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Caspase-2 was discovered almost three decades ago. It was one of the first two mammalian homologs of CED-3, the other being interleukin 1β-converting enzyme (ICE/caspase-1). Despite high similarity with CED-3 and its fly and mammalian counterparts (DRONC and caspase-9, respectively), the function of caspase-2 in apoptosis has remained enigmatic. A number of recent studies suggest that caspase-2 plays an important role in the regulation of p53 in response to cellular stress and DNA damage to prevent the proliferation and accumulation of damaged or aberrant cells. Here, we review these recent observations and their implications in caspase-2-mediated cellular death, senescence, and tumor suppression., Cancer: Enzyme stabilizes tumor suppressor protein Under conditions such as DNA damage or mitotic stress, the enzyme caspase-2 plays a vital role in regulating the stability of p53, a tumor suppressor protein. Caspases play multiple roles in cellular homeostasis, inflammation and programmed cell death. Sharad Kumar and colleagues at the Centre for Cancer Biology, UniSA in Adelaide, Australia, review current understanding of caspase-2 and its links with p53. Caspase-2 deficiency leads to defective p53 signaling, suggesting a regulatory link between the two molecules. Recent studies suggest that following DNA damage or cytokinesis failure caspase-2 cleaves MDM2, the p53 ubiquitin ligase, to stabilize p53. This prevents the proliferation of damaged cells, aneuploidy and accumulation of potentially premalignant cells. Reduced caspase-2 levels are associated with enhanced cancer progression in several models. The p53 regulatory function may explains this tumor suppressive activity of caspase-2.

The fabrication of uniform amorphous silicon (a-Si) nanoshell on graphite is recognized as a high energy technique for building block into macroscopic materials. Here in, various thick containing nanoscaled A-Si nanoshells could easily be adjusted by controlling the preparation conditions. In this structure, A-Si nanoshell thickness with up to 24 nm are uniformly coated and supported on anode composite. The resulting AG@a-Si-90min composites (a-Si shell thickness ≈ 15 nm) exhibited better cycle reversibility and stability than among samples. The G@a-Si-90 sample delivered a relatively stable specific capacity of ca. 384 mAh.g-1 at 1.3 A g−1 (1C: 650 mAh.g-1) for 200 cycles. Furthermore, the designed A-Si shell by CVD can also be applied to the study of the synergetic properties of great importance for the large-scale production for batteries and other devices.

Germanium (Ge) is a promising anode material for lithium-ion batteries (LIBs) due to its large theoretical specific capacity (1600 mA h g−1), high Li diffusivity and large intrinsic electrical conductivity. Despite these merits, its large volumetric change during lithiation/delithiation process and relatively high production cost make it difficult to use in commercial batteries. In this paper, we report a facile, easy to scale up, and environmentally friendly method to prepare an amorphous phase GeOx (x

Mitotic catastrophe (MC) is an important oncosuppressive mechanism that serves to eliminate cells that become polyploid or aneuploidy due to aberrant mitosis. Previous studies have demonstrated that the activation and catalytic function of caspase-2 are key steps in MC to trigger apoptosis and/or cell cycle arrest of mitotically defective cells. However, the molecular mechanisms that regulate caspase-2 activation and its function are unclear. Here we identify six new phosphorylation sites in caspase-2 and show that a key mitotic kinase, Aurora B kinase (AURKB), phosphorylates caspase-2 at the highly conserved residue S384. We demonstrate that phosphorylation at S384 blocks caspase-2 catalytic activity and apoptosis function in response to mitotic insults, without affecting caspase-2 dimerisation. Moreover, molecular modelling suggests that phosphorylation at S384 may affect substrate binding by caspase-2. We propose that caspase-2 S384 phosphorylation by AURKB is a key mechanism that controls caspase-2 activation during mitosis.

We investigated the influence of simvastatin, a statin, on the secretion of catecholamines (CA) in rat adrenal glands, and clarified its action mechanism. Simvastatin suppressed acetylcholine (ACh)-evoked CA release in a dose- and time-dependent fashion. In the presence of simvastatin, CA secretion evoked by 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP), angiotensin II, high K+, veratridine, and Bay-K-8644 was time-dependently inhibited. However, in the simultaneous presence of simvastatin and Nω-nitro-L-arginine methyl ester hydrochloride, CA secretion evoked by angiotensin II and DMPP recovered to control levels. Adrenal NO release was increased by simvastatin-treatment. Simvastatin-inhibited CA secretion was not affected by treatment with mevalonate. Pravastatin did not influence ACh-evoked CA secretion, while atorvastatin reduced it. In the simultaneous presence of simvastatin and fimasartan, ACh-induced CA release was markedly reduced compared to that of fimasartan-treatment alone. We present the first evidence that simvastatin reduces adrenal CA secretion induced by stimulation of nicotinic and AT1-receptors. Simvastatin-induced inhibition seems to involve reducing the influx of both Ca2+ and Na+ into adrenochromaffin cells, partly via the elevation of NO production by NO synthase activation, without inhibition of 3-hydroxy-methylglutaryl coenzyme A reductase. Co-administration of simvastatin and fimasartan may be clinically helpful for the treatment of cardiovascular diseases.

A sensitive and highly reproducible cardiac troponin I (cTnI) immunoassay in human serum is a challenging research goal for researchers studying biosensors because cTnI can undergo proteolysis and various modifications in blood. Furthermore, the reproducible detection of cTnI at very low concentrations is also required for diagnosing acute myocardial infarction. Here, we present sensitive and highly reproducible quartz crystal microbalance (QCM) immunosensors for the detection of cTnI in human serum. The unique features of this study are the use of a pair of capture antibodies that bind to different epitopes of cTnI, and the use of a signal amplification technique that enlarged the size of the titanium dioxide nanoparticles using photocatalytic silver staining. Since QCM measures changes in the resonance frequency due to the changes in mass occurring on the sensor surface, it is possible to quantitatively analyze cTnI based on the enormous increase in mass using a sandwich immunoassay and subsequent signal amplification by silver staining. The detection limit of the cTnI immunoassay in human serum without photocatalytic silver staining was 307 pg/ml, but 18 pg/ml in photocatalytic silver staining-mediated signal amplification. Thus, amplifying the signal increased the sensitivity and reproducibility of the cTnI immunoassay in human serum.

Background The Kidney Donor Risk Index (KDRI) scoring system for deceased donors has been widely introduced for postoperative evaluation of graft function. We analyzed the usefulness of the KDRI in deceased donors with acute kidney injury (AKI). Methods Forty-nine recipients from deceased donors with AKI between January 2009 and December 2014 were reviewed retrospectively. Data collected from donor medical records included age, height, weight, hypertension or diabetes history, cause of death, serum creatinine (sCr), and donation after cardiac death. Graft function data including sCr, estimated glomerular filtration rate (eGFR), and acute rejection episodes were monitored for 1 year. Correlations between KDRI score and factors indicating graft function were analyzed. A cutoff value for KDRI score was calculated using a receiver operating characteristic (ROC) curve for significant graft function. Results The mean ages of donors and recipients were 46.81 ± 13.13 and 47.69 ± 11.43, respectively. The mean KDRI score was 1.24 ± 0.40. Univariable analysis of KDRI score and factors indicating graft function indicated that sCr at 6 to 12 months, eGFR at 1 year, and slow graft function (SGF) had statistical significance. The ROC curve of KDRI score for SGF showed an optimal cutoff value of 1.20, with sensitivity of 69.2% and specificity of 69.4% (area under the curve = 0.75) in deceased donors with AKI. Conclusions KDRI score in deceased donors with AKI was correlated with postoperative graft values including eGFR and SGF. KDRI could be used as a predictor for the short-term clinical outcome after kidney transplant from deceased donor with AKI.

Although low serum bicarbonate level is known to be associated with adverse outcomes in patients with chronic kidney injury, it is unclear whether low serum bicarbonate level is associated with the development of acute kidney injury (AKI). The purpose of our study was to determine whether serum bicarbonate levels at admission could be a risk factor for AKI development and mortality in hospitalised patients. We retrospectively enrolled 17,320 adult patients who were admitted to the academic teaching hospital from January 2013 to December 2013. Patients were divided into 2 groups based on the first measurement of serum bicarbonate level at admission. The incidence of AKI was higher in patients with low serum bicarbonate level than in those with normal serum bicarbonate level (8.0% vs. 4.1%). Low serum bicarbonate levels at admission were significantly associated with the development of AKI. In addition, low serum bicarbonate levels also independently predicted the 90-day mortality. Pre-existing low bicarbonate levels and subsequent development of AKI increased in-hospital mortality by 15 times compared with that in patients with normal bicarbonate levels and no AKI. Low serum bicarbonate levels may be associated with the development of AKI and high mortality in hospitalised patients.

When BDNF binds to its receptors, TrkB and p75NTR, the BDNF-receptor complex is endocytosed and trafficked to the cell body for downstream signal transduction, which plays a critical role in neuronal functions. Huntingtin-associated protein 1 (HAP1) is involved in trafficking of vesicles intracellularly and also interacts with several membrane proteins including TrkB. Although it has been known that HAP1 has functions in vesicular trafficking and receptor stabilisation, it is not yet established whether HAP1 has a role in BDNF and its receptor endocytosis. In the present study, we found that HAP1 is in an interacting complex with p75NTR,TrkB and BDNF, especially newly endocytosed BDNF.BDNF and TrkB internalisation is abolished in HAP1 knock-out (KO) cortical neurons. TrkB downstream signalling pathways such as ERK, Akt and PLCγ-1 are also impaired in HAP1 KO cortical neurons upon BDNF stimulation. Proliferation of cerebellar granule cells is also impaired in cell culture and cerebellum of HAP1 KO mice. Our findings suggest that HAP1 may play a key role in BDNF and its receptor endocytosis and may promote neuronal survival and proliferation. Refereed/Peer-reviewed

Background Euglycaemic ketoacidosis has been reported after sodium–glucose cotransporter 2 (SGLT2) inhibitor treatment. However, the degree of ketonaemia and its metabolic effects have not been well investigated. Our study examined the degree of ketonaemia induced by SGLT2 inhibition and its association with metabolic profiles in type 2 diabetes mellitus (T2DM). Methods Biochemical parameters, including insulin, glucagon, free fatty acid (FFA), β-hydroxybutyrate (BHB) and acetoacetate (ACA) levels, were measured in 119 T2DM patients after dapagliflozin treatment for>3 months, and compared with a matched control group. Results Levels of total ketones, BHB and ACA were significantly higher in the dapagliflozin group than in the control group: 283.7±311.0 vs 119.8±143.8μmol/L; 188.3±226.6 vs 78.0±106.7μmol/L; and 94.1±91.3 vs 41.8±39.1μmol/L, respectively (all P 440μmol/L) in 13 (10.9%) patients who had no relevant symptoms. BHB level after dapagliflozin treatment correlated positively with HbA 1c ( r =0.280), FFA levels ( r =0.596) and QUICKI ( r =0.238), and negatively with BMI ( r =−0.222), insulin-to-glucagon ratio ( r =−0.199) and HOMA-IR ( r =−0.205; all P Conclusion Ketone levels were higher in T2DM patients treated with dapagliflozin than in controls, but with no clinical symptoms or signs of ketonaemia. Low-grade ketonaemia after dapagliflozin treatment may also be associated with improved insulin sensitivity.

Background: Recent observational studies have shown that in chronic kidney disease (CKD) patients, a significantly smaller percentage of patients with an episode of acute kidney injury (AKI) have full recovery of renal function compared to those without CKD. However, precise mechanisms involved in the incomplete repair after AKI with preexisting CKD have not been completely ascertained. Here, we assessed the impact of preexisting CKD on the severity and recovery of AKI in a mouse model of 5/6 nephrectomy. Methods: Male CD-1 mice underwent 5/6 nephrectomy (Nx). Six weeks post surgery, ischemia reperfusion injury (IRI) or a sham operation was performed and functional, histological, and various molecular parameters were compared between them. Results: Serum creatinine level on day 1 after IRI was comparable between control and Nx mice. However, serum creatinine remained significantly higher throughout the recovery phase in Nx mice compared to control mice. mRNA and protein expression of the cell cycle regulatory proteins were persistently elevated in Nx mice and this was associated with significantly increased levels of the G1 cell cycle arrest markers. Treatment with a p53 inhibitor following IRI resulted in not only decreased expression of G1 arrest markers but also decreased fibrosis, suggesting that prolonged epithelial G1 cell cycle arrest might be partially responsible for impaired recovery from superimposed AKI on CKD. Conclusion: Taken together, reduced nephron mass have a negative effect on the repair process that is partially mediated by the disruption of the cell cycle regulation.

Background Recently, urinary tissue inhibitor of metalloproteinase–2 (TIMP-2) and insulin-like growth factor–7 (IGFBP-7), markers for G1 cell cycle arrest, have been identified and validated in predicting the development of acute kidney injury in critically ill patients. It is unknown, however, whether these two biomarkers could predict the development of delayed graft function (DGF) after kidney transplantation (KT). Methods This is a single-center, prospective, observational study. We enrolled 74 patients who underwent KT between August 2013 and December 2016. Urine sample were collected immediately after the operation. The primary outcome was development of DGF as defined by need for dialysis of more than 1 session within 7 days of KT. Results Twenty-three patients (31%) were diagnosed with DGF. In univariate analysis, kidneys from expanded criteria donors, higher donor serum creatinine, lower donor estimated glomerular filtration rate, antithymoglobulin exposure, neutrophil gelatinase associated lipocalin, and urinary [TIMP-2]·[IGFBP7] were significantly different between early graft function and DGF. However, in multivariate analysis adjusting other factors, deceased donor and urinary [TIMP-2]·[IGFBP7] at 0 hours post-transplantation could predict the development of DGF. The receiver operating characteristic curve for prediction of DGF showed an area under the curve of 0.867 (sensitivity 0.86, specificity 0.71) for a cutoff value of 1.39. Conclusions Our results indicate that urine [TIMP-2]·[IGFBP7] immediately after transplantation could be an early, predictive biomarker of DGF in kidney transplantation.

Background: The present study was the first attempt to explore the characteristics of ginsenoside-Rg3 (Rg3) on release of catecholamines (CA) in the perfused rat adrenal medullae and also to verify the underlying action mechanism. Materials and Methods: The adrenal medulla was separated by some modification of the previous method and perfused with Krebs solution. CA was assayed directly by the fluorometry. Results: Rg3 reduced acetylcholine (ACh)-produced CA release in a dose- and time-dependent manner. Rg3 time-dependently depressed CA release produced by 3-(m-chloro-phenyl-carbamoyl-oxy)-2-butynyltrimethyl ammonium chloride (McN-A-343), 1,1-dimethyl-4-phenyl piperazinium iodide, and angiotensin II. In the presence of Rg3, the CA release produced by high K+, veratridine, cyclopiazonic acid, and methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4- (2-trifluoromethyl-phenyl)-pyridine-5-carboxylate (Bay-K-8644) was also markedly suppressed. However, during the simultaneous perfusion of Rg3 and Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME), the release of CA produced by ACh, angiotensin II, Bay-K-8644, and veratridine was restored closely to the level of each control, in contrast to that of Rg3-treatment alone. The nitric oxide (NO) release was significantly elevated by Rg3-treatment. Furthermore, in the coexistence of Rg3 and fimasartan, ACh-produced CA release was more significantly reduced as compared to that of fimasartan-treatment alone. Conclusions: We present the first evidence that Rg3 markedly depresses the CA secretion produced by activation of neuronal cholinergic and angiotensinergic receptors. Rg3-produced inhibition appears to be evoked not only by blocking the inflow of Na+ and Ca2+ into adrenomedullary cells but also by preventing the Ca2+ release from intracellular storage, partly through enhancement of NO release by NO synthase activation. Coadministration of Rg3 and fimasartan may be clinically beneficial for the treatment of cardiovascular diseases. Abbreviations used: Rg3: Ginsenoside-Rg3; VDCC: L-type voltage-dependent Ca2+ channels; Bay–K-8644: Methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethyl-phenyl)-pyridine-5-carboxylate; ACh: Acetylcholine; McN-A-343: 3-(m-chloro-phenyl-carbamoyl-oxy)-2-butynyltrimethyl ammonium; DMPP: 1.1-dimethyl-4-phenyl piperazinium; NO: Nitric oxide; L-NAME: Nω-nitro-l-arginine methyl ester; nNOS: Neuronal NO synthase.

Sortilin, a Golgi sorting protein and a member of the VPS10P family, is the co-receptor for proneurotrophins, regulates protein trafficking, targets proteins to lysosomes, and regulates low density lipoprotein metabolism. The aim of this study was to investigate the expression and regulation of sortilin in Alzheimer's disease (AD). A significantly increased level of sortilin was found in human AD brain and in the brains of 6-month-old swedish-amyloid precursor protein/PS1dE9 transgenic mice. Aβ42 enhanced the protein and mRNA expression levels of sortilin in a dose- and time-dependent manner in SH-SY5Y cells, but had no effect on sorLA. In addition, proBDNF also significantly increased the protein and mRNA expression of sortilin in these cells. The recombinant extracellular domain of p75NTR (P75ECD-FC), or the antibody against the extracellular domain of p75NTR, blocked the up-regulation of sortilin induced by Amyloid-β protein (Aβ), suggesting that Aβ42 increased the expression level of sortilin and mRNA in SH-SY5Y via the p75NTR receptor. Inhibition of ROCK, but not Jun N-terminal kinase, suppressed constitutive and Aβ42-induced expression of sortilin. In conclusion, this study shows that sortilin expression is increased in the AD brain in human and mice and that Aβ42 oligomer increases sortilin gene and protein expression through p75NTR and RhoA signaling pathways, suggesting a potential physiological interaction of Aβ42 and sortilin in Alzheimer's disease. Sortilin is the co-receptor of p75NTR which signals the cell death induced by Aβ and proneurotrophins. We found that sortilin is increased in the AD brain and up-regulated by Aβ and pro-brain-derived neurotrophic factor (proBDNF). Aβ-induced upregulation of sortilin is mediated by p75NTR and the down-streaming RhoA-ROCK signaling pathway. The Aβ/Sortilinp/75NTR signaling may play a role in the pathogenesis of AD. Refereed/Peer-reviewed

The aim of this study was to determine whether fimasartan, a newly developed AT(1) receptor blocker, can affect the CA release in the isolated perfused model of the adrenal medulla of spontaneously hypertensive rats (SHRs). Fimasartan (5~50 µM) perfused into an adrenal vein for 90 min produced dose- and time-dependently inhibited the CA secretory responses evoked by ACh (5.32 mM), high K(+) (56 mM, a direct membrane depolarizer), DMPP (100 µM) and McN-A-343 (100 µM). Fimasartan failed to affect basal CA output. Furthermore, in adrenal glands loaded with fimasartan (15 µM), the CA secretory responses evoked by Bay-K-8644 (10 µM, an activator of L-type Ca(2+) channels), cyclopiazonic acid (10 µM, an inhibitor of cytoplasmic Ca(2+)-ATPase), and veratridine (100 µM, an activator of Na(+) channels) as well as by angiotensin II (Ang II, 100 nM), were markedly inhibited. In simultaneous presence of fimasartan (15 µM) and L-NAME (30 µM, an inhibitor of NO synthase), the CA secretory responses evoked by ACh, high K(+), DMPP, Ang II, Bay-K-8644, and veratridine was not affected in comparison of data obtained from treatment with fimasartan (15 µM) alone. Also there was no difference in NO release between before and after treatment with fimasartan (15 µM). Collectively, these experimental results suggest that fimasartan inhibits the CA secretion evoked by Ang II, and cholinergic stimulation (both nicotininc and muscarinic receptors) as well as by membrane depolarization from the rat adrenal medulla. It seems that this inhibitory effect of fimasartan may be mediated by blocking the influx of both Na(+) and Ca(2+) through their ion channels into the rat adrenomedullary chromaffin cells as well as by inhibiting the Ca(2+) release from the cytoplasmic calcium store, which is relevant to AT(1) receptor blockade without NO release.

Amyloid precursor protein (APP) is involved in the pathogenesis of Alzheimer's disease. It is axonally transported, endocytosed and sorted to different cellular compartments where amyloid beta (Aβ) is produced. However, the mechanism of APP trafficking remains unclear. We present evidence that huntingtin associated protein 1 (HAP1) may reduce Aβ production by regulating APP trafficking to the non-amyloidogenic pathway. HAP1 and APP are highly colocalized in a number of brain regions, with similar distribution patterns in both mouse and human brains. They are associated with each other, the interacting site is the 371-599 of HAP1. APP is more retained in cis-Golgi, trans-Golgi complex, early endosome and ER-Golgi intermediate compartment in HAP1-/- neurons. HAP1 deletion significantly alters APP endocytosis and reduces the re-insertion of APP into the cytoplasmic membrane. Amyloid precursor protein-YFP(APP-YFP) vesicles in HAP1-/- neurons reveal a decreased trafficking rate and an increased number of motionless vesicles. Knock-down of HAP1 protein in cultured cortical neurons of Alzheimer's disease mouse model increases Aβ levels. Our data suggest that HAP1 regulates APP subcellular trafficking to the non-amyloidogenic pathway and may negatively regulate Aβ production in neurons.

In this study, we investigated the changes of electrical resistance of indium-tin-oxide (ITO) film. To find the relationship between the physical properties of base substrate materials and mechanical stability, the mechanical and electrical stability of various ITO coated polymer substrates have been investigated. From intensive study on the mechanical and electrical stability of ITO coated polymer substrates, it was found that the physical property of base polymer material such as Young's modulus had a great influence of mechanical and electrical stability of polymer substrate under continuous bending stress condition and polymer substrate with lower Young's modulus showed better stability against compressive and tensile stresses.

The purpose of the present study was to investigate whether polyphenol-rich fraction extracted from fruit wine of Rubus coreanum M (PCRC) can affect the contractility of the thoacic aortic strips isolated from spontaneously hypertensive rats (SHRs), and to clarify its mechanism of action. PCRC (200-800 μg/ml) concentration-depenedently blocked phenylephrine (10 μM)-induced contractile responses of the isolated aortic strips of SHRs. PCRC (400 μg/ml), added in to bath medium, also depressed the contractile active tension evoked by both phenylephrine (3 and 10 μM) and high potassium (25 and 56 mM). In the simultaneous presence of PCRC (400 μg/ml) and L-NAME (a selective inhibitor of NO synthase, 300 μM), the contractile responses evoked by phenylephrine and high K + were recovered to considerable level of the corresponding control contractility compared with those effects of PCRC-treatment alone. However, in the simultaneous presence of indomethacin (10 μM, a selective cyclooxygenase inhibitor) and PCRC (400 μg/ml), they were not affected. In the endothelium-denuded aortic strips by CHAPS-treatment, PCRC did not affect the contractile responses induced by phenylephrine or high potassium. Interestingly, PCRC (1.0, 3.0 and 10.0 mg/ kg/30 min, i.v., respectively) dose-dependently suppressed norepiphrine-induced vasopressor responses in anesthetized SHRs. Collectively, we concluded that PCRC causes vasorelaxation in the thoracic aortic strips with intact endothelium of SHRs at least partly by the increased NO production through the activation of NO synthase of vascular endothelium, but not through the activation of cyclooxygenase.These results suggest that PCRC might be helpful to prevent or alleviate cardiovascular diseases, including hypertension.

There seems to be some controversy about the effect of total ginseng saponin (TGS) on the secretion of catecholamines (CA) from the adrenal gland. Therefore, the present study aimed to determine whether TGS can affect the CA release in the perfused model of the adrenal medulla isolated from spontaneously hypertensive rats (SHRs). TGS (15-150 μg/mL), perfused into an adrenal vein for 90 min, inhibited the CA secretory responses evoked by acetylcholine (ACh, 5.32 mM) and high K(+) (56 mM, a direct membrane depolarizer) in a dose- and time-dependent fashion. TGS (50 μg/mL) also time-dependently inhibited the CA secretion evoked by 1.1-dimethyl-4 -phenyl piperazinium iodide (DMPP; 100 μM, a selective neuronal nicotinic receptor agonist) and McN-A-343 (100 μM, a selective muscarinic M1 receptor agonist). TGS itself did not affect basal CA secretion (data not shown). Also, in the presence of TGS (50 μg/mL), the secretory responses of CA evoked by veratridine (a selective Na(+) channel activator (50 μM), Bay-K-8644 (an L-type dihydropyridine Ca(2+) channel activator, 10 μM), and cyclopiazonic acid (a cytoplasmic Ca(2+)-ATPase inhibitor, 10 μM) were significantly reduced, respectively. Interestingly, in the simultaneous presence of TGS (50 μg/mL) and Nω-nitro-L-arginine methyl ester hydrochloride [an inhibitor of nitric oxide (NO) synthase, 30 μM], the inhibitory responses of TGS on the CA secretion evoked by ACh, high K(+), DMPP, McN-A-343, Bay-K-8644, cyclopiazonic acid, and veratridine were considerably recovered to the extent of the corresponding control secretion compared with the inhibitory effect of TGS-treatment alone. Practically, the level of NO released from adrenal medulla after the treatment of TGS (150 μg/mL) was greatly elevated compared to the corresponding basal released level. Taken together, these results demonstrate that TGS inhibits the CA secretory responses evoked by stimulation of cholinergic (both muscarinic and nicotinic) receptors as well as by direct membrane-depolarization from the isolated perfused adrenal medulla of the SHRs. It seems that this inhibitory effect of TGS is mediated by inhibiting both the influx of Ca(2+) and Na(+) into the adrenomedullary chromaffin cells and also by suppressing the release of Ca(2+) from the cytoplasmic calcium store, at least partly through the increased NO production due to the activation of nitric oxide synthase, which is relevant to neuronal nicotinic receptor blockade, without the enhancement effect on the CA release. Based on these effects, it is also thought that there are some species differences in the adrenomedullary CA secretion between the rabbit and SHR.

A gene (m1ft) encoding levansucrase from Leuconostoc mesenteroides has been previously cloned in Escherichia coli. Presently, m1ft was cloned and secretively expressed in Pichia pastoris. Methanol induction of recombinant M1FT resulted in the production of active levansucrase (PM1FT). PM1FT-5 was expressed as an active form, but the protein accumulated mainly inside the cells, representing about 5% of total cell proteins. M1FT was secreted into the culture supernatant with a maximum yield of 14,400 U/L using fed-batch fermentations. P. pastoris-derived M1FT displayed catalytic activities comparable to those of the E. coli-derived M1FT. PM1FT was glycosylated at its 2 potential N-glycosylation sites.

A self-assembled peptide hydrogel consisting of Fmoc-diphenylalanine has been employed as a biosensing platform through the encapsulation of enzyme bioreceptors (e.g., glucose oxidase or horseradish peroxidase) and fluorescent reporters (e.g., CdTe and CdSe quantum dots). Enzymes and quantum dots (QDs) were physically immobilized within the hydrogel matrix in situ in a single step by simply mixing aqueous solution containing QDs and enzymes with monomeric peptide (Fmoc-diphenylalanine) solution. By using atomic force microscopy and scanning transmission electron microscopy, we observed that the self-assembled peptide hydrogel had a three-dimensional network of nanofibers (with a diameter of approximately 70-90 nm) that physically hybridized with QDs and encapsulated enzyme bioreceptors with a minimal leakage. We successfully applied the peptide hydrogel to the detection of analytes such as glucose and toxic phenolic compounds by using a photoluminescence quenching of the hybridized QDs. The Michaelis-Menten constant (K(M)) of the photoluminescent peptide hydrogel was found to be 3.12 mM (GOx for glucose) and 0.82 mM (HRP for hydroquinone), respectively, which were much lower than those of conventional gel materials. These results suggest that the peptide hydrogel is an alternative optical biosensing platform with practical advantages such as simple fabrication via self-assembly, efficient diffusion of target analytes, and high encapsulation efficiencies for fluorescent reporters and bioreceptors.

To compare the outcomes of treatment with intravitreal bevacizumab alone (BEVA group) or in combination with photodynamic therapy (PDT) (COMB group), in patients aged at least 50 years with neovascular maculopathy.Forty-one patients with neovascular age-related macular degeneration (AMD) (n = 31) or polypoidal choroidal vasculopathy (PCV) (n = 10) were randomized to either the BEVA group (n = 18) or the COMB group (n = 23). A total of three intravitreal bevacizumab injections (1.25 mg/0.05 ml) were given at 6-week intervals. In the COMB group, PDT was included near the time of one injection. Patients underwent best-corrected visual acuity (BCVA) measurement and optical coherence tomography (OCT) at every visit. Fluorescein angiography and indocyanine green angiography were repeated every 3 months.Overall BCVA (p = 0.001) and central foveal thickness (CFT) (p0.001) measured by OCT improved significantly at 12 months, and there was no between-group difference in BCVA or CFT between the BEVA and COMB groups. Whereas AMD patients showed significant improvement in BCVA (p = 0.001) and CFT (p = 0.004), PCV patients failed to improve. The effect of bevacizumab alone on neovascular AMD was similar to that of combination therapy, when measured by both BCVA and CFT. The total number of bevacizumab injections was not reduced when PDT was given, either among all patients or in a subgroup of naïve patients (p0.05). No serious complication was noted.The results of our 12-month prospective study indicate that intravitreal bevacizumab alone has similar efficacy and safety to bevacizumab plus PDT for treatment of patients with neovascular AMD, even treatment-naïve patients. The addition of PDT did not assist in reducing the required total number of bevacizumab injections.

The purpose of the present study was to examine the effect of dihydrexidine, a full receptor agonist, on the secretion of catecholamines (CA) from the perfused model of the rat adrenal gland, and to establish its mechanism of action. Dihydrexidine (10-100 ), perfused into an adrenal vein for 60 min, relatively produced dose- and time-dependent inhibition in the CA secretory responses evoked by ACh (5.32 mM), high (56 mM), DMPP (100 ) and McN-A-343 (100 ). Dihydrexidine itself did fail to affect basal CA output. Also, in adrenal glands loaded with dihydrexidine (30 ), the CA secretory responses evoked by Bay-K-8644 (10 ), an activator of L-type channels, cyclopiazonic acid (10 ), an inhibitor of cytoplasmic -ATPase, and veratridine, an activator of voltage-dependent channels (10 ), were also markedly inhibited, respectively. However, in the simultaneous presence of dihydrexidine (30 ) and R (+)-SCH23390 (a selective antagonist of receptor, 3 ), the CA secretory responses evoked by ACh, high K+, DMPP, McN-A-343, Bay-K-8644, cyclopiazonic acid and veratridine were considerably recovered to the extent of the corresponding control secretion compared with the inhibitory responses by dihydrexidinetreatment alone. In conclusion, these experimental results suggest that dihydrexidine significantly inhibits the CA secretion evoked by cholinergic stimulation (both nicotinic and muscarinic receptors) and membrane depolarization from the rat adrenal medulla. It seems that this inhibitory effect of dihydrexidine may be mediated by inhibiting influx of both and into the cytoplasm as well as by suppression of release from cytoplasmic calcium store through activation of dopaminergic receptors located on the rat adrenomedullary chromaffin cells.

The aim of the present study was to investigate the effect of glibenclamide, a hypoglycemic sulfonylurea, which selectively blocks ATP-sensitive K channels, on secretion of catecholamines (CA) evoked by cholinergic stimulation and membrane depolarization from the isolated perfused rat adrenal glands. The perfusion of glibenclamide (1.0 mM) into an adrenal vein for 90 min produced time-dependently enhanced the CA secretory responses evoked by ACh (5.32 mM), high K (a direct membrane depolarizer, 56 mM), DMPP (a selective neuronal nicotinic receptor agonist, 100 M for 2 min), McN-A-343 (a selective muscarinic M1 receptor agonist, 100 M for 2 min), Bay-K-8644 (an activator of L-type dihydropyridine Ca channels, 10 M for 4 min) and cyclopiazonic acid (an activator of cytoplasmic Ca-ATPase, 10 M for 4 min). In adrenal glands simultaneously preloaded with glibenclamide (1.0 mM) and nicorandil (a selective opener of ATP-sensitive K channels, 1.0 mM), the CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were recovered to the considerable extent of the control release in comparison with that of glibenclamide-treatment only. Taken together, the present study demonstrates that glibenclamide enhances the adrenal CA secretion in response to stimulation of cholinergic (both nicotinic and muscarinic) receptors as well as by membrane depolarization from the isolated perfused rat adrenal glands. It seems that this facilitatory effect of glibenclamide may be mediated by enhancement of both Ca influx and the Ca release from intracellular store through the blockade of K channels in the rat adrenomedullary chromaffin cells. These results suggest that glibenclamide-sensitive K channels may play a regulatory role in the rat adrenomedullary CA secretion.

Tyrosine hydroxylase (TH, the rate limiting-enzyme in catecholamine synthesis) is regulated acutely via phosphorylation of 3 serine residues-Ser19, 31 and 40, and chronically via changes in TH protein levels. In this study, we aimed to investigate how TH is regulated in the brain, gut and adrenal gland as well as changes in mature brain-derived neurotrophic factor (mBDNF) and proBDNF levels in a low-dose (2 mg/kg, 5 days/week for 4 weeks) rotenone model of Parkinson's disease (PD). Rearing behaviour decreased by week 3 in the rotenone group (p < 0.01), with further decreases in rearing by week 4 (p < 0.001); however, TH remained unchanged in the substantia nigra (SN) and striatum; TH levels were also unaltered in other catecholaminergic cell groups of the brainstem such as A1C1 neurons or locus coeruleus. In the olfactory bulb, TH protein decreased (2.5-fold, p < 0.01) while Ser31 phosphorylation increased (1.4-fold, p < 0.05) in the rotenone group. In contrast, TH protein was increased in the adrenal gland (2-fold, p < 0.05) and colon (5-fold, p < 0.05) of rotenone rats. mBDNF levels were not changed in the SN but were significantly reduced in plasma and significantly increased in the colon (2-fold, p < 0.01) of rotenone-treated rats. This is the first study to assess TH and BDNF in the brain and periphery in the rotenone model before SN/striatum degeneration is evident. Together these results suggest that low-dose rotenone may have some potential to model the early stages of PD. Refereed/Peer-reviewed

The present study was designed to investigate the effect of carbonyl cyanide m-chlorophenylhydrazone (CCCP), a mitochondrial uncoupler, on secretion of catecholamines from the isolated perfused model of the rat adrenal gland and to establish the mechanism of its adrenomedullary secretion. The perfusion of CCCP (3 × 10 − 5 M) into an adrenal vein of for 90 min caused a great increase in catecholamine secretion. Tachyphylaxis to catecholamine-releasing effect of CCCP was not observed by repeated perfusion of it. The net catecholamine-releasing effects of CCCP were depressed by pretreament with pirenzepine (a selective muscarinic M 1 -receptor antagonist), chlorisondamine (a selective neuronal nicotinic receptor antagonist), nicardipine (an L-type Ca 2+ -channel antagonist), TMB-8 (an intracellular Ca 2+ -antagonist), and the perfusion of EGTA plus Ca 2+ -free medium, respectively. In the presence of CCCP (3 × 10 − 5 M), catecholamine secretory responses induced by ACh (5.32 × 10 − 3 M), high K + (5.6 × 10 − 2 M, a direct membrane depolarizer), DMPP (10 − 4 M, (a selective neuronal nicotinic receptor agonist), and McN-A-343 (10 − 4 M, (a selective muscarinic M 1 -receptor agonist) were significantly enhanced. CCCP also significantly enhanced the catecholamine secretory responses evoked by Bay-K-8644 (10 − 5 M), L-type Ca 2+ channel activator, and cyclopiazonic acid (10 − 5 M), an inhibitor of Ca 2+ -ATPase. Furthermore, the perfusion of FCCP (3 × 10 − 5 M), a similar mitochondrial uncoupler, into an adrenal vein of for 90 min also caused a great increase in catecholamine secretion in a similar pattern with CCCP. Taken together, the results demonstrate that CCCP causes the catecholamine secretion from the perfused rat adrenal medulla in a calcium-dependent fashion. It is thought that this catecholamine secretory enhancement of CCCP may be mediated by both cholinergic receptor stimulation and membrane depolarization, which are relevant to the cytoplasmic Ca 2+ increase by stimulation of the Ca 2+ influx as well as by the inhibition of Ca 2+ uptake into the cytoplasmic Ca 2+ stores (both endoplasmic reticulum and mitochondria in chromaffin cells). It also seems that protonophores, such as CCCP, suppress mitochondrial Ca 2+ uptake and increase the stimulated secretion of catecholamine by the secretagogues. These results indicate that mitochondria modulate catecholamine secretion by regulating the Ca 2+ mobilization for exocytosis.

We demonstrate that polysaccharides isolated from Salicornia herbacea (Salicornia polysaccharides, SPS) significantly induces nitric oxide (NO) production and inducible NO synthase (iNOS) transcription through the activation of nuclear factor-kappaB/Rel (NF-kappaB/Rel). SPS dose-dependently induced the production of NO in isolated mouse peritoneal macrophages and RAW 264.7, a mouse macrophage-like cell line. Moreover, iNOS gene expression was strongly induced by SPS in RAW 264.7 cells. To further investigate the mechanism responsible for the induction of iNOS gene expression, we investigated the effect of SPS on the activation of transcription factors including NF-kappaB/Rel and Oct, whose binding sites were located in the promoter of iNOS gene. Treatment of RAW 264.7 cells with SPS produced strong induction of NF-kappaB/Rel-dependent reporter gene expression, whereas Oct-dependent gene expression was not affected by SPS. Nuclear translocation and DNA binding activity of NF-kappaB/Rel was significantly induced by SPS. The treatment with NF-kappaB SN50, an inhibitor of NF-kappaB/Rel nuclear translocation, effectively inhibited the activation of NF-kappaB/Rel binding complexes and NO production. In conclusion, we demonstrate that SPS stimulates macrophages to express iNOS gene through the activation of NF-kappaB/Rel.

To study the effect of arecoline, an alkaloid isolated from Areca catechu, on the secretion of catecholamines (CA) evoked by cholinergic agonists and the membrane depolarizer from isolated perfused rat adrenal gland. Adrenal glands were isolated from male Sprague-Dawley rats. The adrenal glands were perfused with Krebs bicarbonate solution by means of a peristaltic pump. The CA content of the perfusate was measured directly using the fluorometric method. Arecoline (0.1–1.0 mmol/L) perfused into an adrenal vein for 60 min produced dose- and time-dependent inhibition in CA secretory responses evoked by acetylcholine (ACh) (5.32 mmol/L), 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP) (100 μmol/L for 2 min) and 3-(m-choloro-phenyl-carbamoyl-oxy)-2-butynyl trimethyl ammonium chloride (McN-A-343) (100 μmol/L for 2 min). However, lower doses of arecoline did not affect CA secretion of high K+ (56 mmol/L); higher doses greatly reduced CA secretion of high K+. Arecoline also failed to affect basal catecholamine output. Furthermore, in adrenal glands loaded with arecoline (0.3 mmol/L), CA secretory response evoked by Bay-K-8644 (10 μmol/L), an activator of L-type Ca2+ channels, was markedly inhibited, whereas CA secretion by cyclopiazonic acid (10 μmol/L), an inhibitor of cytoplasmic Ca2+-ATPase, was not affected. Nicotine (30 μmol/L), which was perfused into the adrenal gland for 60 min, however, initially enhanced ACh-evoked CA secretory responses. As time elapsed, these responses became more inhibited, whereas the initially enhanced high K+-evoked CA release diminished. CA secretion evoked by DMPP and McN-A-343 was significantly depressed in the presence of nicotine. Arecoline dose-dependently inhibits CA secretion from isolated perfused rat adrenal gland evoked by activation of cholinergic receptors. At lower doses arecoline does not inhibit CA secretion through membrane depolarization, but at larger doses it does. This inhibitory effect of arecoline may be mediated by blocking the calcium influx into the rat adrenal medullary chromaffin cells without the inhibition of Ca2+ release from the cytoplasmic calcium store. There seems to be a difference in the mode of action of nicotine and arecoline in rat adrenomedullary CA secretion.

The opening of the adenosine triphosphate (ATP)-sensitive potassium (KATP) channel has been proposed as a therapeutic approach for ischemia. Here we examined the opening effect of KR-31378 on the KATP channel using patch clamp recording in neuroblastoma 2a (N2a) cells and investigated the neuroprotective effect of KR-31378 in organotypic hippocampal slice cultures exposed to oxygen/glucose deprivation. The treatment with KR-31378 (10 microM) to N2a cells seemed to induce KATP channel opening in a dose dependent manner. The opening effect of KR-31378 was more significant than that of other known KATP channel openers. Pretreatment with KR-31378 (10 microM) showed a neuroprotective effect in both CA1 and CA3 regions and its effect was attenuated by glibenclamide in a dose dependent manner in both areas. This remarkable neuroprotective effect of KR-31378 seemed to be mediated by the opening of the KATP channel. These results suggest that KR-31378 could be a possible neuroprotective agent against cerebral ischemia.

Single-crystal 6,13-bis(triisopropylsilylethynyl) (TIPS) pentacene organic thin-film transistors (TFTs) were fabricated by ink-jet printing with bottom-contact structure. Direct printed organic single crystals were obtained using selective surface energy modification and mixed solvent system. The ink-jet printed organic single crystal TFT showed field-effect mobility as high as 1.7 cm2/Vs with post solvent annealing process.

The present study was attempted to investigate the effects of total ginseng saponin (GTS), panaxadiol-type (PDS) and panaxatriol-type saponin (PTS) on contractile responses of vasoconstrictors in aortic smooth muscle stripes of normotensive (NR) and spontaneous hypertensive rats (SHR). Phenylephrine (an adrenergic α1-receptor agonist) and high potassium (a membrane depolarizing agent) caused greatly contractile responses in both NR and AHR aorta, respectively. Phenylephrine- and high potassium-induced contractile responses were greater in NA than those in SHR aortic smooth muscle stripes. In NR, the contractile responses of high potassium (5.6×10.2 M) were not affected in the presence of GTS (300 μg/ml), PDS (300 μg/ml), and PTS (300 μg/ml), respectively whereas phenylephrine (10.6 M)-induced contractile responses were markedly inhibited. In SHR, the contractile responses of high potassium (5.6×10.2 M) were not affected in the presence of GTS (300 μg/ml), PDS (300 μg/ml), and moderate doses of PTS (150-300 μg/ml), respectively but greatly blocked by high concentration of PTS (600 μg/ml). Phenylephrine (10.6 M)-induced contractile responses were inhibited in a dose dependent fashion (150-600 μg/ml) by the pretreatment with PTS while not altered in the presence of GTS (300 μg/ml) and PDS (300 μg/ml), respectively. Taken together, these experimental results suggest that ginseng saponins cause vascular relaxation through blockade of adrenergic α1-receptors and some unknown mechanisms, and that there is some difference in sensitivity of vascular smooth muscle between NR and SHR in responses to ginseng saponins. It seems that panaxatriol type of some ginseng saponins has the greatest potency in vascular relaxation.

Introduction The present study was designed to examine whether methylene chloride (CH2Cl2) fraction extracted from Rubus coreanum affects the contractility of the isolated thoracic aortic strips and blood pressure of normotensive rats. Methods One of the common carotid arteries or of the femoral arteries was catheterized with a polyethylene tubing. The tubing was connected to a pressure transducer, and pulse of the mean arterial blood pressure was recorded on a biological polygraph continuously. Results The CH2Cl2 fraction (range, 200 to 800 μg/mL) significantly depressed both phenylephrine (PE, 10 μM)- and high K+ (56 mM)-induced contractile responses of the isolated thoracic aortic strips in a concentration-dependent fashion. In the simultaneous presence of Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME) (an inhibitor of nitric oxide [NO] synthase, 300 μM) and the CH2Cl2 fraction (400 μg/mL), both PE- and high K+-induced contractile responses were recovered to the significant level of the corresponding control response in comparison with inhibition of CH2Cl2 fraction treatment alone. Moreover, in the simultaneous presence of the CH2Cl2 fraction after pretreatment with 0.4% CHAPS (3-[(3-cholamidopropyl) dimethylammonio]-1-propane sulfonate), both PE- and high K+-induced contractile responses were recovered to the significant level of the corresponding control response compared to the inhibitory response of CH2Cl2 fraction treatment alone. Also, in anesthetized rats, the CH2Cl2 fraction (range, 0.3 to 3.0 mg/kg) injected into a femoral vein dose-dependently produced depressor responses. This hypotensive action of the CH2Cl2 fraction was greatly inhibited after treatment with phentolamine (1 mg/kg), chlorisondamine (1 mg/kg), L-NAME (3 mg/kg/30 min), or sodium nitroprusside (30 μg/kg/30 min). Intravenous infusion of the CH2Cl2 fraction (range, 1.0 to 10.0 mg/kg/30 min) markedly inhibited norepinephrine-induced pressor responses. Discussion Taken together, these results demonstrate that the CH2Cl2 fraction causes vascular relaxation in the isolated rat thoracic aortic strips as well as hypotensive action in anesthetized rats. These vasorelaxation and hypotension of the CH2Cl2 fraction seem to be mediated at least by the increased NO production through the activation of NO synthase of the vascular endothelium and the inhibitory adrenergic modulation. Electronic supplementary material The online version of this article (doi:10.1186/s40885-014-0006-1) contains supplementary material, which is available to authorized users.

The present study was attempted to investigate the effect of quinine on secretion of catecholamines (CA) evoked by cholinergic stimulation and membrane depolarization from the isolated perfused rat adrenal gland. The perfusion of quinine (15-150 microM) into an adrenal vein for 60 min produced dose- and time-dependent inhibition in CA secretion evoked by ACh (5.32 x 10(-3) M), high K+ (5.6 x 10(-2) M), DMPP (10(-4) M for 2 min), McN-A-343 (10(-4) M for 2 min), cyclopiazonic acid (10(-5) M for 4 min) and Bay-K-8644 (10(-5) M for 4 min). Also, under the presence of pinacidil (10(-4) M), which is also known to be a selective potassium channel activator, CA secretory responses evoked by ACh, high potassium, DMPPF McN-A-343, Bay-K-8644 and cyclopiazonic acid were also greatly reduced. When preloaded along with quinine (5 x 10(-5) M) and glibenclamide (10(-6) M), a specific blocker of ATP-regulated potassium channels, CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were recovered as compared to those of quinine-treatment only. Taken together, these results demonstrate that quinine inhibits CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors as well as by membrane depolarization through inhibiting influx of extracellular calcium and release in intracellular calcium in the rat adrenomedullary chromaffin cells. These findings suggest that activation of potassium channels may be involved at least in inhibitory action of quinine on CA secretion from the rat adrenal gland.

1. The present study attempted to investigate the effect of potassium channel openers on secretion of catecholamines (CA) evoked by cholinergic stimulation and membrane depolarization from rat isolated perfused adrenal gland. 2. The perfusion of pinacidil (30-300 microM) into an adrenal vein for 20 min produced dose-dependent inhibition of CA secretion evoked by acetylcholine (ACh; 5.32 mM), high K+ (56 mM), 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP; 100 microM for 2 min), 3-(m-chloro-phenyl-carbamoyl-oxy)-2-butynyl trimethyl ammonium chloride (McN-A-343; 100 microM for 2 min), cyclopiazonic acid (CPA; 10 microM for 4 min) and methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl)-pyri dine-5-carboxylate (Bay-K-8644; 10 microM for 4 min). 3. In the presence of minoxidil (100 microM), which is also known to be a potassium channel activator, CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and CPA were also significantly depressed. 4. In adrenal glands preloaded with pinacidil (100 microM) in the presence of glibenclamide (GB; 1 microM), a specific blocker of ATP-regulated potassium channels, CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and CPA were restored to a considerable extent of the control release as compared with that of pinacidil only. 5. These results suggest that pinacidil causes marked inhibition of CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors, as well as by membrane depolarization, indicating that this effect may be mediated by inhibiting influx of extracellular calcium and release of intracellular calcium in the rat adrenomedullary chromaffin cells. Furthermore, these findings suggest that these potassium channel opener-sensitive membrane potassium channels also play a modulatory role in regulating CA secretion.

Poly(ethylene glycol)(PEG) macromers terminated with acrylate groups and semi-interpenetrating polymer networks (SIPNs) composed of poly(epsilon-caprolactone)(PCL) and PEG macromer were synthesized to obtain a bioerodible hydrogel. Polymerization of PEG macromer resulted in the formation of cross-linked gels due to the multifunctionality of macromer. Glass transition temperature (Tg) and melting temperature (Tm) of PEG networks and PCL in the SIPNs were inner-shifted, indicating an interpenetration of PCL and PEG chains. Water content in the SIPNs increased with increasing PEG weight fraction due to the hydrophilicity of PEG. The amount of clonazepam (CNZ) released from the SIPNs increased with higher content in the SIPNs, lower drug loading, lower concentration of PEG macromer during the SIPNs preparation, and higher molecular weight of PEG. In particular, a combination with low PEG content and low CNZ solubility in water led to long-term constant release from these matrices in vitro and in vivo.

OBJECTIVES The present study was attempted to investigate the effects of pentobarbital-Na, one of the barbiturates which are known to depress excitatory synaptic transmission in the central nervous system at concentrations similar to those required for the induction and maintenance of anesthesia, on catecholamines (CA) secretion evoked by cholinergic stimulation and membrane-depolarization from the isolated perfused rat adrenal gland, and to clarify the mechanism of its action. METHODS Mature male Sprague-Dawley rats were anesthetized with thiopenal-Na (40 mg/kg, s.c.). The adrenal gland was isolated by the methods of Wakade. A cannula used for perfusion of the adrenal gland was inserted into the distal end of the renal vein. The adrenal gland was carefully removed from the animal and placed on a platform of a leucite chamber. RESULTS The perfusion of pentobarbital-Na(30-300 uM) into an adrenal vein for 20 min produced relatively dose-dependent inhibition in CA secretion evoked by ACh(5.32 mM), DMPP(100 uM for 1 min), McN-A-343(200 uM for 2 min), Bay-K-8644(10 uM) and high potassium(56 mM), while it did not affect the CA secretion of cyclopiazonic acid(10 uM). Also, in the presence of thiopental-Na (100 uM), CA secretory responses evoked by ACh, DMPP, McN-A-343 and high K+ were markedly depressed. Moreover, in adrenal glands preloaded with ketamine(100 uM for 20 min), which is known to be a dissociative anesthetic, CA secretion evoked by ACh, DMPP, McN-A-343 and high K+ were significantly attenuated. CONCLUSION Taken together, these experimental results suggest that pentobarbital-Na depresses CA release evoked by both cholinergic stimulation and membrane-depolarization from the isolated rat adrenal medulla and that this inhibitory activity may be due to the result of the direct inhibition of Ca++ influx into the chromaffin cells without any effect on the calcium mobilization from the intracellular store.

The present study was designed to investigate the characteristics of gintonin, one of components isolated from Korean Ginseng on secretion of catecholamines (CA) from the isolated perfused model of rat adrenal gland and to clarify its mechanism of action. Gintonin (1 to 30 µg/ml), perfused into an adrenal vein, markedly increased the CA secretion from the perfused rat adrenal medulla in a dose-dependent fashion. The gintonin-evoked CA secretion was greatly inhibited in the presence of chlorisondamine (1 µM, an autonomic ganglionic bloker), pirenzepine (2 µM, a muscarinic M1 receptor antagonist), Ki14625 (10 µM, an LPA1/3 receptor antagonist), amiloride (1 mM, an inhibitor of Na+/Ca2+ exchanger), a nicardipine (1 µM, a voltage-dependent Ca2+ channel blocker), TMB-8 (1 µM, an intracellular Ca2+ antagonist), and perfusion of Ca2+-free Krebs solution with 5mM EGTA (a Ca2+chelater), while was not affected by sodium nitroprusside (100 µM, a nitrosovasodialtor). Interestingly, LPA (0.3~3 µM, an LPA receptor agonist) also dose-dependently enhanced the CA secretion from the adrenal medulla, but this facilitatory effect of LPA was greatly inhibited in the presence of Ki 14625 (10 µM). Moreover, acetylcholine (AC)-evoked CA secretion was greatly potentiated during the perfusion of gintonin (3 µg/ml). Taken together, these results demonstrate the first evidence that gintonin increases the CA secretion from the perfused rat adrenal medulla in a dose-dependent fashion. This facilitatory effect of gintonin seems to be associated with activation of LPA- and cholinergic-receptors, which are relevant to the cytoplasmic Ca2+ increase by stimulation of the Ca2+ influx as well as by the inhibition of Ca2+ uptake into the cytoplasmic Ca2+ stores, without the increased nitric oxide (NO). Based on these results, it is thought that gintonin, one of ginseng components, can elevate the CA secretion from adrenal medulla by regulating the Ca2+ mobilization for exocytosis, suggesting facilitation of cardiovascular system. Also, these findings show that gintonin might be at least one of ginseng-induced hypertensive components.

A graphene oxide (GO)-based immunosensor is developed for the detection of interleukin-5 (IL-5), a key cytokine associated with asthma pathology and eosinophilia. The immunosensing platform utilizes the innate fluorescence of GO, not demanding biomolecules labeled with fluorescent dyes. The GO-based immunoassay exhibits high specificity for IL-5 among other cytokines and is not affected by nonspecific proteins in human serum.

We present a versatile and facile route for highly sensitive detection of analytes through coupling the enlargement of gold nanoparticles (Au NPs) with fluorescence decrease. The fluorescence intensity of dye molecules (e.g., fluorescein or rhodamine B) significantly decreased with the increasing concentration of reducing agents, such as hydrogen peroxide and hydroquinone. The sensitivity for the detection of reducing agents was much higher than other detection methods based on the absorbance measurement of enlarged gold nanoparticles or quantum dot-enzyme hybridization. We could successfully detect acetylthiocholine with the detection limit of several nM orders, using an enzymatic reaction by acetylcholinesterase, a key route for the detection of toxic organophosphate compounds. The fluorescence decreasing approach described in this work requires only a simple addition of fluorescence dye to the reaction solution without any chemical modification. The strategy of fluorescence decrease coupled with nanoparticle growth will be applied on the fluorescent substrate to develop detection templates for highly sensitive optical biosensor.

The present study was conducted to investigate the influence of arachidonic acid, which is known to be an important unsaturated fatty acid component of membrane phospholipids and to be liberated by phospholipase A2 action, on secretion of catecholamines (CA) from the isolated perfused rat adrenal glands and to clarify the mechanism of its action. Arachidonic acid (10 uM) perfused into an adrenal gland of the rat for 20 min caused a significant inhibition of CA secretion evoked by ACh (5.32 x 10(-3) M), DMPP (10(-4) M) and muscarine (10(-4) M) while it did not affect that induced by excess K+ (5.6 x 10(-2) M). Arachidonic acid, in the presence of ouabain (100 uM), an inhibitor of Na+, K(+) -ATPase, also produced a marked inhibitory effect of CA secretion evoked by ACh, DMPP and muscarine but did not modify the secretory effect of excess K+. The perfusion of arachidonic acid along with indomethacin (30 uM), which is an inhibitor of cyclooxygenase, for 20 min attenuated markedly CA secretory effect evoked by ACh, DMPP and muscarine while it did not influence that by excess K+. Prostaglandin F2 alpha perfused in a retrograde direction for 20 min inhibited greatly the CA secretion evoked by DMPP but did not affect the effect evoked by excess K+. All of arachidonic acid, ouabain, indomethacin and prostaglandin F2 alpha used in the present study did not affect the spontaneous basal release of CA in the perfused rat adrenal glands. Taken together, these experimental results suggest that arachidonic acid, as well as prostaglandin F2 alpha, cause the inhibitory action of CA secretion evoked by cholinergic receptor-mediated stimulation, but not by membrane depolarization, and also play a modulatory role in regulating CA secretion from the rat adrenal medulla.

The present sutdy aimed to determine whether olmesartan, an angiotensin II (Ang II) type 1 (AT(1)) receptor blocker, can influence the CA release from the isolated perfused model of the rat adrenal medulla. Olmesartan (5~50 µM) perfused into an adrenal vein for 90 min produced dose- and time-dependent inhibition of the CA secretory responses evoked by ACh (5.32 mM), high K(+) (56 mM, a direct membrane-depolarizer), DMPP (100 µM) and McN-A-343 (100 µM). Olmesartan did not affect basal CA secretion. Also, in adrenal glands loaded with olmesartan (15 µM), the CA secretory responses evoked by Bay-K-8644 (10 µM, an activator of voltage-dependent L-type Ca(2+) channels), cyclopiazonic acid (10 µM, an inhibitor of cytoplasmic Ca(2+) -ATPase), veratridine (100 µM, an activator of voltage-dependent Na(+) channels), and Ang II (100 nM) were markedly inhibited. However, at high concentrations (150~300 µM), olmesartan rather enhanced the ACh-evoked CA secretion. Taken together, these results show that olmesartan at low concentrations inhibits the CA secretion evoked by cholinergic stimulation (both nicotininc and muscarinic receptors) as well as by direct membrane depolarization from the rat adrenal medulla, but at high concentrations it rather potentiates the ACh-evoked CA secretion. It seems that olmesartan has a dual action, acting as both agonist and antagonist at nicotinic receptors of the isolated perfused rat adrenal medulla, which might be dependent on the concentration. It is also thought that this inhibitory effect of olmesartan may be mediated by blocking the influx of both Na(+) and Ca(2+) into the rat adrenomedullary chromaffin cells as well as by inhibiting the Ca(2+) release from the cytoplasmic calcium store, which is thought to be relevant to the AT(1) receptor blockade, in addition to its enhancement on the CA secreton.