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Neuronal activity in the paraventricular nucleus (PVN) is known to be elevated in rats with heart failure. However, the type of neurons involved and the underlying synaptic mechanisms remain unknown. Here we examined spontaneous firing activity and synaptic currents in presympathetic PVN neurons in rats with myocardial infarction (MI), using slice patch clamp combined with the retrograde labeling technique. In PVN neurons projecting to the rostral ventrolateral medulla (PVN-RVLM), MI induced a significant increase in basal firing rate (1.79 to 3.02 Hz, P < 0.05) and a reduction in the frequency of spontaneous (P < 0.05) and miniature (P < 0.01) inhibitory postsynaptic currents (IPSCs). In addition, MI induced an increase in the paired-pulse ratio of evoked IPSCs (P < 0.05). Bicuculline, a GABAA receptor antagonist, increased the firing rate of PVN-RVLM neurons in sham-operated (1.21 to 2.74 Hz, P < 0.05) but not MI (P > 0.05) rats. In contrast, in PVN neurons projecting to the intermediolateral horn of the spinal cord (PVN-IML), MI did not induce any significant changes in the basal firing rate and the properties of spontaneous and miniature IPSCs. The properties of spontaneous excitatory postsynaptic currents (EPSCs) were not altered in either neuron group. In conclusion, our results indicate that MI induces an elevation of firing activity in PVN-RVLM but not in PVN-IML neurons and that the elevated firing rate is largely due to a decrease in GABA release. These results provide evidence for a novel target-selective synaptic plasticity in the PVN that is associated with the sympathetic hyperactivity commonly seen in heart failure. [ABSTRACT FROM AUTHOR]

Gonadotropin-releasing hormone (GnRH) neurons release GnRH in a pulsatile manner to control fertility in all mammals. The mechanisms underlying burst firing in GnRH neurons, thought to contribute to pulsatile GnRH release, are not yet understood. Using minimally invasive, dual electrical-calcium recordings in acute brain slices from GnRH-Pericam transgenic mice, we find that the soma/proximal dendrites of GnRH neurons exhibit long-duration (∼10 s) calcium transients that are perfectly synchronized with their burst firing. These transients were found to be generated by calcium entry through voltage-dependent L-type calcium channels that was amplified by inositol-1,4,5-trisphosphate receptor-dependent store mechanisms. Perforated-patch current- and voltage-clamp electrophysiology coupled with mathematical modeling approaches revealed that these broad calcium transients act to control two slow afterhyperpolarization currents (sIAHP) in GnRH neurons: a quick-activating apamin-sensitive sIAHP that regulates both intraburst and interburst dynamics, and a slow-onset UCL2077-sensitive sIAHP that regulates only interburst dynamics. These observations highlight a unique interplay between electrical activity, calcium dynamics, and multiple calcium-regulated sIAHPs critical for shaping GnRH neuron burst firing. [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is a chronic inflammatory skin disease that commonly begins in childhood. K6PC-9p ( N-(Ethyl dihydrogenphosphate)-2-hexyl-3-oxo-decanamide) is a synthetic ceramide derivative of PC-9S ( N-Ethanol-2-mirystyl-3-oxo-staramide), which was known to be effective in atopic patients. In this study, we examined the effect of topical application of K6PC-9p on skin inflammation and AD-like skin lesions in mouse models. K6PC-9p dose-dependently inhibited phorbol ester-induced increase in ear thickness in BALB/c mice. Moreover, topical application of K6PC-9p suppressed dust mite extract-induced AD-like skin lesions in NC/Nga mice. Histopathological analysis revealed that both ear swelling and leucocyte infiltration were suppressed by K6PC-9p treatment. K6PC-9p also suppressed IL-4 and TNF-α expression in the ears and mast cell infiltration into the ears in NC/Nga mice. Further study demonstrated that K6PC-9p inhibited ConA-induced IL-4 secretion and LPS-induced macrophage activation. Taken together, our results showed that topical application of K6PC-9p exerts beneficial effects in animal model of skin inflammation and AD, suggesting that K6PC-9p might be a promising topical agent for the treatment of inflammatory skin diseases. [ABSTRACT FROM AUTHOR]

Enormous amounts of oyster shell waste have been illegally disposed of at oyster farm sites along the southern coast of Korea. In this study to evaluate the possibility of recycling this waste for use as a construction material, the mechanical characteristics of pulverized oyster shell were investigated in terms of its potential utilization as a substitute for the aggregates used in mortar. The unconfined compressive strengths of various soil mortar specimens, with varying blending ratios of cement, water and oyster shell, were evaluated by performing unconfined compression tests, and the results were compared with the strengths of normal cement mortar made with sand. In addition, the effect of organic chemicals on the hardening of concrete was evaluated by preparing ethyl-benzene-mixed mortar specimens. The long-term strength improvement resulting from the addition of fly ash was also examined by performing unconfined compression tests on specimens with fly-ash content. There was no significant reduction in the compressive strength of the mortars containing small oyster shell particles instead of sand. From these test data, the possible application of oyster shells in construction materials could be verified, and the change in the strength parameters according to the presence of organic compounds was also evaluated. [ABSTRACT FROM AUTHOR]

Purpose. DB75 [2,5-bis(4-amidinophenyl)furan] is a promising antimicrobial agent although it has poor oral potency. In contrast, its novel prodrug, 2,5-bis(4-amidinophenyl)furan-bis-O-methylamidoxime (DB289), has excellent oral potency. The mechanisms of transport of DB289 and DB75 across intestinal epithelium have been investigated in these studies to understand differences in their oral potency. Methods. Caco-2 cell monolayers were used as an in vitro model to examine the mechanisms of transport of DB289 and DB75. Samples collected from the transport studies were quantified using highperformance liquid chromatography with ultraviolet and fluorescence detection. Results. A low permeability coefficient (3.8 × 10[sup -7] cm/s for transport in apical [AP] to basolateral [BL] direction) and high sensitivity to extracellular Ca[sup 2+] suggest that AP to BL transport of DB75 across Caco-2 cell monolayers occurs predominantly via a paracellular route. DB289 has an 85-fold higher transport rate (322.0 × 10[sup -7] cm/s for transport in the AP to BL direction) across Caco-2 monolayers than that of DB75. This, with its insensitivity to extracellular Ca[sup 2+] indicates that AP to BL transport of DB289 across Caco-2 cell monolayers occurs predominantly via a transcellular route. Conclusions. DB75 is transported across Caco-2 cell monolayers predominantly via paracellular pathways, whereas the prodrug DB289 is transported via transcellular pathways. This could account for the much higher oral activity of DB289 over DB75. [ABSTRACT FROM AUTHOR]

Focuses on the structure of Chamois component-based knowledge engineering for electronic commerce application. Development of electronic-payment-system; Provision of application programming interface; Considerations in the delivery of multimedia traffic. INSETS: Metadata Management.;Testing Components with Fault Injection and Mutation Analysis..

Background: The electrophysiologic and antiarrhythmic effects of a new class III antiarrhythmic drug (KCB-328), a delayed rectifier potassium current (IKr) blocker with minimal reverse use-dependent effect on atrial repolarization, were evaluated in the canine night atrial crush-injury model of atrial flutter (AFL).Methods: Ten anesthetized, open-chest dogs, were studied after right atrial crush-injury. Atrial effective refractory period (ERP), conduction velocity (CV), wavelength, and dispersion of refractoriness were determined during programmed stimulation (S1S2 at S1S1 = 200, 300, 400, and 500 msec) at four sites via a mapping plaque sutured on the right atrial free wall. Right and left ventricular ERP were similarly measured at single sites. Electrophysiological parameters were determined at baseline and following sequential cumulative doses of KCB-328 (10, 30, 100, and 300 microg/kg).Results: Sustained AFL was inducible in 7/10 dogs by rapid pacing following baseline electrophysiologic measurements. KCB-328 significantly prolonged sinus cycle length, but had no effect on PR interval, and prolonged QTc only at the highest dose level. KCB-328 significantly prolonged atrial ERP and wavelength and ventricular ERP, and significantly reduced dispersion of atrial refractoriness. KCB-328 significantly prolonged AFL cycle length, and increasing doses progressively terminated sustained AFL and prevented its reinduction by pacing. No adverse hemodynamic or ventricular proarrhythmic effects were observed.Conclusions: The electrophysiologic profile of KCB-328 in this canine model of AFL, particularly its lack of reverse use-dependent effect on atrial refractoriness, suggests that it may have significant antiarrhythmic potential in treatment of atrial arrhythmias. [ABSTRACT FROM AUTHOR]

Treatment of Staphylococcus aureus infections is complicated by the development of antibiotic tolerance, a consequence of the ability of S. aureus to enter into a nongrowing, dormant state in which the organisms are referred to as persisters. We report that the clinically approved anthelmintic agent bithionol kills methicillinresistant S. aureus (MRSA) persister cells, which correlates with its ability to disrupt the integrity of Gram-positive bacterial membranes. Critically, bithionol exhibits significant selectivity for bacterial compared with mammalian cell membranes. All-atom molecular dynamics (MD) simulations demonstrate that the selectivity of bithionol for bacterial membranes correlates with its ability to penetrate and embed in bacterial-mimic lipid bilayers, but not in cholesterol-rich mammalian-mimic lipid bilayers. In addition to causing rapid membrane permeabilization, the insertion of bithionol increases membrane fluidity. By using bithionol and nTZDpa (another membraneactive antimicrobial agent), as well as analogs of these compounds, we show that the activity of membrane-active compounds against MRSA persisters positively correlates with their ability to increase membrane fluidity, thereby establishing an accurate biophysical indicator for estimating antipersister potency. Finally, we demonstrate that, in combination with gentamicin, bithionol effectively reduces bacterial burdens in a mouse model of chronic deep-seated MRSA infection. This work highlights the potential repurposing of bithionol as an antipersister therapeutic agent. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV), the causative agent of hepatitis E, is an important but incompletely understood pathogen causing high mortality during pregnancy and leading to chronic hepatitis in immunocompromised individuals. The underlying mechanisms leading to hepatic damage remain unknown; however, the humoral immune response is implicated. In this study, immunoglobulin (Ig) heavy chain JH-/- knockout gnotobiotic pigs were generated using CRISPR/Cas9 technology to deplete the B-lymphocyte population, resulting in an inability to generate a humoral immune response to genotype 3 HEV infection. Compared to wild-typegnotobiotic piglets, the frequencies of B lymphocytes in the Ig heavy chain JH-/-knockouts were significantly lower, despite similar levels of other innate and adaptive T-lymphocyte cell populations. The dynamic of acute HEV infection was subsequentlydetermined in heavy chain JH-/- knockout and wild-type gnotobiotic pigs. The data showed that wild-type piglets had higher viral RNA loads in feces and seracompared to the JH-/- knockout pigs, suggesting that the Ig heavy chain JH-/-knockout in pigs actually decreased the level of HEV replication. Both HEV-infectedwild-type and JH-/- knockout gnotobiotic piglets developed more pronounced lymphoplasmacytichepatitis and hepatocellular necrosis lesions than other studies with Hepatitis E virus (HEV), the causative agent of hepatitis E, is an importantbut incompletely understood pathogen causing high mortality during pregnancyand leading to chronic hepatitis in immunocompromised individuals. The underlyingmechanisms leading to hepatic damage remain unknown; however, thehumoral immune response is implicated. In this study, immunoglobulin (Ig) heavychain JH-/- knockout gnotobiotic pigs were generated using CRISPR/Cas9 technologyto deplete the B-lymphocyte population, resulting in an inability to generate ahumoral immune response to genotype 3 HEV infection. Compared to wild-typegnotobiotic piglets, the frequencies of B lymphocytes in the Ig heavy chain JH-/-knockouts were significantly lower, despite similar levels of other innate and adaptive T-lymphocyte cell populations. The dynamic of acute HEV infection was subsequentlydetermined in heavy chain JH-/- knockout and wild-type gnotobiotic pigs. The data showed that wild-type piglets had higher viral RNA loads in feces and seracompared to the JH-/- knockout pigs, suggesting that the Ig heavy chain JH-/-knockout in pigs actually decreased the level of HEV replication. Both HEV-infectedwild-type and JH-/- knockout gnotobiotic piglets developed more pronounced lymphoplasmacytichepatitis and hepatocellular necrosis lesions than other studies withconventional pigs. The HEV-infected JH-/- knockout pigs also had significantly enlargedlivers both grossly and as a ratio of liver/body weight compared tophosphate-buffered saline-inoculated groups. This novel gnotobiotic pig model willaid in future studies into HEV pathogenicity, an aspect which has thus far been difficultto reproduce in the available animal model systems. IMPORTANCE According to the World Health Organization, approximately 20 million HEV infections occur annually, resulting in 3.3 million cases of hepatitis E and >44,000 deaths. The lack of an efficient animal model that can mimic the fullspectrumof infection outcomes hinders our ability to delineate the mechanism of HEV pathogenesis. Here, we successfully generated immunoglobulin heavy chain JH-/- knockout gnotobiotic pigs using CRISPR/Cas9 technology, established a novel JH-/- knockout and wild-type gnotobiotic pig model for HEV, and systematically determinedthe dynamic of acute HEV infection in gnotobiotic pigs. It was demonstratedthat knockout of the Ig heavy chain in pigs decreased the level of HEV replication. Infected wild-type and JH-/- knockout gnotobiotic piglets developed more pronounced HEV-specific lesions than other studies using conventional pigs, and theinfected JH-/- knockout pigs had significantly enlarged livers. The availability of thisnovel model will facilitate future studies of HEV pathogenicity. [ABSTRACT FROM AUTHOR]