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Background Angiotensin-(1–12) [Ang-(1–12)] is a renin-independent precursor for direct angiotensin-II production by chymase. Substantial evidence suggests that heart failure (HF) may alter cardiac Ang-(1–12) expression and activity; this novel Ang-(1–12)/chymase axis may be the main source for angiotensin-II deleterious actions in HF. We hypothesized that HF alters cardiac response to Ang-(1–12). Its stimulation may produce cardiac negative modulation and exacerbate left ventricle (LV) systolic and diastolic dysfunction. Methods and results We assessed the effects of Ang-(1–12) (2 nmol/kg/min, iv, 10 min) on LV contractility, LV diastolic filling, and LV-arterial coupling (AVC) in 16 SD male rats with HF-induced by isoproterenol (3 mo after 170 mg/kg sq. for 2 consecutive days) and 10 age-matched male controls. In normal controls, versus baseline, Ang-(1–12) increased LV end-systolic pressure, without altering heart rate, arterial elastance (EA), LV end-diastolic pressure (PED), the time constant of LV relaxation (τ) and ejection fraction (EF). Ang-(1–12) significantly increased the slopes (EES) of LV end-systolic pressure (P)-volume (V) relations and the slopes (MSW) of LV stroke wok-end-diastolic V relations, indicating increased LV contractility. AVC (quantified as EES/EA) improved. In contrast, in HF, versus HF baseline, Ang-(1–12) produced a similar increase in PES, but significantly increased τ, EA, and PED. The early diastolic portion of LV P V loop was shifted upward with reduced in EF. Moreover, Ang-(1–12) significantly decreased EES and MSW, demonstrating decreased LV contractility. AVC was decreased by 43%. Conclusions In both normal and HF rats, Ang-(1–12) causes similar vasoconstriction. In normal, Ang-(1–12) increases LV contractile function. In HF, Ang-(1–12) has adverse effects and depresses LV systolic and diastolic functional performance.

AIMS: G protein-coupled estrogen receptor 30 (GPR30) activation by its agonist, G1, exhibits beneficial actions in female with heart failure (HF). Recent evidence indicates its cardiovascular benefits may also include male as well. However, whether and how GPR30 activation may limit HF progression and have a salutary role in males is unknown. We hypothesized that chronic G1 treatment improves LV and cardiomyocyte function, [Ca(2+)](i) regulation and β-adrenergic reserve, thus reversing HF progression in male. MAIN METHODS: We compared left ventricle (LV) and myocyte function, [Ca(2+)](i) transient ([Ca(2+)](iT)) and β-AR modulation in control male mice (12/group) and isoproterenol-induced HF (150 mg/kg s.c. for 2 days). Two weeks after isoproterenol injection, HF mice received placebo, or G1 (150 μg/kg/day s.c. mini-pump) for 2 weeks. KEY FINDINGS: Isoproterenol-treated mice exhibited HF with preserved ejection fraction (HFpEF) at 2-weeks and progressed to HF with reduced EF (HFrEF) at 4-weeks, manifested by significantly increased LV time constant of relaxation (τ), decreased EF and mitral flow (dV/dt(max)), which were accompanied by reduced myocyte contraction (dL/dt(max)), relaxation (dR/dt(max)) and [Ca(2+)](iT). Acute isoproterenol-superfusion caused significantly smaller increases in dL/dt(max), dR/dt(max) and [Ca(2+)](iT). G1 treatment in HF increased basal and isoproterenol-stimulated increases in EF and LV contractility of E(ES). Importantly, G1 improved basal and isoproterenol-stimulated dL/dt(max), dR/dt(max) and [Ca(2+)](iT) to control levels and restored normal cardiac β-AR subtypes modulation. SIGNIFICANCE: Chronic G1 treatment restores normal myocyte basal and β-AR-stimulated contraction, relaxation, and [Ca(2+)](iT), thereby reversing LV dysfunction and playing a rescue role in a male mouse model of HF.

An increase in oxidative stress is an important pathological mechanism of heart injury induced by doxorubicin (DOX). Tranilast is an anti-allergy drug that has been shown to possess good antioxidant activity in previous studies. The overexpression and secretion of chymase by mast cells (MCs) increase the pathological overexpression of angiotensin II (Ang II), which plays a crucial role in myocardial hypertrophy and the deterioration of heart disease. The MC stabilizer tranilast (N-(3,4-dimethoxycinnamoyl) anthranilic acid; tran) prevents mast cells from degranulating, which may reduce DOX-induced Ang II synthesis. Therefore, in the present study, we hypothesized that tranilast will protect rats from DOX-induced myocardial damage via its antioxidant activity, thereby inhibiting Ang II expression. Thirty male Wistar rats were divided into three groups (n = 10 in each group) that received DOX, a combination of DOX and tranilast or saline (the control group) to test this hypothesis. Tranilast suppressed chymase expression, reduced Ang II levels and prevented the myocardial hypertrophy and the deterioration of heart function induced by DOX. Based on the findings of the present study, the suppression of chymase-dependent Ang-II production and the direct effect of tranilast on the inhibition of apoptosis and fibrosis because of its antioxidant stress capacity may contribute to the protective effect of tranilast against DOX-induced myocardial hypertrophy.

Background: In addition to its well-known vasodilating and natriuretic actions, C-type natriuretic peptide (CNP), has been viewed as an endogenous inhibitor of the renin-angiotensin system, but its...

Photochromism of fulgide with dicyanomethylene a, doped in PMMA matrix, has been investigated. It showed that fulgide a undergoes photoisomerization reaction in PMMA film and exhibits fast response, high sensitivity as well as non-destructive readout. Besides, four-level recording of photochromic compound a used as recording media has also explored with 780 nm laser beam.

The Langmuir and Langmuir–Blodgett (LB) films of a novel crowned [60]fullero-pyrrolidine(CFP) were produced in different conditions. Macroscopic second-harmonic generation of the LB film was investigated by means of AM1 Hamiltonian as well as experiments. The monolayer LB film displayed a periodic fringe pattern. A linear dependence of second-harmonic intensity on the number of layers was observed. The second-order molecular susceptibility χ (2) and hyperpolarizability β were evaluated to be 3.2×10 −8 and 8.3×10 −29 esu .

The photovoltaic behavior of an electrochemical cell of TC 16 PyP(4) monolayer, deposited on SnO 2 optically transparent electrodes (SnO 2 OTE) by the Langmuir–Blodgett (LB) technique was investigated. The photocell was able to generate photocurrent, which increase in the presence of electron donors or acceptors in the KCl electrolyte solution, indicating that the photovoltaic effect of TC 16 PyP(4) perhaps originates from the photo-induced charge transfer between TC 16 PyP(4) molecules and SnO 2 semi-conductor. Moreover, the orientation of TC 16 PyP(4) in monolayer or LB films was also studied by π –A isotherm and polarized absorption spectrum. The result showed that the porphyrin macroring was oriented with an angle of about 25° against the aqueous surface as well as the substrate plane.

The photoelectrochemical behavior of mercapto-substituted hypocrellin B (MSHB), deposited on SnO2 optically transparent electrodes by means of the Langmuir–Blodgett technique, have been investigated. Addition of electron donors leads to a remarkable enhancement of the photocurrents and photovoltages. Effects of the electron donor concentration, LB film layers, and illumination time on the magnitude of the photocurrent were studied in detail. The usefulness of hypocrellin derivatives as efficient organic photoelectrical conversion materials is suggested.

Photophysical properties (absorption spectra, fluorescence spectra, lifetimes and quantum yields) have been studied for several amphiphilic porphyrins bearing hydrophilic pyridinium and hydrophobic long-chain alkyl groups in different media. These amphiphilic porphyrins are characterized by reduced fluorescence quantum yields, aggregating appreciably in nonpolar solvents and biexponential fluorescence decay. The observed biexponential fluorescence decay of these porphyrin derivatives can be interpreted in terms of mixing of the S1 and a CT state in which an electron is transferred from the porphyrin core to the electron-deficient pyridinium group.

An amphiphilic lanthanide complex, ( E )-1-methyl-4-(2-(4-(dihexadecylamino)phenyl)azo)pyridinium tetrakis(1-phenyl-3-methyl-4-benzoyl-5-pyrazolonato)lanthanum(III), has been synthesized. It forms a stable Langmuir monolayer film on a pure water subphase (pH 5.6, 18°C) when spread from a chloroform solution. Langmuir-Blodgett (LB) films were prepared by transferring the monolayers onto hydrophilic substrates of quartz and calcium fluoride with a transfer ratio close to unity. From a second-harmonic generation measurement, the second-order molecular hyperpolarizability β of the complex was estimated to be about 1.4 × 10 −47 C m 3 V −2 , which is one of the largest values for azo-based, second-order non-linear optical materials reported so far. The infrared and variable-temperature ultraviolet spectra of the film are also reported.

Three europium complexes 1-methyl-4-octadecylpyridinium tetrakis(α-thenoyl trifluoroacetonato) europium(III), tris(α-thenoyl trifluoroacetonato) mono-(9-(4-hexadecylanilino)-4,5-diazafluorene) europium(III), and tris(α-thenoyltrifluoro acetonato) mono(2, 9-dimethyl-4, 7-diphenyl-1, 10-phenanthroline) europium(III) have been newly synthesized. They were capable of forming stable Langmuir films on pure water subphase(pH 5.6, 18 °C) with collapse pressures of 39.0, 50.0 and 20.5 mN/m, respectively. Langmuir-Blodgett films of these complexes have been prepared and studied by surface pressure-area isotherms, ultraviolet, fluorescent spectroscopy, fluorescent lifetime measurements and second-harmonic generation.

Two strong fluorescent amphiphilic europium-dibenzoylmethane complexes, hexadecyltrimethyl ammonium tetrakis (dibenzoylmethane) europium (A) and octadecyltriethyl ammonium tetrakis (dibenzoylmethane) europium (B), were synthesized and characterized by FT-IR, UV-vis, DTA-TG analysis and X-ray diffraction. Both of them could form stable Langmuir films at the air-water interface and the Langmuir film of A can be easily transferred onto hydrophilic substrates to build up Langmuir-Blodgett (LB) films. The LB film of A has a good layered structure, as confirmed by its low-angle X-ray diffraction. The fluorescence spectra and fluorescence lifetimes of the LB films were quite different from those of their corresponding solid powders and solutions.

An amphiphilic zinc phthalocyanine (AmZnPc) containing long alkyl chains covalently attached to the positively charged macroring was synthesized. A monolayer of AmZnPc with equimolar meso-tetrakis-(4-tolyl)porphine (TTP) was spread on water from chloroform solution and transferred onto CaF 2 slides. Multilayers were also built up on these substrates. Surface pressure-area isotherms and UV—visible absorption spectra showed that the porphyrin molecules are arranged in the cavity between the long alkyl chains of AmZnPc in one layer of the Langmuir—Blodgett film. Polarized UV—visible spectroscopy indicated that there is no anisotropy in the layer plane and the AmZnPC macroring plane lies nearly parallel to the substrate surface.

The effect of the gas environment on the second harmonic generation of Langmuir-Blodgett films of non-linear material has been studied. It has been found that the gas environment in general had a strong effect on the structure and the non-linear optical property of the films. The phenomenon has a few implications for the applications of the non-linear optical material films.

Four kinds of amphiphilic rare earth complexes containing the new chromophore: 4-[(4-N,N'-diethylamino)phenyl)azo]-1-methyl-pyridinium-Tetrakis(4-benzoyl-1-phenyl-3-methyl-pyrazolone-5) Dysprosium (compound A), 4-[(4-N,N'-(diethylamino)phenyl)azo]-1-methyl-pyridinium-Tri(4-benzoyl-1-phenyl-3-methyl-pyrazolone-5)-(4-hexadecanoyl-1-phenyl-3-methyl Pyrazolone5)Dysprosium(compound B), 4-[(4-N,N'-diethylamino)phenyl)azo]-1-methyl-pyridinium-Tetrakis(2-thenoyl-trifluoroacetone)Dysprosium (compound C) and 4-[(4-N,N'-(diethylamino)phenyl)azo]-1-methyl-pyridinium-Tri(2-thenoyl-trifluoroacetone)-(4-hexadecanoyl-1-phenyl-3-methyl-pyrazolone-5 Dysprosium (compound D), and their iodide (compound E), were synthesized. The film-forming properties of compound A and B are good while compounds C, D and E cannot form stable Langmuir film. The second-order molecular hyperpolarizability β of the rare earth complexes were evaluated to be 1.3×10 −28 e.s.u. and 5.9×10 −28 e.s.u. for compounds A and B respectively.

The amphiphilic strong luminescence europium complex given in the title has been synthesized. Three isotherms at different temperatures were measured and the 15°C one has two different solid phases, indicating two kinds of molecular arrangements on the water surface. The monolayer was transferred on different hydrophilic pretreated plates using LB technique for different purposes. The LB films were characterized by IR, UV-vis and luminescence spectra.