• BMB Reports
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• v.45 no.8
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• pp.458-463
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• 2012

We investigated the mechanisms involved in KHG26377 regulation of glutamate dehydrogenase (GDH) activity, focusing on the roles of SIRT4 and SIRT3. Intraperitoneal injection of mice with KHG26377 reduced GDH activity with concomitant repression of glucose-induced insulin secretion. Consistent with their known functions, SIRT4 ribosylated GDH and reduced its activity, and SIRT3 deacetylated GDH, increasing its activity. However, KHG26377 did not affect SIRT4-mediated ADP-ribosylation/inhibition or SIRT3-mediated deacetylation/activation of GDH. KHG26377 had no effect on SIRT4 protein levels, and did not alter total GDH, acetylated GDH, or SIRT3 protein levels in pancreatic mitochondrial lysates. These results suggest that the mechanism by which KHG26377 inhibits GDH activity and insulin secretion does not involve ADP-ribosylation of GDH by SIRT4 or deacetylation of GDH by SIRT3.

• Molecules and Cells
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• v.25 no.1
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• pp.7-19
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• 2008

Complexins play a critical role in the control of fast synchronous neurotransmitter release. They operate by binding to trimeric SNARE complexes consisting of the vesicle protein Synaptobrevin and the plasma membrane proteins Syntaxin and SNAP-25, which are key executors of membrane fusion reactions. SNARE complex binding by Complexins is thought to stabilize and clamp the SNARE complex in a highly fusogenic state, thereby providing a pool of readily releasable synaptic vesicles that can be released quickly and synchronously in response to an action potential and the concomitant increase in intra-synaptic $Ca^{2+}$ levels. Genetic elimination of Complexins from mammalian neurons causes a strong reduction in evoked neurotransmitter release, and altered Complexin expression levels with consequent deficits in synaptic transmission were suggested to contribute to the etiology or pathogenesis of schizophrenia, Huntington's disease, depression, bipolar disorder, Parkinson's disease, Alzheimer's disease, traumatic brain injury, Wernicke's encephalopathy, and fetal alcohol syndrome. In the present review I provide a summary of available data on the role of altered Complexin expression in brain diseases. On aggregate, the available information indicates that altered Complexin expression levels are unlikely to have a causal role in the etiology of the disorders that they have been implicated in, but that they may contribute to the corresponding symptoms.

• Molecules and Cells
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• v.27 no.6
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• pp.681-687
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• 2009

We examined the effects of synthetic signal peptides, wild-type (WT) and export-defective mutant (MT) of ribose-binding protein, on the conformational changes of signal recognition particle 54 homologue (Ffh) in Escherichia coli. Upon interaction of Ffh with WT peptide, the intrinsic Tyr fluorescence, the transition temperature of thermal unfolding, and the GTPase activity of Ffh decreased in a peptide concentration-dependent manner, while the emission intensity of 8-anilinonaphthalene-1-sulfonic acid increased. In contrast, the secondary structure of the protein was not affected. Additionally, polarization of fluorescein-labeled WT increased upon association with Ffh. These results suggest that WT peptide induces the unfolded states of Ffh. The WT-mediated conformational change of Ffh was also revealed to be important in the interaction between SecA and Ffh. However, MT had marginal effect on these conformational changes suggesting that the in vivo functionality of signal peptide is important in the interaction with Ffh and concomitant structural change of the protein.

• Journal of Educational Research in Mathematics
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• v.13 no.2
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• pp.143-157
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• 2003

This paper is to make strides toward an enriched understanding of mathematics teacher learning and professional development. Different theoretical frameworks in understanding mathematics teacher learning are reviewed, followed by a discussion of the relationships of knowledge and teaching practice. This paper then analyses contemporary conceptions about effective professional development and, in particular, deals with teacher learning in inquiry communities. This paper introduces a research project describing transition processes from teacher- centered mathematics classroom culture to student-centered culture and analyzing teacher learning in communities and its concomitant change in teaching practice. On the basis of the emerging problems in doing the project, this paper finally addresses some crucial issues on teacher learning and professional development, including the management of an inquiry community, the description of teaching practice from the researcher's perspective, and the analysis of teacher learning in communities.

• ALGAE
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• v.29 no.1
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• pp.15-25
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• 2014

The number of species of non-native and invasive marine algae is growing, with concomitant public concern about native ecosystems and coastlines. Gelidium vagum, recently introduced from northeast Asia to Europe and North America, commonly occurs from the intertidal to subtidal zones in Korea, China, and Japan. To investigate the level of genetic diversity of native populations, we analyzed mitochondrial cox1 and cob from 108 specimens of G. vagum from Korea, China, eastern Russia, including from the Netherlands and USA. The haplotype network of individual and cox1 + cob datasets revealed no genetic structure in local populations, suggesting genetic flow between Korean populations. Our results corroborate a typical pattern of genetic diversity for introduced species, with low levels in introduced populations and high levels in native populations. All haplotypes were shared between the Netherlands and USA, but not between Korea and the Netherlands / USA except cox1. Additional sampling will identify donor populations in native northeast Asian waters. This is the first report of the utility of the mitochondrial coding cob sequences in red algae.

• Korean Journal of Pharmacognosy
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• v.41 no.1
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• pp.31-37
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• 2010

The Salvia plebeia R. which is the biennial plant belonging to the Labiatae department, grows naturally in the Korea entire area. Presently, its extract (SPRE) is known to have an anti-inflammation and anti-allergy activity, but there are a few evidences about it. SPRE inhibits pro-inflammatory cytokine such as TNF-$\alpha$ and IL-6 as well as nitric oxide (NO) production in lipopolysaccharide (LPS) treated- macrophages. The co-administration of SPRE during OVA sensitization significantly reduced total IgE levels in mice. The mice who received SPRE co-administered with OVA showed a significant increase in serum OVA-specific IgG2a/b levels. Spleen-cell cultures harvested from OVA-sensitized mice showed a significant decrease in Th2 cytokine levels with a concomitant increase in Th1 cytokine levels only when SPRE co-administered with OVA. These results demonstrate that SPRE can control the LPS-induced inflammatory reaction and prevent antigen-induced Th2 immune responses in mice.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.26 no.1
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• pp.19-23
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• 2020

Al-laminated packaging film incorporating ascorbic acid or tocopherol at inner food contact layer was tested in the potential to improve antioxidative preservation of powdered infant formula under CO₂-enriched atmosphere. Product of 200 g was packaged with the packaging film containing 0.3% antioxidant in sealant layer of low density polyethylene and stored at 30℃ for 286 days with periodic measurement of package atmosphere and product's quality attributes. The CO₂-flushed package resulted in shrinkage of tight contact between the product and the film not allowing gas sampling of package atmosphere after 140 days. Package of tocopherol-incorporated film allowed some ingress of oxygen after 112 days presumably due to its weakening of heat-seal area. The increased oxygen concentration in the tocopherol-added film package led to the concomitant increase of peroxide value, an index of lipid oxidation. On the other hand, packaging of ascorbic acid-added film pouch could suppress lipid oxidation marginally in consistent manner compared to control package without any antioxidant.

• Journal of Trauma and Injury
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• v.31 no.1
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• pp.38-42
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• 2018

A case of surgically treated intervertebral disc extrusion with intraoperatively confirmed intradiscal hematoma in a 30-year-old physical trainer is presented. Preoperative magnetic resonance imaging revealed downward migrating disc herniation, without definite suggestive findings of intradiscal hematoma. Intervertebral disc herniation with concomitant intradiscal hematoma is extremely rare, but could occur in patients who have excessive axial stress to the spine occupationally. In our case, the patient was an occupational physical trainer who had repetitive minor trauma to the lumbar spine. Although the patient did not have any clear history of major trauma to the spine, the intraoperative findings revealed intradiscal hematoma, which is very rare. The presence of intradiscal hematoma is to be suspected even when preoperative imaging studies shows indefinite findings of hematoma, considering the change in signal intensity of hematoma by time.

• The Korean Journal of Pharmacology
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• v.12 no.1
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• pp.31-44
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• 1976

It has been reported that many of the effects of digitalis glycosides could be mediated partly through the central nervous system. In this study the effects of ouabain given directly into the lateral ventricle of the brain on the renal function of the rabbit were investigated. Intraventricular ouabain elicited antidiuresis in doses ranging from 0.1 to $3\;{\mu}g$, exhibiting a rough dose-response relationship, and decreased the renal plasma flow, glomerular filtration rate and urinary excretion of sodium and potassium, concomitant with the decrease of urine flow. These decreases in urine flow, excretory rate of electrolytes significantly correlated with the decrease in renal plasma flow or glomerular filtration rate, suggesting that the antidiuresis might have been induced by the hemodynamic changes. Intravenous ouabain in a dose of $1\;{\mu}g$ did not affect the renal function. Systemic blood pressure as well as cardiac activity was not affected by the intraventricular ouabain. Effects of the intraventricular ouabain on renal function were abolished by the intravenous phentolamine-pretreatment but not affected by intraventricular phentolamine-pretreatment. Neither vasopressin infusion nor hydration did affect the renal effects of intraventricular ouabain. From these observations, it is suggested that the antidiuresis of intraventricular ouabain is induced by the increased sympathetic influence to the kidney.

• BMB Reports
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• v.30 no.2
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• pp.125-131
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• 1997

This work reports studies of the catalytic and structural properties of pyridoxal kinase (ATP: pyridoxal 5' -phosphotransferase, EC. 2.7.1.35), Pyridoxal kinase catalyzes the phosphorylation of vitamin $B_6$ (pyridoxal, pyridoxamine, pyridoxine) using ATP-Zn as a phosphoryl donor. The enzyme purified from brain tissues is made up of two identical subunits of 40 kDa each. Native enzyme was inhibited by a substrate analogue, pyridoxal-oxime. Limited chymotrypsin digestion of pyridoxal kinase yields two fragments of 24 and 16 kDa with concomitant loss of catalytic activity. These fragments were isolated by DEAE ion exchange chromatography and used for binding studies with fluorescent ATP and pyridoxal analogues. The spectroscopic properties of both fluorescent pyridoxal analogue and Anthraniloyl ATP (Ant-ATP) bound to the 24 kDa fragment are indistinguishable from those of both pyridoxal analogue and Ant-ATP bound to the native pyridoxal kinase, respectively. The small 16 kDa fragment, generated by proteolytic cleavage of the kinase, does not bind any of the substrate analogues. Binding characteristics of Ant-ATP were extensively studied by measuring the changes in fluorescence spectra at various conditions. From the results presented herein, it is postulated that the structural domain associated with catalytic activity comprises approximately one-half of the molecular mass of pyridoxal kinase (24 kDa). whereas the remaining portion (16 kDa) of the enzyme contains a regulatory binding domain.