The effect of periodontitis on recipient outcomes after kidney transplantation

민현진,박정수,Yang Jaeseok,Yang Jihyun,Oh Se Won,조상경,조원용,권준교,정철웅,설양조,박신영,김명규 대한신장학회 2022 Kidney Research and Clinical Practice Vol.41 No.1

Background: Recent several reports have demonstrated that periodontitis is prevalent and adversely affects the survival in patients with chronic kidney disease (CKD) or end-stage kidney disease. However, its impact on transplant outcomes remains uncertain.Methods: This retrospective cohort study included 136 and 167 patients, respectively, who underwent living donor kidney transplantation (KT) at Seoul National University Hospital from July 2012 to August 2016 and Korea University Hospital from April 2008 to October 2018. We divided patients into three groups according to stages of periodontitis based on a new classification system. Results: Patients with severe periodontitis were older, had a higher prevalence of diabetes, a higher body mass index and C-reactive protein level, a lower cardiac output, and were more likely to be smokers, indicating its association with chronic systemic inflammation. After KT, stage IV periodontitis was independently associated with a lower incidence of acute T cell-mediated rejection, suggesting the possible effect of periodontitis on immune function. However, 1-year and 3-year estimated glomerular filtration rates were not different. Among the KT recipients followed up more than 3 years, new-onset cardiovascular disease occurred in nine patients, and coronary artery disease occurred more frequently in patients with stage IV periodontitis. However, diabetes was the independent predictor of new-onset coronary artery disease in multivariate logistic regression analysis.Conclusion: Our findings showed that periodontitis might be an important player in determining posttransplant outcomes in recipients. Further interventional trials to test whether treating periodontitis could modify transplant outcome are needed.

자기력을 이용한 충격형 액추에이터이 설계 및 성능 평가

민현진,임형준,김병규,김수현 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.7

자기력을 이용한 충격형 액추에이터의 설계 및 성능 평가

민현진,임형준,김병규,김수현,Min, Hyun-Jin,Lim, Hyung-Jun,Kim, Byung-Kyu,Kim, Soo-Hyun 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.7

For robotic endoscope, some researchers suggest pneumatic actuators based on inchworm motion. But, the existing endoscopes have not been replaced completely because human intestine is very sensitive and susceptible to damage. We design and test a new locomotion of robotic endoscope that allows safe maneuverability in the human intestine. The actuating mechanism is composed of two solenoids at each side and a single permanent magnet. When the current direction is reversed, repulsive force and attractive at the opposition side propels permanent magnet. Impact force against robotic endoscope transfers momentum from moving magnet to endoscope capsule. The direction and moving speed of the actuator can be controlled by adjustment of impact force. Modeling and simulation experiments are carried out to predict the performance of the actuator. Simulations show that force profile of permanent magnet is the dominant factor for the characteristic of the actuator. The results of simulations are verified by comparing with the experimental results.

Hypoxia Increases Epithelial Permeability in Human Nasal Epithelia

민현진,김창훈,김태훈,윤주헌 연세대학교의과대학 2015 Yonsei medical journal Vol.56 No.3

Purpose: The nasal mucosa is the first site to encounter pathogens, and it forms continuous barriers to various stimuli. This barrier function is very important in the innate defense mechanism. Additionally, inflammation of the nasal sinus is known to be a hypoxic condition. Here, we studied the effect of hypoxia on barrier functionin normal human nasal epithelial (NHNE) cells. Materials and Methods: The expression levels of various junction complex proteins were assessed in hypoxia-stimulated NHNE cells and human nasal mucosal tissues. We performed real-time polymerase chain reaction analysis, western blotting, and immunofluorescenceassays to examine differences in the mRNA and protein expression of ZO-1, a tight junction protein, and E-cadherin in NHNE cells. Moreover, we evaluated the trans-epithelial resistance (TER) of NHNE cells under hypoxic conditions to check for changes in permeability. The expression of ZO-1 and E-cadherin was measured in human nasal mucosa samples by western blotting. Results: Hypoxia time-dependently decreased the expression of ZO-1 and E-cadherin at the gene and protein levels. In addition, hypoxia decreased the TER of NHNE cells, which indicates increased permeability. Human nasal mucosa samples, which are supposedto be hypoxic, showed significantly decreased levels of ZO-1 and E-cadherinexpression compared with control. Conclusion: Our results demonstrate that hypoxia altered the expression of junction complex molecules and increased epithelialpermeability in human nasal epithelia. This suggests that hypoxia causes barrier dysfunction. Furthermore, it may be associated with innate immune dysfunctionafter encountering pathogens.

이차 발병한 비인강암 환자의 방사선 치료 후 발생한 다양한 합병증

민현진,김현수,정사명,이원상 대한이비인후과학회 2008 대한이비인후과학회지 두경부외과학 Vol.51 No.2

Due to anatomic restrictions and presentation with advanced local-regional diseases, radiotherapy has provided the standard of care for nasopharyngeal cancer. Although the local recurrence after curative radiation therapy has been often reported in the literature, reports of changes in the histopathologic findings of the tumor in the nasopharyngeal carcinoma are rare. Due to limitation in surgical treatment of nasopharyngeal carcoma, radiotherapy has been standard treatment for nasopharyngeal carcinoma. We present a case of multiple complications after radiotherapy in patients with the second primary nasopharyngeal cancer following a change in the histopathologic findings. (Korean J Otorhinolaryngol-Head Neck Surg 2008;51:198-201)

Clinical Features of Obstructive Sleep Apnea That Determine Its High Prevalence in Resistant Hypertension

민현진,박성하,조형주,조양제,김창훈,김다희,김하얀,최지인,이정권 연세대학교의과대학 2015 Yonsei medical journal Vol.56 No.5

Purpose: Resistant hypertension (HTN) occurs in 15–20% of treated hypertensive patients, and 70–80% of resistant hypertensive patients have obstructive sleep apnea (OSA). The characteristics of resistant HTN that predispose patients to OSA have not been reported. Therefore, we aimed to determine the clinical, laboratory, and polysomnographic features of resistant HTN that are significantlyassociated with OSA. Materials and Methods: Hypertensive patients (n=475) who underwent portable polysomnography were enrolled. The patients were categorized into controlled (n=410) and resistant HTN (n=65) groups. The risk factors for the occurrence of OSA in controlled and resistant hypertensive patients were compared, and independent risk factors that are associated with OSA were analyzed. Results: Out of 475 patients, 359 (75.6%) were diagnosed with OSA. The prevalence of OSA in resistant HTN was 87.7%, which was significantly higher than that in controlled HTN (73.7%). Age, body mass index, neck circumference, waist circumference, and hip circumference were significantly higher in OSA. However, stepwise multivariate analyses revealed that resistant HTN was not an independent risk factor of OSA. Conclusion: The higher prevalence and severity of OSA in resistant HTN may be due to the association of risk factors that are common to both conditions.

편심질량을 고려한 스크롤 압축기의 동특성 해석 ( Dynamic Analysis of Scroll Compressor Considered Eccentric Mass )

민현진,정우진,김성원 대한기계학회 1998 대한기계학회 춘추학술대회 Vol.- No.-

Nasal Obstruction due to Fibrous Dysplasia Invading Inferior and Middle Turbinates: A Case Report and Literature Review

민현진,박용균,민상기,김창훈 대한이비인후과학회 2016 대한이비인후과학회지 두경부외과학 Vol.59 No.6

Fibrous dysplasia (FD) is a rare type of fibro-osseous lesion characterized by progressive replacement of normal bone with immature tissue. The involvement of craniofacial bones is reported in 10% of FD cases, while the involvement of sinonasal cavity is extremely rare. We report a unique case of FD in which the primary complaint was nasal obstruction. As FD cases involving the turbinate bones are very rare, we also reviewed all reported cases of FD involving the inferior or middle turbinates. Based on our experience and a review of the relevant literature, we conclude that inferior and/or middle turbinectomy via endoscopic approach and septoplasty can improve nasal symptoms. Korean J Otorhinolaryngol-Head Neck Surg 2016;59(6):475-8

Neck Circumference and Lowest Oxygen Saturation Are Independently Associated with High Coexistence of Hypertension in Obstructive Sleep Apnea

민현진,박아영,김다희,이정권,박성하,조형주 연세대학교의과대학 2014 Yonsei medical journal Vol.55 No.5

Purpose: Obstructive sleep apnea (OSA) is considered an independent risk factor for hypertension. However, it is still not clear which clinical factors are related with the presence of hypertension in OSA patients. We aimed to find different physical features and compare the sleep study results which are associated with the occurrenceof hypertension in OSA patients. Materials and Methods: Medical records were retrospectively reviewed for patients diagnosed with OSA at Severance CardiovascularHospital between 2010 and 2013. Males with moderate to severe OSA patientswere enrolled in this study. Clinical and polysomnographic features were evaluatedto assess clinical variables that are significantly associated with hypertension by statistical analysis. Results: Among men with moderate to severe OSA, age was negatively correlated with hypertension (odds ratio=0.956), while neck circumferencewas positively correlated with the presence of hypertension (odds ratio=1.363). Among the polysomnographic results, the lowest O2 saturation during sleep was significantlyassociated with the presence of hypertension (odds ratio=0.900). Conclusion:Age and neck circumference should be considered as clinically significant features,and the lowest blood O2 saturation during sleep should be emphasized in predicting the coexistence or development of hypertension in OSA patients.

COVID-19 상기도 감염에 의한 후각장애의 약물치료

민현진 대한의사협회 2020 대한의사협회지 Vol.63 No.9

Postviral olfactory disorder refers to the sensorineural olfactory loss caused by upper respiratory tract infections. With the increasing awareness of olfactory or gustatory dysfunction as a potential early symptom of coronavirus disease 2019, postviral olfactory disorder has been attracting much attention. Postviral olfactory disorder is the most common type of olfactory disorder, especially among women aged over 50 years. Systemic or topical corticosteroids have commonly been used for treating this disorder, but the mechanism of corticosteroid action is unclear. Other medical treatment options such as alpha-lipoic acids and caroverine that stimulate nerve growth factor expression or prevent glutamatergic neurotoxicity have also been used. Although these drugs have been found to be useful in the treatment of postviral olfactory disorder in previous studies, the efficacy has not been statistically proven through a meta-analysis. Recently, olfactory training has been introduced in the treatment strategy for postviral olfactory disorder. It is a safe option without side effects that can be used for treating olfactory disorders caused by upper respiratory tract infections. Further rigorous studies are needed to determine the efficacy of the combination of drug treatment and olfactory training.