Bosonic Structure of a 2-Dimensional Fermion Model with Interaction among Different Speices

We study a massive Thirring-like model in 2-dimensional space-time, which contains two different species of fermions. This model is a field theoretical version of the quantum mechanical model originally proposed by Gl\"{o}ckle, Nogami and Fukui, where different fermions interact with each other through $\delta$-function potentials. We derive a corresponding boson model by the bosonization technique in the path integral formulation. This is a simple but non-trivial extension of the freedom of the bosonization technique. Operator correspondences between fermion and boson fields are given. One of these could not be realistically expected from the naive correspondence of the original single-species models. It is essential for this point that in our model fermions of the same kind do not interact with each other directly. We find that for a specific value of the coupling constant, one boson field becomes free while the other is a Sine-Gordon field. For this case, therefore, our two-species model is equivalent to the ordinary Sine-Gordon model of a single boson field.Comment: Latex file, 11pages, no figure, needs ptptex.st

Unlocking the Full Potential of Polymer-Based Solid-State Photon Upconversion

To harvest the full potential of polymer-based solid-state photon upconversion (UC) devices, we examined the effect of the molecular weight of a fluorescent polymer on the UC efficiency. With a high-molecular-weight polymer, a long triplet lifetime of 11.2 ms was achieved, which led to a characteristic threshold intensity of 67 mW cm⁻², considerably lower than those of previously reported polymer-based UC devices. Furthermore, the external quantum efficiency of our UC device was as high as ∼0.35%. Consequently, fluorescent conjugated polymers with long triplet lifetimes can serve as attractive candidates for efficient solid-state UC devices

Sensitizer–host–annihilator ternary-cascaded triplet energy landscape for efficient photon upconversion in the solid state

In this paper, we introduce a new strategy for improving the efficiency of upconversion emissions based on triplet–triplet exciton annihilation (TTA-UC) in the solid state. We designed a ternary blend system consisting of a triplet sensitizer (TS), an exciton-transporting host polymer, and a small amount of an annihilator in which the triplet-state energies of the TS, host, and annihilator decrease in this order. The key idea underpinning this concept involves first transferring the triplet excitons generated by the TS to the host and then to the annihilator, driven by the cascaded triplet energy landscape. Because of the small annihilator blend ratio, the local density of triplet excitons in the annihilator domain is higher than those in conventional binary TS/annihilator systems, which is advantageous for TTA-UC because TTA is a density-dependent bimolecular reaction. We tracked the triplet exciton dynamics in the ternary blend film by transient absorption spectroscopy. Host triplet excitons are generated through triplet energy transfer from the TS following intersystem crossing in the TS. These triplet excitons then diffuse in the host domain and accumulate in the annihilator domain. The accumulated triplet excitons undergo TTA to generate singlet excitons that are higher in energy than the excitation source, resulting in UC emission. Based on the excitation-intensity and blend-ratio dependences of TTA-UC, we found that our concept has a positive impact on accelerating TTA

Triplet sensitization via charge recombination at organic heterojunction for efficient near-infrared to visible solid-state photon upconversion

Realizing efficient near-infrared to visible photon upconversion in the solid state is pivotal for commercial applications in various fields. We previously reported a solid-state upconversion device which imitated the photovoltaic conversion mechanisms of organic solar cells. This leads to a significant improvement of up to 2.3% in the external quantum efficiency, which is two orders of magnitude higher than that of conventional devices. Here, we investigate the upconversion mechanism of this device. We examine exciton and charge dynamics using transient absorption spectroscopy and find that approximately 67% of incident photons are utilized owing to fast singlet exciton diffusion in the nonfullerene acceptor layer. Strikingly, triplet excitons are accumulated near the donor/acceptor interface, enabling accelerated triplet–triplet annihilation by a factor of more than 10

Antireflux Metal Stent for Initial Treatment of Malignant Distal Biliary Obstruction

Objectives. To compare the use of an antireflux metal stent (ARMS) with that of a conventional covered self-expandable metal stent (c-CSEMS) for initial stenting of malignant distal biliary obstruction (MDBO). Materials and Methods. We retrospectively investigated 59 consecutive patients with unresectable MDBO undergoing initial endoscopic biliary drainage. ARMS was used in 32 patients and c-CSEMS in 27. Technical success, functional success, complications, causes of recurrent biliary obstruction (RBO), time to RBO (TRBO), and reintervention were compared between the groups. Results. Stent placement was technically successful in all patients. There were no significant intergroup differences in functional success (ARMS [96.9%] versus c-CSEMS [96.2%]), complications (6.2 versus 7.4%), and RBO (48.4 versus 42.3%). Food impaction was significantly less frequent for ARMS than for c-CSEMS (P=0.037), but TRBO did not differ significantly between the groups (log-rank test, P=0.967). The median TRBO was 180.0 [interquartile range (IQR), 114.0–349.0] days for ARMS and 137.0 [IQR, 87.0–442.0] days for c-CSEMS. In both groups, reintervention for RBO was successfully completed in all patients thus treated. Conclusion. ARMS offers no advantage for initial stent placement, but food impaction is significantly prevented by the antireflux valve

A deep learning algorithm to translate and classify cardiac electrophysiology

The development of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) has been a critical in vitro advance in the study of patient-specific physiology, pathophysiology, and pharmacology. We designed a new deep learning multitask network approach intended to address the low throughput, high variability, and immature phenotype of the iPSC-CM platform. The rationale for combining translation and classification tasks is because the most likely application of the deep learning technology we describe here is to translate iPSC-CMs following application of a perturbation. The deep learning network was trained using simulated action potential (AP) data and applied to classify cells into the drug-free and drugged categories and to predict the impact of electrophysiological perturbation across the continuum of aging from the immature iPSC-CMs to the adult ventricular myocytes. The phase of the AP extremely sensitive to perturbation due to a steep rise of the membrane resistance was found to contain the key information required for successful network multitasking. We also demonstrated successful translation of both experimental and simulated iPSC-CM AP data validating our network by prediction of experimental drug-induced effects on adult cardiomyocyte APs by the latter

Impact of Hepatitis Virus on the Feasibility and Efficacy of Anticancer Agents in Patients With Hepatocellular Carcinoma in Phase I Clinical Trials

Chronic viral hepatitis is a risk factor for liver fibrosis and hepatocellular carcinoma (HCC). Patients with advanced HCC have limited effective therapeutic options and are considered potential candidates for early phase clinical trials of anti-cancer agents. The impact of chronic viral hepatitis on the efficacy of anticancer agents for patients with HCC in phase I trials (P-Is) still remains unclear and has not been reported. We retrospectively analyzed the outcomes of consecutive HCC patients in P-Is conducted in a single institute, focusing on chronic viral hepatitis. Of 85 patients enrolled in P-Is, 46 (54%) patients positive and 39 (46%) patients negative for chronic viral hepatitis showed no significant difference in clinical and laboratory variables and on the point of the best response based on the Response Evaluation Criteria in Solid Tumors (RECIST) criteria; moreover, the frequency of Grade ≥3 adverse events (AE) was not significantly different. The median time to treatment failure (TTF) and overall survival (OS) from the P-I enrolment were 2.0 and 13.7 months, respectively. No patient experienced reactivation of hepatitis B virus (HBV) or treatment-related death. Chronic viral hepatitis does not independently affect the outcomes of anticancer drugs. Advanced HCC patients with chronic viral hepatitis could be feasible for P-Is

Investigation of drugs for the prevention of doxorubicin-induced cardiac events using big data analysis

Aim: Doxorubicin, an anthracycline anti-tumour agent, is an essential chemotherapeutic drug; however, the adverse events associated with doxorubicin usage, including cardiotoxicity, prevent patients from continuing treatment. Here, we used databases to explore existing approved drugs with potential preventative effects against doxorubicin-induced cardiac events and examined their efficacy and mechanisms. Methods: The Gene Expression Omnibus (GEO), Library of Integrated Network-based Cellular Signatures (LINCS), and Food and Drug Administration Adverse Events Reporting System (FAERS) databases were used to extract candidate prophylactic drugs. Mouse models of doxorubicin-induced cardiac events were generated by intraperitoneal administration of 20 mg/kg of doxorubicin on Day 1 and oral administration of prophylactic candidate drugs for 6 consecutive days beginning the day before doxorubicin administration. On Day 6, mouse hearts were extracted and examined for mRNA expression of apoptosis-related genes. Results: GEO analysis showed that doxorubicin administration upregulated 490 genes and downregulated 862 genes, and LINCS data identified sirolimus, verapamil, minoxidil, prednisolone, guanabenz, and mosapride as drugs capable of counteracting these genetic alterations. Examination of the effects of these drugs on cardiac toxicity using FAERS identified sirolimus and mosapride as new prophylactic drug candidates. In model mice, mosapride and sirolimus suppressed the Bax/Bcl-2 mRNA ratio, which is elevated in doxorubicin-induced cardiotoxicity. These drugs also suppressed the expression of inflammatory cytokines Il1b and Il6 and markers associated with myocardial fibrosis, including Lgal3 and Timp1. Conclusion: These findings suggest that doxorubicin-induced cardiac events are suppressed by the administration of mosapride and sirolimus

Solitary Peutz-Jeghers type hamartomatous polyps in the duodenum are not always associated with a low risk of cancer: two case reports

INTRODUCTION: A hamartomatous polyp without associated mucocutaneous pigmentation or a family history of Peutz-Jeghers Syndrome is diagnosed as a solitary Peutz-Jeghers type hamartomatous polyp. As compared with Peutz-Jeghers Syndrome, Peutz-Jeghers type hamartomatous polyps are diagnosed with a lower risk of cancer and are regarded as a different disorder. CASE PRESENTATION: In case one, we describe an 84-year-old Japanese man with a 14 mm duodenal polyp. Endoscopic mucosal resection was performed and histological examination showed findings suggestive of a hamartomatous polyp with a focus of well-differentiated adenocarcinoma. In case two, we describe a 76-year-old Japanese man who had been treated for prostate, rectal and lung cancer. Upper gastrointestinal endoscopy revealed a duodenal polyp measuring 15 mm in diameter. Endoscopic mucosal resection was performed, and histological examination showed findings suggestive of a hamartomatous polyp. Liver and thyroid cancers were found after the endoscopic treatment. CONCLUSION: Although duodenal solitary hamartomatous polyps are associated with a lower risk of cancer, four patients, including our cases, have been diagnosed with cancerous polyps. Patients with duodenal solitary hamartomatous polyps should be treated by endoscopic or surgical resection and need whole-body screening

Early effects of oral administration of lafutidine with mosapride compared with lafutidine alone on intragastric pH values

<p>Abstract</p> <p>Background</p> <p>The ideal medication for treatment of acid related diseases should have a rapid onset of action to promote hemostasis and resolution of symptoms. The aim of our study was to investigate the inhibitory effects on gastric acid secretion after a single oral administrations of lafutidine, is a newly synthesized H2-receptor antagonist, with mosapride 5 mg or lafutidine alone.</p> <p>Methods</p> <p>Ten <it>Helicobacter pylori </it>negative male subjects participated in this randomized, two-way crossover study. Intragastric pH was monitored continuously for 4 hours after a single oral administration of lafutidine 10 mg or lafutidine 10 mg with mosapride 5 mg (the lafutidine being administrated one hour after the mosapride). Each administration was separated by a 7-day washout period.</p> <p>Results</p> <p>The average pH during the 4-hour period after administration of lafutidine 10 mg with mosapride 5 mg was higher than after lafutidine 10 mg alone (median: 5.25 versus 4.58, respectively; <it>p </it>= 0.0318). During the 3–4 hour study period, lafutidine 10 mg with mosapride 5 mg provided a higher pH, compared to lafutidine 10 mg alone (median: 7.28 versus 6.42; <it>p </it>= 0.0208).</p> <p>Conclusion</p> <p>In <it>H. pylori </it>negative healthy male subjects, an oral dose of lafutidine 10 mg with mosapride 5 mg more rapidly increased intragastric pH than lafutidine 10 mg alone.</p