• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.281-285
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• 2002

The photophysical properties and the singlet oxygen generation efficiencies of meso-tetraphenyl-trithiasapphyrin $(S_3TPS)$ and meso-tetmkis(p-methoxy phenyl)-trithiasapphy rin ((p-MeO)-$S_3TPS$) have been investigated, utilizing steady-state and time-resolved spectroscopic methods to elucidate the possibility of their use as photosensitizers for photodynamic therapy (PDT). The observed photophysical properties were compared with those of other porphyrin-like photosensitizers in geometrical and electronic structural aspects, such as extended ${\pi}$ conjugation, structural distortion, and internal heavy atoms. The steady-state electronic absorption and fluorescence spectra were both red-shifted due to the extended ${\pi}$-conjugation. The fluorescence quantum yields were measured as very small. Even though intersystem crossing rates were expected to increase due to the increment of spin orbital coupling, the triplet quantum yields were measured as less than 0.15. Such characteristics can be ascribed to the more enhanced internal conversion rates compared with the intersystem crossing rates. Furthermore, the triplet state lifetimes were shortened to -1.0 ${\mu}s$ as expected. Therefore, the singlet oxygen quantum yields were estimated to be near zero due to the fast triplet state decay rates and the inefficient energy transfer to the oxygen molecule as well as the low triplet quantum yields. The low efficiencies of energy transfer to the oxygen molecule can be attributed to the lower oxidation potential and/or the energetically low lying triplet state. Such photophysical factors should be carefully evaluated as potential photosensitizers that have extended ${\pi}$-conjugation and heavy core atoms synthesized for red-shifted absorption and high triplet state quantum yields.

• Archives of Plastic Surgery
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• v.47 no.5
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• pp.444-450
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• 2020

Background Fingertip injuries are the most common type of traumatic injury treated at emergency departments and require prompt and adequate interventions for favorable wound survival outcomes. Hyperbaric oxygen (HBO₂) therapy is well known for its many positive effects on wound healing. We hypothesized that treatment with HBO₂ would improve the graft survival outcomes of amputated fingertip injuries treated with composite grafts. Methods This retrospective observational study included fingertip amputations that were treated between January 2013 and December 2017. A conventional group and an HBO₂ therapy group were statistically compared to evaluate the effect of HBO₂ treatment. Graft survival was categorized as either success or failure. Results Among 55 cases (digits), 34 digits were conventionally treated, while 21 digits were treated with HBO₂. No statistically significant differences were observed between the groups with regard to general characteristics. Among patients with guillotine-type injuries, the composite graft success rate was statistically significantly higher in the group that received HBO₂ therapy than in the conventional group (P=0.0337). Overall, the HBO₂ group also demonstrated a statistically significantly shorter healing time than the conventional group (P=0.0075). As such, HBO₂ treatment facilitates composite graft survival in cases of fingertip injury. Conclusions HBO₂ treatment was associated with an increased composite graft survival rate in guillotine-type fingertip injuries and reduced the time required for grafts to heal.

• Tuberculosis and Respiratory Diseases
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• v.78 no.4
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• pp.455-458
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• 2015

Excessive dynamic airway collapse (EDAC) is a disease entity of excessive reduction of the central airway diameter during exhalation, without cartilage collapse. An 80-year-old female presented with generalized edema and dyspnea at our hospital. The patient was in a state of acute decompensated heart failure due to pneumonia with respiratory failure. We accordingly managed the patient with renal replacement therapy, mechanical ventilation and antibiotics. Bronchoscopy confirmed the diagnosis of EDAC. We scheduled extubation after the improvement of pneumonia and heart condition. However, extubation failure occurred due to hypercapnic respiratory failure with poor expectoration. Her EDAC was improved in response to high flow nasal oxygen therapy (HFNOT). Subsequently, the patient was stabilized and transferred to the general ward. HFNOT, which generates physiologic positive end expiratory pressure (PEEP) effects, could be an alternative and effective management of EDAC. Further research and clinical trials are needed to demonstrate the therapeutic effect of HFNOT on EDAC.

• Toxicological Research
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• v.6 no.2
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• pp.143-157
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• 1990

Effective measure to prevent oxygen toxicity is greatly required as there increase chances to be exposed to high oxygen pressure, for example, space travel, deep sea diving and hyperbaric oxygen therapy. In the present study, in an attempt to evaluate glutathione and chlorpromazine as protective agents against oxygen toxicity, effects of the agents were tested on various toxicities (death rate, convulsion rate, time to convulsion, increase in weight of lung and brain and pathological changes in the organs) observed in rats exposed to 5 Absolute Atmosphere (ATA) of 100% oxygen for 120 minute. Glutathione reduced mortality rate and convulsion rate and also markedly suppressed the increase in lung and brain weight. The pathological changes observed in these organs were ameliorated by administration of glutathione. Chlorpromazine also reduced mortality rate but its effects appeared to be limited mainly to pulmonary toxicities. Thus glutathione seems to be more effective than chlorpromazine as a protective agent. The results obtained may support that oxygen toxicity is mediated by oxygen free radicals.

• The Journal of Korean Physical Therapy
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• v.14 no.1
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• pp.63-73
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• 2002

In order to investigate a pathogenesis of liver damage induced by skin burn, thermal injury was induced by scald burn on entirely dorsal surface in rats (total body surface area 30%) except for inhalated injury. At 5 and 24 h after scald burn, biochemical assay in skin tissue, serum and liver tissue were examined. The effects of burn injury on the levels of glutathione, lipid peroxide and on the activities of oxygen of histologic and ultrasound changes, measuring. the protein concentration in plasma, and counting the number of intravascular polymorphonuclear leukocytes. Post burn 24 h, the content of glutathione was decreased (47.50%), whereas that of lipid peroxide was increased (37.01%), and the activity of superoxide dismutase was diminished (p<0.001). Thus decreasing the capacity of oxygen free radical scavenging enzymes led to oxidative injury in skin tissue. In liver tissue, at 24 h after scald burn, both the content of glutathione and the activity of catalase were markedly decreased (p<0.01, p<0.05), thus the imbalance between free radical generating and scavenging capacities has been induced.

• Neonatal Medicine
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• v.28 no.1
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• pp.1-6
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• 2021

Persistent pulmonary hypertension of the newborn (PPHN) is a consequence of the failure of a decrease in the elevated pulmonary vascular resistance after birth. Pulmonary vasodilators, including inhaled nitric oxide (iNO), have been the mainstream of targeted therapy for PPHN, but no drugs have been proven to be effective in preterm infants with PPHN. The fetus remains hemodynamically stable despite lower arterial oxygen tension and pulmonary blood flow as compared to full-term newborns. This adaptation is due to the lower oxygen requirement and high oxygen-carrying capacity of fetal circulation. The immature lungs of preterm infants are more vulnerable to reactive oxygen species, and the response of pulmonary vascular dilatation to blood oxygen tension is blunted in preterm infants. Recently, iNO has been reported to be effective in a selected group of preterm infants, such as those with prolonged preterm rupture of membrane-oligohydramnios-pulmonary hypoplasia sequence. PPHN in preterm infants, along with maximum supportive treatment based on fetal physiology and meticulous assessment of cardiovascular function, is in dire need of new treatment guidelines, including optimal dosing strategies for pulmonary vasodilators.

• Tuberculosis and Respiratory Diseases
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• v.87 no.1
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• pp.100-114
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• 2024

Background: Long-term oxygen therapy (LTOT) improves the survival of patients with hypoxemia due to chronic respiratory diseases. The clinical outcomes of LTOT are strongly associated with patient adherence. To improve the adherence of patients, physicians have focused on the efficacy of LTOT. However, poor adherence may stem from patients' perceptions of LTOT. Herein we evaluated patients' perceptions of LTOT affecting adherence. Methods: We conducted a cross-sectional survey study using descriptive, open, and closed-ended questionnaire. Patients using oxygen therapy (OT) or requiring it but avoiding OT responded to the questionnaires at three university hospitals. Results: Seventy-nine patients responded to the questionnaires. The number of patients using home and portable OT was 69 (93%) and 37 (46.3%), respectively. Patients with good adherence were 22 (30.1%). Among patients with good adherence, 90.9% used oxygen according to physicians' prescriptions whereas only 37.3% of those with poor adherence followed physicians' prescriptions (p<0.01). The reasons for avoiding using home OT were fear of permanent use (50%), unwanted attention (40%), and lack of symptoms (40%). They avoided portable OT because of unwanted attention (39%), heaviness (31.7%), and lack of symptoms (21.6%). Conclusion: Patients on LTOT had the perception of the misunderstanding the effects of OT and of psychosocial barriers to initiate or use LTOT. Considering these findings, health professionals need to provide effective education on the purpose of LTOT to improve patient adherence to OT and provide sufficient support for the management of psychosocial barriers in patients using LTOT.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2189-2198
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• 2014

Paraquat (PQ) is a very effective and widely used herbicide that was commercially introduced in 1962. In this study, instead of using antioxidants like in the past, to inhibit the formation of PQ-induced ROS, we attempted to reduce the oxygen concentration by using non-lethal hypoxia therapy. Therefore, we studied the toxicity of PQ in vivo, analyzed the major effects of ROS on the targeted lung tissue and compared the results with the gross histological changes after the cell protective effect of non-lethal hypoxia therapy. In vivo studies demonstrated that low-concentration oxygen therapy (i.e., 10-12% oxygen) in rats administered with PQ was associated with a higher survival rate than in rats that received only PQ. In vivo non-lethal hypoxia treatment showed better survival and less lung tissue damage. Using a hypoxic/anaerobic incubator with integrated multifaceted molecular analysis, including MDA assay, glutathione assay, and SOD assay, we established an optimal, significantly reduced in vivo non-lethal hypoxia treatment by exploiting the PQ-induced cytotoxicity responses.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.3
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• pp.234-238
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• 2002

Photodynamic therapy (PDT) is based on a photochemical reaction which is initiated by light activation of a photosensitizer. The photosensitizer accumulates more in tumor tissues than in normal tissues and is activated with specific wavelength of light, usually laser. The photochemical reaction produces highly reactive oxygen products causing cytotoxiciy and vascular shutdown to the tumor. The advantages of PDT are its relative selective tumor destruction and tissue healing by regeneration, which can maintain important structures with very good functional and esthetic results. Therefore, PDT is considered as an alternative modality for cancers of the head and neck. In this article, we will report three cases of photodynamic therapy for treatment of oral leukoplakia, squamous cell carcinoma, and basal cell carcinoma of head and neck. It was observed that premalignant and malignant lesions responded well to the photodynamic therapy with Aminolevulinic acid (ALA) and $Foscan^{(R)}$. Photodynamic therapy can be considered as a new treatment method for the premalignant and malignant tumors in Oral and Maxillofacial Surgery.

• Journal of Digital Convergence
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• v.12 no.7
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• pp.349-356
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• 2014

The present study was aimed to investigate the effects of the application of pulsed electromagnetic fields on the blood components associated hyperlipidemia, antioxidant enzymes and reactive oxygen. The subjects were divided into three groups: General Diet, High fat Diet, High fat diet and pulsed electromagnetic fields. Pulsed electromagnetic field was applied with pulsed electromagnetic energy therapy equipment. The Glucose, free fatty acids, triglycerides, cholesterol and insulin was used to measure hyperlipidemia-related blood components, and the GSH, GRD, XO and MDA was used to measure antioxidant enzymes and reactive oxygen. The applied pulsed electromagnetic field has improved the concentrations of blood components and increasing GSH and GRD, that were decreased due to a high-fat diet and by reducing the increased MDA and XO to a level of general diet group. Therefore, the applied pulsed electromagnetic field can be the effective treatment for changes in the blood composition of hyperlipidemic rats, enhancement of antioxidative activity and the inhibition of reactive oxygen.