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Choi S, Lee GJ, Chae SJ, Kang SW, Yin CS, Lee SH, Choi SK, Park HK. Potential neuroprotective effects of acupuncture stimulation on diabetes mellitus in a global ischemic rat model. Physiol Meas 2010; 31:633-47. [PMID: 20308770 DOI: 10.1088/0967-3334/31/5/003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Acupuncture (ACU) is known to be effective in ischemia treatment, and glutamate (GLU) excitotoxicity is an important factor in neuronal cell death. We observed the effect of ACU on cerebral blood flow (%CBF) and DeltaGLU (the changes in GLU release) in the ischemic stroke rat model of diabetic mellitus (DM). A global ischemia was induced using the eleven-vessel occlusion (11-VO) method in 14 Sprague-Dawley rats (DM), which were randomly divided into two groups: the control group and the ACU-treatment group. Extracellular DeltaGLU was assessed using an intra-cerebral biosensor system measuring 256 samples per second, simultaneously with %CBF and electroencephalogram. ACU stimulation was applied to ACU points GB34 and GB39 during the ischemic period. Twenty-three diagnostic parameters were proposed first for a detailed analysis of changes in %CBF and GLU release during ischemia/reperfusion. ACU rats showed a significant decrease in ischemic (p < 0.05) and reperfusion %CBF (p < 0.0001) than control rats, and a significantly larger decrease in ischemic DeltaGLU (p < 0.05) and peak level of reperfusion DeltaGLU (p < 0.005) than control rats. From these results, we suggest that ACU stimulation is responsible for the potential protection of neurons through suppression of %CBF response in the increased plasma osmolality and extracellular DeltaGLU in diabetic rats under ischemic conditions.
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Choi S, Kang SW, Lee GJ, Choi SK, Chae SJ, Park HK, Chung JH. Real-time ischemic condition monitoring in normoglycemic and hyperglycemic rats. Physiol Meas 2010; 31:439-50. [PMID: 20150688 DOI: 10.1088/0967-3334/31/3/011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
An increase in excitotoxic amino acid glutamate (GLU) concentration associated with neuronal damage might be the cause of the ischemic damage observed in stroke patients suffering from hyperglycemia. However, the effect has never been investigated by real-time in vivo monitoring. Therefore, this study examined the effects of the functional responses of ischemia-evoked electroencephalography (EEG), cerebral blood flow (%CBF) and DeltaGLU in hyperglycemia through real-time in vivo monitoring. Five Sprague-Dawley rats were treated with streptozocin (hyperglycemia) and five normal rats were used as the controls. Global ischemia was induced using an 11-vessel occlusion model. The experimental protocols consisting of 10 min pre-ischemic, 10 min ischemic and 40 min reperfusion periods were applied to both groups. Under these conditions, the responses of the ischemia-evoked EEG, %CBF and DeltaGLU were monitored in real time. The EEG showed flat patterns during ischemia followed by poor recovery during reperfusion. The peak reperfusion %CBF was decreased significantly in the hyperglycemia group compared to the control group (p < 0.05, n = 5). The extracellular DeltaGLU releases increased significantly during ischemia (p < 0.0001, n = 5) and reperfusion (p < 0.001, n = 5) in the hyperglycemia group compared to the control group. The decrease in reperfusion %CBF during short-term hyperglycemia might be related to the increased plasma osmolality, decreased adenosine levels and swollen endothelial cells with decreased vascular luminal diameters under hyperglycemic conditions. And, the increase in DeltaGLU during short-term hyperglycemia might be related to the neurotoxic effects of the high extracellular concentrations of DeltaGLU and the inhibition of GLU uptake.
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Jung MY, Kang SW, Kim SK, Kim HJ, Yun DH, Yim SV, Hong SJ, Chung JH. The interleukin-1 family gene polymorphisms in Korean patients with rheumatoid arthritis. Scand J Rheumatol 2010; 39:190-6. [DOI: 10.3109/03009740903447028] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Leclerc B, Kang SW, Mauro LJ, Kosonsiriluk S, Chaiseha Y, El Halawani ME. Photoperiodic modulation of clock gene expression in the avian premammillary nucleus. J Neuroendocrinol 2010; 22:119-28. [PMID: 20002961 DOI: 10.1111/j.1365-2826.2009.01942.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The premammillary nucleus (PMM) has been shown to contain a daily endogenous dual-oscillation in dopamine (DA)/melatonin (MEL) as well as c-fos mRNA expression that is associated with the daily photo-inducible phase of gonad growth in turkeys. In the present study, the expression of clock genes (Bmal1, Clock, Cry1, Cry2, Per2 and Per3) in the PMM was determined under short (8 : 16 h light/dark cycle) and long (16 : 8 h light/dark cycle) photoperiods relative to changes associated with the diurnal rhythm of DA and MEL. Constant darkness (0 : 24 h light/dark cycle) was used to assess the endogenous response of clock genes. In addition, light pulses were given at zeitgeber time (ZT) 8, 14 and 20 to ascertain whether clock gene expression is modulated by light pulse stimulation and therefore has a daily phase-related response. In the PMM, the temporal clock gene expression profiles were similar under short and long photoperiods, except that Per3 gene was phase-delayed by approximately 16 h under long photoperiod. In addition, Cry1 and Per3 genes were light-induced at ZT 14, the photosensitive phase for gonad recrudescence, whereas the Clock gene was repressed. Gene expression in established circadian pacemakers, the visual suprachiasmatic nucleus (vSCN) and the pineal, was also determined. Clock genes in the pineal gland were rhythmic under both photoperiods, and were not altered after light pulses at ZT 14, which suggests that pineal clock genes may not be associated with the photosensitive phase and reproductive activities. In the vSCN, clock gene expression was phase-shifted depending on the photoperiod, with apexes at night under short day length and during the day under long day length. Furthermore, light pulses at ZT 14 induced the Per2 gene, whereas it repressed the Bmal1 gene. Taken together, the changes in clock gene expression observed within the PMM were unique compared to the pineal and vSCN, and were induced by long photoperiod and light during the daily photosensitive phase; stimuli that are also documented to promote reproductive activity. These results show that Cry1 and Per3 are involved in the photic response associated with the PMM neuronal activation and are coincident with an essential circadian mechanism (photosensitive phase) controlling the reproductive neuroendocrine system.
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Choi K, Ryu SW, Song S, Choi H, Kang SW, Choi C. Caspase-dependent generation of reactive oxygen species in human astrocytoma cells contributes to resistance to TRAIL-mediated apoptosis. Cell Death Differ 2009; 17:833-45. [PMID: 19876066 DOI: 10.1038/cdd.2009.154] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), a member of the TNF family of cytokines, causes apoptosis by caspase activation in various cell types, particularly in transformed cells. Numerous types of tumors are relatively resistant to TRAIL-induced cytotoxicity; however, the reasons for this are not yet fully understood. We report here a new signal transduction pathway involving protein kinase Cdelta (PKCdelta), NADPH oxidase 4 (NOX4) and reactive oxygen species (ROS), that inhibits caspase-dependent cell death induced by TRAIL ligation in human malignant astrocytoma cells. In our experiments, TRAIL ligation-induced generation of intracellular ROS through caspase-dependent proteolytic activation of PKCdelta and subsequent activation of the NOX4 complex. Suppression of intracellular ROS induction using various pharmacological inhibitors or PKCdelta- or NOX4-specific RNA interference enhanced the enzymatic activity of caspase-3 by blocking the oxidative modification of its catalytic cysteine residue, resulting in marked augmentation of TRAIL-mediated cell death. These results collectively indicate that TRAIL-induced activation of PKCdelta and NOX4 can modulate TRAIL-mediated apoptosis by promoting oxidative modification of active caspase-3 in a negative-feedback manner.
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Kang SW, Chung SE, Shin WJ, Lee JH. Polypoidal choroidal vasculopathy and late geographic hyperfluorescence on indocyanine green angiography. Br J Ophthalmol 2009; 93:759-64. [DOI: 10.1136/bjo.2008.145862] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Lee GJ, Choi SK, Eo YH, Kang SW, Choi S, Park JH, Lim JE, Hong KW, Jin HS, Oh BS, Park HK. The effect of extracellular glutamate release on repetitive transient ischemic injury in global ischemia model. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2009; 13:23-6. [PMID: 19885022 DOI: 10.4196/kjpp.2009.13.1.23] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
During operations, neurosurgeons usually perform multiple temporary occlusions of parental artery, possibly resulting in the neuronal damage. It is generally thought that neuronal damage by cerebral ischemia is associated with extracellular concentrations of the excitatory amino acids. In this study, we measured the dynamics of extracellular glutamate release in 11 vessel occlusion (VO) model to compare between single occlusion and repeated transient occlusions within short interval. Changes in cerebral blood flow were monitored by laser-Doppler flowmetry simultaneously with cortical glutamate level measured by amperometric biosensor. From real time monitoring of glutamate release in 11 VO model, the change of extracellular glutamate level in repeated transient occlusion group was smaller than that of single occlusion group, and the onset time of glutamate release in the second ischemic episode of repeated occlusion group was delayed compared to the first ischemic episode which was similar to that of single 10 min ischemic episode. These results suggested that repeated transient occlusion induces less glutamate release from neuronal cell than single occlusion, and the delayed onset time of glutamate release is attributed to endogeneous protective mechanism of ischemic tolerance.
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Lee HJ, Lee MS, Kim JS, Kim ER, Kang SW, Kim SK, Chung JH, Yoon KL, Han MY, Cha SH. The relationship between catechol-O-methyltransferase gene polymorphism and coronary artery abnormality in Kawasaki disease. KOREAN JOURNAL OF PEDIATRICS 2009. [DOI: 10.3345/kjp.2009.52.1.87] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Kang SW, Leclerc B, Mauro LJ, El Halawani ME. Serotonergic and catecholaminergic interactions with co-localised dopamine-melatonin neurones in the hypothalamus of the female turkey. J Neuroendocrinol 2009; 21:10-9. [PMID: 19094089 DOI: 10.1111/j.1365-2826.2008.01804.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Serotonin and catecholamines (dopamine, norepinephrine, epinephrine) have important roles as neurotransmitters in avian reproduction, but their anatomical relationship to the neuroendocrine circuitry that regulates reproduction is poorly understood. Our previous studies have shown that co-localised dopamine-melatonin (DA-MEL) neurones in the avian premammillary nucleus (PMM) are active during periods of photoresponsiveness and, therefore, are potentially photosensitive neurones. Because serotonergic and catecholaminergic neurotransmitters are important regulators of reproductive function in the female turkey, we hypothesised that the serotonergic/catecholaminergic neurones within the brainstem might interact with PMM DA-MEL neurones and constitute an important circuit for reproductive function. To examine this possible interaction, the retrograde fluorescent tract tracer, 1,1'dioctadecyl-3,3,3'3'-tetramethyleindocarbocyanine perchlorate (DiI) was injected into the PMM, and combined with serotonin, tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DBH) and phenyl N-methyltransferse (PNMT) immunocytochemistry to reveal neuroanatomical connections. Changes in the activities of serotonergic, dopaminergic, adrenergic and noradrenergic neuronal systems projecting to the PMM were measured at different reproductive states with in situ hybridisation (ISH) techniques, using tryptophan hydroxylase 2 (TPH2) and TH mRNA expression, respectively. Cells labelled with DiI were found in anatomically discrete areas in or near the hypothalamus and the brainstem. Double immunocytochemistry confirmed that there were serotonin, DBH and PNMT fibres in close apposition to DA-MEL neurones. TPH2 mRNA expression in serotonin neurones was found in several nuclei, and its most abundant mRNA expression was seen in the nucleus Locus ceruleus of laying and incubating hens. TH mRNA expression levels in the six catecholaminegic areas labelled with DiI was measured across the different reproductive states. In the nucleus tractus solitarius (adrenergic), the highest level of TH mRNA expression was found in photorefractory hens and the lowest level in incubating hens. These observed patterns of serotonin/catecholamine neuronal distribution and their variable interactions with PMM DA-MEL neurones during different reproductive states may offer a significant neuroanatomical basis for understanding the control of avian reproductive seasonality.
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Park BS, Park YJ, Kim YJ, Kang SW, Kim YH, Shin JH, Yoon YC, Kim YW. A case of disseminated Nocardia farcinica diagnosed through DNA sequencing in a kidney transplantation patient. Clin Nephrol 2008; 70:542-545. [PMID: 19049715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
Nocardia is a rare gram-positive bacteria causing opportunistic infection, and belongs to the aerobic Actinomycetes group. As the mortality in the immunocompromised patients with nocardiosis is high, early diagnosis and treatment is very important. However, clinical manifestations of infection caused by Nocardia are very variable and early diagnosis is limited by the difficulty in obtaining specimens and its isolation. Rapid diagnosis of Nocardia infection may allow for earlier effective therapy, thus improving patient outcome. We report a case of Nocardia farcinica diagnosed by DNA sequencing through blood culture in a renal transplant recipient with severe pneumonia and multiple brain abscesses.
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Kang SW, Park SJ, Kim YW, Kim YH, Sohn HS, Yoon YC, Joo H, Jeong KH, Lee SH, Lee TW, Ihm CG. Association of MCP-1 and CCR2 polymorphisms with the risk of late acute rejection after renal transplantation in Korean patients. Int J Immunogenet 2008; 35:25-31. [PMID: 18186797 PMCID: PMC2228509 DOI: 10.1111/j.1744-313x.2007.00725.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Among the factors modulating transplant rejection, chemokines and their respective receptors deserve special attention. Increased expression of monocyte chemoattractant protein-1 (MCP-1) and its corresponding receptor (chemokine receptor-2, CCR2) has been implicated in renal transplant rejection. To determine the impact of the MCP-1-2518G and CCR2-64I genotypes on renal allograft function, 167 Korean patients who underwent transplantation over a 25-year period were evaluated. Genomic DNA was genotyped using polymerase chain reaction followed by restriction fragment length polymorphism analysis. Fifty-five (32.9%) patients were homozygous for the MCP-1-2518G polymorphism. Nine (5.4%) patients were homozygous for the CCR2-64I polymorphism. None of the investigated polymorphism showed a significant shift in long-term allograft survival. However, a significant increase was noted for the risk of late acute rejection in recipients who were homozygous for the MCP-1-2518G polymorphism (OR, 2.600; 95% CI, 1.125–6.012; P = 0.022). There was also an association between the MCP-1-2518G/G genotype and the number of late acute rejection episodes (P = 0.024). Although there was no difference in the incidence of rejection among recipients stratified by the CCR2-V64I genotype, recipients with the CCR2-V64I GG genotype in combination with the MCP-1-2518G/G genotype had a significantly higher risk of acute or late acute rejection among the receptor-ligand combinations (P = 0.006, P = 0.008, respectively). The MCP-1 variant may be a marker for risk of late acute rejection in Korean patients.
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Byun HS, Song JK, Kim YR, Piao L, Won M, Park KA, Choi BL, Lee H, Hong JH, Park J, Seok JH, Lee YJ, Kang SW, Hur GM. Caspase-8 has an essential role in resveratrol-induced apoptosis of rheumatoid fibroblast-like synoviocytes. Rheumatology (Oxford) 2008; 47:301-8. [PMID: 18276737 DOI: 10.1093/rheumatology/kem368] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVE Resveratrol is a naturally occurring polyphenol, which possesses chemotherapeutic potential through its ability to trigger apoptosis. The objective of this study was to investigate the major determinant for the apoptotic cell death induction by resveratrol in fibroblast-like synoviocytes (FLS) derived from patients with RA. METHODS The effect of resveratrol on apoptotic cell death was quantified in a population of subG1 in RA FLS by flow cytometry. The underlying signalling mechanism for apoptotic death was examined by analysing mitochondrial membrane potential, activation of the caspase cascade and translocation of Bid. RESULTS We show that activation of caspase-8 is essential for triggering resveratrol-induced apoptotic signalling via the involvement of the mitochondrial pathway in RA FLS. Our findings also suggest that this enhanced apoptosis caused by resveratrol occurred in RA FLS irrespective of p53 status. Exposure to resveratrol caused extensive apoptotic cell death, along with a caspase-dependent (activation of caspase-9 and -3, poly ADPribose polymerase (PARP) cleavage and mitochondrial cytochrome c release) or caspase-independent [translocation of apoptosis-inducing factor (AIF) to the nucleus] signalling pathway. Analysis of upstream signalling events affected by resveratrol revealed that the activated caspase-8 triggered mitochondrial apoptotic events by inducing Bid cleavage without any alteration in the levels of Bax, Bcl-xL or Bcl2. The caspase-8 inhibitor or over-expression of crmA abrogated cell death induced by resveratrol and prevented processing of the downstream cascade. CONCLUSION The results suggest that resveratrol causes activation of caspase-8, which in turn results in modulation of mitochondrial apoptotic machinery to promote apoptosis of RA FLS.
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Kim EM, Yang HS, Kang SW, Ho JN, Lee SB, Um HD. Amplification of the gamma-irradiation-induced cell death pathway by reactive oxygen species in human U937 cells. Cell Signal 2008; 20:916-24. [PMID: 18262755 DOI: 10.1016/j.cellsig.2008.01.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 01/02/2008] [Accepted: 01/03/2008] [Indexed: 02/08/2023]
Abstract
Given the critical involvement of reactive oxygen species (ROS) in cell death, their hierarchical status in the cell pathway has been analyzed by many investigators. However, it has been shown that ROS can act either upstream or downstream of various death mediators depending on experimental settings. To investigate whether the contrasting relationships may exist in a single model system, human U937 cells were irradiated with lethal doses of gamma-rays. This resulted in a promotion of mitochondrial ROS production, which was found to be induced via sequential actions of c-Jun N-terminal kinase (JNK), Bax, and caspase-3. Interestingly, the induced ROS, in turn, re-activated JNK, Bax, and caspase-3 in the same model system. Consistently, the blockade of Bax action by RNA interference or Bcl-2 overexpression abolished the activation of JNK induced after, but not before, the production of ROS. Bcl-2 overexpression also blocked the translocation of Bax from the cytosol to the mitochondria only after the induction of ROS. Functional analyses revealed that the initial ROS-independent activations of JNK, Bax, and caspase-3 are not sufficient for cell death, and thus, should be re-activated by ROS in order to kill the cells. These findings suggest that ROS do not simply mediate the lethal action of gamma-irradiation, but actually amplify it by forming a feedback loop between a downstream effector caspase and the upstream initiation signals leading to the activation of JNK. This role for ROS appears to allow Bcl-2 to block the signaling events, which are initially induced upstream.
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Kang SW, Thayananuphat A, Bakken T, El Halawani ME. Dopamine-melatonin neurons in the avian hypothalamus controlling seasonal reproduction. Neuroscience 2007; 150:223-33. [PMID: 17935892 DOI: 10.1016/j.neuroscience.2007.08.031] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2007] [Revised: 08/03/2007] [Accepted: 09/07/2007] [Indexed: 10/22/2022]
Abstract
Day length cues are used by temperate zone birds to time seasonal changes in reproductive physiology and behavior. However, the neuronal and neurochemical circuits used to measure day length (photoperiodic time measurement; PTM), transduce light information and activate the reproductive neuroendocrine system have not been definitely established. Recent findings from our laboratory provide data showing dopamine (DA) neurons within the premammillary nucleus (PMM) of the caudal turkey hypothalamus are putative photoreceptive neurons. These neurons reach threshold activation when a brief pulse of light is provided during the photo-inducible phase for photosexual stimulation. To further clarify the role of PMM neurons in coding daylight information, we showed that by using double-label immunocytochemistry (ICC) these neurons are immunoreactive (ir) to both tyrosine hydroxylase (TH; the rate limiting enzyme in DA biosynthesis) and melatonin (MEL). Moreover, we found these neurons to express tryptophan hydroxylase 1 (TPH1; the first enzyme in MEL biosynthesis) and 5-HT N-acetyltransferase (AANAT; a key regulatory enzyme in MEL synthesis) mRNAs but not neuronal tryptophan hydroxylase 2 mRNA (TPH 2; the rate limiting enzyme in 5-HT pathway). Both TH and TPH1 mRNAs were shown to cycle rhythmically, and with opposite phases, in PMM neurons of birds kept under a diurnal illumination cycle (12-h light/dark; LD). These neurons could also generate 24 h TH and TPH1 mRNA expression rhythms with the same phase relationship in constant light (LL) and constant dark (DD). In addition, the expression patterns and amplitudes of TH and TPH1 mRNAs were different between long and short photoperiods. These findings may form the basis for an endogenous dual-oscillator circadian system within PMM DA-MEL co-localized neurons controlling reproductive seasonality in birds.
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Lee YJ, Kang SW, Song JK, Park JJ, Bae YD, Lee EY, Lee EB, Song YW. Serum galectin-3 and galectin-3 binding protein levels in Behçet's disease and their association with disease activity. Clin Exp Rheumatol 2007; 25:S41-S45. [PMID: 17949550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
OBJECTIVE To determine the serum levels of galectin-3 (Gal-3) and galectin-3 binding protein (G3BP) and to evaluate the associations between clinical features and these levels in patients with Behçet's disease (BD). METHODS Fifty patients with BD (mean age 40.6 +/- SEM 1.4 years; 21 males, 29 females; 26 active and 24 inactive patients), 20 patients with rheumatoid arthritis (RA), and 20 patients with systemic lupus erythematosus (SLE) were enrolled. Clinical features of BD patients including BD activity and severity over the previous 4 weeks were reviewed and serum levels of Gal-3 and G3BP were determined using enzyme-linked immunosorbent assays (ELISA). RESULTS Serum Gal-3 levels were significantly higher in total BD patients than in healthy controls (mean +/- SEM, 10.68 +/- 0.93 versus 7.59 +/- 0.48 ng/mL; p = 0.0042 by Student's t-test), and active BD patients had significantly higher levels of serum Gal-3 than inactive patients and controls (13.08 +/- 1.53 in active BD, 8.08 +/- 0.71 ng/mL in inactive BD; p = 0.000039 by one way ANOVA). Although mean G3BP serum levels were not different in total BD patients and controls, active BD patients (6806.63 +/- 468.58 ng/mL) had higher G3BP levels than controls (5421.05 +/- 286.02 ng/mL; p = 0.031 by one way ANOVA). Additionally, serum Gal-3 significantly increased in patients with RA (p = 0.019 by t-test) and SLE (p = 0.00069) and G3BP increased in patients with SLE (p = 0.000012), compared to those in healthy controls. When we analyzed for associations with clinical features over the previous 4 weeks, Gal-3 was associated with orogenital ulcers (p = 0.036 by t-test) and time elapsed from symptom onset (p = 0.032, Pearson's coefficient = 0.314). Serum concentrations of Gal-3 (p = 0.013) and G3BP (p = 0.032) were positively correlated with the BD severity score for the previous 4 weeks. Gal-3 levels were significantly correlated with TNF-alpha (p = 0.048, Pearson's coefficient = 0.281) and G3BP levels were correlated with levels of C-reactive protein (p = 0.021, Pearson's coefficient = 0.329) in total BD patients. In multivariate analysis of all cytokines levels, only Gal-3 was significantly related to BD activity or severity for the previous 4 weeks. CONCLUSION These results suggest that serum levels of Gal-3 and G3BP are increased in active BD patients and Gal-3 can be a new biomarker indicating disease activity in BD although their increments are not disease-specific.
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Thayananuphat A, Kang SW, Bakken T, Millam JR, El Halawani ME. Rhythmic dependent light induction of gonadotrophin-releasing hormone-I expression and activation of dopaminergic neurones within the premammillary nucleus of the turkey hypothalamus. J Neuroendocrinol 2007; 19:399-406. [PMID: 17388816 DOI: 10.1111/j.1365-2826.2007.01545.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Our previous studies using turkey hens have demonstrated that c-fos mRNA (a marker of neuronal activation) is expressed in gonadotrophin-releasing hormone-I (GnRH-I), vasoactive intestinal peptide (VIP) and dopamine (DA) neurones following electrical stimulation in the preoptic area. DA has been shown to have both stimulatory and inhibitory effects on the GnRH-I/luteinising hormone (LH), follicle-stimulating hormone (FSH) and VIP/prolactin (PRL) systems. To identify the DA neurones that mediate the stimulatory influences of photoperiod on the reproductive system, we examined c-fos mRNA induction in DA, GnRH-I, and VIP neurones in the turkey hypothalamus using a dark-interruption experimental design. A 30-min light period was provided to short day (6L : 18D) photosensitive turkeys at times when birds were responsive to light (14 h after first light) and at times when birds were unresponsive to light (8 h and 20 h after first light). The only area where DA neurones were activated when the birds were provided with light was in the nucleus premammillaris (PMM). The number of activated DA neurones was significantly greater when light was provided at 14 h (during the photoinducible phase) than at 8 h or 20 h. At 14 h, there was also an increase in the number of GnRH-I neurones activated in the area of the nucleus commissura pallii (nCPa), as well as an up-regulation of GnRH-I mRNA expression. No expression of c-fos mRNA was observed in VIP neurones in the nucleus infundibularis or up-regulation of VIP mRNA expression in any of the experimental light treatments. These results are the first evidence to demonstrate a relationship between the dopaminergic system in the PMM and the GnRH-I system in the nCPa during the photoinduction of avian reproductive activity.
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Thayananuphat A, Kang SW, Bakken T, Millam JR, El Halawani ME. Rhythm-dependent light induction of the c-fos gene in the turkey hypothalamus. J Neuroendocrinol 2007; 19:407-17. [PMID: 17388817 DOI: 10.1111/j.1365-2826.2007.01544.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Day length (photoperiod) is a powerful synchroniser of seasonal changes in the reproductive neuroendocrine activity in temperate-zone birds. When exposed to light during the photoinducible phase, reproductive neuroendocrine responses occur. However, the neuroendocrine systems involved in avian reproduction are poorly understood. We investigated the effect of light exposure at different circadian times upon the hypothalamus and components of the circadian system, using c-fos mRNA expression, measured by in situ hybridisation, as an indicator of light-induced neuronal activity. Levels of c-fos mRNA in these areas were compared after turkey hens (on a daily 6-h light period) had been exposed to a 30-min period of light occurring at 8, 14, or 20 h after the onset of first light of the day (subjective dawn). Non-photostimulated control birds were harvested at the same times. In birds, photostimulated within the photoinducibile phase (14 h), in contrast to before or after, c-fos mRNA was significantly increased in the nucleus commissurae pallii (nCPa), nucleus premamillaris (PMM), eminentia mediana (ME), and organum vasculosum lamina terminalis (OVLT). Photostimulation increased c-fos mRNA expression in the pineal gland, nucleus suprachiasmaticus, pars visualis (vSCN) and nucleus inferioris hypothalami compared to that of their corresponding nonphotostimulated controls. However, the magnitudes of the responses in these areas were similar irrespective of where in the dark period the pulses occurred. No c-fos mRNA was induced in the nucleus infundibulari, in response to the 30-min light period at any of the circadian times tested. The lack of c-fos up-regulation in the pineal gland and vSCN following photostimulation during the photoinducible phase lends credence to the hypothesis that these areas are not involved in the photic initiation of avian reproduction. On the other hand, c-fos mRNA increases in the nCPa, ME, and OVLT support other studies showing that these areas are involved in the onset of reproductive behaviour initiated by long day lengths. The present study provides novel data showing that the PMM in the caudal hypothalamus is involved in the neuronally mediated, light-induced initiation of reproductive activity in the turkey hen.
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Kang SW. Two axes in platelet-derived growth factor signaling: tyrosine phosphorylation and reactive oxygen species. Cell Mol Life Sci 2007; 64:533-41. [PMID: 17221164 PMCID: PMC11138445 DOI: 10.1007/s00018-007-6437-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The tyrosine phosphorylation cascade is a hallmark of platelet-derived growth factor (PDGF)- induced signal transduction. The amplitude and propagation of the tyrosine phosphorylation signal relies on the balance between tyrosine kinase and tyrosine phosphatase. The tyrosine kinase is latent in the absence of stimulation, whereas the tyrosine phosphatase is highly and constitutively active. Therefore, the kinase activation should be accompanied by temporal and spatial inactivation of tyrosine phosphatase to achieve the robust amplification of tyrosine phosphorylation. For the past decade, reactive oxygen species have been receiving a great deal of attention with regard to their ability to shut down tyrosine phosphatase activities in a reversible manner. In this article, the crosstalk between tyrosine phosphorylation and reactive oxygen species in PDGF signaling is discussed.
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Park DG, Kang SW. Development of reusable and expandable communication for wearable medical sensor network. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:5380-3. [PMID: 17271559 DOI: 10.1109/iembs.2004.1404502] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To meet the various communication requirements of the wearable medical sensor network, the reusable and expandable wireless communications platform has been developed. The connection between the central monitoring unit and the sensors around the body is implemented using the Bluetooth technology. And the data can be uploaded and downloaded to an external Internet server by the CDMA modem or Bluetooth LAN access point (LAP). The system used PDA as a central monitoring unit which records and displays the data received.
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Kang SW, Park CH, Hong SI, Kim SW. Production of penicillic acid by Aspergillus sclerotiorum CGF. BIORESOURCE TECHNOLOGY 2007; 98:191-7. [PMID: 16458001 DOI: 10.1016/j.biortech.2005.11.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2004] [Revised: 11/21/2005] [Accepted: 11/24/2005] [Indexed: 05/06/2023]
Abstract
The production of penicillic acid by Aspergillus sclerotiorum CGF for the biocontrol of Phytophthora disease was investigated in submerged fermentation using media composed of different nutrients. Soluble starch was found to be the most effective substrate among the carbon sources used, and produced the highest penicillic acid concentration of 2.98 mg ml(-1). When organic nitrogen sources were used, pharmamedia, yeast extract, and polypeptone-S were found to be suitable organic nitrogen sources (2.46-2.71 mg ml(-1)). The production of penicillic acid was not detected in when inorganic nitrogen sources were used. Only Na2HPO4, among the metal ions and phosphate salts tested, increased the production of penicillic acid (approximately 20%). When A. sclerotiorum CGF was cultured in optimal medium [8.0% (w/v) soluble starch, 0.6% (w/v) yeast extract, and 0.3% (w/v) Na2HPO4], maximum penicillic acid concentration (approximately 9.40 mg ml(-1)) and cell mass (approximately 17.4 g l(-1)) were obtained after 12 days.
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Neupane K, Kang SW, Sharma S, Carney D, Meyer T, Mehl GH, Allender DW, Kumar S, Sprunt S. Dynamic light scattering study of biaxial ordering in a thermotropic liquid crystal. PHYSICAL REVIEW LETTERS 2006; 97:207802. [PMID: 17155716 DOI: 10.1103/physrevlett.97.207802] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Indexed: 05/12/2023]
Abstract
Dynamic light scattering from orientational order fluctuations in a liquid crystalline tetrapode reveals successive, weakly first-order isotropic to uniaxial and uniaxial to biaxial nematic phase transitions. The order parameter relaxation rates exhibit temperature dependences consistent with Landau-de Gennes mean field theory. Combined with previous evidence of a second-order uniaxial-biaxial transition in a closely related tetrapode, the present study supports the existence of a nematic-nematic tricritical point in thermotropic liquid crystals.
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Sohn K, Kang SW, Ahn S, Woo M, Yang SK. Fe(0) nanoparticles for nitrate reduction: stability, reactivity, and transformation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2006; 40:5514-9. [PMID: 16999133 DOI: 10.1021/es0525758] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The pyrophoric character of zerovalent iron nanoparticles and cumbersome handling of this material has been a drawback in practical applications, despite the expectation of an enhanced reactivity. We have been interested in how the iron nanoparticles can gain stability in air without significantly sacrificing reactivity. The freshly synthesized iron nanoparticles ignited spontaneously upon exposure to air. However, when exposed slowly to air, an approximately 5 nm coating of iron oxide was formed on the surface of particles. The oxide shell did not thicken for at least two months, indicating no sign of further corrosion of iron particles. The reactivity studies on nitrate reduction showed that the freshly synthesized iron reacted at the fastest rate. After formation of the oxide shell the rate constants decreased by ca. 50% of that of fresh iron, but were still higher than that of commercial grade micro- or milli-sized iron powder. Nitrate (50 ppm/350 mL) can be recharged 6 times into a bottle containing 0.5 g of iron nanoparticles. The reduction rate of the second cycle was the fastest among the six cycles, which can be attributed to the increase of surface area and the fresh iron surfaces that were bared by the dissolution of oxidized iron species on the surface. The oxidized iron was transformed to crystalline magnetite (Fe3O4) in solution.
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Shin JC, Kim YW, Park CI, Kang SW, Yang SC. Effect of the intravesical resiniferatoxin instillation evaluated by the ice provocative urodynamic study. Spinal Cord 2006; 44:309-14. [PMID: 16186855 DOI: 10.1038/sj.sc.3101851] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN Prospective urodynamic investigation before and after intravesical resiniferatoxin instillation treatment. OBJECTIVE To evaluate the effectiveness of intravesical resiniferatoxin instillation for the treatment of neurogenic detrusor overactivity (NDO), using conventional and ice provocative urodynamic studies to monitor the activity of the unmyelinated C-fiber. SETTING Spinal Cord Injury Unit, Yonsei Rehabilitation Hospital, Seoul, Korea. METHODS A measure of 100 ml of resiniferatoxin solution, at a concentration of 100 nM diluted in 10% ethanol, was intravesically instilled into the bladder of 15 spinal cord injury patients with NDO. Conventional and ice provocative urodynamic studies were performed to evaluate the change in the involuntary detrusor activity, reflex volume, maximal bladder capacity, compliance, maximal detrusor pressure and reflex volume ratio 7 days before and 30 days after the instillation. RESULTS Before the intravesical resiniferatoxin instillation, all patients exhibited NDO in both the conventional and ice provocative urodynamic studies, with a mean reflex volume ratio of 0.45+/-0.22. There was no significant change in the maximal bladder capacity, compliance and maximal detrusor pressure at the follow-up urodynamic study, but the reflex volume ratio was significantly increased (P<0.05) after the intravesical resiniferatoxin instillation. Among the 15 patients, three (20%) showed complete and nine (60%) partial suppression of the unmyelinated C-fiber activities. CONCLUSION Intravesical resiniferatoxin instillation was partially controlled by the unmyelinated C-fiber activities, which were estimated by an ice provocative urodynamic study. Therefore, further studies on the optimal dosage and accurate indications for resiniferatoxin instillation are required.
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Bae IH, Park MJ, Yoon SH, Kang SW, Lee SS, Choi KM, Um HD. Bcl-w promotes gastric cancer cell invasion by inducing matrix metalloproteinase-2 expression via phosphoinositide 3-kinase, Akt, and Sp1. Cancer Res 2006; 66:4991-5. [PMID: 16707418 DOI: 10.1158/0008-5472.can-05-4254] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Given a previous report that Bcl-w is expressed in gastric cancer cells, particularly in those of an infiltrative morphology, we investigated whether Bcl-w expression influences the invasiveness of gastric cancer cells. To accomplish this, Bcl-w was overexpressed in adherent types of gastric adenocarcinoma cell lines, and this was found to result in an increase in their migratory and invasive potentials. These effects were not induced when Bcl-2 was overexpressed in the same cell types. Consistently, Bcl-w, but not Bcl-2, overexpression increased matrix metalloproteinase-2 (MMP-2) expression, and synthetic or natural inhibitors of MMP-2 abolished Bcl-w-induced cell invasion. Bcl-w overexpression also activated phosphoinositide 3-kinase (PI3K), Akt, and Sp1, and the blocking effects of each of these components using pharmacologic inhibitors, dominant-negative mutants, or small interfering RNA abolished the ability of Bcl-w to induce MMP-2 and cell invasion. The inhibition of PI3K/Akt signaling also prevented Sp1 activation. Overall, our data suggest that Bcl-w, which was previously shown to enhance gastric cancer cell survivability, also promotes their invasiveness by inducing MMP-2 expression via the sequential actions of PI3K, Akt, and Sp1.
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Al-Zailaie KA, Kang SW, Youngren OM, Thayananuphat A, Bakken T, Chaiseha Y, Millam JR, Proudman JA, El Halawani ME. Identification of dopamine, gonadotrophin-releasing hormone-I, and vasoactive intestinal peptide neurones activated by electrical stimulation to the medial preoptic area of the turkey hypothalamus: a potential reproductive neuroendocrine circuit. J Neuroendocrinol 2006; 18:514-25. [PMID: 16774500 DOI: 10.1111/j.1365-2826.2006.01443.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The neural and neurochemical substrates regulating reproduction in birds remain vaguely defined. The findings that electrical stimulation in the medial preoptic area (ES/MPOA) or intracerebroventricular infusion of dopamine (DA) stimulated luteinising hormone (LH) and prolactin (PRL) release in female turkeys, led to the suggestion that ES/MPOA might help to clarify the DA circuitry regulating LH and PRL. We used c-fos mRNA and tyrosine hydroxylase immunoreactivity as measured by double in situ hybridisation/immunocytochemistry (ISH/ICC) to determine which group/subgroup of DA neurones was activated following unilateral ES/MPOA. To establish that the reproductive neuroendocrine system was activated, double ISH/ICC was also conducted on c-fos/gonadotrophin-releasing hormone-I (GnRH-I) and c-fos/vasoactive intestinal peptide (VIP). Changes in circulating LH and PRL were determined by radioimmunoassay. Unilateral ES/MPOA (100 microA, right side) of anaesthetised laying turkeys for 30 min increased circulating LH and PRL levels. It also induced c-fos mRNA expression on the ipsilateral side by all GnRH-I neurones within the septopreoptic region, implying that GnRH-I neurones in this region share similar circuitry. VIP neurones within the nucleus infundibularis were the only VIP group to show c-fos mRNA expression, suggesting their involvement in ES/MPOA induced PRL release. c-fos mRNA expression was also observed in a subgroup of DA neurones in the nucleus mamillaris lateralis (ML). To our knowledge, the present study is the first to show that activation of DAergic cells in the ML is associated with the activation of GnRH-I and VIP neurones and the release of LH and PRL. It is likely that ES/MPOA activated VIP/GnRH-I neurones via activation of DA neurones in the ML, as this was the only DA subgroup that showed c-fos mRNA expression.
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