ABSTRACT
Background: We retrospectively evaluated the usefulness of an elevated glucose-to-lymphocyte ratio (GLR) as a sensitive prognostic biomarker of disease-specific survival in 338 patients who underwent surgical resection of pancreatic ductal adenocarcinoma (PDAC). Methods: The optimal GLR cutoff value was determined using the method of Contal and O'Quigley. Patient demographics, clinical information, and imaging data were analyzed to identify preoperative predictors of long-term survival outcomes. Results: Elevated GLR correlated significantly with aggressive tumor biologic behaviors, such as a high carbohydrate antigen (CA) 19-9 level (p = 0.003) and large tumor size (p = 0.011). Multivariate analysis identified (1) GLR > 92.72 [hazard ratio (HR) = 2.475, p < 0.001], (2) CA 19-9 level > 145.35 (HR = 1.577, p = 0.068), and (3) symptoms (p = 0.064) as independent predictors of long-term, cancer-specific survival. These three risk factors were used to group patients into groups 1 (0 factors), 2 (1-2 factors), and 3 (3 factors), which corresponded to significantly different 5-year overall survival rates (50.2%, 34.6%, and 11.7%, respectively; p < 0.001). Conclusions: An elevated preoperative GLR is associated with aggressive tumor characteristics and is an independent predictor of poor postoperative prognosis in patients with PDAC. Further prospective studies are required to verify these findings.
ABSTRACT
During pancreaticoduodenectomy after transhiatal esophagectomy, the preservation of the blood supply to the gastric conduit is technically difficult due to adhesion. Here, we present a case of successful pancreaticoduodenectomy after neoadjuvant chemotherapy in a patient with pancreatic head cancer who previously underwent subtotal esophagectomy with gastric reconstruction for esophageal cancer. A 69-year-old man who had undergone cholecystectomy 20 years prior and transhiatal esophagectomy 6 years prior for esophageal cancer presented to our hospital for indigestion. Computed tomography and magnetic resonance imaging revealed a 2.8-cm pancreatic head cancer, with focal abutment with the gastroduodenal artery, right gastroepiploic artery, and right colic vein. After discussion with the multidisciplinary team, the patient underwent neoadjuvant chemotherapy with six cycles of FOFIRINOX. The patient successfully underwent pancreatectomy, which preserved the pylorus. We preserved the gap between the gastric tube and the left lateral segment of the liver to avoid injuring the right gastric artery and vein. The tumor was found to be invading the gastroduodenal artery; thus, we performed R0 resection of the gastroduodenal artery and an end-to-end anastomosis between the gastroduodenal artery and the right gastroepiploic artery. After completing the surgical procedure, we added Braun anastomosis to reduce the incidence of delayed gastric emptying. Pancreaticoduodenectomy after transhiatal esophagectomy can be performed with preservation of the blood supply to the neogastric tube by reconstructing the major vessels, even in cases in which the tumor is invading or abutting the major vessels.
ABSTRACT
This study used multicenter data to compare the oncological safety of transduodenal ampullectomy (TDA) with that of pylorus-preserving pancreatoduodenectomy (PPPD) in early ampulla of Vater (AoV) cancer. Data for patients who underwent surgical resection for AoV cancer (pTis-T2 stage) from January 2000 to September 2019 were collected from 15 institutions. The clinicopathologic characteristics and survival outcomes were compared between the PPPD and TDA groups. A total of 486 patients were enrolled (PPPD, 418; TDA, 68). The oncologic behavior in the PPPD group was more aggressive than that in the TDA group at all T stages: larger tumor size (p = 0.034), advanced T stage (p < 0.001), aggressive cell differentiation (p < 0.001), and more lymphovascular invasion (p = 0.002). Five-year disease-free survival (DFS) and overall survival (OS) did not differ between the two groups when considering all T stages or only the Tis+T1 group. Among T1 patients, PPPD produced significantly better DFS (PPPD vs. TDA, 84.8% vs. 66.6%, p = 0.040) and superior OS (PPPD vs. TDA, 89.1% vs. 68.0%, p = 0.056) than TDA. Lymph node dissection (LND) in the TDA group did not affect DFS or OS (TDA + LND vs. TDA-only, DFS, p = 0.784; OS, p = 0.870). In conclusion, PPPD should be the standard procedure for early AoV cancer.
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PURPOSE: The aim of this study was to perform a histological analysis of the effect of a ytterbium-doped fiber (YDF) laser on oral buccal mucosa tissue in vivo to simulate its effect on the mucosa of the lower urinary tract. METHODS: A total of 90 8-week-old Sprague-Dawley rats were anesthetized with urethrane (1.2 g/kg intraperitoneally). A prespecified inner buccal mucosal site was irradiated with a YDF master-oscillator power amplifier (MOPA) system for 60 seconds, with output power settings of 0.5, 1, and 2 W, respectively, in 3 treatment groups. Specimens of irradiated tissue were harvested at 2 hours, 24 hours, 2 weeks, and 4 weeks after irradiation. The tissue specimens were stained with hematoxylin and eosin for histological analysis. RESULTS: In the group treated with 0.5 W, basal cell elongation and vacuolization were observed at 2 hours and 24 hours after treatment, respectively. No evident injury was observed after 2 or 4 weeks. The group treated with 1 W presented partial basal layer separation, and even complete epidermal ablation, within 2 hours. At 24 hours after laser treatment, new capillaries on an edematous background of fibroblasts and myofibroblasts, as well as profuse infiltration of the neutrophils to the basal layer, were observed. Collagen deposition and reepithelization were observed in specimens taken 2 weeks and 4 weeks after treatment. The group treated with 2 W presented bigger and deeper injuries at 2 hours after irradiation. Meanwhile, subepidermal bullae with full-thickness epidermal necrosis and underlying inflammatory infiltrate were observed 24 hours after treatment. The presence of fibrous connective tissue and collagen deposition were observed 2 weeks and 4 weeks after the treatment. CONCLUSIONS: To our knowledge, this is the first report regarding the effect of a YDF laser on living tissue. Our study demonstrated that the typical histological findings of the tissue reaction to the YDF MOPA apparatus were very similar to those associated with thermal injuries. The extent and degree of tissue damage increased proportionally to the output power.
ABSTRACT
We propose a fiber-optic-plasmonic hybrid device that is based on a corrugation-assisted metal-coated angled fiber facet (CA-MCAFF) for wavelength-dependent off-axis directional beaming (WODB). The device breaks into two key structures: One is the MCAFF structure, which is a modified Kretschmann configuration implemented onto a fiber platform, thereby being able to generate a unidirectional surface plasmon with dramatically enhanced properties in terms of non-confined diffracted radiation loss and operational bandwidth. The other is the periodic corrugation structure put on the MCAFF, thereby enabling WODB functionality out of the whole structures. The corrugated metal surface out-couples the surface plasmon mode to free-space optical radiation into a direction that varies with the wavelength of the optical radiation with excellent linearity. We perform extensive numerical investigations based on the finite-element-method and analyze the out-coupling efficiency (OCEout) and spectral bandwidth (SBout) of the proposed device for various designs and conditions. We determine the seven structural parameters of the device via taking sequential optimization steps. We deduce two optimal conditions particularly for the fiber-facet angle, in terms of the averaged OCEout or the SBout in the whole visible wavelength range (400 - 700 nm), which eventually leads to OCEout = 30.4% and SBout = 230 nm or to OCEout = 24.5% and SBout = 245 nm, respectively. These results suggest substantial enhancements in both OCEout and SBout, in comparison with the performance properties of a typical nano-slit-based device having a similar type of WODB functionality. The proposed CA-MCAFF is a simple, compact and efficient WODB device that is fully compatible with the state-of-the-art optical fiber technology.
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Graphene oxide films were prepared by a facile ball milling process. The milling time and the amount of the acryl type polymer dispersion agent were controlled to obtain well dispersed graphene oxide solution in ethanol. Consequently, the transparent and conducting graphene oxide film which had 69% transmittance and 1.5 x 10(6) ohm/sq surface resistance was produced by bar coating the solution on a PET substrate. The electrical property of the graphene oxide film could be further improved to 2.1 x 10(5) ohm/sq by hydrazine vapor reduction.
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The rapid expansion of supercritical carbon dioxide solutions into a liquid solvent (RESOLV) technique with environmentally benign supercritical carbon dioxide was used to produce semi-conducting polymeric nanoparticles of fluoroalkyl ester substituted thiophenes. When the supercritical solutions of the conjugated polymer, poly[2-(3-thienyl) acetyl-3,3,4,4,5,5,6,6,7,7,8,8,8,tridecafluoro-1-octanate] (PSFTE) were expanded into aqueous solutions through a small capillary nozzle (150 microm), spherical nanoparticles in the range of 50-100 nm were obtained. However, after 15 min of expansion, the particles tended to aggregate to form larger objects due to the high surface energy of the polymeric nanoparticles. In order to prevent the agglomeration of particles, a relatively low concentration of sodium dodecyl sulphate (SDS) or NaCI was used as a stabilizing agent in aqueous solution. While NaCI did not give enough stabilization to the system, uniform spherical nanoparticles of PSFTE having an average size of 45 nm were successfully obtained by SDS stabilization.
