Oxygen diffusion of non-stoichiometric (La, Sr)MnO3 /CERIA NANO-composite SOFC cathode

Solid oxide fuel cell (SOFC) is one of the highly efficient energy generation system, and it requires higher power density per unit volume to expand SOFC stationary market as well as vehicle. Co-sintering of stacks or cells including electrodes, electrolyte and separators is most promising approach to improve the power density significantly. Generally, cathode materials have low heat resistant temperatures, and they were easily decomposed or degraded by sintering at a high temperature which is suitable for densification of SOFC electrolytes. Cathode material of (La1-xSrx)1-yMnO3 (LSM) shows relatively highly heat resistance and preferable low-reactivity with fluorite electrolytes during sintering at high temperatures. The addition of LSM also much increased degradation temperature. However, it shows lower cathodic properties than lanthanum strontium cobaltite and lanthanum strontium cobalt ferrite because of poor oxygen ionic conduction. We thus investigate LSM/ceria nanocomposite cathode materials to improve oxygen ionic conduction. The nanocomposite precursor powder containing LSM and lanthanum doped ceria (LDC) was synthesized by glycine method. Two stoichiometric compositions, which are stoichiometric composition (y=0) and non-stoichiometric (y=0.05), were prepared as LSM, and LDCs that were dissolved with lanthanum at various ratios were used to investigate inter-diffusion of lanthanum between LSM and LDC. The composite ratio of LSM and CeO2 was fixed at 9: 1 (molar ratio). Figure 1 shows SEM image of LSM/LDC nanocomposite sintered at 1200oC for 5 h in air. Sintering at 1200oC for 5h resulted in dense composite, and fine LDC particles were homogeneously dispersed with LSM. Lanthanum ratios of LDC and LSM in the composite were identified using XRD peak shift of LDC and magnetic properties of LSM, respectively. Electrical conductivity and oxygen diffusion coefficient were estimated with these dense composites. Oxygen diffusion coefficient were obtained by electrical conductivity relaxation method. Please click Additional Files below to see the full abstract

Influence of substituent modifications on the binding of 2-amino-1,8-naphthyridines to cytosine opposite an AP site in DNA duplexes: thermodynamic characterization

Here, we report on a significant effect of substitutions on the binding affinity of a series of 2-amino-1,8-naphthyridines, i.e., 2-amino-1,8-naphthyridine (AND), 2-amino-7-methyl-1,8-naphthyridine (AMND), 2-amino-5,7-dimethyl-1,8-naphthyridine (ADMND) and 2-amino-5,6,7-trimethyl-1,8-naphthyridine (ATMND), all of which can bind to cytosine opposite an AP site in DNA duplexes. Fluorescence titration experiments show that the binding affinity for cytosine is effectively enhanced by the introduction of methyl groups to the naphthyridine ring, and the 1:1 binding constant (106 M−1) follows in the order of AND (0.30) < AMND (2.7) < ADMND (6.1) < ATMND (19) in solutions containing 110 mM Na+ (pH 7.0, at 20°C). The thermodynamic parameters obtained by isothermal titration calorimetry experiments indicate that the introduction of methyl groups effectively reduces the loss of binding entropy, which is indeed responsible for the increase in the binding affinity. The heat capacity change (ΔCp), as determined from temperature dependence of the binding enthalpy, is found to be significantly different between AND (−161 cal/mol K) and ATMND (−217 cal/mol K). The hydrophobic contribution appears to be a key force to explain the observed effect of substitutions on the binding affinity when the observed binding free energy (ΔGobs) is dissected into its component terms

Urine Lactoferrin as a Potential Biomarker Reflecting the Degree of Malignancy in Urothelial Carcinoma of the Bladder

Urothelial carcinoma of the bladder (UCB) is potentially life-threatening; therefore, we aimed to discover a novel urine biomarker for diagnosis and prognostication of UCB. This is a retrospective case-control study. Exploration of a new biomarker using urine from 20 UCB patients in the present study revealed that urinary level of lactoferrin (LF), a multifunctional glycoprotein released from neutrophils, was higher in 11 of 15 with invasive/high-grade UCB than 5 with non-invasive one, and 2 healthy adults. We therefore focused on LF and assessed the value of urine LF normalized by urine creatinine concentration (LF/Cr) using an enzyme-linked immunosorbent assay. Diagnostic performance of urine LF/Cr was examined using urine from 92 patients with primary (newly diagnosed) untreated UCB and 166 controls without UCB, including 62 patients with pyuria, and 104 subjects without pyuria consisting of 84 patients and 20 healthy adults. However, the diagnostic accuracies were accompanied by the risk of bias. In 92 primary UCB patients, both pyuria and tumor-infiltrating neutrophils (TINs) were independent predictors for urine LF/Cr. In contrast, TINs or urine LF/Cr were independent predictors for invasive histology, whereas pyuria was not. In terms of prognostication, urine LF/Cr and nodal metastasis were independent predictors of disease-specific survival in 22 patients with muscle-invasive bladder cancer, characterized by a high mortality rate, in the Cox proportional hazards model. In conclusion, urine LF/Cr linked to TINs was a predictor of both invasive histology and prognosis in UCB. Urine LF/Cr is a potential biomarker reflecting the degree of malignancy in UCB

Increased level of serum leucine-rich-alpha-2-glycoprotein 1 in patients with clear cell renal cell carcinoma

Abstract Background Currently, no useful serum markers exist for clear cell renal cell carcinoma (ccRCC), making early detection challenging as diagnosis relies solely on imaging tests. Radiation exposure is also a concern due to multiple required CT examinations during treatment. Renal cell carcinoma (RCC) histological types include ccRCC and non-clear cell RCC (non-ccRCC); however, treatment response to medications varies which necessitates accurate differentiation between the two. Therefore, we aimed to identify a novel serum marker of RCC. Increased LRG1 expression in the serum has been demonstrated in multiple cancer types. However, the expression of LRG1 expression in the serum and cancer tissues of patients with RCC has not been reported. Since ccRCC is a hypervascular tumor and LRG1 is capable of accelerating angiogenesis, we hypothesized that the LRG1 levels may be related to ccRCC. Therefore, we examined LRG1 expression in sera from patients with RCC. Methods Using an enzyme-linked immunosorbent assay, serum levels of leucine-rich-alpha-2-glycoprotein 1 (LRG1) were measured in 64 patients with ccRCC and 22 patients non-ccRCC who underwent radical or partial nephrectomy, as well as in 63 patients without cancer. Results Median values of serum LRG1 and their inter-quartile ranges were 63.2 (42.8–94.2) µg/mL in ccRCC, 23.4 (17.7–29.6) µg/mL in non-ccRCC, and 36.0 (23.7–56.7) µg/mL in patients without cancer, respectively (ccRCC vs. non-ccRCC or patients without cancer: P < 0.001). C-reactive protein (CRP) levels (P = 0.002), anemia (P = 0.037), hypercalcemia (P = 0.023), and grade (P = 0.031) were independent predictors of serum LRG1 levels in ccRCC. To assess diagnostic performance, the area under the receiver operating characteristic curve of serum LRG1 was utilized to differentiate ccRCC from non-cancer and non-ccRCC, with values of 0.73 (95% CI, 0.64–0.82) and 0.91 (95% CI, 0.82–0.96), respectively. Conclusions LRG1 served as a serum marker associated with inflammation, indicated by CRP, anemia, hypercalcemia, and malignant potential in ccRCC. Clinically, serum LRG1 levels may assist in differentiating ccRCC from non-ccRCC with excellent diagnostic accuracy

Stage-specific embryonic antigen-4 is a histological marker reflecting the malignant behavior of prostate cancer

Stage-specific embryonic antigen-4 (SSEA-4), a specific marker for pluripotent stem cells, plays an important role in the malignant behavior of several cancers. Here, SSEA-4 expression was evaluated by immunohistochemistry using monoclonal antibody RM1 specific to SSEA-4 in 181 and 117 prostate cancer (PC) specimens obtained by biopsy and radical prostatectomy (RP), respectively. The relationships between SSEA-4 expression in cancer cells or the presence of SSEA-4-positive tumor-infiltrating immune cells (TICs) and clinicopathological parameters were analyzed. SSEA-4 expression in cancer cells was significantly associated with Gleason score, local progression, and lymph node and distant metastasis. In RP specimens, high SSEA-4 expression in cancer cells and the presence of SSEA-4-positive TICs were significant predictors of pT3, i.e., invasion and worse biochemical recurrence (BCR) after RP, respectively, in univariate analysis. In contrast, combination of high SSEA-4 expression in cancer cells and the presence of SSEA-4-positive TICs was an independent predictor for pT3 and BCR in multivariate analysis. Biologically this combination was also independently associated with suppression of apoptosis. Thus, the co-expression of SSEA-4 in cancer cells and TICs may have crucial roles in the malignant aggressiveness and prognosis of PC. Invasive potential and suppression of apoptosis may be linked to SSEA-4 expression