Here, we reported that a new carbon electrode prepared with an activated carbon was superior to a Pt sputtered electrode as the counter electrode of dye-sensitized solar cells. The photovoltaic ...performance was largely influenced by the roughness factor of carbon electrode. The open-circuit voltage increased by about 60
mV using the carbon counter electrode compared to the Pt counter electrode because of positive shift of the formal potential for I
3
−/I
− couple.
Erythropoietin receptor (EpoR) is expressed in the central nervous system (CNS), however, no clear consensus has been obtained whether Epo acts as a prosurvival factor in neurons. Because retinal ...ganglion cell (RGC) death is a common cause of reduced visual function in several ocular diseases, we explored whether Epo might potentially be beneficial in protecting RGCs from glutamate and nitric oxide (NO)-induced cytotoxicity, using isolated RGCs by a two-step panning method. Brain-derived neurotrophic factor (BDNF) was used as a positive control. EpoR mRNA was expressed in isolated RGCs, and EpoR protein was expressed on the RGCs in the normal and ischemic retinas. Epo had less potential to improve the survival of primary RGCs in serum-free medium than BDNF. In these cells, BDNF, but not Epo, downregulated the expression of Bim, a proapoptotic Bcl-2 family member that plays a key role in cytokine-mediated cell survival, suggesting a possible mechanism for this difference. When RGCs were cultured with glutamate or an NO-generating reagent, the survival of RGCs was compromised, and Bcl-2 expression was decreased in these cells. Both Epo and BDNF significantly reduced RGC death induced by glutamate and NO. In agreement with this, these factors reversed the Bcl-2 expression. These findings suggest that Epo may be a potent neuroprotective therapeutic agent for the treatment of ocular diseases that are characterized by RGC death.
In the blended solid of poly(3-hexylthiophene-2,5-diyl) (P3HT) and porphyrin (TPP)/TiO2 p-n hetero-junction solar cells, a photo-induced charge transfer between P3HT and TPP accelerated the charge ...separation in the depletion layer formed at the P3HT+TPP/TiO2 interface, enhancing the photovoltaic properties. For the blended cell containing zinc porphyrin as TPP, the energy conversion yield of 0DDT26% was obtained under the illumination of solar simulated light AM1DDT5-100mW/cm2.
A water-soluble externally (HCl)-doped conducting polyaniline (ED-SPAN) is prepared by such a simple synthetic method that emeraldine salts are sulfonated by chlorosulfonic acid in dichloroethane at ...80°C and subsequently hydrated in water at 100°C. Sulfonating any emeraldine salts (counter anion X
− = Cl
−, SO
4
2−, and BF
4
−) or emeraldine base results in the production of HCl-doped sulfonated polyaniline, where HCl dopant from hydrolysis of chlorosulfonic group exchanges with the original dopant. The degree of sulfonation, namely, sulfur-to-nitrogen (S/N) ratio, can be controlled by adjusting the amount of chlorosulfonic acid. With increasing S/N ratio from 0.65 to 1.3, the solubility in neutral water increases from 22 to 88 g/l and the four-probe conductivity for a compressed pellet decreases from 0.023 to 1.7 × 10
−5 S/cm, showing sulfonation-induced undoping.
An enhanced photocurrent was obtained in an Al/porphyrin-sensitized regioregular polythiophene (PTh) Schottky-barrier cell when the top energy level of the valence band of PTh solid was more negative ...than the HOMO energy level of porphyrin. However, when ortho-substituted meso-phenylporphyrins were employed, the photocurrent enhancement decreased to about half compared to the case when nonsubstituted meso-phenylporphyrins were used. We conclude from these results that both a larger thermodynamic driving force for a photoinduced hole transfer from porphyrin to PTh and a closer distance between the two conjugating planes of porphyrin and PTh are necessary to obtain a larger photocurrent.
We investigated the usefulness of 24-h Holter monitoring for identification of myocardial involvement in 38 patients with sarcoidosis, including 12 patients with cardiac sarcoidosis, and 58 healthy ...controls. Ventricular ectopic beats (VEB) ≥100 beats per day were detected in 8 (67 percent) of 12 patients with cardiac sarcoidosis, in 2 (8 percent) of 26 patients without cardiac sarcoidosis, and in 3 (5 percent) of 58 healthy controls. Holter monitoring was associated with a sensitivity of 67 percent and a specificity of 62 percent for cardiac sarcoidosis in the overall study population. In patients with sarcoidosis, specificity was 80 percent. Lown's grade 4 A and 4 B VEBs were detected in 8 (67 percent) of 12 patients with cardiac sarcoidosis, in 2 (8 percent) of 26 patients with sarcoidosis without cardiac involvement, and in 2 (3 percent) of 58 controls. Holter monitoring was associated with a sensitivity of 67 percent and a specificity of 80 percent for identification of cardiac involvement in patients with systemic sarcoidosis. Our findings suggest that 24-h Holter monitoring provides a convenient and inexpensive means of noninvasive screening for cardiac involvement in generalized sarcoidosis, even in patients and outpatients who are without symptoms.
The purpose of this study was to determine the optimal intensity of exercise necessary to prevent the postmenopausal bone loss on the basis of anaerobic threshold (AT). Thirty-three postmenopausal ...women were randomized to control (group C: n = 12) or two exercise groups (group H and group M). All women performed a treadmill exercise test, and the AT was measured by expired gas analysis. The exercise regimen consisted mainly of walking at a speed that kept the exercise heart rate above the AT (group H: n = 12) or below the AT (group M: n = 9). Exercise was performed for 30 minutes, three times a week for 7 months. The bone mineral density (BMD) of the lumbar vertebrae was measured using dual energy X-ray absorptiometry. The BMD level in group C decreased by 1.7 +/- 2.7%, but there was a significant increase of 1.1 +/- 2.9% in group H. In group M there was a decrease of 1.0 +/- 3.1% which did not differ from group C. In group C, serum osteocalcin and urinary hydroxyproline excretion were significantly increased, but no changes were seen in either of the exercise groups. Urinary calcium significantly decreased in the exercise groups. We conclude that short-term (7 months) exercise with intensity above the AT is safe and effective in preventing postmenopausal bone loss.
To clarify the adsorption mechanism of proteins onto calcium hydroxyapatite (Hap), the present study measured adsorption (ΔH ads) and desorption (ΔH des) enthalpies of bovine serum albumin (BSA; ...isoelectric point (iep) 4.7, molecular mass (M s) 67200 Da, acidic protein), myoglobin (MGB; iep = 7.0, M s = 17800 Da, neutral protein), and lysozyme (LSZ; iep = 11.1, M s = 14600 Da, basic protein) onto Hap by a flow microcalorimeter (FMC). Five kinds of large platelike particles of CaHPO4·2H2O (DCPD) after hydrolyzing at room temperature with different concentrations of NaOH aqueous solution (NaOH) for 1 h were used. DCPD converted completely to Hap after treatment at NaOH ≥ 2%, and the crystallinity of Hap was increased with an increase in NaOH up to 10%. The amounts of protein adsorbed (Δn ads) and desorbed (Δn des) were measured simultaneously by monitoring the protein concentration downstream from the FMC with a UV detector. The Δn ads values were also measured statically by a batch method in each system. The Δn ads values measured by the FMC and static measurements fairly agreed with each other. Results revealed that Δ was decreased with an increase in NaOH; in other words, Δ was decreased with the improvement of Hap's crystallinity, suggesting that the BSA adsorption readily proceeded onto Hap. This fact indicated a high affinity of Hap to protein. This affinity was further recognized by Δ because its positive value was increased by increasing NaOH. These opposite tendencies in Δ and Δ revealed that Hap possessed a high adsorption affinity to BSA (i.e., enthalpy facilitated protein adsorption but hindered its desorption). The fraction of BSA desorption was also decreased with an increase in NaOH, confirming the high affinity of Hap to protein. Similar results were observed on the LSZ system, though the enthalpy values were smaller than those of BSA. In the case of neutral MGB, Δ also exhibited results similar to those of the BSA and LSZ systems. However, due to its weak adsorption by the van der Waals force, Δ was small and almost zero at NaOH ≥ 2%. Hence, the fraction of MGB desorption was less dependent on NaOH.
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