Effect of direct oral anticoagulant therapy on pulmonary artery clot dissolution in intermediate high-risk pulmonary thromboembolism.

BACKGROUND: Direct oral anticoagulants are the established drugs for treating pulmonary thromboembolism. The advantage of direct oral anticoagulants over conventional therapy for clot lysis and right ventricular unloading in the acute phase remains unclear. This study aimed to evaluate the effect of acute treatment with direct oral anticoagulants on clot dissolution and right ventricular unloading in intermediate high-risk pulmonary thromboembolism. METHODS: Thirty patients with intermediate high-risk pulmonary thromboembolism admitted between November 2012 and December 2018 were included; 21 and 9 were treated with direct oral anticoagulants and conventional therapy, respectively. We compared the efficacy of clot dissolution and right ventricular unloading for intermediate high-risk pulmonary thromboembolism between direct oral anticoagulant and conventional therapy in the acute phase. Efficacy was assessed by computed tomography obstruction index, right/left ventricular ratio, and brain natriuretic peptide levels between baseline and at discharge. RESULTS: Computed tomography obstruction index, right ventricular/left ventricular ratio, and brain natriuretic peptide levels were significantly lower at discharge than at admission in both groups. The rate of improvement in computed tomography obstruction index was significantly higher in the direct oral anticoagulant therapy group than in the conventional therapy group (64 ± 15% vs. 47 ± 16%; p = 0.01). There were no significant differences in the rate of improvement in right ventricular/ left ventricular ratio and brain natriuretic peptide levels between the two groups. CONCLUSIONS: Compared with conventional therapy, direct oral anticoagulants significantly reduced pulmonary artery clot burden conventional therapy in the acute treatment of intermediate high-risk pulmonary thromboembolism.

Risk stratification of synchronous gastric cancers including alcohol-related genetic polymorphisms.

BACKGROUND AND AIM: We previously identified that ever-smoking and severe gastric atrophy in pepsinogen are risk factors for synchronous gastric cancers (SGCs). This study aimed to determine the association of alcohol drinking status or alcohol-related genetic polymorphism with SGCs and also stratify their risk. METHODS: This multi-center prospective cohort study included patients who underwent endoscopic submucosal dissection for the initial early gastric cancers at 22 institutions in Japan. We evaluated the association of alcohol drinking status or alcohol dehydrogenase 1B (ADH1B) and acetaldehyde dehydrogenase 2 (ALDH2) genotypes with SGCs. We then stratified the risk of SGCs by combining prespecified two factors and risk factors identified in this study. RESULTS: Among 802 patients, 130 had SGCs. Both the ADH1B Arg and ALDH2 Lys alleles demonstrated a significant association with SGCs on multivariate analysis (odds ratio, 1.77), although alcohol drinking status showed no association. The rates of SGCs in 0-3 risk factors in the combined evaluation of three risk factors (ever-smoking, severe gastric atrophy in pepsinogen, and both the ADH1B Arg and ALDH2 Lys alleles) were 7.6%, 15.0%, 22.0%, and 32.1%, respectively. The risk significantly increased from 0 to 3 risk factors on multivariate analysis (P for trend <0.001). CONCLUSIONS: Both the ADH1B Arg and ALDH2 Lys alleles were at high risk for SGCs. The risk stratification by these three factors may be a less invasive and promising tool for predicting their risk.

Secret key rates for intensity-modulated dual-threshold detection key distribution under individual beam splitting attacks.

We investigate the secret key rates for the recently proposed intensity-modulated dual-threshold key distribution [T. Ikuta and K. Inoue, New J. Phys. 18 (2016)] under beam splitting attacks. We show that previous assumptions on an eavesdropper that performs hard decision measurements on the channel, overestimates the secret key rate. We discuss the impact of an eavesdropper that can measure full soft information and give the secret key rates under forward and reverse reconciliation. Further, we perform simulations for different system assumptions and show the optimal modulation depths for these systems. We also outline an attack on this protocol based on photon counting that prohibits secret key generation.

Free space optical secret key agreement.

Free space optical (FSO) communications are enabling high-speed global wireless networks. Thanks to the highly directional nature of laser beam, they also yield a greater security advantage over radio frequency counterparts. When combined with a scheme of secret key agreement (SKA), FSO-SKA can establish at high speed a symmetric secret key which cannot be decrypted even by unbounded computer resources. Although there have been many theoretical studies on SKA, experimental investigations have been quite lacking, especially on quantifying eavesdropping risks and secret key rates in realistic environment. Here, we report the first full-field implementations of FSO-SKA in a 7.8-km terrestrial link with a probing station, enabling the estimation of eavesdropping risks. We attain the final key rates from 100 kbps to 7.77 Mbps under various atmospheric and beaming conditions even with total losses of 55dB or higher, in which known quantum key distribution schemes attain impractically low key rates.

Free-space optical wiretap channel and experimental secret key agreement in 7.8 km terrestrial link.

Secret key agreement using physical properties of a wireless channel is becoming a promising scheme to establish a secret key between two users, especially in short-distance radio frequency (RF) communications. In this scheme, the existence of codes or key distillation that can make the leaked information to an eavesdropper arbitrarily small can be derived in an information theoretical way, given a priori knowledge on the channel linking a sender (Alice), a legitimate receiver (Bob), and an eavesdropper (Eve), which is called the wiretap channel. In practice, however, it is often difficult for Alice and Bob to get sufficient knowledge on Eve. In this study, we implement a free-space optical wiretap channel in a 7.8 km-terrestrial link and study how to estimate Eve's tapping ability, demonstrating high speed secret key agreement in the optical domain under a certain restricted condition of line-of-sight.

From Linear to Nonlinear Responses of Thermal Pure Quantum States.

We propose a self-validating scheme to calculate the unbiased responses of quantum many-body systems to external fields of arbitrary strength at any temperature. By switching on a specified field to a thermal pure quantum state of an isolated system, and tracking its time evolution, one can observe an intrinsic thermalization process driven solely by many-body effects. The transient behavior before thermalization contains rich information on excited states, giving the linear and nonlinear response functions at all frequencies. We uncover the necessary conditions to clarify the applicability of this formalism, supported by a proper definition of the nonlinear response function. The accuracy of the protocol is guaranteed by a rigorous upper bound of error exponentially decreasing with system size, and is well implemented in the simple ferromagnetic Heisenberg chain, whose response at high fields exhibits a nonlinear band deformation. We further extract the characteristic features of excitation of the spin-1/2 kagome antiferromagnet; the wave-number-insensitive linear responses from the possible spin liquid ground state, and the significantly broad nonlinear peaks which should be generated from numerous collisions of quasiparticles, that are beyond the perturbative description.

The Risk Factors for Metastasis in Non-Ampullary Duodenal Neuroendocrine Tumors Measuring 20 mm or Less in Diameter.

BACKGROUND/AIMS: The treatment strategy for non-ampullary duodenal neuroendocrine tumors (NAD-NETs) ≤20 mm in diameter has not been established. In this study, we aimed to evaluate the detailed characteristics of NAD-NETs ≤20 mm in diameter to clarify the risk factors of subsequent metastasis. METHODS: The patients with NAD-NETs ≤20 mm in diameter who had been treated at 12 institutions between 1992 and 2013 were enrolled. Clinical records were retrieved, and histopathological findings of all cases were centrally reviewed by 2 pathologists. RESULTS: We studied 49 patients with a mean follow-up period of 66.5 months. Thirty-five patients were initially treated with endoscopic resection (ER), and 14 with surgery. A univariate analysis revealed the ORs and 95% CIs of the risk factors for metastasis were lymphovascular invasion (12.5 [2.01-77.9]), multiple tumors (9.75 [1.46-65.4]), a tumor size of 11-20 mm (6.67 [1.21-36.6]), and World Health Organization grade G2 (7.13 [1.16-43.9]). Five-year overall and disease-specific survival rates were 86.1 and 97.2%, respectively. CONCLUSION: This is the first study to demonstrate the risk factors of metastasis in NAD-NETs ≤20 mm in diameter. These findings may be helpful for determining the appropriate therapeutic approach and the clinical strategy of treatment following ER.

Free-space optical channel estimation for physical layer security.

We present experimental data on message transmission in a free-space optical (FSO) link at an eye-safe wavelength, using a testbed consisting of one sender and two receiver terminals, where the latter two are a legitimate receiver and an eavesdropper. The testbed allows us to emulate a typical scenario of physical-layer (PHY) security such as satellite-to-ground laser communications. We estimate information-theoretic metrics including secrecy rate, secrecy outage probability, and expected code lengths for given secrecy criteria based on observed channel statistics. We then discuss operation principles of secure message transmission under realistic fading conditions, and provide a guideline on a multi-layer security architecture by combining PHY security and upper-layer (algorithmic) security.

Suppressive expression of CD274 increases tumorigenesis and cancer stem cell phenotypes in cholangiocarcinoma.

Cholangiocarcinoma is an aggressive malignant tumor originating from intrahepatic or extrahepatic bile ducts. Its malignant phenotypes may be assumed by cancer stem cells (CSC). Here, we demonstrate that CD274 (PD-L1), known as an immunomodulatory ligand, has suppressive effects on CSC-related phenotypes of cholangiocarcinoma. Using two human cholangiocarcinoma cell lines, RBE and HuCCT1, we attempted to isolate the CD274(low) and CD274(high) cells from each cell line, and xenografted them into immunodeficient NOD/scid/γcnull (NOG) mice. We found that the CD274(low) cells isolated from both RBE and HuCCT1 are highly tumorigenic in NOG mice compared with CD274(high) cells. Furthermore, the CD274(low) cells possess several CSC-related characteristics, such as high aldehyde dehydrogenase (ALDH) activity, reduced reactive oxygen species production and a dormant state in the cell cycle. Furthermore, depletion of CD274 expression by shRNA in RBE cells enhances their tumorigenicity and increases ALDH activity. These findings are compatible with our observation that clinical cholangiocarcinoma specimens are classified into low and high groups for CD274 expression, and the CD274 low group shows poorer prognosis when compared with the CD274 high group. These results strongly suggest that CD274 has a novel function in the negative regulation of CSC-related phenotypes in human cholangiocarcinoma, which is distinct from its immunomodulatory actions.

Comparison of the long-term outcomes of endoscopic resection for superficial squamous cell carcinoma and adenocarcinoma of the esophagus in Japan.

OBJECTIVES: Few studies have simultaneously evaluated the long-term outcomes of endoscopic resection (ER) for squamous cell carcinoma (SCC) and adenocarcinoma (AC) of the esophagus in Japan. The objective of this study was to evaluate the long-term outcomes of ER for superficial esophageal cancer in consecutive patients. METHODS: This was a retrospective study from a single institution. From April 2001 to June 2012, 204 patients with SCC and 26 patients with AC were included from a total of 355 consecutive patients who were treated by esophageal ER at the Tohoku University Hospital. Patients with submucosal invasion deeper than 200 µm and lymphovascular involvement were excluded. The intervention followed was endoscopic therapy. RESULTS: Overall survival, disease-free survival, and recurrence rates were evaluated as long-term outcomes. In the SCC group, during the median observation time of 36.5 months (range, 6-120 months), 22 (10.8%) patients experienced metachronous recurrence, 4 (2.0%) patients experienced local recurrence, and 27 (13.2%) patients died from causes unrelated to SCC. In the AC group, during the median observation time of 45.5 months (range, 6-131 months), one patient (3.8%) experienced metachronous recurrence and two (7.7%) died from causes unrelated to AC. The cumulative 5-year overall survival rates were not significantly different between SCC (75.9%) and AC (88.9%) (P=0.120). The cumulative 5-year disease-free survival rates of SCC (57.1%) were significantly lower than those of AC (85.2%; P=0.017). The cumulative 5-year recurrence rates of SCC (32.0%) were significantly higher than those of AC (4.2%; P=0.023). CONCLUSIONS: The rate of recurrence after ER was higher in patients with SCC than that in patients with AC. These findings suggest that, by detecting AC of the esophagus earlier, a satisfactory prognosis without recurrence can be expected after ER in Japan, and more rigorous endoscopic follow-up is necessary after ER in patients with SCC than in those with AC.

Calcium carbonate breath test for non-invasive estimation of gastric acid secretion.

Gastric acid measurement is useful in assessing the effectiveness of antisecretory drugs, however, the conventional tests involve invasive nasogastric intubation. Orally administered ¹³C-labeled calcium carbonate (Ca¹³CO3) reacts with gastric acid to produce ¹³C-labeled carbon dioxide (¹³CO2), which is then excreted in the breath. The objective of this study was to evaluate the suitability of Ca¹³CO3 breath test for estimating gastric acid secretion in human noninvasively. First, the Ca¹³CO3 breath test and the measurement of pooled gastric acid under a fasting condition were performed in 6 healthy volunteers to evaluate the correlation between the two parameters. Next, endoscopic gastric acid collection and the Ca¹³CO3 breath test were performed on different days after pentagastrin injection in 20 subjects to evaluate the correlation between the tests and the reproducibility. Finally, the same studies were repeated in 4 subjects before and after 1-week rabeprazole, a proton pump inhibitor, administration. The maximum CO2 concentration (Cmax) correlated very well with the amount of pooled gastric acid (r = 0.95), suggesting that Ca¹³CO3 breath test values well reflected the fasting intragastric acidity. The ¹³CO2 concentration after pentagastrin injection correlated well with pentagastrin-stimulated maximal acid output (r = 0.79 at 20 min). The reproducibility of the Ca¹³CO3 breath test under pentagastrin-stimulation was good (coefficient of variation = 0.11). Rabeprazole administration markedly reduced the values of the Ca¹³CO3 breath test, suggesting that it can sensitively assess the efficacy of rabeprazole. The Ca¹³CO3 breath test can potentially be a useful method for non-invasive estimation for gastric acid secretion in human.

Endoscopically proven case of rapid esophagogastric variceal progression and rupture as a result of portal hypertension with liver sarcoidosis.

Sarcoidosis is a multi-systemic disease of unknown etiology that results in the development of non-caseating epithelioid granulomas. The liver is the third most frequently involved organ after the lymph nodes and the lungs. Most cases of liver sarcoidosis do not present with symptoms and involve minimal liver dysfunction, but some cases display progression to portal hypertension and liver cirrhosis, and finally to liver failure. The mechanism and the risk of progression in liver sarcoidosis are still unknown because of the diagnostic difficulty associated with this condition, and because follow-up examinations can only be done in an invasive manner. Here, we present an informative case of liver sarcoidosis with rapid progression of esophagogastric varices. Four months prior to the definitive diagnosis, no signs of varices were observed on endoscopy, and developmentof esophagogastric varices, rapid progression, and eventual rupture occurred in a short period of time. A liver biopsy, carried out after endoscopic sclerotherapy, revealed that granulomas primarily affected the portal area without fibrotic and cirrhotic changes, which is considered a primary cause of portal hypertension and esophagogastric varices. Following the liver biopsy, the patient was given systemic steroids and is currently receiving outpatient care. Thus, we should consider the possibility that liver sarcoidosis, even in the absence of cirrhotic changes, can cause serious events such as esophagogastric variceal rupture following rapid progression as a result of portal hypertension.

Gender differences in oesophageal mucosal injury in a reflux oesophagitis model of rats.

OBJECTIVE: There is a strong male predominance of oesophageal adenocarcinoma, which might be related to the higher prevalence of precursor lesions such as erosive reflux oesophagitis in men compared with women. This experiment investigated the gender difference in a reflux oesophagitis model of rats and explored the potential role of oestrogen in controlling oesophageal tissue damage. DESIGN: An acid-reflux oesophagitis model was surgically produced in male and female rats, and ascorbic acid in the diet and sodium nitrite in the drinking water were administered to half of either group to provoke luminal exogenous nitric oxide (NO) as an exacerbating agent. Seven days after the surgery, the oesophagus was excised, and the injury area, myeloperoxidase activity and pro-inflammatory cytokine levels were measured. Furthermore, 17ß-oestradiol was administered to ovariectomised female rats or male rats, which then underwent reflux oesophagitis surgery. RESULTS: While there was no gender difference in oesophageal damage in the baseline model, oesophageal damage was more intensively observed in males than in females in the presence of exogenous NO administration. While oesophageal damage was increased in ovariectomised rats compared with sham ovariectomised, exacerbated oesophageal damage was attenuated by the replacement of 17ß-oestradiol. In addition, exacerbated oesophageal damage in male rats was suppressed by 17ß-oestradiol. CONCLUSION: This is the first study showing the prominent gender difference in the severity of oesophageal tissue damage in a gastro-oesophageal reflux disease-related animal model, highlighting the critical involvement of oestrogen in controlling gastro-oesophageal reflux disease-related oesophageal epithelial injury.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary disease without pulmonary hypertension.

Balloon pulmonary angioplasty (BPA) is beneficial for patients with chronic thromboembolic pulmonary disease (CTEPD) with pulmonary hypertension (PH). However, the clinical benefit of BPA for the patients with CTEPD without PH remains unknown. In this study, we aimed to evaluate the efficacy, safety, and long-term outcomes of BPA in patients with CTEPD without PH. We retrospectively analyzed the data from 84 CTEPD patients with mean pulmonary artery pressure (mPAP) < 25 mmHg and 39 CTEPD patients with mPAP ≤ 20 mmHg (without PH). Among the 39 patients with CTEPD without PH, 14 underwent BPA (BPA-treated group), and the remaining 25 received no treatment (untreated group). In the patients with CTEPD without PH, BPA led to improvements in symptoms, pulmonary vascular resistance (3.6 ± 1.6 to 2.6 ± 1.1 Wood units, p < 0.001), peak oxygen consumption (16.1 ± 4.0 to 18.8 ± 4.3 mL/kg/min, p = 0.033), minute ventilation versus carbon dioxide production slope (41.4 ± 12.2 to 35.1 ± 6.7, p = 0.026), and mPAP/cardiac output slope (7.0 ± 2.6 to 4.4 ± 2.0 mmHg/L/min, p = 0.004) and facilitated the discontinuation of home oxygenation therapy, with no serious complications. Kaplan-Meier analysis showed no significant difference in all-cause mortality between the untreated and BPA-treated groups. BPA may be a safe treatment option for the patients with CTEPD without PH that can alleviate symptoms, improve exercise capacity, and facilitate weaning from home oxygen therapy. Further prospective randomized trials are needed to confirm these findings.

Prevalence and Clinical Characteristics of Heterozygous RNF213 p.Arg4810Lys Variant Carriers Diagnosed With Chronic Thromboembolic Pulmonary Hypertension.

BACKGROUND: Ring finger protein 213 (RNF213) p.Arg4810Lys is a susceptibility gene for moyamoya disease, peripheral pulmonary artery stenosis (PPS), and other vascular diseases and thrombosis. We investigated the prevalence and clinical characteristics of RNF213 variant carriers diagnosed with chronic thromboembolic pulmonary hypertension (CTEPH). METHODS AND RESULTS: We retrospectively analyzed the prevalence of the RNF213 p.Arg4810Lys variant in patients diagnosed with CTEPH (n=112) and PPS (n=10). Clinical and angiographic characteristics were evaluated between RNF213 variant carriers diagnosed with CTEPH and noncarriers with CTEPH and homozygous variant carriers with PPS. Eight heterozygous RNF213 p.Arg4810Lys variant carriers (7.1%) were identified among patients diagnosed with CTEPH, while 5 patients with PPS (50%) carried the homozygous variant. The clinical characteristics of heterozygous variant carriers with CTEPH were not remarkably different from those of noncarriers with CTEPH. All heterozygous variant carriers with CTEPH showed webs/bands lesions at the segmental/subsegmental level, with 75% showing distal tortuous vessels. None of the heterozygous variant carriers with CTEPH exhibited the string-of-beads pattern or elongated stenosis. Homozygous variant carriers with PPS showed the string-of-beads pattern, elongated stenosis, and distal tortuous vessels without webs/bands lesions. CONCLUSIONS: A subset of patients diagnosed with CTEPH (7.1%) carried the heterozygous RNF213 p.Arg4810Lys variant. Clinical and angiographic characteristics of heterozygous variant carriers were not remarkably different from those of noncarriers of CTEPH. However, both heterozygous variant carriers with CTEPH and homozygous variant carriers with PPS showed tortuous vessels on angiography.

Clinical outcomes of upfront combination therapy for portopulmonary hypertension.

Background: Limited data exists on upfront combination therapy for portopulmonary hypertension. We evaluated the clinical efficacy, long-term outcomes, and safety of upfront combination therapy in patients with portopulmonary hypertension. Methods: We performed a retrospective, single-center cohort study involving a final analysis of 33 consecutive patients diagnosed with portopulmonary hypertension who were taking pulmonary arterial hypertension-specific medication. We compared hemodynamic parameters, risk profiles, composite clinical worsening events, and safety between monotherapy (n = 23) and upfront combination therapy (n = 10). Results: Twenty-seven patients (82 %) were classified into the Child-Pugh A stage. The change ratios of pulmonary vascular resistance (-32 % vs. -57 %, P = 0.006) were significantly better with upfront combination therapy. Upfront combination therapy also showed significant improvement in risk profiles. Kaplan-Meier analysis showed that the composite event-free rate was significantly lower in patients who received upfront combination therapy than in those who received monotherapy (P = 0.016), although no statistical differences were observed in all-cause death. In the univariate Cox proportional hazards analysis, upfront combination therapy was a factor for decreasing composite clinical worsening outcomes (hazard ratio 0.190, 95 % confidence interval 0.042-0.854; P = 0.030). No significant hepatic impairments were observed over 2 years of follow-up in the upfront combination group. Conclusions: In patients with portopulmonary hypertension, upfront combination therapy significantly improved symptoms and short-term hemodynamics, and reduced long-term clinical worsening events without serious adverse effects. This study's findings suggest that patients with portopulmonary hypertension presenting with mild hepatic impairment benefit from upfront combination therapy.

Large noncoding RNA HOTAIR enhances aggressive biological behavior and is associated with short disease-free survival in human non-small cell lung cancer.

HOTAIR is one of long non-coding RNAs and its expression correlates with the prognosis and metastasis in various cancers. We showed that HOTAIR expression has an important role in the development of non-small cell lung cancer (NSCLC). In this study, we examined the expression of HOTAIR in 77 NSCLCs, their corresponding normal lung tissues and 6 brain metastases by quantitative real-time RT-PCR. High expression of HOTAIR (tumor/normal ratio ⩾2) was detected in 17 patients (22.1%) and was frequently found in patients with advanced stage, lymph node metastasis or lymph-vascular invasion and short disease free interval. Furthermore, brain metastases show significantly higher HOTAIR expression compared to primary cancer tissues. HOTAIR-expressing A549 cells showed induced cell migration and anchorage-independent cell growth in vitro. These results indicate the expression of HOTAIR enhanced the aggressive behavior of NSCLC cells.

Barrett's esophageal cancer in which magnifying narrow-band imaging was useful for diagnosing extension under the squamous epithelium.

A 36-year-old man complained of heartburn. Gastrointestinal endoscopies showed a reddish and slightly depressed lesion in the right-anterior wall of the esophagogastric junction. With white light imaging, the area of the adenocarcinoma under the squamous epithelium was difficult to detect, but a slightly flat, elevated lesion appeared in the area of adenocarcinoma under the squamous epithelium. With narrow-band imaging (NBI) in the area of the Barrett's esophageal cancer under the squamous epithelium, a slight, brownish change could be observed. In addition, with the magnifying technique, irregular mesh-like vessels were observed, suggesting the presence of differentiated adenocarcinoma under the squamous epithelium. The lesion was resected en bloc by endoscopic submucosal dissection, and Barrett's esophageal cancer under the squamous epithelium was histologically confirmed. In this case, NBI with magnifying endoscopy was very useful to diagnose the extension of Barrett's esophageal cancer under the squamous epithelium.