• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• 제33권3호
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• pp.166-171
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• 2022

Background and Objectives Vocal fold (VF) scar is known to be the most common cause of dysphonia after laryngeal microsurgery (LMS). Steroids reduce postoperative scar formation by inhibiting inflammation and collagen deposition. However, the clinical evidence of whether steroids are helpful in reducing VF scar formation after LMS is still lacking. The purpose of this study is to determine whether intralesional VF steroid injection after LMS helps to reduce postoperative scar formation and voice quality. Materials and Method This study was conducted on 80 patients who underwent LMS for VF polyp, Reinke's edema, and leukoplakia. Among them, 40 patients who underwent VF steroid injection after LMS were set as the injection group, and patients who had similar sex, age, and lesion size and who underwent LMS alone were set as the control group. In each group, stroboscopy, multi-dimensional voice program, Aerophone II, and voice handicap index (VHI) were performed before and 1 month after surgery, and the results were statistically analyzed. Results There were no statistically significant differences in the distribution of sex, age, symptom duration, occupation and smoking status between each group. Both groups consisted of VF polyp (n=21), Reinke's edema (n=11), and leukoplakia (n=9). On stroboscopy, the lesion disappeared after surgery, and the amplitude and mucosal wave were symmetrical on both sides of the VFs in all patients. Acoustic parameters and VHI significantly improved after surgery in all patients. However, there was no significant difference between the injection and control group in most of the results. Conclusion There was no significant difference in the results of stroboscopy, acoustic, aerodynamic, and subjective evaluation before and after surgery in the injection group and the control group.

• Tuberculosis and Respiratory Diseases
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• 제52권6호
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• pp.616-626
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• 2002

Background : The present study was performed to further improve our understanding of molecular mechanisms involved in the activation of NFkB, a major transcriptional factor involved in the inflammatory response in the lung, by particulate matter in lung epithelial cells with an aerodynamic diameter of less than $2.5{\mu}m$(PM2.5). Materials and Methods : Immediate production of reactive oxygen species (ROS) and nitrogen species (RNS), with the PM2.5 induced expression of inducible nitric oxide synthase (iNOS), $I{\kappa}B$ degradation and $NF{\kappa}B$-dependent transcriptional activity, in 549 cells, were monitored. Addition, we also examined the effect of the iNOS inhibitor, L-N6-(1-iminoethyl) lysine hydrochloride (L-NIL), on the PM2.5-induced $NF{\kappa}B$ activation in A549 cells. Results : The rapid degradation of $I{\kappa}B$ and the increase of transcriptional activity of the $NF{\kappa}B$-dependent promotor were observed in A549 cells exposed to PM2.5. The immediate production of ROS in response to PM2.5 in A549 cells was not clearly detected, although immediate responses were observed in RAW264.7 cells. A 549 cells, cultured in the presence of PM2.5, produced an increase in NO, which was noticeably significant after 15 min of exposure with the expression of iNOS mRNA. The addition of L-NIL, an iNOS inhibitor, significantly inhibited the PM2.5-induced $I{\kappa}B$ degradation and the increase of the $NF{\kappa}B$-dependent transcriptional activity. Conclusion : These results suggest that PM2.5 stimulates the immediate production of RNS, leading to the activation of $NF{\kappa}B$ in the pulmonary epithelium.

• Journal of Bio-Environment Control
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• 제15권4호
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• pp.296-305
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• 2006

The heterogeneity of crop transpiration is important to clearly understand the microclimate mechanisms and to efficiently handle the water resource in greenhouses. A computational fluid dynamic program (Fluent CFD version 6.2) was developed to study the internal climate and crop transpiration distributions of greenhouses. Additionally, the global solar radiation model and a crop heat exchange model were programmed together. Those models programmed using $C^{++}$ software were connected to the CFD main module using the user define function (UDF) technology. For the developed CFD validity, a field experiment was conducted at a $17{\times}6 m^2$ plastic-covered mechanically ventilated single-span greenhouse located at Pusan in Korea. The CFD internal distributions of air temperature, relative humidity, and air velocity at 1m height were validated against the experimental results. The CFD computed results were in close agreement with the measured distributions of the air temperature, relative humidity, and air velocity along the greenhouse. The averaged errors of their CFD computed results were 2.2%,2.1%, and 7.7%, respectively.