• Tuberculosis and Respiratory Diseases
• /
• v.58 no.3
• /
• pp.276-284
• /
• 2005

Backgraound : There have been many reports on the pathogenesis of sepsis-induced acute respiratory distress syndrome(ARDS) but, the precise mechanism has not been elucidated. This study examined the protective effect of an inhibition of platelet activating factor(PAF) remodeling and the adhesion molecule on the oxidative stress of the lungs in rats with an endotoxin induced acute lung injury(ALI). Methods : ALI was induced in Sprague-Dawley rats by instilling an E-coli endotoxin into the trachea. Ketotifen and fucoidan were used respectively to inhibit PAF remodeling and adhesion molecule. The lung leak index, lung myeloperoxidase(MPO) activity, bronchoalveolar lavage(BAL) fluid neutrophil count and lyso PAF acetyltransferase activity(AT), were measured and an ultrastructural study and cytochemical electron microscopy were performed. Results : The lung leak index, lung MPO activity, BAL fluid neutrophil count and lyso PAF AT activity was higher in the endotoxin-treated rats. In addition, severe destruction of the pulmonary architecture and increased hydrogen peroxide production were identified. These changes were reversed by ketotifen. However, fucoidan did not appear to have any protective effects. Conclusion : The inhibition of PAF remodeling appeared to be effective in decreasing the endotoxin-induced ALI. In addition, this effect might be derived from the inhibition of neutrophilic oxidative stress. However, the inhibition of the adhesion molecules by fucoidan appeared to be ineffective in decreasing the endotoxin-induced ALI.

• Tuberculosis and Respiratory Diseases
• /
• v.46 no.5
• /
• pp.628-635
• /
• 1999

Background : Maximal expiratory flow rate is determined by the size of airway, elastic recoil pressure and the collapsibility of airway in the lung. The obstruction of expiratory flow is one of the major functional impairments of emphysema, which represents COPD. Nevertheless, expiratory narrowing of upper airway may be recruited as a mechanism for minimizing airway collapse, and maintaining lung volume and hyperinflation by an endogenous positive end-expiratory pressure in patients with airflow obstruction. We investigated the physiologic role of trachea in respiration in emphysema. Method : We included 20 patients diagnosed as emphysema by radiologic and physiologic criteria from January to August in 1997 at Seoul Municipal Boramae Hospital. Chest roentgenogram, high resolution computed tomography(HRCT), and pulmonary function tests including arterial blood gas analysis and body plethysmography were taken from each patient. Cross-sectional area of trachea was measured according to the respiratory cycle on the level of aortic arch by HRCT and calibrated with body surface area. We compared this corrected area with such parameters of pulmonary function tests as $PaCO_2$, $PaO_2$, airway resistance, lung compliance and so on. Results : Expiratory cross-sectional area of trachea had significant correlation with $PaCO_2$ (r=-0.61, p<0.05), $PaO_2$ (r=0.6, p<0.05), and minute ventilation (r=0.73, p<0.05), but inspiratory cross-sectional area did not (r=-0.22, p>0.05 with $PaCO_2$, r=0.26, p>0.05 with $PaO_2$, and r=0.44, p>0.05 with minute ventilation). Minute ventilation had significant correlation with tidal volume (r=0.45, p<0.05), but it had no significant correlation with respiratory frequency (r=-0.31, p>0.05). Cross-sectional area of trachea had no significant correlation with other parameters of pulmonary function including $FEV_1$, FVC, $FEV_1$/FVC, peak expiratory flow, residual volume, diffusing capacity, airway resistance, and lung compliance, whether the area was expiratory or inspiratory. Conclusion : Cross-sectional area of trachea narrowed during expiration in emphysema, and its expiratory area had significant correlation with $PaCO_2$, $PaO_2$, and minute ventilation.

• Tuberculosis and Respiratory Diseases
• /
• v.46 no.5
• /
• pp.636-644
• /
• 1999

Background : Tumor necrosis factor(TNF) has been considered as an important candidate for cancer gene therapy based on its potent anti-tumor activity. The mechanisms of TNF cytotoxicity are not clearly understood and some has reported that reactive oxygen species(ROS) might be associated with them, but there is controversy about antioxidant effect on TNF cytotoxicity. This study was designed to compare the TNF cytotoxicity after antioxidant pretreatment with that of control to evaluate the role of ROS in the mechanism of TNF cytotoxicity. Method : We compared the TNF cytotoxicies to WEHI164(murine fibrosarcoma cell line) and ME180(human cervix cancer cell line) after antioxidant pretreatment with those of control by MIT(dimethylthiazolyl-diphenyltetrazolium bromide) assay. Results : In the control group, the TNF cytotoxicities were $92.2{\pm}2.8%$(WEHI164) and $59.9{\pm}7.0%$(MEl80). In the TMTU(tetramethyl thiourea) pretreatment group, those were $91.4{\pm}3.7%$ and $74.6{\pm}7.0%$. In the PMZ(promethazine) pretreatment group, those were $90.2{\pm}2.5%$ and $62.5{\pm}5.7%$. In the BHT(butylated hydroxytoluene) pretreatment group, those were $93.2{\pm}1.3%$ and $66.3{\pm}6.1%$. So there was no reduction in TNF cytotoxicity after antioxidants pretreatment. Conclusion : The ROS may not have major role in the mechanisms of TNF cytotoxicity.

• Neonatal Medicine
• /
• v.17 no.1
• /
• pp.64-74
• /
• 2010

Purpose : The aim of this study was to determine the risk factors, clinical characteristics and prognosis for the development of periventricular leukomalacia (PVL) in preterm infants according to the extent and site of the PVL. Methods : The medical records of infants (under 36 weeks of gestational age) delivered from January 1999 to December 2008 were reviewed. Twenty-five preterm infants with were PVL were diagnosed by brain magnetic resonance imaging (MRI) and an addition 50preterm infants with no brain lesions were enrolled in this study. The perinatal and neonatal risk factors for the development of PVL was determine in these infants. Mental and Psychomotor Developmental Indices (MDI, PDI) were assessed by a clinical psychologist using the Bayley Scales of Infant Development II. We compared the differences of the clinical characteristics and prognosis according to brain MRI findings. Results : Maternal fever, young maternal age, extended oxygen use, hypotension within the first week of birth, use of inotropics within the first week of birth, and respiratory distress syndrome were the risk factors associated with PVL (P <0.05). In the multivariate analysis, maternal fever and extended oxygen use were statistically significant independent risk factors (P <0.05). The mean MDI and PDI scores of the PVL group (74.4$\pm$ 27.8 and 58.0$\pm$17.7) were significantly lower than those of the control group (103.5$\pm$8.9 and 101.7$\pm$16.1, P <0.05). Conclusion : Maternal fever and extended oxygen use were independent risk factors for PVL. We should pay attention to infants who had the risk factors and follow them up closely by brain imaging study and Bayley Scales of Infant Development II.

• Clinical and Experimental Pediatrics
• /
• v.53 no.3
• /
• pp.349-357
• /
• 2010

Purpose : Transient tachypnea of the newborn (TTN) is usually benign and improves within 72 hours. However, it can also progress to prolonged tachypnea over 72 hours, profound hypoxemia, respiratory failure, and even death. The aim of this study is to find predictable risk factors and describe the clinical courses and outcomes of prolonged TTN (PTTN). Methods : The medical records of 107 newborns, >$35^{+0}$ weeks of gestational age with TTN, who were admitted to the NICU at Seoul Asan Medical Center from January 2001 to September 2007 were reviewed. They were divided into 2 groups based on duration of tachypnea. PTTN was defined as tachypnea ${\geq}72$ hours of age, and simple TTN (STTN) as tachypnea <72 hours of age. We randomly selected 126 healthy-term newborns as controls. We evaluated neonatal and maternal demographic findings, and various clinical factors. Results : Fifty-five infants (51%) with total TTN were PTTN. PTTN infants had grunting, tachypnea >90/min, $FiO_2$ >0.4, and required ventilator care more frequently than STTN infants. PTTN had lower level of serum total protein and albumin than STTN. The independent predictable risk factors for PTTN were grunting, maximal respiration rate >90/min, and $FiO_2$ >0.4 within 6 hours of life. Conclusion : When a newborn has grunting, respiration rate >90/min, and oxygen requirement >0.4 of $FiO_2$ within 6 hours of life, the infant is at high risk of having persistent tachypnea ${\geq}72$ hours. We need further study to find the way to reduce PTTN.

• Analytical Science and Technology
• /
• v.27 no.5
• /
• pp.234-242
• /
• 2014

Imicyafos which is a nematicide for controlling root-knot nematodes has been registered in the Republic of Korea in 2012, and the maximum residue limits of imicyafos are set to watermelon and korean melon as each 0.05 mg/kg. Extremely reliable and sensitive analytical method is required for ensuring food safety on imicyafos residues in agricultural commodities. Imicyafos residues in samples were extracted with acetone, partitioned with hexane and dichloromethane, and then purified with florisil. The purified samples were analyzed by HPLC-UVD and confirmed with LC-MS. Linear range was between 0.1~5 mg/kg with the correlation coefficient ($r^2$) 0.99997. Average recoveries of imicyafos ranged from 77.0 to 115.4% at the spiked levels of 0.02 and 0.05 mg/kg with the relative standard deviations of 2.2~9.6%. Limit of detection and quantification were 0.005 and 0.02 mg/kg, respectively. An inter-laboratory study was conducted to validate the determination method in depth, and the results were satisfactory. All of the validation results revealed that the developed analytical method in this study is relevant for imicyafos determination in agricultural commodities and will be used as an official analytical method.

• Tuberculosis and Respiratory Diseases
• /
• v.53 no.6
• /
• pp.612-618
• /
• 2002

Background : Bronchoscopy is an important diagnostic and a therapeutic tool in chest medicine. However, most patients feel that a bronchoscopy is an unpleasant procedure, and it is important to sedate the patients appropriately, particularly where repetitive examinations are required. Midazolam is a sedative drug with amnestic qualities and a rapid 2 hour half-life. This study have attempted to determine the safety, appropriate dosage, and the effect of midazolam premedication in patients who underwent a bronchoscopy. Methods : One hundred and eighty consecutive patients undergoing bronchoscopy were enrolled in this study. The patients received a midzolam doses of 0.03 mg/kg, 0.06 mg/kg, or a placebo. An additional dose of lidocaine, the total number of coughs, and the duration of the procedures were recorded with monitoring the the blood pressure, heart rate, and oxygen saturation. The level of satisfaction was assessed by the patient, bronchoscopist, and the nurse. Results : The blood pressure, pulse rates, oxygen saturation, number of coughs, lidocaine dose, and procedure time in the 3 groups were similar. There was a trend for the midazolam 0.03 mg/kg group to satisfy bronchoscopists more than the other two groups. The nurses' acceptability was lower in the midazolam 0.06 mg/kg group than the other groups. The patients' acceptablity was greater in both the midazolam 0.03 mg/kg and 0.06 mg/kg groups than in the control group. Conclusion : Sedation with low doses of intravenous midazolam is a safe technique for fiberoptic bronchoscopy with a low morbidity and high acceptable to patients and bronchoscopists.

• Korean Journal of Food Science and Technology
• /
• v.33 no.3
• /
• pp.378-383
• /
• 2001

Formation of superoxide anion $O_2\bar{{\bullet}}$ in the autoxidation of L-ascorbic acid (AsA) in the presence of heavy metal ions were determined. The generation of $O_2\bar{{\bullet}}$ was studied by using superoxide dismutase (SOD) in aqueous and buffer solution, and using nitro bule tetrazolium (NBT) in methanol solution. The remaining amount of AsA was significantly higher in the presence of SOD than in its absence. It suggested that SOD stabilizes AsA in aqueous and buffer solution because of scavenging $O_2\bar{{\bullet}}$ formed during the autoxidation reaction of AsA in the presence of heavy metal ions. NBT has an absorption maximum at about 560 nm in methanol solution. The absorbance at 560 nm increased during the oxidation of AsA, suggested the formation of $O_2\bar{{\bullet}}$in methanol solution. Thus, the formation of $O_2\bar{{\bullet}}$ was confirmed during the autoxidation of AsA not only in aqueous solution but also in methanol solution in the presence heavy metal ions.

• Tuberculosis and Respiratory Diseases
• /
• v.50 no.4
• /
• pp.415-425
• /
• 2001

Background : The correlation between the high resolution computed tomography(HRCT) emphysema score and the physiologic parameters including resting and exercise pulmonary function test was investigated in 14 patients($60.6{\pm}10.3$ years) with pulmonary emphysema. Methods : The patients underwent a HRCT, a resting pulmonary function test, and incremental exercise testing(cycle ergometer, 10 W/min). Computed tomography scans were obtained on a GE highlight at 10 mm intervals using 10 mm collimation, from the apex to the base after a full inspiration. The emphysema scores were determined by a CT program 'Density mask' outlining the areas with attenuation values less than -900 HU, indicating the emphysema areas, and providing an overall percentage of lung involvement by emphysema. Results : Among the resting PFT parameters, only the diffusing capacity(r=-0.75) and $PaO_2$ (r=-0.66) correlated with the emphysema score(p<0.05). Among the exercise test parameters, the emphysema score correlated significantly with the maximum power(r=-0.74), maximum oxygen consumption(r=-0.68), anaerobic threshold(V-slope method: r=-0.69), maximal $O_2$-pulse(r=-0.73), and the physiologic dead space ratio at the maximum workload(r=-0.80)(p<0.01). Conclusion: We could find that exercise testing parameters showed a much better correlation with the HRCT emphysema score, which is known to have a good correlation with the pathologic severity than the resting PIT parameters. Therefore it is suggested that exercise testing is superior to resting PIT for estimating in the estimation of the physiologic disturbance in emphysema patients.

• Applied Chemistry for Engineering
• /
• v.23 no.2
• /
• pp.183-189
• /
• 2012

In this study, the cellular protective effect and antioxidative property of peanut sprout root extracts were investigated. Cellular protective effects of peanut sprout root extracts on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethyl acetate fraction of extracts exhibited a cellular protective effect in a concentration dependent manner. Particularly, the aglycone fraction of extracts showed prominent cellular protective effects in a concentration range (5~50 ${\mu}g/mL$). They are more effective than that of (+)-${\alpha}$-tocopherol, known as a lipid peroxidation chain blocker. Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of peanut sprout root extracts on ROS generated in $Fe^{3+}$-EDTA/$H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction of extracts ($OSC_{50}$; 1.59 ${\mu}g/mL$) showed a similar ROS scavenging activity compare with that of L-ascorbic acid (1.50 ${\mu}g/mL$), known as a strong antioxidant. On the other hand, the order of free radical (1,1-diphenyl-2-picrylhydraxyl, DPPH) scavenging activity ($FSC_{50}$) was (+)-${\alpha}$-tocopherol > 80% MeOH extract > aglycone fraction > ethyl acetate fraction. These results indicate that peanut sprout root extracts can function as an antioxidant in biological systems, particularly skin exposed to solar UV radiation by scavenging $^1O_2$ and other ROS, and to protect cellular membranes against ROS.