Induction of thioredoxin, a redox-active protein, by ovarian steroid hormones during growth and differentiation of endometrial stromal cells in vitro

Human thioredoxin (hTrx) is a cellular redox-active protein that catalyzes dithiol/disulfide exchange reactions, thus controlling multiple biological functions, including cell growth-promoting activity. Here we show that the expression of hTrx protein and messenger RNA was up-regulated by incubation with 17beta-estradiol (E2) in primary culture of stromal cells isolated from human endometrium. Maximal enhancement of hTrx protein and messenger RNA was observed after 6-12 h of incubation with 10-100 nM E2, and the enhancing effect was suppressed by tamoxifen, an estrogen antagonist. Release of hTrx into the culture medium was markedly augmented after 5-day exposure of E2 plus progesterone (P) accompanied by in vitro differentiation of endometrial stromal cells (decidualization). Immunocytochemical studies showed that hTrx was localized in the nucleus, nucleolus, and cytosol in the stromal cells. Strongly enhanced immunoreactivity for hTrx was observed in the E2-treated cells, whereas there was no apparent difference in the pattern of subcellular localization among the untreated and E2- and/or P-treated cells. Although 1-50 microg/ml recombinant hTrx alone did not promote endometrial stromal cell growth, epidermal growth factor-dependent mitogenesis was additively enhanced by hTrx. Our results indicate that hTrx modulates endometrial cell growth, acting as a comitogenic factor for epidermal growth factor, which is known to be a mediator of estrogen action. It is also suggested that hTrx is deeply involved in the hormonal control of the endometrium by E2 and P, playing a regulatory role in endometrial cell growth and differentiation.     

XPS studies on the oxygen species of LaMn1−xCuxO3+λ

The electronic states of LaMn_1−xCu_xO_3+λ (x=0–0.4) have been studied with X-ray photoelectron spectroscopy (XPS). The valence states of substituted copper ions were Cu²⁺ and the manganese ions were a highly mixed state of Mn³⁺ and Mn⁴⁺. The nonstoichiometry and electronic state of lattice oxygen have been studied. The samples at x=0 and 0.1 had an excess of lattice oxygen but those at x=0.2–0.4 had lattice oxygen deficiency. A modified Auger parameter (Δ′) was used to evaluate the electronic states of oxygen ions. The Δ′ of lattice oxygen increased with increasing substitute quantity. This increase of Δ′ reflected the decrease of ionic bond character of lattice oxygen. The adsorbed oxygen species on LaMn_1−xCu_xO_3+λ was assigned mainly as O⁻ from the peak positions of spectra for the O 1s and O KLL levels, and the Δ′ of this O⁻ decreased with x. This decrease, i.e., the increase of ionic bond character of adsorbed oxygen was correlated well with the value of nonstoichiometry of lattice oxygen.

The rate of CO oxidation at 448 K was increased by the substitution till x=0.4. We consider that this enhancement of reactivity comes from the change of electronic state of adsorbed oxygen, O⁻ itself, i.e., a weak interaction between O⁻ and low coordinated metal site brings about a high reactivity.     

Complexation of cobalt ion with copolypeptide containing tryptophan treated with nitric acid

Summary Tryptophan within copoly(N-hydroxyethyl L-glutamine-co-L-tryptophan) treated with nitric acid (EGT-N) dissociates negatively above pH 10.5 by the electron-attractive effect of nitro groups introduced into the indole ring. The interaction between EGT-N and various metal ions was investigated using UV/VIS, ESCA, and ICP measurement. EGT-N was found to selectively form a complex with cobalt ions above pH 10.5. The formation of the cobalt ion complex of EGT-N was confirmed to be caused by the cooperative coordination of the tryptophan-introduced nitro groups and the OH groups of hydroxyethyl L-glutamine. Received: 12 January 1998/Revised version: 6 March 1998/Accepted: 9 March 1998     

Glycated Albumin versus Glycated Hemoglobin as a Glycemic Indicator in Diabetic Patients on Peritoneal Dialysis

Compared with glycated hemoglobin (HbA1c), glycated albumin (GA) is superior in estimating glycemic control in diabetic patients on hemodialysis (HD). However, the better index for assessment of glycemic control in diabetic patients on peritoneal dialysis (PD) and the impact of protein loss on GA are unknown. Twenty diabetic patients on HD were matched by age, sex, and baseline postprandial plasma glucose (PG) levels to 20 PD patients. PG, HbA1c, GA, and serum albumin levels were measured for six months. Protein loss in PD patients was estimated by measuring the protein concentration in the peritoneal dialysate and by 24 h urine collection. Although PG and HbA1c did not differ significantly between the groups, the PD group had significantly lower GA (17.8% versus 20.8%, p < 0.001) and GA/HbA1c ratio (2.95% versus 3.45%, p < 0.0001) than the HD group. Although the PG level correlated significantly with the GA levels in both groups, it was not correlated with the HbA1c levels in both groups. HbA1c level was negatively associated with erythropoiesis-stimulating agent (ESA) dose in both groups, whereas GA was not significantly associated with serum albumin, hemoglobin concentration, ESA dose, and protein loss. Multiple regression analysis identified GA as the only independent factor associated with PG in PD patients. Our results suggested that GA was not significantly associated with protein loss, hemoglobin, serum albumin, and ESA dose. Although GA might underestimate glycemic status, it provided a significantly better measure for estimating glycemic control than HbA1c, even in PD patients.     

Characteristics of heat transfer and temperature rise of hydrogen during rapid hydrogen filling at high pressure

An experiment has been done to measure the rise in temperature of a gas during filling a tank at high pressure. The experimental condition is that filling gases are nitrogen and hydrogen at a pressure of 5 to 35 MPa and at a filling mass of G=45 to 324 g/min for hydrogen. The temperatures are measured either horizontally or vertically at five positions in the tank. It is found that heat loss transferred from compressed gas to the tank wall has a significant effect on the rise in the filled gas temperature. The heat transfer coefficient is estimated after the end of filling and is about α_h=270 W/(m²K) for the hydrogen at 35 MPa. A theoretical procedure is proposed to calculate the temperature increase of the gas on a basis of assumption that the gas temperature in the tank is uniform at any time, and the heat transfer coefficient is given. The calculation shows that the temperature is in reasonable agreement with the measured temperatures by assuming α_h=500 W/(m²K) during the filling of hydrogen at 35 MPa, although the estimated heat loss after the end of filling becomes larger than the actual one. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(1): 13–27, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20140     

Optimal number and location of heaters in 2-D radiant enclosures composed of specular and diffuse surfaces using micro-genetic algorithm

In this study, a combinatorial optimization methodology has been presented for determining the optimal number and location of equally powered heaters over some parts of the boundary, called the heater surface, to satisfy the desired heat flux and temperature profiles over the design surface while keeping the total heaters power constant but floating the number of heaters. In a typical enclosure, candidate locations were numerous for placing the heaters. The optimal number and location could be found by checking among all the possible combinations of heater power ranges and locations on the heater surface. The possibility of checking only a small portion of the total search space was increasingly desirable for finding an overall optimal solution. Micro-genetic algorithm was a candidate method which displayed a significant potential in achieving that task. Micro-genetic algorithm was used to minimize an objective function which was expressed by the sum of square errors between estimated and desired heat fluxes on the design surface. Radiation element method by ray emission model (REM²) was used to calculate the radiative heat flux on the design surface. It enabled us to handle the effects of specular surfaces and blockage radiation due to enclosure geometry. The capabilities of this methodology were demonstrated by finding the optimal number and position of heaters in two irregular enclosures. The effects of refractory surface characteristics (i.e., diffuse and/or specular) on the optimal solution have been studied in detail. The results show that the refractory surface characteristics have profound effects on the optimal number and location of heaters.     

Influence of pH and flow on the polarisation behaviour of pure magnesium in borate buffer solutions

The influence of pH and flow on the polarisation and impedance behaviour of pure Mg was investigated in 0.6 wt% NaCl borate buffer solutions at pH 6.7, 7.6, and 9.3 using a rotating electrode. The existence of flow prevented the accumulation of the corrosion product and promoted uniform corrosion, leading to an increase of the anodic current density and a decrease of the impedance regardless of the pH of the bulk solution. The influence of the pH did not obviously appear under the static condition, whereas, under the dynamic condition, the anodic current density at pH 6.7 and 7.6 was higher than that at pH 9.3. This result suggests that pH near the surface can be buffered at the pH of bulk solution by borate buffer with the acceleration of ion diffusion.     

Computations of metal-covered C60 and C70

Semiempirical quantum-chemical PM3 calculations are reported for a new class of exohedral metallo-fullerenes – metal-coated or metal-covered fullerenes: C₆₀M_n and C₇₀M_n. The exohedral species have been observed in gas phase, however, their geometrical and electronic structures are not known yet. Relatively-even metal-atom distributions over the fullerene rings are considered – such regular forms are computed for M = Be, Mg, Al. Three selected types of stoichiometries are treated in particular: C₆₀M₁₂/C₇₀M₁₂ (metal atoms above all pentagons), C₆₀M₂₀/C₇₀M₂₅ (metal atoms above all hexagons), and C₆₀M₃₂/C₇₀M₃₇ (metal atoms above all rings). If an odd number of electrons should result (Al), the related cation is computed, or one metal atom added or removed. This interesting arrangement above the rings is possible only for some types of atoms, while other elements are localized above bonds or atoms, or inside the cage, or even react and destroy the cage. Other limitation comes from the parametrization of the computational technique used – the PM3 semiempirical method is parametrized only for some selected metals. Metal-layer atomization heats are suggested as a stability measure. Structural characteristics are also presented and interesting reductions of the cage symmetry are found. Their relationship to Jahn–Teller effect is discussed. The metal covered fullerenes can represent models for metal catalysis in the nanotube synthesis and could eventually lead to new interesting materials.     

Electronic structure of wurtzite- and zinc blende-GaN studied by angle-resolved photoemission

The valence band structures of both wurtzite- and zinc blende-GaN were investigated by angle-resolved photoemission spectroscopy. It was found the k dispersions of the upper valence bands show band structures corresponding to wurtzite or zinc blende structure. In wurtzite-GaN, band width of the upper valence band is 6.7 eV in good agreement with the theoretically predicted value. However, the binding energy of Ga 3d level was found to be 15.7 eV relative to the valence band maximum, which is about 2 eV higher binding energy than those predicted by local density approximation calculations. In zinc blende-GaN, some discrepancies in the binding energy of the topmost bands around the valence band maximum was observed. We discuss the cause of these discrepancies by taking into account the strain effect.     

Profiling the Biological Characteristics and Transitions through Upper Tract Tumor Origin,Bladder Recurrence,and Muscle-Invasive Bladder Progression in Upper Tract Urothelial Carcinoma

To evaluate biological characteristics and transitions of upper tract urothelial carcinoma (UTUC) through metachronous bladder tumors after radical nephroureterectomy (RNU), we conducted immunohistochemical (IHC) staining of tumor specimens of UTUC tumor origin, non-muscle-invasive bladder cancer (NMIBC) and MIBC progressed after intravesical recurrence (IVR), and bladder primary MIBC. Fibroblast growth factor receptor 3 (FGFR3), p53, cytokeratin 5/6 (CK5/6), and CK20 were stained to examine expression rates. After expression assessment with heatmap clustering, the overexpression of four biomarkers from UTUC origin to metachronous MIBC progression was analyzed with clinicopathological variables. We found that high CK20 and low CK5/6 expression were both observed in UTUC tumor origin and subsequent NMIBC after RNU. By investigating molecular expression in the IVR specimen, we observed that low pT stage bladder recurrence occupied the majority of CK20 high CK5/6 low expression, but would change to CK20 low CK5/6 high expression as it progressed to MIBC. UTUC metachronous MIBC has different characteristics compared with bladder primary MIBC, which comprises favorable biological features such as high FGFR3 expression, and follows favorable prognosis compared to those without FGFR3 expression. The present study demonstrated that the biological characteristics of UTUC tumor origin shifts from luminal to basal-like features with progression to MIBC, but FGFR3 expression taken over from UTUC origin may comprise a favorable entity compared to primary MIBC.