Effect of ß-casomorphin-7 on myocardial hypertrophy in hyperthyroidism-induced cardiomyopathy.

OBJECTIVE: The purpose of this study was to investigate the effect of ß-casomorphin-7 (ß-CM-7) on myocardial hypertrophy (MH) in hyperthyroidism-induced cardiomyopathy in vivo and in vitro. MATERIALS AND METHODS: Thirty C56BL/6 mice were randomly divided into three groups: control group, hyperthyroidism group, and ß-CM-7 treatment group. An animal model of cardiac hypertrophy of hyperthyroid heart disease (HHD) was constructed by continuous intraperitoneal injection of 100 µg of L-thyroxine (L-Thy) for 28 days, and the serum TT3 and TT4 concentrations were measured. After that, myocardial specimens were collected to measure left and right ventricular MH index, and the myocardial cell structure was observed under hematoxylin and eosin (HE) staining. Thereafter, Masson staining was adopted to determine collagen volume fraction, and hydroxylamine method was used to measure superoxide dismutase (SOD) activity, Meanwhile, DTNB direct method was applied to measure GSH-Px activity, thio-malonylurea method was utilized to measure malondialdehyde (MDA) content, and the level of reactive oxygen species (ROS) was detected by flow cytometry. Finally, the expressions of oxidative stress (OS) and inflammation-related factors in vivo and the nuclear factor-κB (NF-κB) pathway in vitro were detected by Western blot and quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: Compared with those in control group, TT3 and TT4 were remarkably increased, the structure of myocardial cells was disordered, the interstitial fibrosis and the ventricular MH index were significantly increased, the OS and inflammatory responses were increased, and the NF-κB pathway was activated in the Hyperthyroidism group. In the ß-CM-7 group, the content of TT3 and TT4 was decreased, the myocardial cell structure was slightly disturbed, the fibrosis and the ventricular MH index were reduced, OS and inflammatory response were reduced, and the NF-κB pathway was inhibited. CONCLUSIONS: ß-CM-7 can prevent and treat MH in mice with L-Thy-induced HHD probably through regulating the NF-κB signaling pathway.

Ultrafast Transient Spectroscopy of Trans-Polyacetylene in the Midinfrared Spectral Range.

Trans-polyacetylene [t-(CH)_{x}] possesses twofold ground state degeneracy. Using the Su-Schrieffer-Heeger Hamiltonian, scientists predicted charged solitons to be the primary photoexcitations in t-(CH)_{x}; this prediction, however, has led to sharp debate. To resolve this saga, we use subpicosecond transient photomodulation spectroscopy in the mid-IR spectral range (0.1-1.5 eV) in neat t-(CH)_{x} thin films. We show that odd-parity singlet excitons are the primary photoexcitations in t-(CH)_{x}, similar to many other nondegenerate π-conjugated polymers. The exciton transitions are characterized by two photoinduced absorption (PA) bands at 0.38 and 0.6 eV, and an associated photoluminescence band at ∼1.5 eV having similar polarization memory. The primary excitons undergo internal conversion within ∼100 fs to an even-parity (dark) singlet exciton with a PA band at ∼1.4 eV. We also find ultrafast photogeneration of charge polarons when pumping deep into the polymer continuum band, which are characterized by two other PA bands in the mid-IR and associated photoinduced IR vibrational modes.

Analysis on difference in gastrointestinal hormone levels of patients with the history of diabetes and concurrent nephropathy and study on the role of liraglutide.

OBJECTIVE: To compare the difference in the gastrointestinal hormone levels of the patients with the history of diabetes and concurrent nephropathy and investigate the clinical effect of liraglutide in the treatment of diabetic nephropathy (DN). PATIENTS AND METHODS: 42 cases of patients with DN admitted in our hospital from April 2010-May 2015 were selected and divided into phase I-II group (group A, n = 22) and phase III-IV group (group B, n = 20) according to DN phases and 20 cases of patients with diabetes rather than nephropathy admitted in our hospital during the same period were selected as the control group, all of whom underwent the routine biochemical test and gastrointestinal hormone test, the differences in gastrin (GAS), motilin (MTL) and glucagon (GLC) of DN patients were compared at different phases, the gastric emptying test was carried out on them and the gastric emptying time was recorded. All patients were treated with liraglutide and the changes in fasting blood glucose (FBG), glycosylated hemoglobin (HbAlc), serum creatinine (Cr), blood urea nitrogen (BUN), insulin (FINS) and insulin resistance level (HOMA-IR) were tested before treatment and after 10 weeks' treatment, the changes in the tumor necrosis factor (TNF-α), interleukin -6 (IL-6) and transforming growth factor (TGF-ß1) were determined, and the change in the gastrointestinal hormone levels of patients was recorded after treatment. RESULTS: (1) the GAS, MTL, GLC and gastric emptying time in group B were higher than those in group A and the control group (p < 0.05), and the above indicators in group A were higher (p < 0.05); (2) after 10 weeks' treatment, the gastrointestinal hormone levels in the three groups were reduced and the gastric emptying time was shortened, the difference was statistically significant (p < 0.05) compared with those before treatment, after 10 weeks' treatment, the GAS, MTL, GLC and gastric emptying time in group B were higher than group A and the control group, those in group A were higher than control group (p < 0.05); (3) before treatment, the comparative differences in FBG, HbAlc, FINS and HOMA-IR among the three groups were not statistically significant (p > 0.05), and after 10 weeks' treatment, the differences in FBG, HbAlc and HOMA-IR among three groups were reduced and FINS was increased, the difference in those between before treatment and after treatment was statistically significant (p < 0.05) and the comparative difference among the three groups was not statistically significant (p > 0.05); (4) before treatment, Cr and BUN levels in group A and group B were higher than the control group (p < 0.05), after 10 weeks' treatment, the Cr and BUN levels among three groups were significantly decreased (p < 0.05), Cr and BUN in group A and group B were higher than the control group, cr and BUN levels in group B were higher than group A (p < 0.05); (5) before treatment, the difference by comparing IL-6, TNF-α and TGF-ß1 among three groups were not statistically significant (p > 0.05), after 10 weeks' treatment, the indicators in the three groups were decreased significantly (p < 0.05), but the comparative difference among the three groups were not statistically significant (p > 0.05); (6) the difference by comparing the efficiencies among the three treatment was not statistically significant (p > 0.05). CONCLUSIONS: There are some correlations between the gastrointestinal hormone levels and the degree of renal impairment of DN patients. Good results will be achieved by applying liraglutide in intervention with different phases of DN and DM patients, which cannot only regulate the gastrointestinal hormone levels and lower the blood sugar levels of patients, but can also reduce the insulin resistance and delay the process of renal damage.

Ultrafast intersystem-crossing in platinum containing π-conjugated polymers with tunable spin-orbit coupling.

The development of efficient organic light-emitting diodes (OLED) and organic photovoltaic cells requires control over the dynamics of spin sensitive excitations. Embedding heavy metal atoms in π-conjugated polymer chains enhances the spin-orbit coupling (SOC), and thus facilitates intersystem crossing (ISC) from the singlet to triplet manifolds. Here we use various nonlinear optical spectroscopies such as two-photon absorption and electroabsorption in conjunction with electronic structure calculations, for studying the energies, emission bands and ultrafast dynamics of spin photoexcitations in two newly synthesized π-conjugated polymers that contain intrachain platinum (Pt) atoms separated by one (Pt-1) or three (Pt-3) organic spacer units. The controllable SOC in these polymers leads to a record ISC time of <~1 ps in Pt-1 and ~6 ps in Pt-3. The tunable ultrafast ISC rate modulates the intensity ratio of the phosphorescence and fluorescence emission bands, with potential applications for white OLEDs.

Below-gap excitation of pi-conjugated polymer-Fullerene blends: implications for bulk organic heterojunction solar cells.

We used a variety of optoelectronic techniques such as broadband fs transient and cw photomodulation spectroscopies, electroabsorption, and short-circuit photocurrent in bulk heterojunctions organic solar cells for studying the photophysics in pi-conjugated polymer-fullerene blends with below-gap excitation. In contrast to the traditional view, we found that below-gap excitation, which is incapable of generating intrachain excitons, nevertheless efficiently generates polarons on the polymer chains and fullerene molecules. The polaron action spectrum extends deep inside the gap as a result of a charge-transfer complex state formed between the polymer chain and fullerene molecule. With appropriate design engineering the long-lived polarons might be harvested in solar cell devices.

Ultrafast spectroscopy of excitons in single-walled carbon nanotubes.

We studied the femtosecond dynamics of photoexcitations in films containing semiconducting and metallic single-walled carbon nanotubes (SWNTs), using various pump-probe wavelengths and intensities. We found that confined excitons and charge carriers with subpicosecond dynamics dominate the ultrafast response in semiconducting and metallic SWNTs, respectively. Surprisingly, we also found from the exciton excited state absorption bands and multiphoton absorption resonances in the semiconducting nanotubes that transitions between subbands are allowed; this unravels the important role of electron-electron interaction in SWNT optics.