Phase equilibrium relations of tetra-n-butylphosphonium propionate and butyrate semiclathrate hydrates

This paper reports phase equilibrium (temperature–composition) relations of semiclathrate hydrates formed from tetra-n-butylphosphonium propionate (TBP-Pro) and butyrate (TBP-But) + water systems. Their maximum solid–liquid phase equilibrium temperatures at atmospheric pressure were located at (288.75 ± 0.06) K and the mole fraction x1 = 0.035 ± 0.001 and (287.01 ± 0.06) K and x1 = 0.028 ± 0.001, respectively. They showed equilibrium temperatures higher than those of tetra-n-butylphosphonium formate, acetate, and lactate semiclathrate hydrates. The dissociation enthalpies of TBP-Pro and TBP-But semiclathrate hydrates were (190 ± 5) J·g−1 and (204 ± 5) J·g−1, respectively. The temperature difference between formation and dissociation, that is, the maximum allowable degree of supercooling, was (17.7 ± 1.5) K for TBP-Pro semiclathrate hydrate and (15.4 ± 1.4) K for TBP-But one

Phase equilibrium relations for tetra-n-butylphosphonium acetate semiclathrate hydrate systems in the presence of methane, carbon dioxide, nitrogen, or ethane

Thermodynamic stabilities of tetra-n-butylphosphonium acetate (TBP-Ace) semiclathrate hydrates in the presence of methane (CH 4 ), carbon dioxide (CO 2 ), nitrogen (N 2 ), or ethane (C 2 H 6 ) were measured in a pressure range up to approximately 5 MPa. The dissociation temperature of TBP-Ace + CH 4 , TBP-Ace + CO 2 , and TBP-Ace + N 2 semiclathrate hydrates increased drastically with an increase in pressure, which means that CH 4 , CO 2 , and N 2 molecules occupy the vacant cages of the TBP-Ace semiclathrate hydrate. On the other hand, the C 2 H 6 molecules hardly occupied the cages, resulting in small pressure dependence of the dissociation temperature. Raman spectra and powder X-ray diffraction patterns of TBP-Ace + CO 2 semiclathrate hydrate reveal that the phase transition occurs at 1.04 ± 0.04 MPa and 285.88 ± 0.05 K. One of the possible reasons why the phase transition occurs is that the carbonate and/or hydrogen carbonate anions derived from the CO 2 molecules are replaced with some of acetate anions in the TBP-Ace + CO 2 semiclathrate hydrate

Phase equilibrium temperature and dissociation enthalpy in the tri-n-butylalkylphosphonium bromide semiclathrate hydrate systems

Semiclathrate hydrate (SCH) is one of the phase change materials suitable for cold storage. The thermodynamic properties of SCHs, such as an equilibrium temperature and a dissociation enthalpy, depend on the size and shape of guest substances. In this study, to reveal the effect of cation size and shape on the thermodynamic properties, tri-n-butylalkylphosphonium bromide (P444R-Br) SCHs, where the alkyl group was n-propyl (R = 3), n-butyl (R = 4), n-pentyl (R = 5), i-butyl (R = i-4), i-pentyl (R = i-5), or allyl (R = Al)), were investigated. The branched alkyl groups (R = i-4 or i-5) raised the equilibrium temperature, whereas the shorter alkyl groups (R = 3 or Al) lowered one. Except for P4445-Br and P444(Al)-Br SCHs, the other P444R-Br SCHs had the same orthorhombic structure. Among the orthorhombic systems in the present study, the semiclathrate hydrate with a higher equilibrium temperature had a larger dissociation enthalpy

Phase Equilibrium Relations of Semiclathrate Hydrates Based on Tetra- n-butylphosphonium Formate, Acetate, and Lactate

Phase equilibrium (temperature-composition) relations of tetra-n-butylphosphonium formate (TBP-For), acetate (TBP-Ace), and lactate (TBP-Lac) semiclathrate hydrate systems have been measured. The highest equilibrium temperatures of TBP-For, TBP-Ace, and TBP-Lac semiclathrate hydrates were 280.9, 284.6, and 283.8 K at the atmospheric pressure, respectively, where the composition of tetra-n-butylphosphonium carboxylate was approximately 0.035 ± 0.001 (mole fraction) in every system. The dissociation enthalpies of tetra-n-butylphosphonium carboxylate semiclathrate hydrates were measured by differential scanning calorimetry. The dissociation enthalpies of TBP-For, TBP-Ace, and TBP-Lac semiclathrate hydrates were (187 ± 3), (193 ± 3), and (177 ± 3) J·g-1, respectively.Jin Shimada, Masami Shimada, Takeshi Sugahara, et al. Phase Equilibrium Relations of Semiclathrate Hydrates Based on Tetra-n-butylphosphonium Formate, Acetate, and Lactate. Journal of Chemical & Engineering Data, 63 (9), 3615-3620, September 13, © 2018 American Chemical Society. https://doi.org/10.1021/acs.jced.8b0048

Thermodynamic Properties of Tetra-n-butylphosphonium Dicarboxylate Semiclathrate Hydrates

Semiclathrate hydrate (SCH) is one of the phase change materials suitable for cold energy storage. Thermodynamic properties of SCHs, such as an equilibrium temperature and the dissociation enthalpy, depend on the size and shape of the guest substances. In the present study, to reveal the effects of steric conformations of the guest anions on the thermodynamic properties of SCHs, tetra-n-butylphosphonium dicarboxylate (TBP-DC) SCHs, where the anion was oxalate (TBP-Oxa), malonate (TBP-Mal), succinate (TBP-Suc), glutarate (TBP-Glu), maleate (TBP-Male), or fumarate (TBP-Fum), were investigated. TBP-Oxa, -Mal, -Suc, and -Fum SCHs had similar equilibrium temperatures, whereas the equilibrium temperatures of TBP-Glu and -Male SCHs were higher. This suggests that the size and conformation of glutarate and maleate anions are appropriate for the cage structures of SCHs. Moreover, we compared the equilibrium temperatures of TBP-Suc, -Male, and -Fum SCHs because TBP-Suc, -Male, and -Fum have similar anion structures. The equilibrium temperature of TBP-Suc SCH was similar to that of TBP-Fum SCH, whereas TBP-Male SCH showed a higher equilibrium temperature. This result implies that the succinate anion is accommodated in the trans conformation, similar to the fumarate anion, in the hydrate cages.Jin Shimada, Moe Yamada, Atsushi Tani et al. Thermodynamic Properties of Tetra-n-butylphosphonium Dicarboxylate Semiclathrate Hydrates. Journal of Chemical & Engineering Data, 67 (1), 67-73, January 13, © 2022 American Chemical Society. https://doi.org/10.1021/acs.jced.1c0074

Expression of TLR4/MyD88 in CRC

BACKGROUND: The Toll-like receptor (TLR) 4 signalling pathway has been shown to have oncogenic effects in vitro and in vivo. To demonstrate the role of TLR4 signalling in colon tumourigenesis, we examined the expression of TLR4 and myeloid differentiation factor 88 (MyD88) in colorectal cancer (CRC). METHODS: The expression of TLR4 and MyD88 in 108 CRC samples, 15 adenomas, and 15 normal mucosae was evaluated by immunohistochemistry, and the correlations between their immunoscores and clinicopathological variables, including disease-free survival (DFS) and overall survival (OS), were analysed. RESULTS: Compared with normal mucosae and adenomas, 20% cancers displayed high expression of TLR4, and 23% cancers showed high expression of MyD88. The high expression of TLR4 and MyD88 was significantly correlated with liver metastasis (P=0.0001, P=0.0054). In univariate analysis, the high expression of TLR4 was significantly associated with shorter OS (hazard ratio (HR): 2.17; 95% confidence interval (95% CI): 1.15–4.07; P=0.015). The high expression of MyD88 expression was significantly associated with poor DFS and OS (HR: 2.33; 95% CI: 1.31–4.13; P=0.0038 and HR: 3.03; 95% CI: 1.67–5.48; P=0.0002). The high combined expression of TLR4 and MyD88 was also significantly associated with poor DFS and OS (HR: 2.25; 95% CI: 1.27–3.99; P=0.0053 and HR: 2.97; 95% CI: 1.64–5.38; P=0.0003). Multivariate analysis showed that high expressions of TLR4 (OS: adjusted HR: 1.88; 95% CI: 0.99–3.55; P=0.0298) and MyD88 (DFS: adjusted HR: 1.93; 95% CI: 1.01–3.67; P=0.0441; OS: adjusted HR: 2.25; 95% CI: 1.17–4.33; P=0.0112) were independent prognostic factors of OS. Furthermore, high co-expression of TLR4/MyD88 was strongly associated with both poor DFS and OS. CONCLUSION: Our findings suggest that high expression of TLR4 and MyD88 is associated with liver metastasis and is an independent predictor of poor prognosis in patients with CRC

The Electrocatalytic Oxidation of Ethylene and Methane, and Reduction of Oxygen on Gas-Diffusion Electrodes Made of Amorphous Nickel-Valve Metal-Platinum Group Metal Alloys

Exploratory work has been done on the performance of electrocatalytic reduction of oxygen and anodic oxidation of ethylene and methane on the gas-diffusion electrodes prepared from amorphous alloys containing one atomic percent platinum group elements. Gas-diffusion electrodes were made by coating the mixture of catalysts prepared by immersion in 46% HF from melt-spun ribbon shaped amorphous alloys, carbon black, polytetrafluoroethylene and sugar, and subsequent baking in nitrogen gas. The electrode made of catalyst prepared from amorphous nickel-niobium alloy containing platinum and ruthenium was the most active for electrocatalytic reduction of oxygen. For electro-oxidation of ethylene and methane, amorphous nickel-value metal alloy containing only platinum possesses higher activity in comparison to the electrode made of platinum black powder

Pretransplant assessment of human liver grafts by plasma lecithin: cholesterol acyltransferase (LCAT) activity in multiple organ donors.

In spite of the improved outcome of orthotopic liver transplantation (OLTx), primary graft nonfunction remains one of the life-threatening problems following OLTx. The purpose of this study was to evaluate plasma lecithin: cholesterol acyltransferase (LCAT) activity in multiple organ donors as a predictor of liver allograft viability prior to OLTx. Thirty-nine donors were studied during a 5-month period between April and August 1988. Allograft hepatectomy was performed using a rapid technique or its minor modification with hilar dissections, and the allografts were stored cold (4 degrees C) in University of Wisconsin (UW) solution. Early post-transplant allograft function was classified as good, fair, or poor, according to the highest SGOT, SGPT, and prothrombin time within 5 days following OLTx. Procurement records were reviewed to identify donor data, which included conventional liver function tests, duration of hospital stay, history of cardiac arrest, and graft ischemic time. Blood samples from the donors were drawn immediately prior to aortic crossclamp, and from these plasma LCAT activity was determined. Plasma LCAT activity of all donors was significantly lower than that of healthy controls (12.4 +/- 8.0 vs 39.2 +/- 13.3 micrograms/ml per hour, P less than 0.01). LCAT activity (16.4 +/- 8.3 micrograms/ml per hour) in donors of grafts with good function was significantly higher than that in those with fair (8.6 +/- 4.5 micrograms/ml per hour, P less than 0.01) or poor (7.3 +/- 2.4 micrograms/ml per hour, P less than 0.01) function.(ABSTRACT TRUNCATED AT 250 WORDS

卵巣明細胞腺癌における転写因子HNF-1βはDNA損傷チェックポイント機構の一つであるCHK1タンパクを制御し、抗癌剤耐性を獲得する

Objective Appropriate cell cycle checkpoints are essential for the maintenance of normal cells and chemosensitivity of cancer cells. Clear cell adenocarcinoma (CCA) of the ovary is highly resistant to chemotherapy. Hepatocyte nuclear factor-1β (HNF-1β) is known to be overexpressed in CCA, but its role and clinical significance is unclear. We investigated the role of HNF-1β in regulation of the cell cycle in CCA. Methods To clarify the effects of HNF-1β on cell cycle checkpoints, we compared the cell cycle distribution and the expression of key proteins involved in CCA cells in which HNF-1β had been stably knocked down and in vector-control cell lines after treatment with bleomycin. HNF-1β (+) cells were arrested in G2 phase because of DNA damage. Results HNF-1β (−) cells died because of a checkpoint mechanism. G2 arrest of HNF-1β (+) cells resulted from sustained CHK1 activation, a protein that plays a major role in the checkpoint mechanism. HNF-1β (+) cells were treated with a CHK1 inhibitor after bleomycin treatment. Flow cytometric analysis of the cell cycle demonstrated that DNA damage–induced G2-arrested cells were released from the checkpoint and killed by a CHK1 inhibitor. Conclusions The chemoresistance of CCA may be due to aberrant retention of the G2 checkpoint through overexpression of HNF-1β. This is the first study demonstrating cell cycle regulation and chemosensitization by a CHK1 inhibitor in CCA.博士（医学）・乙第1345号・平成26年12月3日© 2014 by the International Gynecologic Cancer Society and the European Society of Gynaecological Oncology

Enhanced production of nitric oxide, reactive oxygen species, and pro-inflammatory cytokines in very long chain saturated fatty acid-accumulated macrophages

<p>Abstract</p> <p>Background</p> <p>Deterioration of peroxisomal β-oxidation activity causes an accumulation of very long chain saturated fatty acids (VLCSFA) in various organs. We have recently reported that the levels of VLCSFA in the plasma and/or membranes of blood cells were significantly higher in patients with metabolic syndrome and in patients with coronary artery disease than the controls. The aim of the present study is to investigate the effect of VLCSFA accumulation on inflammatory and oxidative responses in VLCSFA-accumulated macrophages derived from X-linked adrenoleukodystrophy (X-ALD) protein (ALDP)-deficient mice.</p> <p>Results</p> <p>Elevated levels of VLCSFA were confirmed in macrophages from ALDP-deficient mice. The levels of nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) and interferon-γ (IFN-γ), intracellular reactive oxygen species (ROS), and pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interluekin-6 (IL-6), and interleukin-12p70 (IL-12p70), were significantly higher in macrophages from ALDP-deficient mice than in those from wild-type mice. The inducible NO synthase (iNOS) mRNA expression also showed an increase in macrophages from ALDP-deficient mice.</p> <p>Conclusion</p> <p>These results suggested that VLCSFA accumulation in macrophages may contribute to the pathogenesis of inflammatory diseases through the enhancement of inflammatory and oxidative responses.</p