Ion-Conducting Dynamic Solid Polymer Electrolyte Adhesives

Cross-linked polymer electrolytes containing structurally dynamic disulfide bonds have been synthesized to investigate their combined ion transport and adhesive properties. Dynamic network polymers of varying cross-link densities are synthesized via thiol oxidation of a bisthiol monomer, 2,2'-(ethylenedioxy)diethanethiol, and tetrathiol cross-linker, pentaerythritol tetrakis(3-mercaptopropionate). At optimal loading of lithium bis(trifluoromethane-sulfonyl-imide) (LiTFSI) salt, the ionic conductivities (σ) at 90 °C are about 1 × 10^-4 and 1 × 10^-5 S/cm at the lowest and highest cross-linking, respectively. Notably, in comparison to the equivalent nondynamic network, the dynamic network shows a positive deviation in σ above 90 °C, which suggests the enhancement of ion transport occurs from the difference in structural relaxation on account of the dissociation of disulfide bonds. Lap shear adhesion and conductivity tests on ITO-coated glass substrates reveal the dynamic network exhibits a higher adhesive shear strength of 0.2 MPa (vs 0.03 MPa for the nondynamic network) and higher σ after the application of external stimulus (UV light or heat). The adhesive strength and σ are stable over multiple debonding/rebonding cycles and, thus, demonstrating the utility of these structurally dynamic networks as solid polymer electrolyte adhesives.

Anion sensing properties of electrospun nanofibers incorporating a thiourea-based chromoionophore in methanol

To sense hydrophilic anions in protic solvents, we fabricated polymethylmethacrylate (PMMA) nanofibers incorporating 4-nitrophenyl azo thiourea polymer as a chromoionophore. When methanol solutions containing anions contacted the PMMA nanofiber, a bathochromic shift from 386 nm was observed in the absorption maximum of the chromoionophore. This spectral change is due to hydrogen bond formation between the urea moiety of the thiourea-based polymer and anions penetrating the nanofiber. This spectral change was not observed in PMMA film incorporating the same anion sensor, and the difference is attributed to the much larger specific surface area of the nanofiber compared to the film. As a result, many anions could react with the anion-sensing polymers in the nanofiber and induce a large spectral response.

[Clinical Significance of Palliative Esophageal Stent Placement for Esophageal Cancer]

BACKGROUND

Since the introduction of the guideline for the diagnosis and treatment of esophageal carcinoma in 2007, the indication for placing an esophageal stent has changed, especially with respect to the treatment of esophageal stricture after chemoradiotherapy(CRT). For CRT cases, irradiation after stent placement and stent placement after CRT are not recommended due to the risk of perforation.

METHODS

Thirty-eight patients who underwent esophageal stenting in our department between January 2007 and December 2018 and who were diagnosed with thoracic esophageal cancer were included in this study. We retrospectively examined the safety and treatment effect of esophageal stent placement.

RESULTS

Prior cancer therapy was observed in 16 cases(8 cases of chemotherapy and 8 cases of CRT). In the no prior therapy group, 13 cases were treated with BSC and 9 cases with chemotherapy. Esophageal stent placement after CRT was performed in 8 cases. Esophageal stent was placed 9(6-14)months after CRT. The stent patency period was 5(1-11)months, and the survival period after stent placement was 6(1-12)months. There was no difference in the frequency of complications and treatment outcomes of the CRT group compared with the non-CRT group.

CONCLUSION

Cases undergoing esophageal stent placement after CRT can expect therapeutic effects similar to those of other cases. However, complications such as perforation can be fatal; thus, careful consideration should be given to each individual case for esophageal stent placement after CRT.

[A Case of Brain, Lung, and Adrenal Metastasis from Colorectal Cancer Controlled by Loco-Regional Surgery]

A 64-year-old man presented with the chief complaint of weakness in the left half of his body. He fell down on the road while riding a bicycle and was transported to the emergency room. A contrast-enhanced brain MRI revealed a 28mm ringshaped mass in the right frontal lobe. A craniotomy was performed 14 days later. The histopathological diagnosis showed the tumor as a well-differentiated tubular adenocarcinoma. Postoperative examination revealed a rectal cancer and a left lung mass. A low-anterior resection was performed 1 month after the craniotomy, and a partial lung resection was performed 2 months after the rectal excision. Metachronous solitary metastasis of the left adrenal gland was noticed 10 months after the removal of the lung metastasis and we subsequently performed a left adrenalectomy. The patient is not undergoing any active treatment 13 months after the adrenalectomy, but has no signs of recurrence. The loco-regional surgery was enabled for local control of multi-relapsed lesions from rectal cancer.

SARC-F as a Screening Tool for Sarcopenia and Possible Sarcopenia Proposed by AWGS 2019 in Hospitalized Older Adults

OBJECT

The SARC-F questionnaire is a sarcopenia screening tool. However, the validity of the SARC-F score ≥4 (SARC-F≥4) for the evaluation of sarcopenia in the hospital setting has not been investigated. This study investigated the validity of SARC-F≥4 as a screening tool for sarcopenia among hospitalized older adults.

DESIGN

Cross-sectional retrospective study.

SETTING

A university hospital.

PARTICIPANTS

This study included older adult patients (age ≥65 years) who were hospitalized at, and subsequently discharged from, the hospital between April and September 2019 and underwent a nutritional assessment by the nutrition support team during their hospitalization.

MEASUREMENTS

SARC-F was recorded at the time of admission, and the criteria specified by the Asia Working Group for Sarcopenia in 2019 (AWGS 2019) were applied to diagnose sarcopenia and possible sarcopenia. Appendicular muscle mass was estimated through validated equations, and three different models were developed for sarcopenia diagnosis. The sensitivity, specificity, and positive/negative likelihood ratios were calculated to analyze the accuracy of the SARC-F≥4 for sarcopenia and possible sarcopenia. Receiver-operating characteristic analyses were conducted to calculate the area under the curve (AUC).

RESULTS

In total, 1,689 patients (mean age: 77.2±7.3 years; male: 54.4%) were analyzed, and 636 patients (37.7%) had SARC-F≥4. Patients with SARC-F≥4 had a statistically significant higher prevalence of AWGS 2019-defined sarcopenia than patients with SARC-F <4 in the models (65.4-78.9% vs 40.9-45.2%, p<0.001). The sensitivity, specificity, and positive/negative likelihood ratios of SARC-F≥4 for sarcopenia and possible sarcopenia were 49.1-51.3%, 73.9-81.2%, and 1.88-2.72/0.60-0.69 and 48.0%, 84.5%, and 3.11/0.62, respectively. The AUC for sarcopenia and possible sarcopenia were 0.644-0.695 and 0.708, respectively. The AUC of SARC-F for possible sarcopenia was equivalent to or larger than that for sarcopenia (DeLong test p=0.438, 0.088, and <0.001 vs the three models).

CONCLUSIONS

SARC-F≥4 is suitable as a screening tool for sarcopenia in hospitalized older adults. SARC-F assessment could facilitate the detection and exclusion of sarcopenia at hospitalization and may lead to early adoption of a therapeutic and preventive approach.

Absence of Magnetic Thermal Conductivity in the Quantum Spin Liquid Candidate EtMe_{3}Sb[Pd(dmit)_{2}]_{2}

We present the ultralow-temperature specific heat and thermal conductivity measurements on single crystals of triangular-lattice compound EtMe_{3}Sb[Pd(dmit)_{2}]_{2}, which has long been considered as a gapless quantum spin liquid candidate. In specific heat measurements, a finite linear term is observed, consistent with the previous work [S. Yamashita et al., Nat. Commun. 2, 275 (2011)NCAOBW2041-172310.1038/ncomms1274]. However, we do not observe a finite residual linear term in the thermal conductivity measurements, and the thermal conductivity does not change in a magnetic field of 6 T. These results are in sharp contrast to previous thermal conductivity measurements on EtMe_{3}Sb[Pd(dmit)_{2}]_{2} [M. Yamashita et al., Science 328, 1246 (2010)SCIEAS0036-807510.1126/science.1188200], in which a huge residual linear term was observed and attributed to highly mobile gapless excitations, likely the spinons of a quantum spin liquid. In this context, the true ground state of EtMe_{3}Sb[Pd(dmit)_{2}]_{2} has to be reconsidered.

Topological charge transport by mobile dielectric-ferroelectric domain walls

The concept of topology has been widely applied in condensed matter physics, leading to the identification of peculiar electronic states on three-dimensional (3D) surfaces or 2D lines separating topologically distinctive regions. In the systems explored so far, the topological boundaries are built-in walls; thus, their motional degrees of freedom, which potentially bring about new paradigms, have been experimentally inaccessible. Here, working with a quasi-1D organic material with a charge-transfer instability, we show that mobile neutral-ionic (dielectric-ferroelectric) domain boundaries with topological charges carry strongly 1D-confined and anomalously large electrical conduction with an energy gap much smaller than the one-particle excitation gap. This consequence is further supported by nuclear magnetic resonance detection of spin solitons, which are required for steady current of topological charges. The present observation of topological charge transport may open a new channel for broad charge transport-related phenomena such as thermoelectric effects.

Risk factors associated with increased drainage volumes of chest tubes after transthoracic esophagectomy for esophageal cancer

PURPOSE

Prolonged chest drain placement can extend the postoperative hospital stay after esophagectomy in esophageal cancer (EC) patients. This study aimed to identify whether or not the risk factors associated with this prolonged chest tube placement are clinically important.

METHODS

A total of 138 patients who underwent subtotal esophagectomy for thoracic EC were retrospectively analyzed. Using the 75th percentile of the total drainage volume of chest tubes as a cutoff value, the high-output (HO; n = 35) and low-output (LO; n = 103) groups were compared in terms of the clinicopathological parameters.

RESULTS

The median durations of right and left chest tube placement were 6 and 9 days, respectively, with a median total drainage volume of 2692 ml. When compared with the LO group, the HO group was significantly associated with male gender, a subcutaneous route for reconstruction, blood transfusion, higher morbidity, and prolonged chest drainage and postoperative hospital stays. A multivariable analysis further identified blood loss (p = 0.03) and the subcutaneous route for reconstruction (p = 0.04) as independent risk factors for increased chest tube drainage after esophagectomy.

CONCLUSION

Blood loss and the subcutaneous route of reconstruction are risk factors for increased drainage of chest tube after esophagectomy for EC.

Clozapine Normalizes a Glutamatergic Transmission Abnormality Induced by an Impaired NMDA Receptor in the Thalamocortical Pathway via the Activation of a Group III Metabotropic Glutamate Receptor

Pharmacological mechanisms of gold-standard antipsychotics against treatment-refractory schizophrenia, such as clozapine (CLZ), remain unclear. We aimed to explore the mechanisms of CLZ by investigating the effects of MK801 and CLZ on tripartite synaptic transmission in the thalamocortical glutamatergic pathway using multi-probe microdialysis and primary cultured astrocytes. l-glutamate release in the medial prefrontal cortex (mPFC) was unaffected by local MK801 administration into mPFC but was enhanced in the mediodorsal thalamic nucleus (MDTN) and reticular thalamic nucleus (RTN) via GABAergic disinhibition in the RTN–MDTN pathway. The local administration of therapeutically relevant concentrations of CLZ into mPFC and MDTN increased and did not affect mPFC l-glutamate release. The local administration of the therapeutically relevant concentration of CLZ into mPFC reduced MK801-induced mPFC l-glutamate release via presynaptic group III metabotropic glutamate receptor (III-mGluR) activation. However, toxic concentrations of CLZ activated l-glutamate release associated with hemichannels. This study demonstrated that RTN is a candidate generator region in which impaired N-methyl-d-aspartate (NMDA)/glutamate receptors likely produce thalamocortical hyperglutamatergic transmission. Additionally, we identified several mechanisms of CLZ relating to its superiority in treatment-resistant schizophrenia and its severe adverse effects: (1) the prevention of thalamocortical hyperglutamatergic transmission via activation of mPFC presynaptic III-mGluR and (2) activation of astroglial l-glutamate release associated with hemichannels. These actions may contribute to the unique clinical profile of CLZ.

Reversible Hydrogen Releasing and Fixing with Poly(Vinylfluorenol) through a Mild Ir-Catalyzed Dehydrogenation and Electrochemical Hydrogenation

The radical polymerization of 2-vinylfluorenol, an alcohol derivative of vinylfluorene, gives poly(vinylfluorenol), which quantitatively releases hydrogen gas (≈110 mL per gram polymer at standard temperature and pressure) by simply warming at 100 °C with an iridium catalyst. A high population of fluorenol units in the polymer accomplishes a large formula-weight-based theoretical hydrogen density (1.0 wt%). The dehydrogenated ketone derivative, poly(vinylfluorenone), exhibits reversible negative-charge storage with a high density of 260 mAh g^-1 . The electrolytically reduced poly(vinylfluorenone) is momentarily hydrogenated in the presence of an electrolyte with water as the hydrogen source to be converted to the original poly(vinylfluorenol). The formed poly(vinylfluorenol) almost quantitatively evolves hydrogen gas similar to the starting poly(vinylfluorenol). Both hydrogen and charge storage with the organic fluorenol/fluorenone polymer suggest a new type of energy-storage configuration.

Lower grip strength and dynamic body balance in women with distal radial fractures

In this case-control study, we concluded that women with distal radial fractures who were surgically treated showed lower grip strength and dynamic body balancing than those of controls. These results suggest that measurements of grip strength and dynamic body balance may be useful screening tools to assess future fracture risk.

INTRODUCTION

Patients with distal radial fractures (DRFs) are at risk of future fragility fractures. However, their physical characteristics and tendencies for falls remain unclear. We aimed to compare the physical characteristics of women with and without distal radial fractures.

METHODS

We included 128 women with a DRF as their first fragility fracture (fracture group) who underwent surgical treatment. Concurrently, 128 age- and sex-matched participants without a history of fragility fractures were selected as controls (control group). The participants underwent assessments of grip strength and the body balancing ability test. Measurements were taken twice in the fracture group, at 2 weeks and 6 months postoperatively, and once in the control group. The body balancing ability test included the Functional Reach Test, Timed Up and Go test (TUG), 2-Step test (2ST), and Timed Uni-pedal Stance test. The participants also completed questionnaires about their health.

RESULTS

There were no significant differences (p > 0.05) in patient characteristics between the groups. The fracture group showed lower grip strength across all age groups. In the DRF group, prolonged TUG time was observed at 2 weeks postoperatively in all age groups and at 6 months in participants aged 55-74 years; the 2ST score was significantly lower in participants aged between 65 and 74 years.

CONCLUSIONS

Women with DRF demonstrated lower grip strength and dynamic body balancing ability. Lower grip strength and dynamic body balancing ability were identified as significant risk factors in women with DRF, suggesting that these may be useful screening tools to assess fracture risk.

Fragmented Electronic Spins with Quantum Fluctuations in Organic Mott Insulators Near a Quantum Spin Liquid

Magnetic structures of organic Mott insulators X[Pd(dmit)_{2}]_{2} (X=Me_{4}P, Me_{4}Sb), of which electronic states are located near a quantum spin liquid (X=EtMe_{3}Sb), are demonstrated by ^{13}C nuclear magnetic resonance. Antiferromagnetic spectra and nuclear relaxations show two distinct magnetic moments within each Pd(dmit)_{2} molecule, which cannot be described by single band dimer-Mott model and requires intramolecular electronic correlation. This unconventional fragmentation of S=1/2 electron spin with strong quantum fluctuation is presumably caused by nearly degenerated intramolecular multiple orbitals, and shares a notion of quantum liquids where electronic excitations are fractionalized and S=1/2 spin is no longer an elementary particle.

A Case of Diffuse Esophageal Spasm Treated with Peroral Endoscopic Myotomy

The indications for peroral endoscopic myotomy (POEM) have been expanded to include diffuse esophageal spasm (DES). A 67-year-old Japanese man presented with a 4-year history of dysphagia. Endoscopy and upper gastrography revealed abnormal peristaltic movements involving interruption of normal peristalsis, and a diverticulum located at the 2 o'clock esophageal position. High-resolution manometry indicated DES. POEM with a long (15 cm) myotomy was performed for the abnormal contractions, which subsequently disappeared along with dysphagia improvement. Our results suggest that esophageal motility disorders accompanying a diverticulum may be eliminated by POEM without treating the diverticulum itself. We speculate that POEM ameliorates esophageal diverticulum by reducing internal esophageal pressure.

Correction to: Lower grip strength and dynamic body balance in women with distal radial fractures

The article Lower grip strength and dynamic body balance in women with distal radial fractures, written by. K. Fujita, H. Kaburagi, A. Nimura, T. Miyamoto, Y. Wakabayashi, Y. Seki, H. Aoyama, H. Shimura, R. Kato, A. Okawa was originally published electronically on the publisher's internet portal.