective anticancer drugs, have prolonged the survival of patients with SGC. This paper reviews the recent therapeutic outcomes of this type of gastric cancer and introduces a new treatment protocol for SGC.


Asunto(s)
Adenocarcinoma Escirroso/tratamiento farmacológico , Adenocarcinoma Escirroso/cirugía , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/cirugía , Adenocarcinoma Escirroso/diagnóstico , Antineoplásicos/uso terapéutico , Quimioterapia Adyuvante , Protocolos Clínicos , Terapia Combinada , Gastrectomía/métodos , Humanos , Laparoscopía , Evaluación de Procesos y Resultados en Atención de Salud , Pronóstico , Radioterapia Adyuvante , Neoplasias Gástricas/diagnóstico , Análisis de Supervivencia
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