Enhanced photocatalytic efficiency of porous ZnO coral-like nanoplates for organic dye degradation.

ZnO nanomaterials have been extensively used as photocatalysts for the removal of pollutants in aqueous environments. This study explores the enhanced photocatalytic performance of porous ZnO coral-like nanoplates synthesized via a one-pot wet-chemical method and subsequent annealing treatment. Characterization through scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), powder X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, photoluminescence (PL) spectroscopy, and Brunauer-Emmett-Teller (BET) measurements confirmed the nanoplates' porous structure, single-crystal structure, 100 nm thickness, and 80 nm pore size. These unique structural characteristics of the ZnO coral-like nanoplates enabled effective photodegradation of the organic dye rhodamine B (RhB) under visible light irradiation. Under simulated sunlight, the ZnO photocatalyst exhibited exceptional performance, achieving a 97.3% removal rate of RhB after 210 minutes of irradiation. The prepared ZnO photocatalyst also showed remarkable photostability and regeneration capability for RhB photodegradation with a decreased efficiency of less than 15% after eight testing cycles. The potential mechanism of the ZnO photocatalyst toward RhB degradation was also studied and is discussed in detail.

Histopathological Characteristics of Gastrointestinal Stromal Tumors in a Cohort of Vietnamese Patients.

INTRODUCTION: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal system. Histopathological examination takes an important part in confirming the subtypes of GISTs, to choose appropriate therapeutics for patients. This study aims to explore the histopathological characteristics and evaluate the relationship between malignant risk classification (according to Armed Forces Institute of Pathology criteria) and the histopathological features of GISTs in a cohort of Vietnamese patients. METHODS: We reviewed 89 patients with primary GIST who underwent surgery between 2014 and 2019 at Hue Central Hospital, Vietnam. We investigated histopathological characteristics and immunohistochemical findings of all patients. RESULTS: The average age was 55.9 ± 11.9 years. A tumor size of 2-5 cm accounted for 64.1%. The most common position was at the stomach which accounted for 48.5%. Among the subtypes of GIST, spindle cells were seen in 85.9% of patients; epithelial form 10.9%; multi-morphology (3.2%). 97.4% of the samples were positive for CD117, 61.5% of cases were positive for CD34; and no case was positive for Desmin. The rate of high-risk GIST was dominant (46.9%) as compared to the intermediate-risk (28.1%), low-risk (0.3%-2%), and very low-risk groups (4.7%). CONCLUSIONS: This study demonstrates the histopathological characteristics of GIST and emphasizes the significant rate of high-risk GIST.