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Simultaneous Hard Tissue and Soft Tissue Graft with Dental Implant Placement and Provisionalization: A Case Report
No full textAchieving both esthetic and functional implant rehabilitation is crucial for the successful treatment of the anterior maxilla.
Adequate peri-implant alveolar bone and soft tissue are essential for optimal rehabilitation of the esthetic area, and there is a direct association between the implant position and prosthetic outcomes. Immediate provisionalization may also be advanta geous when combined with augmentation. This case report described the implant placement in a 25-year-old female patient who had lost her right maxillary lateral incisor (#12) due to trauma-induced avulsion. The treatment involved simultaneous grafting and collagenated, deproteinized bovine bone mineral, along with subepithelial connective tissue taken from the right maxillary tuberosity. A polyetheretherketone abutment and non-functional immediate provisionalization were performed by removing both the proximal and occlusal contacts on the composite resin crown. Clinical and radiographic evaluations revealed maintenance of stable ridge contour aspects for six months following surgical treatment. In summary, implant rehabilitation in the esthetic zone can be successful using simultaneous soft and hard tissue grafts. Moreover, soft tissue stabilization post-sub epithelial connective tissue grafting can be achieved through early or immediate visualization, along with immediate implant placement. [J Korean Dent Sci. 2024;17(2):84-91]N
Association between the Use of Proton Pump Inhibitors and Cardiovascular Diseases: A Nested Case-Control Study Using a National Health Screening Cohort
No full textWe investigated the association of proton pump inhibitor (PPI) use with the risk of stroke and ischemic heart disease (IHD). The Korean National Health Insurance Service-Health Screening cohort from 2002 to 2003, the participants of which were followed up until 2019, was used. In study I, 45,905 participants who were diagnosed with stroke were matched with 91,810 control I participants. The history of PPI medication was examined. In study II, 40,928 participants who were diagnosed with IHD were matched with 81,856 control II participants. In both study I and study II, the previous history of PPI medication was examined. A propensity score overlap-weighted multivariable logistic regression analysis was conducted to estimate the overlap-weighted odds ratios (ORs) of PPI use for stroke (study I) and IHD (study II). Current PPI use was linked with higher odds for stroke in study I. The odds for stroke were higher in groups with a longer duration of PPI use (OR = 0.96 [95% CI = 0.92-1.00] < 1.55 [1.50-1.61] < 1.62 [1.57-1.68] for < 30 days, 30 to 180 days, and >= 180 days of PPI use). Previous PPI use was linked with higher odds for IHD in study II. The odds for stroke were higher in groups with a longer duration of PPI use (OR = 1.13 [95% CI = 1.08-1.18] < 2.12 [2.04-2.21] < 2.60 [2.51-2.69] for <30 days, 30 to 180 days, and >= 180 days of PPI use). Current PPI medication is associated with a high risk of stroke and IHD. A longer duration of PPI medication was related to a higher risk of stroke and IHD. However, a prior history of PPI medication was not linked with a high risk of stroke or IHD.Y
Proposition of optimal self-curing method in horizontal-floating gate FET-type gas sensors for reliability improvement
No full textGas sensing technology has seen rapid advancements in recent years, finding applications in air quality monitoring, food freshness inspection, and medical diagnosis. However, to successfully integrate gas sensors into these applications, it is crucial to ensure their stability and long-term reliability. While previous studies have primarily focused on improving response, sensitivity, and selectivity, there has been limited research on enhancing their reliability. This study aims to address this gap by proposing a method to improve the reliability of horizontal floating-gate FET-type gas sensors using a self-curing approach. When the sensor is exposed to the repetitive program/erase operation, the FET transducer used as a sensor platform is damaged by the Fowler-Nordheim tunneling-induced stress. A significant increase in the trap density inside the gate oxide is observed after the P/E cycling. The parasitic bipolar junction (PBJT) inherent to the FET transducer flows a large current via the entire channel, generating a Joule heat. The trap is decreased by the annealing effects of the Joule heat, and the damaged gate oxide is fully recovered by the curing. The proposed PBJT curing can effectively improve the reliability of the sensor using the internal operation of the FET transducer without using bulky external equipment.N
Spatio-temporal heat risk analysis in construction: Digital twin-enabled monitoring
No full textTo effectively mitigate heat risks, it is crucial to pinpoint areas of high vulnerability and assess the severity of heat-related threats to construction workers. This paper advances the understanding of heat risks in construction by mapping the associated risks across time and space to support informed decision-making. This paper presents a framework for heat risk monitoring, enabled by a construction site digital twin. This framework leverages geometric modeling, incorporates real-time weather data from a weather station, and utilizes computational simulations for assessing spatio-temporal heat risks. Its effectiveness was validated through a case study in Stephenville, Texas, USA, where it demonstrated superior fidelity when compared to using the conventional black-globe thermometer. Moreover, the results substantiated that incorporating the spatio-temporal variability of heat risks enhances heat risk surveillance in construction workplaces. This approach offers practical insights into imminent heat-related threats, aiming to prevent potential heat-related accidents in construction.N
구리 촉매 아자이드-알카인 고리화 첨가 반응에 의한 금속 단백질의 화학적 확장
No full text학위논문(석사) -- 서울대학교 대학원 : 자연과학대학 화학부, 2024. 8. 송윤주.Relative to synthetic ligands, only a handful of canonical amino acids can constitute metal coordination sites, restraining the chemical space of metalloproteins. In this study, we genetically incorporated, multiplied, and modified a noncanonical amino acid, p-azidophenylalanine, by copper- assisted azide-alkyne cycloaddition (CuAAC). As a result, we seamlessly introduced finely tunable tris(triazole) ligands into a protein scaffold. The resulting artificial proteins endow unique spectroscopic properties of copper-binding sites distinct from natural ones composed of histidine residues. We also altered the denticity, steric hindrance, and electron density of the triazole depending on the applied alkynes for the ligand maturation, yielding either mononuclear or asymmetric dinuclear copper-binding sites. The structural fluxionality and tunability resemble the structural and functional diversity of synthetic multidentate triazole ligands used for CuAAC. Finally, the artificial copper-binding proteins facilitated the click reactions for exogenous substrates, representing the chemical potential of proteins as expandable and evolvable ligands for enzyme catalysis.합성을 통해 얻은 리간드에 비해 표준 아미노산은 금속 단백질에 금속 배위 자리를 형성하는 경우가 적은 것으로 알려졌다. 본 연구에서는 비표준 아미노산인 파라-아자이도 페닐알라닌을 단백질에 도입하고, 구리에 의해 촉매되는 아자이드-알카인 고리화첨가반응을 통해 변형시켰다. 그리고나서 새로 만들어진 트리스-트라이아졸 구조 단백질이 구리가 결합할 수 있는 특이적인 공간 및 스펙트럼 특성을 가지고 있음을 표준 아미노산인 히스티딘과의 비교를 통해 확인하였다. 그리고 새로운 단백질은 함께 반응하는 알카인의 종류에 따라 단일 또는 이중의 결합 부위가 형성됨을 반응성을 통해 확인하였다. 따라서 본 연구를 통해 확인된 사실들은 단순한 금속 단백질의 설계에 그치지 않고 더 나아가 금속 효소 촉매의 확장을 가능하게 하고 진화를 할 수 있는 리간드로써의 잠재력을 나타낸다.Abstract 1
Contents 3
Lists of Figures 5
Lists of Tables 6
Lists of schemes 7
CHAPTER 1. Introduction . 8
Background 9
Purpose of Research . 19
CHAPTER 2. Design of Tris(triazole) incorporated metalloprotein 22
2.1 Introduction 23
2.2 De novo design of tris(triazole) metal-binding site . 24
2.3 Characterization of the designed metalloproteins . 39
2.3.1 HR-MS analysis . 39
2.3.2 ICP-MS 43
2.3.3 UV-VIS spectra of the oxidized states . 46
2.3.4 Cyclic voltammetry of de novo metalloproteins 50
2.3.5 FT-IR spectra 55
2.4 Conclusion 57
2.5 Materials and methods . 58
Chapter 3. Expansion of metalloprotein into metalloenzyme :
４
Clickzyme 64
3.1 Introduction 65
3.2 In vitro activity assays . 66
3.2.1 Click reaction activity . 66
3.2.2 Ascorbate consumption assay 71
3.2.3 HRP assay . 73
3.3 Conclusion 75
3.4 Materials and Methods . 76
References . 78
Abstract in Korean 83
５
Figure Contents
Figure 1. A brief overview of σ-bond and π bond in metal-coordination 9
Figure 2. Classification for metal-coordinating ligands 10
Figure 3. Examples of metal coordinating ligands. . 10
Figure 4. (a) The reaction scheme for making novel metal-binding sites.
(b) The structures of alkynes applied for this work 26
Figure 5. Structural analysis for designing novel metal-binding sites 27
Figure 6. 12 % SDS-PAGE gel for protein expression test 31
Figure 7. Protein purification 33
Figure 8. S24Z modification . 35
Figure 9. 1H NMR of pAzF 37
Figure 10. 13C NMR of pAzF 37
Figure 11. High resolution mass spectrometry 39
Figure 12. ICP-MS 43
Figure 13. Metalation 46
Figure 14. Cyclic voltammeogram 50
Figure 15. FT-IR spectrum 55
Figure 16. Clickzyme activity 66
Figure 17. HPLC traces of the reaction mixture . 67
Figure 18 Fluorescence yield of the reaction mixture 68
Figure 19. Time-dependent ascorbate consumption 71
Figure 20. Time dependent H2O2 formation 73
６
Table Contents
Table 1. Structural analysis for metalloprotein design . 28
Table 2. Difference between calculated and detected mass 41
Table 3. Redox potential of the designed mutants 52
Table 4. Conversion of HPLC area into yield 68
Table 5. Conversion of fluorescence into yield 69
７
Scheme Contents
Scheme 1. The reaction scheme of (a) Huisgen 1,3-dipolar cycloaddition
and (b) CuAAC . 13
Scheme 2 . Proposed mechanism of CuAAC 16
Scheme 3. Synthesis of p-azido-L-phenylalanine . 62
Scheme 4. Fluorogenic reaction scheme for click activity 66
Scheme 5. Reaction scheme of ascorbate consumption and HRP assay 71석
비판막성 심방세동에 의한 뇌경색의 이차 예방을 위한 와파린과 비 비타민 K 경구용 항응고제의 비교
No full text학위논문(박사) -- 서울대학교 대학원 : 의과대학 의학과, 2024. 8. 권형민.심방 세동은 뇌졸중의 주요 위험 인자로, 심방 세동에 의한 뇌졸중은 다른 기전으로 인해 발생한 뇌경색에 비해 더 심각하고 그 예후가 좋지 않다. 따라서, 심방 세동을 가진 환자들에게 있어서 뇌졸중의 발생 (일차 예방) 과 재발을 예방 (이차 예방)하는 것은 중요한 문제이다. 오랜 세월동안 이 환자들의 일차 및 이차 예방을 위해 와파린이 표준 치료제로 사용되어 왔지만, 와파린은 장기간 사용에 있어 여러 문제점이 있었다. 최근 들어 비 비타민 K 경구용 항응고제 (NOAC)들이 개발되었고, 다양한 임상 시험 (randomized controlled study)들과 대규모 관찰 연구들을 통해 와파린보다 심방 세동 환자의 뇌졸중 일차
예방에 있어서 더 안전하고 열등하지 않은 효과를 보이는 것을 입증하였다. 하지만, 이미 심방 세동으로 인한 뇌졸중이 발생한 환자들에게 있어서 재발을 방지하는 이차 예방과 관련되어서는 많은 연구가 이루어지지 못했다. 이 연구에서는 국내 국민건강보험 공단 빅데이터 자료를 이용하여, 심방 세동으로 인한 뇌졸중 환자의 이차 예방에 있어서 와파린과 NOAC 의 효과 및 안전성에 대해 비교하고자 한다. 아울러, 각 NOAC 들 간의 비교를 통해서 현재 국내에 NOAC 처방 현황 및 한국인에게 더 안전하고 효과적인 NOAC 은 어떤 것인지에 대해서도 알아보고자 한다. 2015 년에서 2019 년 사이 국민건강보험 공단의 레지스트리에 등록되어 있는 환자들 중 뇌경색 및 비판막성 심방 세동의 ICD-10-CM code 를 모두 가진 환자들을 분석 대상으로 삼았다. 뇌경색 진단의 실효성을 얻기 위해 뇌 자기공명영상을 입원 직전 혹은 직후 수행한 환자만을 대상으로 하였으며 처음으로 와파린 혹은 NOAC 을 사용한 환자를 대상으로 했다. 주요 효과 변수는 뇌경색 + 전신 색전증으로 정의하였으며, 주요 안전 변수는 뇌출혈 + 위장관 출혈으로 정의했다. 그 외에 각각의 뇌경색, 전신 색전증, 주요 출혈, 사망을 이차 결과 변수로 분석했다. 관찰 기간은 2019 년 12 월까지로 정의하였으며, cox regression analysis model 을 기반으로 와파린 사용자와 NOAC 사용자 간의 주요 결과 변수들의 차이를 분석하였다. 총 21,064 명의 경구 항응고제 사용자가 분석 대상이 되었으며, 그 중 와파린 사용자가 2,925 (13.9%) 명, NOAC 사용자가 18,139 (86.1%) 명이었다. 양 군 간의 유의미한 표본 크기 차이로 인한 교란 변수들의 차이를 줄이기 위해 1:4 propensity score matching 을 수행하였다. 관찰 기간의 중간 값은 15.5 달이었다. 시간 및 교란 변수들을 보정한 다변량 분석에서 NOAC 사용자는 와파린 사용자에 비해 유의미하게 적은 뇌경색 + 전신 색전증 위험도를 보였다 [adjusted hazard ratio (aHR), 0.86; 95% confidence interval (CI), 0.78-0.95]. NOAC 은 출혈 부작용에 있어서도 와파린보다 안전한 결과를 보였다 (aHR, 0.78; 95% CI, 0.68-0.89). NOAC 용량에 따른 와파린과의 비교 분석에서, 표준 용량의 NOAC 은 와파린보다 더 효과적이고 안전한 결과를 보였다. 하지만, 저용량 NOAC 의 경우 뇌경색 + 전신 색전증의 예방 효과에 있어서도, 출혈성 부작용에 있어서도 와파린과 통계적으로 유의미한 차이를 보이지 못했다. 종류에 따른 분석에서는 dabigatran, rivaroxaban, apixaban, edoxaban 의 네 종류 NOAC 모두 와파린보다 더 뛰어난 이차 예방 효과를 보였다. 출혈 부작용에 있어서는 rivaroxaban 을 제외한 세 종류의 NOAC 은 모두 와파린보다 안전한 결과를 보여주었으며, rivaroxaban 은 와파린과 비슷한 정도의 출
부작용 위험도를 보였다. 한국 건강보험공단 빅데이터를 이용한 전국 리얼 월드 데이터 분석에서, NOAC 은 비판막성 심방 세동으로 인한 뇌졸중 환자의 이차 예방 효과 및 안전성에 있어서 모두 와파린보다 우수한 모습을 보였다. 모든 종류의 NOAC 은 와파린보다 이차 예방 효과가 우수하였으며, rivaroxaban 을 제외한 모든 NOAC 들은 와파린보다 더 안전하였 .
한국에서 NOAC 의 처방이 급증하고 있는 만큼, 환자의 특성에 맞는 적절한 NOAC 을 가이드라인에 맞는 용량으로 사용하는 것이 중요해 보인다.Atrial fibrillation (AF) is a major risk factor for stroke, and stroke caused by AF is more serious and has a poorer prognosis than cerebral infarction caused by other mechanisms. Therefore, preventing stroke occurrence (primary prevention) and recurrence (secondary prevention) is an important issue in patients with AF. Warfarin has been used as a standard treatment for primary and secondary prevention of these patients for a long time, but warfarin has several problems with long-term use. Recently, non-vitamin oral anticoagulants (NOACs) have been suggested, and through various clinical trials and large-scale observational studies, they have been proven to be safer and non-inferior to warfarin in the primary prevention of stroke in patients with AF. However, not much research has been done on preventing recurrence in patients who have already had a stroke due to AF. In this study, we aim to compare the effectiveness and safety of warfarin and NOAC in secondary prevention of stroke patients due to AF using big data from the National Health Insurance Service (NIHS) in Korea. In addition, through comparison between each NOAC, we would like to find out the current status of NOAC prescriptions in Korea and which NOAC is safer and more effective for Koreans. Among patients registered in the NHIS registry between 2015 and 2019, patients with both ICD-10-CM codes for ischemic stroke and non-valvular atrial fibrillation were analyzed. To ensure reliability of cerebral infarction diagnosis, only patients who had brain magnetic resonance imaging performed immediately or immediately after hospitalization were included, and patients who used warfarin or NOAC for the first time were included. The primary effectiveness outcome was defined as ischemic stroke + systemic embolism, and the primary safety outcome was defined as intracranial hemorrhage + gastrointestinal hemorrhage. Furthermore, ischemic stroke, systemic embolism, major bleeding, and all-cause of death were analyzed as secondary outcome variables. The observation period was defined as until December 2019, and the differences in outcome variables between warfarin users and NOAC users were analyzed based on the cox regression analysis model. A total of 21,064 oral anticoagulant users were analyzed, of which 2,925 (13.9%) were warfarin users and 18,139 (86.1%) were NOAC users. To reduce the difference in variables due to the significant difference in sample size between the two groups, 1:4 propensity score matching was performed. The median observation period was 15.5 months. In multivariate analysis adjusting for time and confounding variables, NOAC users showed a significantly lower risk of ischemic stroke + systemic embolism than warfarin users [adjusted hazard ratio (aHR), 0.86; 95% confidence interval (CI), 0.78-0.95]. NOACs showed safer results than warfarin also in bleeding complications (aHR, 0.78; 95% CI, 0.68-0.89). In a comparative analysis with warfarin according to NOAC dose, standard-dose NOAC showed more effective and safer results than warfarin. However, in the case of low-dose NOAC, there was no statistically significant difference from warfarin in the preventive effectiveness of "ischemic stroke + systemic embolism" or in hemorrhagic complications. In an analysis by type, all four types of NOACs - dabigatran, rivaroxaban, apixaban, and edoxaban - showed better secondary prevention effectiveness than warfarin. In terms of bleeding complications, dabigatran, apixaban, and edoxaban showed safer results than warfarin, and rivaroxaban showed a risk of bleeding complications similar to warfarin. In this nationwide real-world data analysis using the Korean NHIS big data, NOAC was shown to be superior to warfarin in both secondary prevention effectiveness and safety in stroke patients due to nonvalvular AF. All types of NOACs had better secondary prevention effectiveness than warfarin, and dabigatran, apixaban, and edoxaban were safer than warfarin. As the prescription of NOACs is rapidly increasing in Korea, it seems important to use appropriate NOACs suited to the patient's characteristics at a dose that meets the guidelines.Abstract 1
Contents 4
List of tables 5
List of figures 6
Introduction 7
Methods 9
Results 14
Discussion 17
Reference 23
Abstract in Korean 48박
셀룰로오스 나노섬유 골조가 포함된 폴리에틸렌 글라이콜 하이드로젤의 물리적 특성 조절
No full text학위논문(석사) -- 서울대학교 대학원 : 농업생명과학대학 농림생물자원학부, 2024. 8. Ki ChangSeok.Hydrogels are composed of polymer networks that retain large amounts of water. Due to their versatility, they are used widely in industry and scientific research. Nevertheless, the trade-off in hydrogel formation between stiffness and mesh size remains a crucial consideration for practical applications. This study describes a novel approach to controlling hydrogel stiffness and mesh size, using hydrogels created by hybridizing poly(ethylene glycol) diacrylate (PEGDA) and methacrylated TEMPO-oxidized cellulose nanofibers (T-CNFMA). T-CNF was sonicated until reaching desired width and shear moduli. Following optimization of the feed ratio, T-CNFMA with a degree of substitution of ~2.04 mmol/g was obtained. Incorporation of T-CNFMA in PEGDA network allowed the independent control of hydrogel stiffness and mesh size, as the CNFs provided the framework of hydrogel. Adjustment of the PEGDA/T-CNFMA ratio enabled the independent manipulation of swelling ratio and shear modulus of the hydrogel. Structural analyses revealed that an increase in the T-CNFMA content in the presence of a low amount of PEGDA resulted in a large mesh size but a constant stiffness. The diffusivity test was consistent with the properties of the hydrogels. The hybrid hydrogel was then seeded with A549 cells to investigate its potential as a cell culture matrix, by assessing cell adhesion. It indicates that the hybrid hydrogel can be used to systemically analyze cell responses to stiffness and mesh size factors.
Keyword: Cell culture substrate, hydrogel, methacrylation, independent control, PEGDA, T-CNFMA, stiffness, swelling ratio
Student Number: 2022-28463초 록
내부에 다량의 물을 함유한 고분자 기반 3차원 물질인 하이드로젤은 산업 및 과학 분야에서 널리 사용된다. 그러한 범용성에도 불구하고, 하이드로젤의 강성과 메쉬 크기 사이에 존재하는 종속적인 반비례 관계는 그것의 특성 제어에 있어 주 장애 요소로 손꼽힌다. 본 연구에서는 폴리에틸렌글리콜 디아크릴레이트 (PEGDA)와 메타크릴기로 개질된 TEMPO 산화 셀룰로오스 나노 섬유(T-CNFMA)의 복합화를 통해 하이드로젤의 강성과 메쉬 크기를 제어하는 새로운 접근법을 제시하였다. 초음파 처리를 통해, TEMPO 산화 셀룰로오스 나노 섬유가 적절한 폭과 전단 계수를 갖도록 조절하였고, 개질에 투입되는 메타크릴 언하이드라이드의 비율을 최적화해, 약 2.04 mmol/g의 치환도를 갖는 T-CNFMA를 합성했다. 상기된 두 고분자 성분 중 T-CNFMA는 하이드로젤의 골격 구조로 사용되어 강성과 메쉬 크기의 독립적인 조절을 가능하게 했다. 또한, PEGDA와 T-CNFMA의 혼합 비율은 복합 하이드로젤의 팽윤도와 전단 탄성률을 독립적으로 조절하는 데 핵심적인 역할을 했다. PEGDA의 비율을 감소시키며 T-CNFMA의 비율을 증가시킬수록 일정한 강성하에서 큰 메쉬 크기와 증가된 팽윤도를 나타냈다. 복합 하이드로젤의 확산도 역시, 앞선 특성과 동일한 경향성을 보였다. 복합 하이드로젤의 세포 배양 매트릭스로써의 잠재적인 사용을 평가하기 위하여, A549 세포를 복합 하이드로젤 위에 분주하고 세포 접착 특성을 평가하였다. 위 결과는, 복합 하이드로젤이 강성 및 메쉬 크기 인자에 대한 독립적인 조절을 수행하고, 세포 특성을 체계적으로 분석하는 역할을 수행함을 보인다.
주요어: 세포배양기질, 하이드로젤, 메타크릴화, 독립적 조절, PEGDA, T-CNFMA, 강성, 팽윤도
학번: 2022-28463Abstract ⅰ
Contents ⅱ
List of Tables ⅴ
List of Figures ⅵ
Ⅰ. INTRODUCTION 1
Ⅱ. LITERATURE SURVEY 6
2.1. Theory of hydrogel 6
2.2. Independent control of stiffness and mesh size in hydrogel 9
2.3. Cellulose nanofiber 10
2.4. Cellulose nanofiber hydrogel 11
2.5. Poly(ethylene glycol) (PEG) 13
2.6. PEG hydrogel for biomedical field 13
Ⅲ. MATERIALS AND METHODS 15
3.1. Materials 15
3.2. Methacrylation of T-CNF 15
3.3. Hydrogel fabrication 16
3.4. Rheometry 17
3.5. Electron microscopy 17
3.6. Diffusivity measurement 18
3.7. Cell culture 19
3.8. Fluorescence microscopy 20
3.9. Statistical analysis 21
Ⅳ. RESULTS AND DISCUSSION 24
4.1. Methacrylation of T-CNF 24
4.2. Fabrication of PEGDA/T-CNFMA hybrid hydrogels 32
4.3. Controlled diffusivity according to the T-CNFMA content 37
4.4. Cell adhesion of PEGDA/T-CNFMA hybrid hydrogels 46
Ⅴ. CONCLUSION 54
Ⅵ. REFERENCES 55
초 록 66석
엽록소 형광을 통한 벼 도열병의 조기탐지
No full text학위논문(석사) -- 서울대학교 대학원 : 농업생명과학대학 농림생물자원학부, 2024. 8. HYUNGSUK KIM.Rice blast, one of the major diseases causing significant rice yield loss, downregulates the photosynthetic activity and induces aggressive spread of cell death near the infection site. Sun-induced chlorophyll fluorescence (SIF), which is mechanistically linked with photosynthesis, can quantify the impact of plant physiological stress by environmental changes, but remains yet to be tested for quantifying biological stress impacts. Here, we assessed the potential of using SIF for quantifying biological stress impact on plant physiology by using chlorophyll fluorescence (CF) induced by an artificial light source for rice blast-inoculated rice plants. To fully understand the role of CF in rice blast detection, we obtained the full spectrum of chlorophyll fluorescence at small leaf areas (Ø 4 mm) from two rice cultivars inoculated for rice blast. CF yield (ΦF), which is normalized by incident radiation, sensitively responded to rice blast within 24 and 96 hour post inoculation for susceptible and resistant cultivars, respectively. We confirmed that the ΦF showed strong sensitivity in response to different doses of inoculation and to cultivar difference. In addition to ΦF results, we further investigated the role of red to far-red CF ratio (CFR:FR) in rice blast detection. CFR:FR, which was previously reported to be tightly coupled with chlorophyll contents, captured the impact of rice blast inoculation to some extent while green chlorophyll vegetation index did not show any difference across all inoculated groups. CFR:FR results may imply that it contains unique physiological information apart from structural information. Overall, our study highlights the unique role of CF in the detection of rice blast and will further expand our understanding of plant pathology. Keyword : Chlorophyll fluorescence; Rice blast; Red to far-red chlorophyll fluorescence ratio; Crop disease; Asymptomatic detection; Student Number : 2022-21429벼 도열병은 광합성을 저해하고 감염 부위 근처의 세포사를 유도하여 벼 수확량에 심각한 손실을 초래하는 식물병이다. 광합성과 높은 상관관계를 보이는 태양광유도 엽록소형광은 환경적 스트레스로 인한 작물의 스트레스를 정량화할 수 있는 잠재력이 있지만, 생물학적인 스트레스의 정량화에 대해서는 추가적 연구가 필요한 상황이다. 본 연구에서는 벼 도열병에 접종된 벼와 인공광원유도 엽록소형광을 통해 태양광유도 엽록소형광이 지니는 생물학적인 스트레스가 작물생리에 미치는 영향에 대한 정량화 능력을 평가하였다. 벼 도열병의 조기탐지에서 엽록소형광이 지니는 잠재력을 완전히 이해하기 위해, 우리는 서로 다른 두 품종의 도열병 접종 벼에서, 잎 수준 풀스펙트럼의 엽록소형광을 4mm 지름의 영역에서 수집하였다. 엽록소형광을 입사광으로 정규화함으로서 계산되는 엽록소형광의 수율 (ΦF)은 이병성 품종과 저항성 품종에 대하여 각각, 도열병 접종 후 24시간과 96시간 뒤에 도열병에 대한 영향을 탐지하였다. 우리는 ΦF이 접종 농도의 차이 및 품종의 저항성의 차이에 민감하게 반응함을 확인했다. ΦF에 더해서, 우리는 적색광 영역의 엽록소형광과 원적색광 영역의 엽록소형광의 비율(CFR:FR)이 벼 도열병 탐지에서 지니는 잠재력도 연구하였다. 기존 연구를 통해 엽록소 함량과 높은 상관관계를 보인다고 보고된 CFR:FR은 엽록소 함량과 높은 상관을 보이는 식생지수가 유의한 차이를 보이지 않은 모든 처리구에서 제한적으로 벼 도열병 접종 영향을 탐지하였다. 본 연구의 결과는 CFR:FR이 작물의 구조적 정보와는 별개인 고유의 생리학적 정보를 포함하고 있음을 시사한다. 본 연구는 벼 도열병
탐지에서 엽록소형광이 지니는 고유한 잠재력을 강조하며, 식물 병리학에 대한 이해를 확장할 것으로 기대된다.Introduction 1
Materials and Methods 4
Results 9
Discussion . 16
Conclusion 20
Supplementary materials 21
References . 22
Abstract in Korean . 32석
Costs Associated with Transcatheter Aortic Valve Implantation and Surgical Aortic Valve Replacement in Korea
No full textBackground: This study compared the costs associated with transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) in Korea by utilizing the National Health Insurance Service database. Methods: Between June 2015 and May 2019, 1,468 patients underwent primary isolated transfemoral TAVI, while 2,835 patients received primary isolated SAVR with a bioprosthesis. We assessed the costs of index hospitalization and subsequent healthcare utilization, categorizing the cohort into 6 age subgroups: <70, 70–74, 75–79, 80–84, 85–89, and ≥90 years. The median follow-up periods were 2.5 and 3.0 years in the TAVI and SAVR groups, respectively. Results: The index hospitalization costs were 41.0 million Korean won (KRW) (interquartile range [IQR], 39.1–44.7) for the TAVI group and 24.6 million KRW (IQR, 21.3–30.2) for the SAVR group (p<0.001). The TAVI group exhibited relatively constant index hospitalization costs across different age subgroups. In contrast, the SAVR group showed increasing index hospitalization costs with advancing age. The healthcare utilization costs were 5.7 million KRW per year (IQR, 3.3–14.2) for the TAVI group and 4.0 million KRW per year (IQR, 2.2–9.0) for the SAVR group (p<0.001). Healthcare utilization costs were higher in the TAVI group than in the SAVR group for the age subgroups of <70, 70–74, and 75–79 years, and were comparable in the age subgroups of 80–84, 85–89, and ≥90 years. Conclusion: TAVI had much higher index hospitalization costs than SAVR. Additionally, the overall healthcare utilization costs post-discharge for TAVI were also marginally higher than those for SAVR in younger age subgroups.Y
Immunomodulators for immunocompromised patients hospitalized for COVID-19: a meta-analysis of randomized controlled trials
No full textBackground Although immunomodulators have established benefit against the new coronavirus disease (COVID-19) in general, it is uncertain whether such agents improve outcomes without increasing the risk of secondary infections in the specific subgroup of previously immunocompromised patients. We assessed the effect of immunomodulators on outcomes of immunocompromised patients hospitalized for COVID-19. Methods The protocol was prospectively registered with PROSPERO (CRD42022335397). MEDLINE, Cochrane Central Register of Controlled Trials and references of relevant articles were searched up to 01-06-2022. Authors of potentially eligible randomized controlled trials were contacted to provide data on immunocompromised patients randomized to immunomodulators vs control (i.e., placebo or standard-of-care). Findings Eleven randomized controlled trials involving 397 immunocompromised patients hospitalized for COVID19 were included. Ten trials had low risk of bias. There was no difference between immunocompromised patients randomized to immunomodulators vs control regarding mortality [30/182 (16.5%) vs 41/215 (19.1%); RR 0.93, 95% CI 0.61-1.41; p = 0.74], secondary infections (RR 1.00, 95% CI 0.64-1.58; p = 0.99) and change in World Health Organization ordinal scale from baseline to day 15 (weighed mean difference 0.27, 95% CI -0.09-0.63; p = 0.15). In subgroup analyses including only patients with hematologic malignancy, only trials with low risk of bias, only trials administering IL -6 inhibitors, or only trials administering immunosuppressants, there was no difference between comparators regarding mortality. Interpretation Immunomodulators, compared to control, were not associated with harmful or beneficial outcomes, including mortality, secondary infections, and change in ordinal scale, when administered to immunocompromised patients hospitalized for COVID-19.Y