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3-Bromopyruvate (3-BrPA) is a promising agent that has been widely studied in the treatment of cancer and pulmonary hypertension. Rotenone is a pesticide commonly used on farms and was shown to have anti-cancer activity and delay fibrosis progression in chronic kidney disease in a recent study. However, there are few studies showing the toxicity of rotenone and 3-BrPA in the myocardium. To support further medical exploration, it is necessary to clarify the side effects of these compounds on the heart. This study was designed to examine the cardiotoxicity of 3-BrPA and rotenone by investigating electrical and structural cardiac remodeling in rats. Forty male rats were divided into 4 groups (n = 10 in each group) and injected intraperitoneally with 3-BrPA, rotenone or a combination of 3-BrPA and rotenone. The ventricular effective refractory period (VERP), corrected QT interval (QTc), and ventricular tachycardia/ventricular fibrillation (VT/VF) inducibility were measured. The expression of Cx43, Kir2.1, Kir6.2, DHPRα1, KCNH2, caspase3, caspase9, Bax, Bcl2, and P53 was detected. Masson's trichrome, TUNEL, HE, and PAS staining and transmission electron microscopy were used to detect pathological and ultrastructural changes. Our results showed that rotenone alone and rotenone combined with 3-BrPA significantly increased the risk of ventricular arrhythmias. Rotenone combined with 3-BrPA caused myocardial apoptosis, and rotenone alone and rotenone combined with 3-BrPA caused electrical and structural cardiac remodeling in rats.

Objective: Recent evidence has shown that, in heart failure (HF), clinically relevant concentrations of angiotensin-(1-7) [Ang-(1-7)] counteracts angiotensin II induced cardiac depression and produces positive inotropic effects in both left ventricle (LV) and myocytes. However, the underlying electrophysiological mechanism is unclear. We investigated the role and mechanism of Ang-(1-7) on LV myocyte L-type calcium current (ICa,L) responses in normal state and in HF. Method: We compared the effect of Ang-(1-7) (10−5 M) on ICa,L responses in isolated LV myocytes obtained from 11 rats with isoproterenol (ISO) induced HF (3 months after 170 mg/kg subcutaneous for 2 days) and from 8 age-matched normal control rats by patch clamp technique. Results: In normal myocytes, compared with baseline, superfusion of Ang-(1-7) caused no significant changes in ICa,L (8.2 ± 0.2 versus 8.0 ± 0.3 pA/pF, p= not significant). In HF myocytes, the baseline ICa,L was significantly reduced (5.3 ± 0.1 versus 8.0 ± 0.3 pA/pF, p < 0.01). Ang-(1-7) produced a 21% increase in ICa,L (6.4±0.1 versus 5.3±0.1 pA/pF, p < 0.01). Pretreatment of HF myocytes with a nitric oxide (NO) synthase inhibitor (L-NAME, 10−5 M) resulted in a significantly greater increase in ICa,L (28%, 8.4 ± 0.1 versus 6.5 ± 0.1 pA/pF, p < 0.01) during Ang-(1-7) superfusion. In contrast, during incubation with the bradykinin (BK) inhibitor HOE 140 (10−6 M), Ang-(1-7) induced increase in ICa,L was significantly decreased. The Ang-(1-7) induced increase in ICa,L was abolished by [D-Ala7]-Ang-(1-7) (A-779, 10−5 M). Conclusions: HF alters the response of ICa,L to Ang-(1-7). In normal myocytes, Ang-(1-7) has no significant effect on ICa,L. However, in HF myocytes, Ang-(1-7) increases ICa,L. These effects are mediated by the Ang-(1-7) Mas receptors and involve activation of NO/BK pathways.

A new squaraine dye Bis(4-N,N-dicarboxymethyl-2-hydroxyphenyl)squaraine (SQ) which could be used as organic photovoltaic materials, was synthesized, and its molecular structure was fully characterized by elemental analysis, IR, 1H NMR and MS. SQ exhibits strong absorption band over 600–700 nm. Addition of TiO2 colloids to the ethanol solution of SQ resulted in the increase of optical density, quenching of fluorescence and shortened fluorescence lifetime. The apparent association constant between the sensitizer and semiconductor as measured from the fluorescence quenching data, was 2427 M−1. Fluorescence lifetime measurements gave the rate constant for the electron injection process from the excited singlet of SQ to the conduction band of TiO2 nanoparticles as 2.55 × 10 8 s−1. In addition, SQ doped SiO2 gel glass slices were prepared and characterized by absorption and emission spectra.

Background: Accumulating evidence suggests that Angiotensin (A)-(1-7) exhibits cardiovascular effects that are in opposition to that of AII, thus providing protection against heart diseases. However, the exact means by which A-(1-7) affords cardioprotection are unclear. Its direct cardiac effect is not well understood. We previously showed that in heart failure (HF), AII decreases left ventricle (LV) contractility. Whether A-(1-7) may antagonize AII-induced cardiac depression, thereby contributing to its beneficial actions in HF remains to be determined. We assessed the hypothesis that A-(1-7) may produce positive modulation on [Ca 2+ ] i regulation and LV and myocyte contraction via A-(1-7) receptors, coupled with nitric oxide (NO)/bradykinin (BK)-mediated mechanism. Methods: We measured LV contractility changes after A-(1-7) (650 ng/kg, iv), which produced a 20-fold increase in plasma A-(1-7) levels, mimicking the elevations caused by angiotensin-converting enzyme inhibitor therapy in HF, and compared myocyte contractile, [Ca 2+ ] i transient ([Ca 2+ ] iT ) and I Ca,L responses to A-(1-7) (10 -5 M) in 14 rats with isoproterenol induced HF (3 months after 170 mg/kg sq for 2 days). In the subsets of cell contractile study, myocytes were pretreated to inhibit NO synthase (L-NAME, 10 -5 M), BK (HOE 140, 10 -6 M) or A-(1-7) receptor [D-Ala 7 ]-A-(1-7), 10 -5 M) followed with A-(1-7) exposure. Results: Compared with baseline, after A-(1-7), E ES (47%, 1.0 vs 0.68 mmHg/μl) and M SW (49%, 94.3 vs 62.8 mmHg) were increased, indicating enhanced LV contractility. In HF myocytes, A-(1-7) increased myocyte percent shortening (28%, 6.8% vs 5.3%), the velocity of contraction (31%, 106.4 vs 74.5 μm/sec) and relengthening (41%, 74.7vs 50.1 μm/sec) accompanied by significantly-increased [Ca 2+ ] iT (27%, 0.19 vs 0.15 pA/pF) and I Ca,L (24%, 6.3 vs 5.1pA/pF). L-NAME increased, HOE 140 decreased, and A-(1-7) receptor blockade prevented myocyte contractile responses to A-(1-7). Conclusion: In HF, clinically-relevant concentrations of A-(1-7) counteracted AII-induced cardiac depression, increased [Ca 2+ ] iT and I Ca,L , and produced positive inotropic effects in both LV and myocytes. These effects are coupled with A-(1-7) receptors and involve activation of NO/BK pathways.

Using a 1∶1 tetrakis(4-N-hexadecylpyridiniumyl)porphyrin/anthraquinone (TC16PyP(4)/AnQ) mixture as film-forming material, the structure and properties of TC16PyP(4)/AnQ mixed monolayers or LB films were studied by π–A isotherms, UV–VIS absorption spectra, and low-angle X-ray diffraction (LAXD). The experimental results indicate that the TC16PyP(4)/AnQ mixture has good film-forming properties at the air/water interface. The TC16PyP(4)/AnQ mixed monolayer can be transferred to glass, quartz or SnO2 optically transparent electrode (OTE) substrates. Most AnQ molecules are incorporated into the cavities between the long alkyl chains of TC16PyP(4) molecules in the mixed monolayer or in LB films. The TC16PyP(4)/AnQ mixed LB films can be regarded as a two-dimensional host–guest system and show good stability and periodicity. The photovoltaic behaviour of an electrochemical cell containing a TC16PyP(4)/AnQ LB film, deposited on an SnO2 OTE, was also investigated. The photocurrent and photovoltage are apparently lower than those for the photocell of pure TC16PyP(4) LB films due to the incorporation of AnQ.

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 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.

Both the Langmuir and Langmuir-Blodgett films of a C[sub 60] derivative C[sub 60](C[sub 4]H[sub 8]N[sub 2]) at the air-water interface have been prepared. The second-order molecular hyperpolarizability is determined to be (3.6 [+-] 1.2) x 10[sup 29] esu. 29 refs., 3 figs., 1 tab.

A series of lanthanoid complexes (E)-1-ferrocenyl-2-(N-hexadecylpyridinium-4-yl)ethylene tetrakis(dibenzoylmethanato)lanthanoides(III) (La, Nd, Dy and Yb) have been newly synthesized for second-order nonlinear optical LB materials. The monolayer behaviors at the air-water interface, ultraviolet spectra and second-harmonic generation (SHG) of the films have been reported. The values of second-order molecular hyperpolarizability β of the complexes were estimated to be (1.37–1.58) × 10−28 esu.