• Clinical and Experimental Pediatrics
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• v.46 no.10
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• pp.989-995
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• 2003

Purpose : Dexamethasone is frequently administered to prevent or treat chronic lung disease in human neonates who are also prone to hypoxic-ischemic(HI) insults. Recently, meta-analysis of the follow-up studies reveals a significantly increased odd ratio for the occurrence of cerebral palsy or an abnormal neurologic outcome, and there is conflicting evidence regarding the impact of dexamethasone exposure on HI brain injury. This study was conducted to explore the effect of post-HI dexamethasone administration on neuronal injury in neonatal rats. Methods : HI was produced in seven-day-old rats by right carotid artery ligation followed by two hours of 8% oxygen exposure. At the end of HI, the animals were injected intraperitoneally either with dexamethasone(0.5 mg/kg) or saline. Neuronal injury was assessed seven days after the HI by the area of infarction, TUNEL reactivity, Bcl-2 and Bax expression in brain. Results : Post-insult dexamethasone administration resulted in reduction of weight gain and a higher mortality rate during seven days after HI. Dexamethasone treatment revealed no effect on the size of brain infarction induced by HI. Bax protein expression increased in dexamethasone treated brain but Bcl-2 protein expression and TUNEL reactivity revealed no significant differences between dexamethasone treated and non treated brain. Increased Bax protein expression suggest upregulation of the apoptosis by dexamethasone. Conclusion : The result suggests the adverse role of Post-HI administration of dexamethasone in neonatal HI.

• Neonatal Medicine
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• v.16 no.2
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• pp.146-153
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• 2009

Purpose: The aim of this study is to investigate the current use of dexamethasone rescue therapy (DRT) for bronchopulmonary dysplasia (BPD). Methods: This is a retrospective study of 251 BPD patients managed in the neonatal intensive care units at Seoul National University Childrens Hospital and Seoul National University Bundang Hospital between March 2004 and August 2008. The demographic data and clinical characteristics of the mothers and infants were analyzed. The infants were compared based on DRT responsiveness. The DRT complications were investigated. Results: Ninety-three patients (37.1%) were classified with severe BPD, DRT was only given to patients with severe BPD. Dexamethasone was administered to 24 patients (9.6%) whose respiratory status had precluded extubation, which indicated that conventional BPD management had failed. Fourteen patients (58.3%) who received DRT were responsive. DRT non-responders required more oxygenation and more complicated with pulmonary arterial hypertension (PAH). Responder had shorter length's of hospitalization and lower mortality rates. High dose dexamethasone was no more effective in weaning neonates from the ventilatior than low dose dexamethasone. Sepsis was the most common complication of DRT. Conclusion: DRT is a valuable treatment for severe BPD ahead of PAH development. DRT should not be performed in BPD patients with PAH due to the possibility of complications.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.1
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• pp.61-67
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• 2008

Objective: This study was attempted to look at the effect of dexamethasone on the luteolysis of corpus luteum in rats by immunohistochemical study. Methods: Counting with an optical microscope was conducted to make a comparison on difference in luteolysis and penetration of macrophage into three groups: control group of 30 female rats at 8 weeks of age, dexamethasone 0.1 mg administered group, and dexamethasone 1mg administered group. Results: As a result of TUNEL immunostaining, the percentage of luteolysis was significantly reduced in both dexamethasone 0.1 mg administered group and 1 mg administered group, and after ED1 immunostaining, macrophage invasion was reduced in dexamethasone 1 mg administered group. As a consequence of ED1 immunostaining, the immune response of macrophage was much decreased in dexamethasone 1 mg administered group than control group. Conclusion: Dexamethasone works on luteal cell, so it can suppress apoptosis. It can suppress luteolysis by suppression macrophage invasion into corpus luteum or suppress macrophage activation in corpus luteum.

• Journal of Veterinary Clinics
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• v.24 no.4
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• pp.503-508
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• 2007

Although canine facial nerve paralysis(FNP) occurs similarly in humans, there is no properly recognized therapy using Western medicine for idiopathic causes. To elucidate therapeutic measures by acupuncture(AP) on canine FNP, we examined the therapeutic effect of injection-AP on the artificially induced canine FNP. Twelve dogs on artificially induced canine FNP were divided into a control group(4 dogs), an experimental dexamethasone-treated group(dexamethasone group, 4 dogs) and an experimental bee venom-treated group(apitoxin group, 4 dogs). Saline (1 ml) was intramuscularly injected into the head muscle after the induction of FNP in the control group. On the other hand, injection-AP with dexamethasone was performed on such acupoints as LI04, LI20, ST02, ST07, TH17, SI18, GB03 and GB34, twice per week after induction of FNP in the dexamethasone group. In addition, injection-AP with $100{\mu}g$ of apitoxin was performed on the same acupoints as the dexamethasone group twice per week after the induction of FNP in the apitoxin group, respectively. The changes of the clinical symptoms of FNP with each treatment during the experimental period were recorded by using clinical scores, respectively. The changes of serum creatine kinase(CK) activities along with each treatment were determined using an autoanalyzer. The significant differences of clinical scores were detected on day 14(p<0.05) in the apitoxin and dexamethasone groups, compared with those in the control group, respectively. However, significant difference was not detected between the apitoxin and dexamethasone groups. Significant differences of serum CK activities were detected on day 7(p<0.05) and day 14(p<0.05) in the dexamethasone and apitoxin groups, compared with those in the control group, respectively. However, significant difference was not detected between the dexamethasone and apitoxin groups. In condition, injection-APs with apitoxin and dexamethasone were all effective for treatment of canine FNP and the therapeutic effect by injection-AP with apitoxin was similar to that of injection-AP with dexamethasone.

• Clinical and Experimental Pediatrics
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• v.46 no.4
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• pp.335-339
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• 2003

Purpose : Surfactant protein A(SP-A) is involved in surfactant physiology and structure, and plays a major role in innate host defense and inflammatory processes in the lung. Steroid therapy is widely used for mothers who threaten to deliver prematurely and also used commonly in the management of preterm infants with chronic lung disease. Two SP-A genes(SP-A1, SP-A2) and several alleles have been characterized for each SP-A gene in human. Preliminary evidence indicates that differences may exist among alleles in response to Dexamethasone(Dexa) and that the SP-A 3'UTR plays a role in this process. We studied whether 3'UTR-mediated differences exist among the most frequently found SP-A alleles in response to Dexa. Methods : Constructs containing the 3'UTR from eight different SP-A alleles were made using luciferase as a the reporter gene. These constructs were driven by the SV40 promotor and were transfected along with a transfection control vector in H441 cells that express SP-A. The activity of the reporter gene in the presence or absence of Dexa(100 nM) treatment was measured. All the experiments for the eight SP-A alleles studied, were performed in triplicate and repeated five times. The results were normalized to the transfection control. Results : Expression of alleles of 6A3, 6A, 1A were significantly decreased in response to Dexa. Conclusion : Three UTR mediated differences exist among human SP-A variants both in the basal expression and in response to Dexa. These genotype-dependent differences may point to a need for a careful consideration of individual use of steroid treatment in the prematurely born infant.

• Journal of Veterinary Clinics
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• v.23 no.1
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• pp.69-71
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• 2006

An 11-year-old, Shorthorn cow, reared near Gort Co. Galway, Ireland, needed assistance to calve. The cow became a downer on that day postpartum (pp). Injection-acupuncture with dexamethasone was used at lumbo-sacral space, GB30, ST36, GB31, BL40, ST40 and ST41. In addition, modified moxibustion was received at session 1. At session 2, the cow could not stand. At session 3, the cow tried to stand twice by herself but fell down again each time. However, she stood up with slight help on 10 days pp. The present patient was a case with downer cow syndrome which showed improvement of clinical symptoms by injection-acupuncture with dexamethasone plus modified moxibustion.

• Tuberculosis and Respiratory Diseases
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• v.54 no.4
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• pp.439-448
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• 2003

Background : Surfactant protein B(SP-B) and surfactant protein C(SP-C) are important in accelerating surface spreading of surfactant phospholipid. The glucocorticoids accelerate the morphologic differentiation of epithelial cells into type II cells and increase the rate of phosphatidylcholine synthesis. The hydrophobic surfactant protein has been shown to be upregulated by glucocorticoids in vitro, however, its regulation in vivo is not well established. Methods : The authors investigated the effects of glucocorticoid on the accumulation of mRNA encoding SP-B and SP-C protein content of the lung. Adult rats were given different doses of subcutaneous dexamethasone and sacrificed at 24 hours and 1 week. SP-B and SP-C mRNA were measured by a filter hybridization method. Results : 1) The accumulation of SP-B mRNA at 24 hours after 0.2 mg/kg dexamethasone treatment was increased by 23.7%. 2) The accumulation of SP-B mRNA at 1 week after 2 mg/kg dexamethasone treatment was significantly increased by 96.6%(P<0.001). 3) The accumulation of SP-C mRNA at 24 hours after 0.2 mg/kg dexamethasone treatment was significantly increased by 42.7%(P<0.01). 4) The accumulation of SP-C mRNA at 1 week after 2 mg/kg dexamethasone treatment was significantly increased by 60.0% (P<0.01). Conclusion : The authors concluded that dexamethasone treatment in vivo resulted in increased levels of SP-B mRNA and SP-C mRNA. These results suggested that dexamethasone stimulates the synthesis of hydrophobic proteins associated with surfactant.

• Journal of the Korean Chemical Society
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• v.50 no.6
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• pp.464-470
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• 2006

the coricosteroid drug dexamethasone is an efficacious antiinflammatory drug, it is difficult to formulate in an injectable formulation due to its poor aqueous solubility. A lipid-based nanosphere formulation containing dexamethasone was designed for solubilization of the drug in aqueous solution and sustained release of the drug from the nanosphere. The lipid nanospheres, composed of phospholipid, cholesterol and cationic lipid, were prepared by self emulsification-solvent diffusion method followed by diafiltration. Physicochemical characteristics such as mean particle diameter, zeta potential and drug loading efficiency of the lipid nanospheres were investigated according to the variation of either the kind of lipid or the lipid composition. The lipid nanospheres had a mean diameter 80-120 nm and dexamethasone loading efficiency of greater than 80%. The drug loading efficiency increased with the increase of the length of aliphatic chain attached to the phospholipid. However, the drug loading efficiency was inversely proportional to the increase of cholesterol content in the lipid composition. The lipid nanosphere could not be prepared without the use of cationic lipid and the drug loading efficiency was proportional to the increase of cationic lipid content. The lipid nanospheres containing dexamethasone are a promising novel drug carrier for an injectable formulation of the poorly water-soluble drugs.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.418-423
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• 2017

An analytical method for the determination of dexamethasone (DM) in bovine milk samples was developed and validated using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Milk samples were extracted by the liquid-liquid extraction based on acetonitrile. The chromatographic separation was achieved on a reverse phase $C_{18}$ column with gradient elution using a mobile phase of 0.1% formic acid in 95% acetonitrile. The procedure was validated according to the Ministry of Food and Drug Safety guideline determining accuracy, precision, limit of detection (LOD), and limit of quantification (LOQ). Mean recoveries of DM from spiked milk samples (25, 125, and 1,250 ng/mL) were 98.9-109.6%, and the relative standard deviation was between 1.7 and 4.4%. Linearity in concentration range of 12.5-1,250 ng/mL was obtained with the correlation coefficient ($r^2$) of 0.9997. LOD and LOQ for the investigated DM were 0.15 and 0.5 ng/mL depending on milk samples, respectively. This method was reliable, sensitive, economical and suitable for routine monitoring of DM residues in bovine milk.

• Journal of Veterinary Clinics
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• v.23 no.1
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• pp.6-8
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• 2006

One male Arabian horse, 13-year-old reared in Galway, Ireland, was diagnosed as laminitis. Hemo-acupuncture at TH01, SI01 and ST45 was used. Injection acupuncture with dexamethasone was also applied at the same acupoints after homo-acupuncture twice a week. Bee-venom was injected into GV01 at session 2. After session 3, the patient showed almost normal walking.