Immobilized Ag3PO4/GO on 3D nickel foam and its photocatalytic degradation of norfloxacin antibiotic under visible light.

In this study, a series of Ag3PO4/graphene oxide (GO) films were dip-coated on a metal nickel foam. The immobilized catalysts were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, ultraviolet-visible spectroscopy, Raman spectroscopy, high-resolution transmission electron microscopy and photoluminescence spectroscopy. The results show that Ag3PO4/GO was successfully supported on a nickel foam. The photocatalytic activity of the film catalyst under visible light was investigated by the degradation of norfloxacin, an antibiotic. Photocatalytic stability of this catalyst was also investigated. An optimized film exhibited superior activity and stability, the degradation rate of norfloxacin was about 83.68% in 100 min and the reaction rate constant k was 1.9 times that of pristine Ag3PO4. Further investigation found that photo-generated holes (h+) and superoxide anion radicals (·O2 -) are the main active species in the photodegradation process. The result indicates that the addition of GO inhibits the recombination of photogenerated electron-hole pairs, and thus has improved the photocatalytic activity and cyclic stability under visible light. The photocatalytic mechanism of the film catalyst was proposed. The prepared Ag3PO4/GO film catalyst is a promising candidate for treatment of wastewater containing antibiotics.

Effect of mixing method and storage time on dimensional stability of alginate impressions materials / 대한치과보철학회지

The purpose of this study is to compare the volume stability depending on the mixing methods and storage time for the conventional alginate and extended-pouralginate. Materials and methods: An arch-shaped metal model was fabricated, and one conventional alginate and two extended-pour alginates were used to take impressionsusing different mixing methods (hand and automatic). 120 impressions were taken (40 per each alginate) and stone models were made in accordance with the different storagetimes (immediate, 2 days, 5 days, and 6 days). The models were scanned with a 3D table scanner and dimensional change was measured by superimposing the scan data.Using SAS 9.4 (SAS Institute Inc., Cary, NC, USA), the general linear model and Tukey’s post hoc test was conducted for statistical analysis (P<.001). Results: There wasno statistically significant difference in the dimensional accuracy between two mixing methods, and the volume change was minimum when the stone was poured immediatelyin all groups. Dimensional accuracy showed a statistically significant difference between groups after 2 days of storage, and extended-pour alginate showed higher accuracyafter 5 days of storage comparing to conventional one. Large amounts of volume change were showed at 2 - 5 days for conventional alginate and at 5 - 6 days forextended pour alginate. Conclusion: The mixing method of alginate does not affect volume stability. Although extended-pour alginate has better volume stability than conventionalalginate for a long time, it is recommended to pour stone as soon as possible. (J Korean Acad Prosthodont 2020;58:86-94)

In situ surface formation of TiO2/Ti(NO2) hybrid nanocomposites with N2 APPJ treatment for efficient C2H4 photodegradation.

TiO2/Ti(NO2) hybrid films were prepared using N2 atmospheric pressure plasma jet treatment on TiO2 coating. The film structure and morphology have been investigated using optical emission spectra, Fourier-transform infrared spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The formed TiO2/Ti(NO2) photocatalystic thin films were applied for C2H4 photodegradation under UV irradiation. The results showed that the composite films exhibited superior photocatalytic activity over the untreated TiO2 film. The C2H4 concentration after 120 min varied from 12 to 6.2 mg/L, 6.7 mg/L, 7 mg/L for TiO2 with 1 min, 2 min and 3 min plasma treatment, respectively. In the banana storage experiment, the concentration of C2H4 was reduced from 15 to 9 ppm after 36 h with TiO2/Ti(NO2) nanocomposite film illuminated by UV light. The photocatalytic mechanism has been discussed. The composite film is able to more effectively separate the photo-excited electrons and holes, thus leading to the much high activity in C2H4 degradation. The current work has paved a way towards postharvest fruit preservation.

The Usefulness of FDG-PET/CT for the Prediction of Regional Lymph Node Metastases in Colorectal Cancer

PURPOSE: Proper preoperative staging is important in planning optimal therapy for individual patients and improving outcome. There is no ideal imaging methods for accurate colorectal cancer staging. The purpose of our study was to determine the usefulness of fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT) for the status of regional lymph node metastasis in colorectal cancer. METHODS: Two hundred forty six surgically resected colorectal cancers were retrospectively reviewed from Jan 2007 to Jul 2009. All patients underwent abdominal CT and FDG-PET/CT preoperatively. RESULTS: There were 129 males (52.4%) and the mean age was 62 (range: 25~88 years). Tumor location was the colon in 148 (59.7%) patients, and the rectum in 98 (40.3%) patients. Pathological stages were I: 43 (17.5%), II: 78 (31.7%), III: 81 (32.9%), IV: 44 (17.9%). Regional lymph node metastasis by pathological examination was 118 (48%) patients. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of regional lymph node staging were 66.4%, 66.7%, 64.8%, 68.3%, and 67%, respectively, with the FDG-PET/CT, and 57.1%, 71.3%, 64.8%, 64.3%, and 65%, respectively, with whole abdominal CT. The difference in the accuracy of nodal staging between the two modalities was not significant. CONCLUSION: The diagnostic accuracy of FDG-PET/CT for the assessment of regional lymph node metastasis in colorectal cancer was relatively low, and similar to that of abdominal CT. Therefore, further study will be needed to determine the clinical usefulness of preoperative FDG-PET/CT in colorectal cancer.

Surgery for a Complex Anal Fistula

PURPOSE: Because of the complexity and un-expectation of the courses and clinical features for the complex anal fistula, the management of it presents a difficult surgical challenge. Various techniques have been used, such as seton placement, advancement flap closure, muscle filling procedure, and fibrin glue injection. The classic lay-open and seton placement may distort the anal anatomy and result in poor functional outcomes, such as incontinence. Also, advancement flap techniques are associated with relatively high recurrence rates. This study assesses the results of surgery for a complex anal fistula, as performed in Hangun Hospital, Busan. Operative procedures were comprised of two or more separate procedures, including 1) a total fistulectomy, 2) muscle reconstruction, sometimes muscle transposition, 3) direct closure of the primary opening without making a mucosal advancement flap, and 4) a drainage procedure and/or other minor procedure. METHODS: Surgical procedures were performed on 22 patients (18 males) with a complex anal fistula between July 2004 and December 2004. The clinical and the manometric results were analyzed with respect to postoperative recurrence, delayed wound healing, and postoperative fecal incontinence. RESULTS: Nineteen of the 22 patients were completely healed without any sequelae. Treatment failure was encountered in one patient two months postoperatively, when an additional fistulotomy was performed to achieve a cure. There were two patients displaying delayed healing, who were successfully treated by curettage. No patient complained of postoperative fecal incontinence in either the clinical examination on the manometric study (mean resting pressure, 75.5+/-3.5 mmHg; maximal squeeze pressure, 175.7+/-10.3 mmHg). CONCLUSIONS: This short- term study suggests that a direct closure of the internal opening after a total fistulectomy can be an alternative surgical option for the treatment of a complex anal fistula.

Combined Multimodality Treatment including Surgery / 한국유방암학회지

An ipsilateral supraclavicular lymph node recurrence of breast cancer after surgery has been considered a predecessor to distant metastases. There still is a debate as to whether breast carcinoma patients with the isolated supraclavicular lymph node recurrence should be considered to have disseminated disease or if aggressive treatment, with curative intent, is justified. We report two cases of an isolated ipsilateral supraclavicular lymph node recurrence following modified radical mastectomy, and multimodality treatments with modified radical neck dissection, systemic chemotherapy and involved field radiotherapy. These patients have lived without locoregional recurrence or distant metastases for 3 and 2 years, respectively. Conclusively, we recommend aggressive combined multimodality treatments, including surgery, such as modified radical neck dissection or complete excision of the involved lymph nodes, systemic chemotherapy, and involved field radiotherapy, in patients with isolated supraclavicular lymph node recurrence, but with no other evidence of distant metastases.

Clinical, Pathologic and Immunohistochemical Features of Phyllodes Tumor of the Breast / 한국유방암학회지

The histological distinction between benign and malignant phyllodes tumors (PT) is often difficult and arbitrary. We analyzed clinical, histological features and expressions of Ki-67 and p53 using immunohistochemistry and estimate its significance in assessing the grade of malignancy and in predicting the clinical behavior of these tumors on 20 cases of PT of the breast (11 benign, 3 low-grade malignancy and 6 high-grade malignancy). Statistically significant differences between benign, low-grade malignant, and high-grade malignant PT by size of tumor, cellular atypism, stromal cellularity, margin of tumor, and number of mitotic figures. The mean labeling index (LI) of Ki-67 in high-grade malignant PT (9.6+/-9.6) was three-fold higher than that in benign PT (2.7+/-2.2), but this difference was not statistically significant (P=0.074). None of the benign PT were positive for p53, whereas 2 of 3 low-grade malignant and 3 of 6 high-grade malignant PT were positive for p53. Statistically significant differences in the pattern of p53 expression existed among the benign, low-grade malignant, and high-grade malignant lesions (P=0.018). Ki-67 LI and p53 expression were associated with numbers of mitotic figure, but were not associated with metastasis (P=0.546 and 0.216). Increased p53 immunoreactivity is present in high-grade and low-grade malignant PTs in contrast to benign PTs, and malignant PT had a higher Ki-67 LI than benign PT. Thus, p53 and Ki-67 expression may assist in distinguishing benign from malignant PT in diagnostically difficult cases.