• Korean Journal of Radiology
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• 제24권4호
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• pp.294-304
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• 2023

Objective: We aimed to investigate whether image standardization using deep learning-based computed tomography (CT) image conversion would improve the performance of deep learning-based automated hepatic segmentation across various reconstruction methods. Materials and Methods: We collected contrast-enhanced dual-energy CT of the abdomen that was obtained using various reconstruction methods, including filtered back projection, iterative reconstruction, optimum contrast, and monoenergetic images with 40, 60, and 80 keV. A deep learning based image conversion algorithm was developed to standardize the CT images using 142 CT examinations (128 for training and 14 for tuning). A separate set of 43 CT examinations from 42 patients (mean age, 10.1 years) was used as the test data. A commercial software program (MEDIP PRO v2.0.0.0, MEDICALIP Co. Ltd.) based on 2D U-NET was used to create liver segmentation masks with liver volume. The original 80 keV images were used as the ground truth. We used the paired t-test to compare the segmentation performance in the Dice similarity coefficient (DSC) and difference ratio of the liver volume relative to the ground truth volume before and after image standardization. The concordance correlation coefficient (CCC) was used to assess the agreement between the segmented liver volume and ground-truth volume. Results: The original CT images showed variable and poor segmentation performances. The standardized images achieved significantly higher DSCs for liver segmentation than the original images (DSC [original, 5.40%-91.27%] vs. [standardized, 93.16%-96.74%], all P < 0.001). The difference ratio of liver volume also decreased significantly after image conversion (original, 9.84%-91.37% vs. standardized, 1.99%-4.41%). In all protocols, CCCs improved after image conversion (original, -0.006-0.964 vs. standardized, 0.990-0.998). Conclusion: Deep learning-based CT image standardization can improve the performance of automated hepatic segmentation using CT images reconstructed using various methods. Deep learning-based CT image conversion may have the potential to improve the generalizability of the segmentation network.

• 생명과학회지
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• 제34권3호
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• pp.170-178
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• 2024

지방줄기세포는 다양한 세포로 분화할 수 있어서 세포치료제로 주목받고 있으나 세포 증식 속도가 느리고 세포의 수명이 짧아 임상 적용에 어려움이 있다. 본 연구팀은 선행연구에서 지방줄기세포의 증식속도를 향상시키고 세포 수명을 연장시키기 위해 SV40의 T항원 유전자를 사람의 ADSC에 도입하여 불사화시킨 ADSC 세포주를 제작하였으며 ADSC-T라고 명명하였다. 본 연구에서는 ADSC-T 세포의 분화능력을 검증하고, ADSC-T 세포를 배양하여 획득한 무혈청 배양액의 항염증 효능을 평가하였다. 그 결과, ADSC-T 세포주는 지방세포와 골세포로 분화할 수 있는 능력을 보유하고 있어 줄기세포의 가장 중요한 특징인 분화능력을 유지하고 있음을 알 수 있었다. 또한 ADSC-T의 배양액은 염증을 유발하는 NF-κB의 활성을 억제하였고, NF-κB의 표적 유전자인 COX-2와 iNOS의 발현도 억제하였다. 또한 ADSC-T 배양액은 ERK, JNK, p38의 인산화를 저해하여 세포 내 염증 유발 신호 전달 회로인 MAPKs 회로를 억제하는 것으로 나타났으며, 염증을 유발하는 cytokine인 TGF-β, TNF-α, IL-6, IL-13의 발현도 억제하는 효과를 보여 강한 항염증 효능이 있을 것으로 추정되었다. 실제로, 아토피 모델 쥐인 Nc/Nga 마우스를 DNCB로 처리하여 아토피 피부염을 유발한 뒤 ADSC-T 배양액을 도포한 결과 강한 치료 효과를 나타내었다. 이상의 결과로부터, 불사화된 ADSC-T 세포주는 지방줄기세포의 장점과 효능을 유지하고 있으며 향후 지방줄기세포의 세포 수급 문제를 해결할 수 있을 뿐 아니라 임상 적용이 가능한 배양액의 생산에도 널리 이용될 수 있을 것으로 사료된다.

• 대한간호
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• 제29권4호
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• pp.51-72
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• 1990

The purpose of this study was to determine whether Severance Hospice Home Care Pro gram was able to meet its objectives. This was done in order to show in detail the effects of hospice home care on the quality of life of terminally ill patients and to provide rationale for setting up more hospice home care programs in korea. The results of the study were as follows: The subjects of the study were 100 terminally ill patients who hnd died 'while in the hospice program and 64 family members who were registered with Severance Hospice Home Care Program between march 1988 and Feb. 1990. The nursing needs of these terminally ill patients were assessed by the nursing records of these patients. The need for pain control(82%) was the highest nursing need so far as the physical aspects were concerned. This was followed by poor appetite(37%), 8 dyspnea(34%), nausea and vomiting(30%) in that order of frequency. In reqard to spiritual needs, the need for religious' support was also high at 72%. Their main psychological symptoms were anxiety and fear(34% ). Burn-out was a major problem for 44% of the family members. The psychological process experiencel by the terminal ill patients was compared to the dying process, described by Kiibler Ross. In comparison of the five stages outlined by kubler Ross with the dying process of the subjects it was found that the subjects not only experienced the five stages but also experienced denial and doubt-fulness or denial with acceptance or acceptance with the expectation of a miracle. But rather than acceptance of the dying process, giving up was a frequent end point of the psychological process, of the subjects. However, when the combination of states was observed, most of the patients reached the state of acceptance in the dying process. It was difficult to identify a definite pattern of change in the psychological process of the subjects. Also it was difficult to identify the factors that influenced the psychological process. The symptoms of the terminally j]] subjects just before dying, that is, 3-4 days before dying included apparent signs of dying. These were a reduction of intake(77%), reduction of the amount of urination(63%), increase in sleeping time (64%) and acceptance of dying by patients and their families who had been unaccepting be before that time(66%). The primary care givers(family member's) degree of satisfaction with the care given to the patient by the hospice was 88.7%. The results of this study show that Severance Hospice Home Care Program had a positie effeet on the quality of life of the terminally ill patients and their family members as they faced the death of the patient. It can be seen from this study that there is an urgent need to extend hospice programs - in order to provide quality of care for terminally ill patient and their families. Based upon the reesults of this study several suggestions are presente as follows: 1) A follow up study should be carried out to identify the dying process as it is unique to Korea. 2) A comparison should be made of other hospice care programs. 3) A comparison study should- be made with subjects who do not receive any hospice care as compared to those who do by use of an experimental and control group methodology. 4) There is a need to determine a scientific method to adequeto measure the interventions carried out to meet the hospice patients nursing care needs. 5) A study should be made using quality research methodology to evaluate effects of hospiec care from the patients, their family members and the nurrse's perspective.