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BACKGROUND: Fatigue is one of the major health conditions induced by excessive stress or abnormal immune function or defective antioxidant systems. Placental extract has been reported to have various effects such as immune modulation and cellular regeneration. Fermented porcine placenta (FPP) is a safe nontoxic material, which is highly valuable as a functional food. The aim of this study was to investigate the anti-fatigue effects of FPP supplementation compared with a placebo product. METHODS: In this double-blind, parallel, randomized, and placebo-controlled trial 84 healthy males and females, aged between 30 and 60 years were randomized to 320 mg of FPP once daily or placebo. The main outcome measures included efficacy of fatigue-inducing treadmill exercise on physical fatigue and fatigue-related parameters based on the questionnaire administered. RESULTS: The IL-1ß mRNA expression and fatigue severity scale were changed significantly after 8 weeks of treatment with fermented porcine placenta compared with placebo (p < 0.05). Cortisol levels were significantly improved in participants younger than 45 years following treatment with FPP compared with placebo. Furthermore, the lactate and myoglobin levels were improved significantly in participants with BMI ≥ 23 kg/m2 (p = 0.045 and p = 0.011, respectively) following treatment with FPP versus placebo. CONCLUSIONS: Our study showed that FPP supplementation significantly ameliorated fatigue-related parameters and subjective symptoms in healthy adults. Therefore, our results indicate that FPP supplementation induced anti-fatigue effect by regulating the inflammatory response.

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Dexmedetomidine, an α2-adrenoceptor agonist, is widely used as a sedative and analgesic agent in a number of clinical applications. However, little is known about the mechanism by which it exerts its analgesic effects on the trigeminal system. Two types of voltage-gated sodium channels, Nav1.7 and Nav1.8, as well as α2-adrenoceptors are expressed in primary sensory neurons of the trigeminal ganglion (TG). Using whole-cell patch-clamp recordings, we investigated the effects of dexmedetomidine on voltage-gated sodium channel currents (INa) via α2-adrenoceptors in dissociated, small-sized TG neurons. Dexmedetomidine caused a concentration-dependent inhibition of INa in small-sized TG neurons. INa inhibition by dexmedetomidine was blocked by yohimbine, a competitive α2-adrenoceptor antagonist. Dexmedetomidine-induced inhibition of INa was mediated by G protein-coupled receptors (GPCRs) as this effect was blocked by intracellular perfusion with the G protein inhibitor GDPß-S. Our results suggest that the INa inhibition in small-sized TG neurons, mediated by the activation of Gi/o protein-coupled α2-adrenoceptors, might contribute to the analgesic effects of dexmedetomidine in the trigeminal system. Therefore, these new findings highlight a potential novel target for analgesic drugs in the orofacial region.

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We evaluated the efficacy of progressive resistance training of the pelvic floor muscle for post-prostatectomy incontinence. In this prospective study, 59 patients who underwent radical prostatectomy were evaluated preoperatively. Continence was sequentially assessed within 2 weeks postoperatively, and an exercise regimen was initiated at 6- and 12-weeks. The primary outcome was continent status and the secondary outcome was changes in muscle strength and endurance after the exercise intervention. Continence was defined as no urine loss in a 1h pad test. A total of 59 patients participated in this study. Six patients dropped out of the study because of non-compliance and orthopedic problems. Of the remaining 53 patients, 31 (58.5%) achieved pad-free continence at 12 weeks postoperatively. The patients were divided into two groups based on their continence status, and no statistically significant difference was observed in age, body mass index, prostate volume, prostate-specific antigen, pathological Gleason score sum, and pathological T stage. Meanwhile, preoperative maximal urethral closure pressure and change in hip extensor muscle strength and endurance during the 12-week exercise program were significantly higher in the continent group. In multivariate analysis, change in hip extensor muscle strength was the only significant parameter predicting achievement of continence status (Odds ratio, 1.039; p = 0.045). The changes in hip extensor muscle strength in the current exercise program was an independent predictor of continence status after radical prostatectomy. A large-scale prospective study on the relationship between extensor muscle strength and urinary incontinence should be explored in future.

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Munc18-1 plays essential dual roles in exocytosis: (i) stabilizing and trafficking the central SNARE protein, syntaxin-1 (i.e. chaperoning function), by its domain-1; and (ii) priming/stimulating exocytosis by its domain-3a. Here, we examine whether or not domain-3a also plays a significant role in the chaperoning of syntaxin-1 and, if so, how these dual functions of domain-3a are regulated. We demonstrate that introduction of quintuple mutations (K332E/K333E/P335A/Q336A/Y337L) in domain-3a of Munc18-1 abolishes its ability to bind syntaxin-1 and fails to rescue the level and trafficking of syntaxin-1 as well as to restore exocytosis in Munc18-1/2 double knockdown cells. By contrast, a quadruple mutant (K332E/K333E/Q336A/Y337L) sparing the Pro-335 residue retains all of these capabilities. A single point mutant of P335A reduces the ability to bind syntaxin-1 and rescue syntaxin-1 levels. Nonetheless, it surprisingly outperforms the wild type in the rescue of exocytosis. However, when additional mutations in the neighboring residues are combined with P335A mutation (K332E/K333E/P335A, P335A/Q336A/Y337L), the ability of the Munc18-1 variants to chaperone syntaxin-1 and to rescue exocytosis is strongly impaired. Our results indicate that residues from Lys-332 to Tyr-337 of domain-3a are intimately tied to the chaperoning function of Munc18-1. We also propose that Pro-335 plays a pivotal role in regulating the balance between the dual functions of domain-3a. The hinged conformation of the α-helix containing Pro-335 promotes the syntaxin-1 chaperoning function, whereas the P335A mutation promotes its priming function by facilitating the α-helix to adopt an extended conformation.

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Aqueous Cu nanoparticles are synthesized using a reducing agent and surface capping molecule which prevents the interparticular agglomeration and surface oxidation. Aqueous conductive nano ink is prepared using the resulting Cu nanoparticles and conductive Cu layers are prepared via a wet coating process. The conductive Cu layers, metalized by annealing at 300 degrees C under vacuum atmosphere, exhibit excellent electrical resistivity, showing values as low as 12 microomega cm. The long-term dispersion stability for three months is monitored through an investigation on the rheological behavior of the conductive nano ink and the resistivity variation of the conductive Cu layer. The adhesion property of the conductive Cu layer is dramatically improved when using a primer-treated polyimide film, whereas the conductive Cu layer completely peels off on a pristine polyimide film. The epoxy-contained primer plays a critical role as an intermediary between the aqueous Cu nano ink and the polyimide film.

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Munc18-1 is believed to prime or stimulate SNARE-mediated membrane fusion/exocytosis through binding to the SNARE complex, in addition to chaperoning its cognate syntaxins. Nevertheless, a Munc18-1 mutant that selectively loses the priming function while retaining the syntaxin chaperoning activity has not been identified. As a consequence, the mechanism that mediates Munc18-1-dependent priming remains unclear. In the course of analyzing the functional outcomes of a variety of point mutations in domain 3a of Munc18-1, we discovered insertion mutants (K332E/K333E with insertions of 5 or 39 residues). These mutants completely lose their ability to rescue secretion whereas they effectively restore syntaxin-1 expression at the plasma membrane as well as dense-core vesicle docking in Munc18-1 and Munc18-2 double-knockdown PC12 cells. The mutants can bind syntaxin-1A in a stoichiometric manner. However, binding to the SNARE complex is impaired compared with the wild type or the hydrophobic pocket mutant (F115E). Our results suggest that the domain 3a of Munc18-1 plays a crucial role in priming of exocytosis, which is independent of its syntaxin-1 chaperoning activity and is downstream of dense-core vesicle docking. We also suggest that the priming mechanism of Munc18-1 involves its domain-3a-dependent interaction with the SNARE complex.

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Munc18-1 plays pleiotropic roles in neurosecretion by acting as 1) a molecular chaperone of syntaxin-1, 2) a mediator of dense-core vesicle docking, and 3) a priming factor for soluble N-ethylmaleimide-sensitive factor attachment protein receptor-mediated membrane fusion. However, how these functions are executed and whether they are correlated remains unclear. Here we analyzed the role of the domain-1 cleft of Munc18-1 by measuring the abilities of various mutants (D34N, D34N/M38V, K46E, E59K, K46E/E59K, K63E, and E66A) to bind and chaperone syntaxin-1 and to restore the docking and secretion of dense-core vesicles in Munc18-1/-2 double-knockdown cells. We identified striking correlations between the abilities of these mutants to bind and chaperone syntaxin-1 with their ability to restore vesicle docking and secretion. These results suggest that the domain-1 cleft of Munc18-1 is essential for binding to syntaxin-1 and thereby critical for its chaperoning, docking, and secretory functions. Our results demonstrate that the effect of the alleged priming mutants (E59K, D34N/M38V) on exocytosis can largely be explained by their reduced syntaxin-1-chaperoning functions. Finally, our data suggest that the intracellular expression and distribution of syntaxin-1 determines the level of dense-core vesicle docking.

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The Vo sector of the vacuolar H(+)-ATPase is a multisubunit complex that forms a proteolipid pore. Among the four isoforms (a1-a4) of subunit Voa, the isoform(s) critical for secretory vesicle acidification have yet to be identified. An independent function of Voa1 in exocytosis has been suggested. Here we investigate the function of Voa isoforms in secretory vesicle acidification and exocytosis by using neurosecretory PC12 cells. Fluorescence-tagged and endogenous Voa1 are primarily localized on secretory vesicles, whereas fluorescence-tagged Voa2 and Voa3 are enriched on the Golgi and early endosomes, respectively. To elucidate the functional roles of Voa1 and Voa2, we engineered PC12 cells in which Voa1, Voa2, or both are stably down-regulated. Our results reveal significant reductions in the acidification and transmitter uptake/storage of dense-core vesicles by knockdown of Voa1 and more dramatically of Voa1/Voa2 but not of Voa2. Overexpressing knockdown-resistant Voa1 suppresses the acidification defect caused by the Voa1/Voa2 knockdown. Unexpectedly, Ca(2+)-dependent peptide secretion is largely unaffected in Voa1 or Voa1/Voa2 knockdown cells. Our data demonstrate that Voa1 and Voa2 cooperatively regulate the acidification and transmitter uptake/storage of dense-core vesicles, whereas they might not be as critical for exocytosis as recently proposed.

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Munc18-1 plays essential roles in neurosecretion by interacting with syntaxin-1 and controlling the formation of the soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) complex. At least three important functions of Munc18-1 have been proposed: (i) molecular chaperone of syntaxin-1 for appropriate localization and expression of syntaxin-1, (ii) priming/stimulation of the SNARE-mediated membrane fusion, and (iii) docking of large dense-core vesicles to the plasma membrane. Similarly, at least two different binding modes have been proposed for the interaction between Munc18-1 and syntaxin-1: (i) binary binding to a 'closed' conformation of syntaxin-1, and (ii) binding to the N-terminal peptide of syntaxin-1, which is thought to enable an interaction with the quaternary SNARE complex and/or further stabilize the binary interaction between Munc18-1 and closed syntaxin-1. Recent structural analyses have identified critical Munc18-1 residues implicated in these different modes of binding. These have recently been tested functionally in rescue experiments using Munc18-1 null neurons, chromaffin cells and Munc18-1/-2 knockdown PC12 cells, allowing remarkable progress to be made in the structural/functional understanding of Munc18-1. In this review, we summarize these recent advances and attempt to propose an updated model of the pleiotropic functions of Munc18-1 in neuroexocytosis.

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Munc18-1 binds to syntaxin-1A via two distinct sites referred to as the "closed" conformation and N terminus binding. The latter has been shown to stimulate soluble N-ethylmaleimide-sensitive factor attachment protein receptor-mediated exocytosis, whereas the former is believed to be inhibitory or dispensable. To precisely define the contributions of each binding mode, we have engineered Munc18-1/-2 double knockdown neurosecretory cells and show that not only syntaxin-1A and -1B but also syntaxin-2 and -3 are significantly reduced as a result of Munc18-1 and -2 knockdown. Syntaxin-1 was mislocalized and the regulated secretion was abolished. We next examined the abilities of Munc18-1 mutants to rescue the defective phenotypes. Mutation (K46E/E59K) of Munc18-1 that selectively prevents binding to closed syntaxin-1 was unable to restore syntaxin-1 expression, localization, or secretion. In contrast, mutations (F115E/E132A) of Munc18-1 that selectively impair binding to the syntaxin-1 N terminus could still rescue the defective phenotypes. Our results indicate that Munc18-1 and -2 act in concert to support the expression of a broad range of syntaxins and to deliver syntaxin-1 to the plasma membrane. Our studies also indicate that the binding to the closed conformation of syntaxin is essential for Munc18-1 stimulatory action, whereas the binding to syntaxin N terminus plays a more limited role in neurosecretory cells.

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Integrated optical devices have been increasingly interested in biosensor applications including environmental pollution, biological process and medical diagnostics. Integrated optics allows high-detection sensitivity to be achieved using optical transduction techniques in a microfluidic format. Among different transduction techniques, a Mach-Zehnder interferometer (MZI) has advantage of its inherent high sensitivity and accuracy. The evanescent wave of an optical waveguide interacts with an adjacent layer, and this can be the basis of the recognition of biomolecules. In recent years, silicon dielectrics as potential materials have been attracted in an integrated optics. The refractive index of these silicon-based materials can be easily adjusted continuously over a wide range between 1.45 (SiO2) and 1.97 (SiO). This comes to be very attractive in terms of design and fabrication of single-mode waveguides. In this article, we tried to realize the Mach-Zehnder interferometer sensor based on silicon oxides, and the refractive index of the oxides was controlled by the oxygen concentration to achieve the single-mode behavior of a total internal reflection (TIR) waveguide. We have performed to verify the feasibility of the MZI sensor for the direct detection of immunoreactions.