Rice Bran Extract Suppresses High-Fat Diet-Induced Hyperlipidemia and Hepatosteatosis through Targeting AMPK and STAT3 Signaling

Rice bran, a by-product of rice milling, is abundant in bioactive molecules and is highly recognized for its health-promoting properties, particularly in improving metabolic conditions. Building on this knowledge, we aimed to optimize the extraction conditions to maximize the functional efficacy of rice bran extract (RBE) and further validate its impact on lipid metabolism. We found that the optimized RBE (ORBE) significantly suppressed high-fat diet-induced weight gain, hyperlipidemia, and hepatosteatosis in mouse models. ORBE treatment not only suppressed lipid uptake in vivo, but also reduced lipid accumulation in HepG2 cells. Importantly, we discovered that ORBE administration resulted in activation of AMPK and inhibition of STAT3, which are both crucial players in lipid metabolism in the liver. Collectively, ORBE potentially offers promise as a dietary intervention strategy against hyperlipidemia and hepatosteatosis. This study underlines the value of optimized extraction conditions in enhancing the functional efficacy of rice bran.

Attenuated benzodiazepine-sensitive tonic GABAA currents of supraoptic magnocellular neuroendocrine cells in 24-h water-deprived rats

In supraoptic nucleus (SON) magnocellular neurosecretory cells (MNCs), γ-GABA, via activation of GABAA receptors (GABAA Rs), mediates persistent tonic inhibitory currents (Itonic ), as well as conventional inhibitory postsynaptic currents (IPSCs, Iphasic ). In the present study, we examined the functional significance of Itonic in SON MNCs challenged by 24-h water deprivation (24WD). Although the main characteristics of spontaneous IPSCs were similar in 24WD compared to euhydrated (EU) rats, Itonic , measured by bicuculline (BIC)-induced Iholding shifts, was significantly smaller in 24WD compared to EU rats (P < 0.05). Propofol and diazepam prolonged IPSC decay time to a similar extent in both groups but induced less Itonic in 24WD compared to EU rats, suggesting a selective decrease in GABAA receptors mediating Itonic over Iphasic in 24WD rats. THIP (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol), a preferential δ subunit agonist, and L-655,708, a GABAA receptor α5 subunit selective imidazobenzodiazepine, caused a significantly smaller inward and outward shift in Iholding , respectively, in 24WD compared to EU rats (P < 0.05 in both cases), suggesting an overall decrease in the α5 subunit-containing GABAA Rs and the δ subunit-containing receptors mediating Itonic in 24WD animals. Consistent with a decrease in 24WD Itonic , bath application of GABA induced significantly less inhibition of the neuronal firing activity in 24WD compared to EU SON MNCs (P < 0.05). Taken together, the results of the present study indicate a selective decrease in GABAA Rs functions mediating Itonic as opposed to those mediating Iphasic in SON MNCs, demonstrating the functional significance of Itonic with respect to increasing neuronal excitability and hormone secretion in 24WD rats.

Nonlinear dynamics of domain-wall propagation in epitaxial ferroelectric thin films

We investigated the ferroelectric domain-wall propagation in epitaxial Pb(Zr,Ti)O3 thin film over a wide temperature range (3-300 K). We measured the domain-wall velocity under various electric fields and found that the velocity data is strongly nonlinear with electric fields, especially at low temperature. We found that, as one of surface growth issues, our domain-wall velocity data from ferroelectric epitaxial film could be classified into the creep, depinning, and flow regimes due to competition between disorder and elasticity. The measured values of velocity and dynamical exponents indicate that the ferroelectric domain walls in the epitaxial films are fractal and pinned by a disorder-induced local field.

Domain switching kinetics in disordered ferroelectric thin films

We investigated domain kinetics by measuring the polarization switching behaviors of (111)-preferred polycrystalline Pb(Zr,Ti)O3 films, which are widely used in ferroelectric memories. Their switching behaviors at various electric fields and temperatures could be explained by assuming the Lorentzian distribution of logarithmic domain-switching times. We suggested that the local field variation due to dipole defects at domain pinning sites could explain the Lorentzian distribution.

Polarization switching dynamics governed by the thermodynamic nucleation process in ultrathin ferroelectric films

In most ferroelectrics, the domain nucleation barrier (U*) is thermally insurmountable; this is called "Landauer's paradox." However, we showed that, in ultrathin films, the large depolarization fields could lower U* to a level comparable to thermal energy (k(B)T), resulting in power-law decay of polarization. We empirically found a universal relation between the power-law decay exponent and U*/k(B)T. This relation will provide a practical but fundamental limit for capacitor-type ferroelectric devices, analogous to the superparamagnetic limit for magnetic memory devices.

Polarization relaxation induced by a depolarization field in ultrathin ferroelectric capacitors

Time-dependent polarization relaxation behavior induced by a depolarization field E(d) was investigated on high-quality ultrathin SrRuO3/BaTiO3/SrRuO3 capacitors. The E(d) values were determined experimentally from an applied external field to stop the net polarization relaxation. These values agree with those from the electrostatic calculations, demonstrating that a large E(d) inside the ultrathin ferroelectric layer could cause severe polarization relaxation. For numerous ferroelectric devices of capacitor configuration, this effect will set a stricter size limit than the critical thickness issue.

Primary endobronchial leiomyosarcoma. Diagnosis following expectoration of tumor fragment

A case is presented with spontaneous expectoration of a small piece of solid tissue. Pathologic examination of the expectorated tissue was found to be consistent with leiomyosarcoma. After further work-up, there was no evidence of another primary site of leiomyosarcoma except for the right lower lobe. Right lower lobectomy was performed. The surgical specimen showed a tumor that was histologically identical to the patient's previous expectorated tissue. To the authors' knowledge, this is the first report of partial expectoration of a primary endobronchial leiomyosarcoma.

Endobronchial actinomycosis simulating endobronchial tuberculosis: a case report

We report a case of a 70-year-old woman who presented with mild exertional dyspnea and cough. Fiberoptic bronchoscopic findings revealed an endobronchial polypoid lesion with stenotic bronchus. The lesion was very similar to endobronchial tuberculosis. Histologic examination of the biopsy specimen demonstrated Actinomyces infection. There was a clinical response to intravenous penicillin therapy. Primary endobronchial actinomycosis must be considered in the differential diagnosis of an endobronchial lesion, especially endobronchial tuberculosis in Korea.

Mercury inhalation poisoning and acute lung injury

Acute mercury inhalation poisoning is a rare cause of acute lung injury. It is usually fatal because of progressive pulmonary failure. We experienced a patient with acute respiratory distress syndrome (ARDS) after illicit use of mercury vapor for hemorrhoid treatment; he developed acute chemical pneumonitis following exposure to mercury vapor. Prompt treatment with corticosteroids and penicillamine for acute chemical pneumonitis was instituted; radiologic pulmonary infiltrates disappeared within a week, but late phase neurologic sequelae and pulmonary interstitial fibrosis progressed.