Synthesis of a Novel Family of Polysilsesquioxanes Having Oligothiophenes with Well-Defined Structures

Our recent results on the synthesis and properties of a novel family of polysilsesquioxanes having oligothiophenes were reviewed. The polymers anchored on SiO2 or ITO substrates showed excellent mechanical hardness due to the formation of a three-dimensional siloxane network structure and chemical linkage between polymer and the surface of metal-oxide substrates. Optical, electrochemical, and electrical properties of polymers were also investigated

Layer-selective spin amplification in size-modulated quantum nanocolumn

The optical spin properties of size-modulated quantum nanocolumns (QNCs), which are composed of 9 layers of vertically coupled InGaAs quantum dots (QDs), have been studied by circularly polarized time-resolved photoluminescence spectroscopy of QD excited states with barrier excitation. High spin polarization at the emissive state is one of the essential elements in the development of spin-functional optical devices. Coupling of QD excited states can enhance the spin polarization if only minority spins are effectively removed from the emissive excited states. In this study, size-modulated QNCs with the increasing size toward the upper layer were grown, and we revealed that the combination of QD size modulation and electron wavefunction coupling in the stacking direction can greatly enhance spin polarization during light emission from the smaller-sized QD layers. We observed a temporal spin amplification of more than 80% at coupled excited states. This enhancement is derived from the size-modulation-induced selective transfer of minority spins to the larger-sized QD layers, which have abundant excited states where electron spins are transferred. In addition, we found that QNCs can retain high spin polarization even at high excitation spin density. Our findings of spin amplification during light emission will provide QNC systems suitable for spin-functional optical devices. Published under license by AIP Publishing

Magnetic Resonance Imaging Study on the Physical Stability of Menthol and Diphenhydramine Cream for the Treatment of Chronic Kidney Disease-Associated Pruritus

A cream that contains menthol and diphenhydramine is widely prepared in hospital pharmacies and prescribed to patients for the treatment of pruritus associated with chronic kidney disease. However, there is a serious concern regarding its physical stability; therefore, we investigated this issue using magnetic resonance imaging (MRI). For a sample preparation, a menthol-containing ethanol solution was mixed with a commercial diphenhydramine cream. After storage for 7 d at 40°C, substantial phase separation into two distinct layers (upper and lower layers) was observed in the sample. This study further examined the components of the phase-separated layers using magnetic resonance (MR) spectroscopy and chemical shift selective images, and it was verified that the upper layer consisted of packed oil droplet layers, whereas the lower was an aqueous phase. Subsequently, the time-dependent phase separation of the sample at different temperatures was investigated. From the MR images, including a T2 relaxation time map and apparent diffusion coefficient maps, it was obvious that the phase separation developed further with increasing temperature; the most substantial phase separation was observed from the sample stored at 40°C, while no phase separation was detected at 25°C. In the final phase of this study, we conducted a formulation study and succeeded in improving the cream’s physical stability by adding a hydrophilic surfactant to the preparation

Magnetic Resonance Imaging Study on the Physical Stability of Menthol and Diphenhydramine Cream for the Treatment of Chronic Kidney Disease-Associated Pruritus

A cream that contains menthol and diphenhydramine is widely prepared in hospital pharmacies and prescribed to patients for the treatment of pruritus associated with chronic kidney disease. However, there is a serious concern regarding its physical stability; therefore, we investigated this issue using magnetic resonance imaging (MRI). For a sample preparation, a menthol-containing ethanol solution was mixed with a commercial diphenhydramine cream. After storage for 7 d at 40°C, substantial phase separation into two distinct layers (upper and lower layers) was observed in the sample. This study further examined the components of the phase-separated layers using magnetic resonance (MR) spectroscopy and chemical shift selective images, and it was verified that the upper layer consisted of packed oil droplet layers, whereas the lower was an aqueous phase. Subsequently, the time-dependent phase separation of the sample at different temperatures was investigated. From the MR images, including a T2 relaxation time map and apparent diffusion coefficient maps, it was obvious that the phase separation developed further with increasing temperature; the most substantial phase separation was observed from the sample stored at 40°C, while no phase separation was detected at 25°C. In the final phase of this study, we conducted a formulation study and succeeded in improving the cream’s physical stability by adding a hydrophilic surfactant to the preparation

Development of anchored oligothiophenes on substrates for the application to the tunable transparent conductive films

Bis(triethoxysilyl)-substituted oligothiophene with a moderate π-conjugation length was newly synthesized and polymerized to give a polysilsesquioxane network having oligothiophene units dispersed homogeneously without phase separation. The polymer was fixed on glass or ITO substrate by spin-coating and annealing. The resulting film exhibited a high mechanical strength due to the covalent bonding with the substrates, and was electrochemically stable even after 300 redox cycles in electrolyte solution. Chemical oxidation of the polymer films yielded electrically conductive and almost transparent films

PCP4/PEP19 and HER2 Are Novel Prognostic Markers in Mucoepidermoid Carcinoma of the Salivary Gland

Mucoepidermoid carcinoma (MEC) is one of the most common malignant salivary gland carcinomas, but no effective treatment strategy has been established other than surgical resection. Purkinje cell protein (PCP) 4/peptide (PEP) 19 is a calmodulin-binding antiapoptotic peptide that is expressed and inhibits apoptosis in human breast cancer cells. Human epidermal growth factor receptor 2 (HER2) is an epidermal growth factor that has been implicated in the pathogenesis of many carcinomas, particularly breast and gastric carcinomas. In the present study, we performed immunohistochemical analyses of samples from 73 patients who underwent surgical resection for MEC of the salivary gland using antibodies against PCP4/PEP19 and HER2. PCP4/PEP19 expression was related to better prognosis, while HER2 expression was associated with worse prognosis. Patients that were PCP4/PEP19-positive and HER2-negative showed similar outcomes to PCP4/PEP19 and HER2 alone. Therefore, PCP4/PEP19 and HER2 are predicted to play important roles in the pathogenesis and progression of MEC

Impact of Preoperative Low Prognostic Nutritional Index and High Intramuscular Adipose Tissue Content on Outcomes of Patients with Oral Squamous Cell Carcinoma

The impact of preoperative malnutrition and sarcopenia on survival in oral squamous cell carcinoma (OSCC) patients remains controversial. We investigated the effects of the preoperative nutritional status and abnormalities in body composition on the mortality of OSCC patients. A retrospective study involving 103 patients with OSCC was conducted. Disease-specific survival (DSS) according to the preoperative psoas muscle mass index (PMI) and intramuscular adipose tissue content (IMAC) was evaluated. Univariate and multivariate analyses were performed to determine the predictive performance of the covariates with respect to DSS. The DSS rate in patients with high IMAC and low PMI was significantly lower than that in controls. Multivariate analysis revealed that a low preoperative Prognostic Nutritional Index (PNI) and high IMAC were independent risk factors. We demonstrated that preoperative malnutrition and abnormal body composition, such as preoperative skeletal muscle quality, are associated with DSS in OSCC patients. Our study suggests that the evaluation of preoperative malnutrition and skeletal muscle quality would be useful for predicting mortality in patients with OSCC