RESUMEN
The development of a highly active photocatalyst for visible-light water splitting requires a high-quality semiconductor material and a cocatalyst, which promote both the migration of photogenerated charge carriers and surface redox reactions. In this work, a cocatalyst was loaded onto an oxyfluoride photocatalyst, Pb2Ti2O5.4F1.2, to improve the water oxidation activity. Among the metal oxides examined as cocatalysts, RuO2 was found to be the most suitable, and the O2 evolution activity depended on the preparation conditions for Ru/Pb2Ti2O5.4F1.2. The highest activity was obtained with RuCl3-impregnated Pb2Ti2O5.4F1.2 heated under a flow of H2 at 523â K. The H2-treated Ru/Pb2Ti2O5.4F1.2 showed an O2 evolution rate an order of magnitude higher than those for the analogues without the H2 treatment (e. g., RuO2/Pb2Ti2O5.4F1.2). Physicochemical analyses by X-ray absorption fine-structure spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and time-resolved microwave conductivity measurements indicated that the optimized photocatalyst contained partially reduced RuO2 species with a particle size of ~5â nm. These partially reduced species effectively trapped the photogenerated charge carriers and promoted the oxidation of water into O2. The optimized Ru/Pb2Ti2O5.4F1.2 could function as an O2-evolving photocatalyst in Z-scheme overall water splitting, in combination with an Ru-loaded, Rh-doped SrTiO3 photocatalyst.
RESUMEN
BACKGROUND/AIM: NAD(P)H dehydrogenase [quinone] 1 (NQO1), an antioxidant enzyme, confers resistance to anticancer agents. NQO1 C609T is a single-nucleotide polymorphism associated with reduced protein expression in the non-neoplastic esophageal squamous epithelium (ESE). This study aimed to investigate immunohistochemical NQO1 expression in non-neoplastic ESE and to elucidate its prognostic significance in patients with esophageal squamous cell carcinoma (ESCC) undergoing neoadjuvant therapy followed by esophagectomy. MATERIALS AND METHODS: NQO1 expression in non-neoplastic ESE was determined in surgical specimens from 83 patients with ESCC using immunohistochemistry. The association between NQO1 expression and clinicopathological factors, and the prognostic significance of NQO1 expression for relapse-free survival (RFS) were statistically evaluated. RESULTS: Patients with complete loss or weak NQO1 expression and patients with moderate or strong NQO1 expression were classified into the NQO1-negative (n=29) and NQO1-positive (n=54) groups, respectively. The downstaging of T classification status after neoadjuvant therapy was significantly more frequent in the NQO1-negative group than in the NQO1-positive group (59% vs. 33%; p=0.036). The NQO1-negative group had significantly more favorable RFS than the NQO1-positive group (p=0.035). Multivariate survival analysis demonstrated that NQO1 negative expression had a favorable prognostic impact on RFS (HR=0.332; 95%CI=0.136-0.812; p=0.016). CONCLUSION: Immunohistochemical evaluation of NQO1 expression in non-neoplastic ESE has clinical utility for predicting patient prognosis after neoadjuvant therapy followed by esophagectomy and might be helpful for selecting candidates for adjuvant therapy to treat ESCC.
Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , NAD(P)H Deshidrogenasa (Quinona) , Humanos , NAD(P)H Deshidrogenasa (Quinona)/genética , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidad , Femenino , Masculino , Persona de Mediana Edad , Pronóstico , Anciano , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/genética , Esofagectomía , Terapia Neoadyuvante , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/metabolismo , Adulto , Inmunohistoquímica , Supervivencia sin Enfermedad , Anciano de 80 o más AñosRESUMEN
The patient was a 71-year-old man with a diagnosis of duodenal carcinoma. Abdominal computed tomography(CT) showed no distant metastasis, and he underwent subtotal stomach-preserving pancreaticoduodenectomy. Postoperative adjuvant chemotherapy was not administered. A left supraclavicular lymph node recurrence was detected on CT 15 months after surgery. Capecitabine and oxaliplatin(CAPOX)therapy was administered and the metastatic lesion shrank. Positron emission tomography(PET)-CT showed no lesions at other sites and left cervical lymph node dissection was performed 5 months after the recurrence. Postoperative adjuvant therapy with S-1 was administered for 6 months. However, 2 years and 10 months after the first recurrence, CT showed recurrence in the left supraclavicular lymph node. CAPOX therapy was resumed, but due to an allergic reaction to oxaliplatin, the patient was treated with capecitabine alone. The recurrent lesion was gradually increased in size, and FOLFIRI therapy was introduced. One year and 5 months after secondary recurrence, PET-CT showed that the second recurrent lesion had grown but was confined to the left supraclavicular lymph node, so radiation therapy(60 Gy)to the left neck was performed. The disease was stable for about 10 months and chemotherapy could be discontinued. The lesion increased in size thereafter, and the patient died 7 years after initial surgery.
