• Bulletin of the Korean Chemical Society
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• 제23권2호
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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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• 제47권5호
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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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• 제78권4호
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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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• 제6권2호
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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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• 제14권1호
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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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• 제28권1호
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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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• 제87권1호
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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.

• 한국산학기술학회논문지
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• 제15권4호
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• pp.2189-2198
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• 2014

본 연구는 제초제 음독 중에서 가장 치명률이 높은 파라쿼트 중독의 독성 감소를 위하여 파라쿼트 독성 기전으로 알려진 파라쿼트 유도성 활성산소종을 감소시키기 위해 기존의 항산화제들 치료제와는 달리, 사전에 산소 농도를 줄여서 파라쿼트에 의한 활성 산소종 발생 자체를 줄이는 저농도 산소요법의 유용성을 연구하였다. 이를 위해 백서를 활용하여 생존률 및 파라쿼트에 의한 활성 산소종의 영향을 가장 빠르고 많이 받는 폐조직의 육안적 조직학적 변화를 비교 분석함으로써 세포 독성 상황에서 저농도 산소요법의 효과를 분석하였다. 그 결과 저농도 산소요법을 처리한 군에서 유의한 생존률 증가와 함께 H&E Stain결과에서는 염증세포 증가 및 Aveolar space에 부종 소견이 저농도 산소요법을 함께 시행한 군에서 완화된 소견을 확인할 수 있었다. 또한 파라쿼트의 독성기전의 핵심인 산화스트레스발생 분석을 시행한 결과, MDA assay, Glutathione assay 및 SOD Assay모두에서 파라쿼트는 산화스트레스를 증가하지만 파라쿼트와 함께 저농도 산소요법을 처리한 경우 산화 스트레스가 감소함을 증명하였다. 이를 통해 본 연구는 임상에서 파라쿼트 중독에 대한 새로운 치료 대안으로서의 기초 연구로서 활용이 기대된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제28권3호
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• pp.234-238
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• 2002

구강악안면외과 영역의 전암병소와 종양의 치료를 위하여 국소적으로 ALA, 전신적으로 Forscan의 광감각제를 도포하거나 주입하여 기능적, 심미적으로 좋은 결과를 얻을 수 있었다. 아직 장기적인 추적조사가 요구되지만 광역학 요법은 기존의 수술법, 항암요법, 방사선치료와 함께 종양의 새로운 치료방법으로 이용될 수 있을 것으로 사료된다.

• 디지털융복합연구
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• 제12권7호
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• pp.349-356
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• 2014

본 연구는 맥동전자장이 고지혈증 관련 혈액 성분, 항산화 효소와 활성 산소에 어떠한 영향을 미치는 지를 관찰하기 위하여 실시하였다. 실험군은 정상식이군, 고지방식이군과 고지방식이-맥동전자장 적용군의 3군으로 나누었다. 맥동 전자장은 맥동 전자장 에너지 치료기를 이용하였다. 혈액 성분의 검사 항목은 혈당, 유리지방산, 중성지방 및 콜레스테롤, 인슐린이고, 항산화 효소와 활성 산소의 검사는 글루타치온, 글루타치온 환원효소, 크산틴, 과산화지질을 측정하였다. 그 결과 맥동전자장 적용은 혈액 구성성분과 GSH와 GRD를 고지장식이 수준에서 정상식이 수준으로 상승시켰으며, XO와 MDA는 고지방식이 수준에서 정상 식이 수준으로 낮추어 주는 개선효과를 나타내었다. 그러므로 맥동전자장의 적용은 고지혈증 흰쥐의 혈액성분의 변화, 항산화 효소의 증가, 활성 산화의 억제에 효과적인 치료 방법이라 할 수 있다.