Small area estimation of receiver operating characteristic curves for ordinal data under stochastic ordering.

There has been a recent increase in the diagnosis of diseases through radiographic images such as x-rays, magnetic resonance imaging, and computed tomography. The outcome of a radiological diagnostic test is often in the form of discrete ordinal data, and we usually summarize the performance of the diagnostic test using the receiver operating characteristic (ROC) curve and the area under the curve (AUC). The ROC curve will be concave and called proper when the outcomes of the diagnostic test in the actually positive subjects are higher than in the actually negative subjects. The diagnostic test for disease detection is clinically useful when a ROC curve is proper. In this study, we develop a hierarchical Bayesian model to estimate the proper ROC curve and AUC using stochastic ordering in several domains when the outcome of the diagnostic test is discrete ordinal data and compare it with the model without stochastic ordering. The model without stochastic ordering can estimate the improper ROC curve with a nonconcave shape or a hook when the true ROC curve of the population is a proper ROC curve. Therefore, the model with stochastic ordering is preferable over the model without stochastic ordering to estimate the proper ROC curve with clinical usefulness for ordinal data.

Perioperative red blood cell transfusion and mortality following heart transplantation: A retrospective nationwide population-based study between 2007 and 2016 in Korea.

BACKGROUND: Patients undergoing heart transplantation (HT) frequently receive perioperative red blood cell (RBC) transfusions, but the impact of perioperative transfusion on clinical outcomes after HT remains unclear. METHODS: All adult HTs performed in Korea between 2007 and 2016 were analyzed using data from the National Health Insurance Service. Patients were classified into four groups based on the number of RBC units transfused during hospital admission for HT: 0, 1 to 2, 3 to 5, and greater than or equal to 6 units. In-hospital and long-term mortality rates were compared among the groups. RESULTS: In total, 833 adults HTs were included in the study. The overall in-hospital mortality rate was 8.4% (70 of 833), with no mortality occurring in patients who received no transfusion. The in-hospital mortality rate was higher in patients requiring greater than or equal to 6 units (25.1%) than in patients who received 1 to 2 units (0.3%) and 3 to 5 units (2.7%; P < .001). Patients who received greater than or equal to 6 units of RBCs had a significantly higher risk of all-cause mortality after HT compared to patients who received no transfusion (hazard ratio [95% confidence interval], 5.99 [1.46-24.56]; P = .012). Long-term survival rate was also lower in patients who received transfusions of greater than or equal to 6 units of RBCs than in patients who received no transfusion (P < .001). CONCLUSIONS: Perioperative transfusion of greater than or equal to 6 units of RBCs may be associated with an increased risk of in-hospital and long-term mortality after HT.

Institutional Case-Volume and Mortality After Heart Transplantation.

The relationship between lower institutional case-volume and higher mortality after complex high-risk procedures has been shown. The aim of this study is to examine the effect of institutional volume on patient outcome after heart transplantation (HT) in the entire Korean population.We analyzed all adult HTs performed in Korea between 2007 and 2016 using data from the National Health Insurance Service. The association between case-volume and in-hospital mortality after HT was analyzed after categorizing hospitals performing HT into low-, medium-, or high-volume centers depending on the number of HTs performed. The effect of case-volume on long-term mortality was also assessed.A total of 833 adult HTs were performed in 17 centers. In-hospital mortality was 3.7% (13/356), 10.1% (38/375), and 18.6% (19/102) in high-, medium-, and low-volume centers, respectively. Medium-, and low-volume centers showed increased risk of in-hospital mortality (odds ratio [95% confidence interval]; 2.11 [1.42-3.13] and 3.68 [2.16-2.27], respectively.). Long-term survival of up to 10 years was worse in lower-volume centers compared to high-volume centers (P < 0.001).In conclusion, lower case-volume was associated with increased in-hospital mortality and long-term mortality after HT. A minimum case-volume mandate may be required for hospitals performing HT to ensure the best patient outcome and effective resource allocation.

Adult lung transplantation case-volume and in-hospital and long-term mortality in Korea.

BACKGROUND: The inverse relationship between case-volume and surgical mortality has been reported in complex surgical procedures. The aim of this study was to evaluate the effect of case-volume on mortality after lung transplantation in Korea. METHODS: The National Health Insurance Service data was used to analyse all adult lung transplantations in Korea between 2007 and 2016. Institutions were categorized into low-volume (< 5 lung transplantations/year) centers or high-volume (≥ 5 lung transplantations/year) centers. Risk-adjusted in-hospital mortality and long-term survival according to case-volume was evaluated. RESULTS: A total of 315 adult recipients underwent lung transplantation at 7 centers. The odds ratio for in-hospital mortality in low-volume centers was similar to high-volume centers (OR, 1.496; 95% CI, 0.81-2.76; p = 0.197). Log-rank analysis of Kaplan-Meier curves according to case-volume also did not show a difference in long-term survival between high- and low-volume centers (p = 0.052). CONCLUSIONS: There was no association between case-volume and in-hospital mortality after lung transplantation in Korea, although there was a tendency towards better long-term survival associated with high-volume centers.

Aortoenteric fistula following overlap esophagojejunal anastomosis using linear staplers for cancer of the esophagogastric junction: a case report.

BACKGROUND: Aortoenteric fistula (AEF), occasionally reported as a fatal complication after aortic or other vascular procedures, is a communication between the aorta and the digestive tract. AEF as a fatal complication of overlap esophagojejunostomy after esophagogastrectomy has not been reported previously. Herein, we report a case of AEF after laparoscopic proximal gastrectomy and transhiatal lower esophagectomy for cancer of the esophagogastric junction, in which linear staplers were used for overlap esophagojejunostomy. CASE PRESENTATION: A 66-year-old woman with advanced cancer of the esophagogastric junction underwent laparoscopic proximal gastrectomy and transhiatal lower esophagectomy with abdominal and lower mediastinal lymphadenectomy. Double tract reconstruction by the overlap method was performed. The patient was discharged from the hospital 10 days after surgery with a good postoperative course. However, she developed sudden-onset massive hematemesis and melena the day after discharge, resulting in death. Autopsy revealed that the stapled edge of the entry hole of the overlap esophagojejunostomy was in direct contact with the descending aorta. AEF was found at the esophagojejunostomy site. CONCLUSIONS: To our knowledge, this is the first report of AEF as a fatal complication of overlap esophagojejunostomy after esophagogastrectomy. Although we could not definitively identify the cause of the AEF, it could be attributed to direct contact between the stapled edge and the bare thoracic aorta over a period of 10 days. To avoid direct contact with the aorta in esophagojejunostomy with linear staplers, all stapled edges should be covered by suturing and attention should be paid to the position of these edges.

Effect of Institutional Case Volume on In-hospital Mortality After Living Donor Liver Transplantation: Analysis of 7073 Cases Between 2007 and 2016 in Korea.

BACKGROUND: The relationship between institutional case volume and clinical outcomes after living donor liver transplantation is not clarified. METHODS: We conducted a nationwide retrospective cohort study using the database of Korean National Healthcare Insurance Service. Between January 2007 and December 2016, 7073 adult living donor liver transplantations were performed at 50 centers in Korea. Centers were categorized according to the average annual number of liver transplantations: >50, 10 to 50, and <10. RESULTS: In-hospital mortality rates in the high-, medium-, and low-volume centers were 2.8%, 4.1%, and 6.7%, respectively. After adjustment, in-hospital mortality was significantly higher in low-volume centers (adjusted odds ratio, 2.287; 95% confidence interval, 1.471-3.557; P < 0.001) and medium-volume centers (adjusted odds ratio, 1.676; 95% confidence interval, 1.089-2.578; P = 0.019) compared with high-volume centers. Long-term survival for up to 9 years was better, and intensive care unit and hospital length of stay were shorter in high-volume centers. CONCLUSIONS: Centers with higher case volume (>50 liver transplantations/year) had better outcomes after living donor liver transplantation, including in-hospital mortality and long-term mortality compared with centers with lower case volume (≤50 liver transplantations/year).

Effect of Case Volume on Mortality After Pediatric Liver Transplantation in Korea.

BACKGROUND: The purpose of this study was to evaluate whether institutional case-volume affects clinical outcomes after pediatric liver transplantation. METHODS: We conducted a nationwide retrospective cohort study using the database of Korean National Healthcare Insurance Service. Between January 2007 and December 2016, 521 pediatric liver transplantations were performed at 22 centers in Korea. Centers were categorized according to the average annual number of liver transplantations: >10, 1 to 10, and <1. RESULTS: In-hospital mortality rates in the high-, medium-, and low-volume centers were 5.8%, 12.5%, and 32.1%, respectively. After adjustment, in-hospital mortality was significantly higher in low-volume centers (adjusted odds ratio, 9.693; 95% confidence interval, 4.636-20.268; P < 0.001) and medium-volume centers (adjusted odds ratio, 3.393; 95% confidence interval, 1.980-5.813; P < 0.001) compared to high-volume centers. Long-term survival for up to 9 years was better in high-volume centers. CONCLUSIONS: Centers with higher case volume (>10 pediatric liver transplantations/y) had better outcomes after pediatric liver transplantation, including in-hospital mortality and long-term mortality, compared to centers with lower case volume (≤10 liver transplantations/y).

CCQM-K121 - Monoterpenes in Nitrogen at 2.5 nmol mol-1 Final Report.

The growing awareness of climate change, and continuing concerns regarding tropospheric and stratospheric chemistry, will require future measurements and standards for compounds linked to these issues. To globally monitor and control the emissions of these species in the atmosphere, it is necessary to demonstrate measurement equivalence at the highest levels of accuracy for assigned values of standards. This report describes the results of a key comparison for several important monoterpene species, which are relevant to atmospheric chemistry and climate. The comparison samples include α-pinene, 3-carene, R-limonene and 1,8-cineole in a nitrogen matrix gas, at a 2.5 nmol mol-1 amount-of-substance fraction. The objective of this key comparison is to evaluate the participants' capabilities to measure trace-level monoterpenes using their own calibration techniques.

Squamous cell carcinoma of the extrahepatic bile duct with metachronous para-aortic lymph node metastasis successfully treated with S-1 plus cisplatin.

The most common histological classification of bile duct cancer is adenocarcinoma and squamous cell carcinoma (SCC) is relatively rare. We report a case of a 78-year-old man with SCC of the extrahepatic bile duct associated with metachronous para-aortic lymph node metastasis. He had undergone subtotal stomach-preserving pancreatoduodenectomy. The pathological findings demonstrated moderately differentiated SCC of the distal extrahepatic bile duct (T1N1M0, stage IIB). 6 months after surgery, recurrence of the para-aortic lymph node was shown in abdominal CT. 5 courses of tegafur/gimeracil/oteracil (S-1) plus cisplatin therapy was performed and the para-aortic lymph node disappeared, confirmed as complete response by imaging findings. The patient is alive without recurrence, 10 months after recurrence and chemotherapy.

Strangulated transmesosigmoid hernia as a late complication of a fall from a height: A case report.

INTRODUCTION: A transmesosigmoid hernia is defined as small bowel herniation through a complete defect involving both layers of the sigmoid mesentery. Blunt trauma injury to the sigmoid mesocolon has been reported only rarely. We herein report a case of a strangulated transmesosigmoid hernia associated with a history of a fall from a height. PRESENTATION OF CASE: A 43-year-old woman presented to our hospital for evaluation of vomiting. She had no history of abdominal surgery but had sustained a complete spinal cord injury and pelvic fracture secondary to a fall from a height 25 years earlier. A computed tomography scan of her abdomen and pelvis demonstrated a closed loop of small bowel in the pelvis, with a zone of transition in the left lower abdomen. Although the cause of the obstruction was difficult to establish, ischemia was strongly suspected; therefore, the decision was made to perform emergency exploratory laparoscopy. During laparoscopy, a loop of ileum was observed to have herniated through a full-thickness defect in the sigmoid mesocolon, consistent with a transmesosigmoid hernia. The herniated loop was strangulated but not gangrenous and was successfully reduced using laparoscopic graspers. The incarcerated small bowel appeared viable and was therefore not resected. The defect was closed with a running suture. The patient had an uneventful postoperative course with no recurrence. DISCUSSION AND CONCLUSION: Abdominal blunt trauma can cause sigmoid mesenteric rupture resulting in a transmesosigmoid hernia. In the management of transmesosigmoid hernias, laparoscopic herniorrhaphy has the advantage of facilitating simultaneous diagnosis and surgical intervention.

Analysis of the Summer Season Home Range of Domestic Feral Cats ( Felis catus ) - Focused on the Surroundings of Rural and Suburban Areas.

In order to analyze the home range of feral cats residing in the surroundings of rural and suburban areas, we collected coordination information data from five feral cats. As a result of such research, 100% MCP was defined as minimum 31,500 and maximum 351,900, and 95% KR was defined as minimum 9,400 and maximum 502,800, 75% KR was defined as minimum 3,600 and maximum 126,900, and 50% MCP was defined as minimum 1,800 and maximum 51,700. The home range of feral cats was also analyzed during daytime and nighttime, and all five individuals showed a wider home range during the nighttime than daytime. The analysis of gender shows that the average home range of female feral cats is larger than the average of males. Meanwhile, the results of information data with wide-open areas such as farm land and terrace land on the river showed that the analyzed value was increased generally, and showed variable values depending on the gender and size of each individual feral cat.

Polymer photovoltaic cell embedded with p-type single walled carbon nanotubes fabricated by spray process.

In the current study, we fabricated polymer (poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl-C(61) butyric-acid methyl-ester (PCBM) blend) photovoltaic (PV) cells embedded with p-type single walled carbon nanotubes (SWCNTs) with tangled hair morphology. The power conversion efficiency (PCE) rapidly increased with SWCNT concentration of up to 6.83% coverage, and then decreased and saturated with increasing SWCNT concentration; i.e., the PCE peaks at 5.379%. This tendency is mainly associated with hole transport efficiency toward the transparent electrode (indium-tin-oxide (ITO)) via SWCNTs, directly determining the series resistance and shunt resistance of the polymer PV cells embedded with SWCNTs: the PV cell is increasing shunt resistance and decreasing series resistance.

Indication of endoscopic retrograde cholangiography by noninvasive predictive factors of common bile duct stones before laparoscopic cholecystectomy: a prospective clinical study.

PURPOSE: To evaluate the reliability of a screening method in patients with common bile duct (CBD) stones before laparoscopic cholecystectomy (LC) based on predictive factors, and to determine the cases for which preoperative therapeutic endoscopic retrograde cholangiography (ERC) is indicated. MATERIALS AND METHODS: Alkaline phosphatase, total bilirubin, amylase, and dilation of CBD results were defined as predictive factors for CBD stones. In cases in which all these 4 factors were negative, preoperative ERC was omitted, and in cases in which 1 of the 4 factors was positive, ERC was performed before LC. RESULTS: A total of 323 patients (83.7%) in whom all 4 factors were negative, ERC was omitted. In all the 63 patients (16.3%) in whom 1 of the 4 factors was positive, ERC was performed. In 52 (82.5%) of them, CBD stones were present and in 43 of them, LC was performed after endoscopic choledocholithotomy. CONCLUSIONS: For cases in which any 1 of the 4 factors was positive before LC, it was strongly recommended to perform preoperative ERC.

Sympathomodulatory effects of Saam acupuncture on heart rate variability in night-shift-working nurses.

OBJECTIVE: We assessed the effects of Saam (traditional Korean) acupuncture on the autonomic nervous system in night-shift nurses using power-spectral heart-rate variability (HRV) analysis. METHODS: This study had a 2 × 4 cross-over design with a series of six (n = 1) controlled trials. Six night-shift nurses were randomly divided into two groups, and each nurse received four acupuncture treatments on the third day of night-shift work. One group started with Saam acupuncture (gallbladder jeonggyeok), while the other started with sham acupuncture. Saam acupuncture and sham acupuncture were applied in turn. HRV was measured before and after treatment. For statistical analysis, the results of the two groups were combined, and a Bayesian model was used to compare the changes in HRV values before and after treatment, between Saam and sham acupuncture. RESULTS: As the ratio of low- to high-frequency power (LF/HF) for HRV increased on the third day of night-shift work in the pilot study, HRV measurements were made on the third day. Compared with sham acupuncture, Saam acupuncture reduced sympathetic activity; the overall median treatment effect estimate in LF normalised units decreased by -17.4 (confidence interval (CI): -26.67, -8.725) and that for LF/HF decreased by -1.691 (CI: -3.222, -0.3789). The overall median treatment effect estimate in HF normalised units increased by 17.41 (CI: 6.393, 27.13) with Saam acupuncture, suggesting an increase in parasympathetic activity. CONCLUSION: Saam acupuncture may attenuate the imbalance between sympathetic and parasympathetic activities induced by night-shift work in nurses.

[Efficacy of hepatic arterial infusion chemotherapy with cisplatin for advanced hepatocellular carcinoma].

BACKGROUND: Transcatheter arterial chemoembolization (TACE) was performed as the initial therapy for advanced hepatocellular carcinoma (HCC). However, no effective chemotherapy has been established for patients who did not respond to TACE, and for those the therapy was not suitable. Since 2004, transcatheter arterial infusion (TAI) chemotherapy using fine-powder cisplatin has been applied at our department to such cases mentioned before. This report described the therapeutic results of TAI therapy and presented a case of HCC accompanied by portal vein tumor thrombus (PVTT) for which the therapy was effective. PATIENTS AND METHODS: TAI was performed using cisplatin in 16 patients with inoperable advanced HCC between 2004 and 2010. Cisplatin was infused into the proper hepatic artery at a dose of 65 mg/m2 for 30 minutes. RESULTS: TAI was performed in each patient 1.8 times on average, ranging from 1 to 8 times. Therapeutic Effect 4 (TE4) was obtained in 1 case, TE3 in 2, TE2 in 1, and TE1 in 11 cases. The only severe adverse event rated as grade 3 or above during the study were nausea and anorexia reported in 6.3% of the patients, and adverse events rated as less than grade 2 were increased serum hepato-biliary enzyme levels in 68.8%, nausea in 68.8% of the patients. The overall 1-year survival rate was 31.2%, and the 50% survival period was 314 days. CONCLUSION: As a treatment option following the initial TACE therapy for advanced HCC, TAI using cisplatin can improve the prognosis of HCC.

[Two cases of advanced hepatocellular carcinoma with portal vein tumor thrombus responding to transcatheter arterial infusion chemotherapy using cisplatin].

We report two cases of advanced hepatocellular carcinoma( HCC) with a portal vein tumor thrombus (PVTT) responding to transcatheter arterial infusion chemotherapy (TAI) using cisplatin (CDDP). Case 1: A 65-year-old male patient was diagnosed with unresectable multiple HCCs. After 5 courses of transcatheter arterial chemoembolization (TACE), the tumor became markedly enlarged, and a PVTT (Vp2) and lymph node metastasis were noted. TAI was conducted as the second- line chemotherapy, and the liver tumor, PVTT, and lymph node metastasis shrank. The clinical response was rated as a partial response (PR). Case 2: A 72-year-old female patient was diagnosed with single HCC. After a course of TACE, the tumor became markedly enlarged and was accompanied by a PVTT (Vp4). TAI was performed as the second-line chemotherapy, and the liver tumor and PVTT significantly shrank. The clinical response was also rated as a PR. TAI using CDDP as the second-line chemotherapy for advanced HCC is a promising treatment likely to contribute to the improvement of the patient's prognosis.

Carcinoma of the ampulla of vater arising from the peribiliary gland.

The present paper reported a case of a carcinoma that probably developed from the peribiliary gland within the ampulla of Vater based on the histopathological findings of the resected specimens. A 49-year-old female became aware of epigastralgia and was diagnosis of stenosis of duodenal 2nd portion. There were no malignant findings on gastrointestinal endoscopy and computed thomography. Endoscopic retrograde cholangiopancreatography revealed no tumor in the main pancreatic duct or the common bile duct or ampulla of Vater. Pylorus preserving panctreaticoduodenectomy was performed with a diagnosis of duodenal stenosis of unknown cause. The histopathological findings revealed that a moderately to poorly differentiated adenocarcinoma originating near the peribiliary gland in the ampulla of Vater was extensively distributed in the submucosal layer of the duodenum. Based on these findings, a diagnosis of a carcinoma of the ampulla of Vater arising from the peribiliary gland was most likely suspected. Judging from the generally known development and extension of carcinoma of the ampulla of Vater, the current case appeared to be a very rare one.

The fabrication and characterization of organic light-emitting diodes using transparent single-crystal Si membranes.

For applications such as solar cells and displays, transparent single-crystal Si membranes were fabricated on a silicon-on-insulator (SOI) wafer. The SOI wafer included a buried layer of SiO2 and Si3N4 as an etch-stop layer. The etch-stop layer enabled fabrication of transparent single-crystal Si membranes with various thicknesses, and the thinning technology is described. For membranes with thicknesses of 18, 72 and 5000 nm, the respective optical transparent were 96.9%, 93.7% and 9% for R (red, lambda = 660 nm), 96.9%, 91.4% and 1% for G (green, lambda = 525 nm), and 97.0%, 93.2% and 0% for B (blue, lambda = 470 nm). Organic light-emitting diodes (OLEDs) were then fabricated on transparent single-crystal Si membranes with various top Si thicknesses. OLEDs fabricated on 18, 72 and 5000 nm thick membranes and operated at 6 V demonstrated a luminance of 1350, 443 and 27 cd m(-2) at the current densities of 148, 131 and 1.5 mA cm(-2), respectively.

The effect of donor layer thickness on the power conversion efficiency of organic photovoltaic devices fabricated with a double small-molecular layer.

In organic photovoltaic (OPV) devices fabricated with a double small-molecular layer, the power conversion efficiency strongly depends on the thickness of the organic donor layer (here, copper phthalocyanine). In other words, the power conversion efficiency increases with the donor layer thickness up to a specific thickness ( approximately 12.7 nm) and then decreases beyond that thickness. This trend is associated with the light absorption and carrier transport resistance of the small-molecular donor layer, both of which strongly depend on the layer thickness. Experimental and calculated results showed that the short-circuit current due to light absorption increased with the donor layer thickness, while that due to current through the donor layer decreased with 1/R. Since the total short-circuit current is the product of the light absorption current and current through the donor layer, there is a trade-off, and the maximum power conversion efficiency occurs at a specific organic donor layer thickness (e.g. approximately 12.7 nm in this experiment).

Distinctive expression and function of four GSDM family genes (GSDMA-D) in normal and malignant upper gastrointestinal epithelium.

Gasdermin (GSDM or GSDMA), expressed in the upper gastrointestinal tract but frequently silenced in gastric cancers (GCs), regulates apoptosis of the gastric epithelium. It has three human homologs, GSDMB, GSDMC, and GSDMD (GSDM family) and they are considered to be involved in the regulation of epithelial apoptosis but not yet known. We investigated the expression pattern of the family genes in the upper gastrointestinal epithelium and cancers. Reverse transcriptase-polymerase chain reaction revealed that, unlike GSDMA expressed in differentiated cells, GSDMB is expressed in proliferating cells and GSDMD in differentiating cells. GSDMC, meanwhile, is expressed in both differentiating and differentiated cells. Colony formation assay showed that GSDMB, closely related to GSDMA, has no cell-growth inhibition activity in gastric cancer cells, and that GSDMC and GSDMD, respectively, exhibit the activity with different strengths from that of GSDMA. Expression analyses of the four family genes in esophageal and GCs suggested that GSDMC and GSDMD as well as GSDMA are tumor suppressors and that GSDMB, which was amplified and overexpressed in some GCs, could be an oncogene. The results of the expression analysis and colony formation assay suggest that each family gene may have a distinct function in the upper gastrointestinal epithelium.