FLASH radiotherapy (FLASH RT) is a technique to deliver ultra-high dose rate in a fraction of a second. Evidence from experimental animal models suggest that FLASH RT spares various normal tissues including the lung, gastrointestinal track, and brain from radiation-induced toxicity (a phenomenon known as FLASH effect), which is otherwise commonly observed with conventional dose rate RT. However, it is not simply the ultra-high dose rate alone that brings the FLASH effect. Multiple parameters such as instantaneous dose rate, pulse size, pulse repetition frequency, and the total duration of exposure all need to be carefully optimized simultaneously. Furthermore it is critical to validate FLASH effects in an in vivo experimental model system. The exact molecular mechanism responsible for this FLASH effect is not yet understood although a number of hypotheses have been proposed including oxygen depletion and less reactive oxygen species (ROS) production by FLASH RT, and enhanced ability of normal tissues to handle ROS and labile iron pool compared to tumors. In this review, we briefly overview the process of ionization event and history of radiotherapy and fractionation of ionizing radiation. We also highlight some of the latest FLASH RT reviews and results with a special interest to neurocognitive protection in rodent model with whole brain irradiation. Lastly we discuss some of the issues remain to be answered with FLASH RT including undefined molecular mechanism, lack of standardized parameters, low penetration depth for electron beam, and tumor hypoxia still being a major hurdle for local control. Nevertheless, researchers are close to having all answers to the issues that we have raised, hence we believe that advancement of FLASH RT will be made more quickly than one can anticipate.

Cervical cancer and its precursors are caused principally, if not exclusively, by HPV infection and HPV DNA is found in more than 90% of cervical cancers. Cervical cytology is limited by its false negativity and this may be supplimented by other adjunctive test such as HPV test. It is therefore important to explore the use of HPV DNA detection as a primary or supplementary screening method and to determine whether HPV typing can be used as a predictor of a lesion's clinical behavior. Cervical cytology and Hybrid Capture test for HPV detection were performed in 450 asymtomatic wornen visited Health Care Center in Kangnam St. Mary's Hospital,and none of whom was believed to have current cervical disease. The Papanicolaou cytology results were classified by The Bethesda System : 333(74.%) women were classified to within normal limit, 19(4.2%) benign reactive change, 38(8.4%) ASCUS, 59(13%) low grade SIL, and only one woman high grade SIL. Twenty five of 450(5.6%) women showed HPV infection by Hybid Capture test. Among 98 wornen with abnormal Papanicolaou cytology, 16(16.3%) women showed HPV DNA positivity. (continue)
Delivery of Health Care ; DNA* ; Female ; Humans* ; Mass Screening* ; Papilloma* ; Uterine Cervical Neoplasms

No abstract available.

OBJECTIVE: To Compare the conventional Pap smear with the Liquid Pap smear in screening of cervical cancer and to evaluate the correspondence of their biopsy results. METHODS: From August 1, 2003 to July 31, 2005, the conventional Pap smears and the Liquid Pap smears were performed in 12,757 and 6,870 women, respectively. The results of 252 conventional Pap smear and 227 Liquid Pap smear were confirmed by colposcopic biopsy and evaluated for sensitivity, specificity, positive predictability, negative predictability and false negativity. RESULTS: In Liquid Pap smear, there were higher proportions of ASCUS, LSIL, HSIL and CIS. And the ratio of ASCUS/LSIL were 3.32 and 3.04 in conventional Pap smear and Liquid Pap smear respectively. The conventional Pap smear showed sensitivity 71.8%, specificity 93.9%, positive predictability 82.3%, negative predictability 89.4%, and false negativity 28.2%, while the Liquid Pap smear showed higher sensitivity (72.6%), specificity (96.1%), and positive predictability (89.8%), and lower negative predictability (88.0%), and false negativity (27.4%). The positive predictability was significantly higher (95% C.I.: 1.3-13.7). CONCLUSION: The positive predictability was significantly improved in the Liquid Pap smear. Therefore, the Liquid Pap smear is a more useful method in screening of cervical cancer.
Biopsy ; Female ; Humans ; Mass Screening ; Sensitivity and Specificity ; Uterine Cervical Neoplasms

OBJECTIVES: The purpose of this study was to examine the influence of self-esteem and social support on the depression stati of some clinical nurses, and propose basic data for a depression care program. METHODS: Between March 31 and April 5 at 2006, a self-reporting questionnaire survey was administered to 200 nurses at a general hospital located in Gyeonggi-do. The Beck's Depression Inventory (BDI) was used to assess the subjects'depression stati. RESULTS: The average BDI score of the clinical nurses was 8.9+/-7.5, with 59% belonging to the normal category, 28% having mild depressive symptoms, and 13% with a moderate degree of depressive symptoms. The degree of depression was significantly increased in the clinical nurses with a lower self-esteem and less social support. The degree of depression was significantly increased in the clinical nurses with a lower self-esteem and less social support. According to a multivariate regression analysis, a significant association was found between self-esteem and social support in relation to the depression of clinical nurses. The effect of social support was found to not be significant in cases where the self-esteem was high: however, depression was significantly influenced by social support in cases where the self-esteem was low. CONCLUSION: Self-esteem and social support were observed to influence the depression stati of clinical nurses. Therefore, it is suggested that an increase in depression management programs is required to create systematic management to maintain an atmosphere of high self-esteem and close relationships to manage the depression of clinical nurses.
Atmosphere ; Depression* ; Gyeonggi-do ; Hospitals, General ; Questionnaires

BACKGROUND: Community-acquired pneumonia is one of the main causes of hospitalization and death, especially in elderly patients. There have been many studies on prognosis for community-acquired pneumonia, but few in Korea. We sought to identify characteristics on admission predicting mortality in elderly patients hospitalized with community-acquired pneumonia and to compare mortality rates by PORT score with PORT study's ones. METHODS: We performed a retrospective study of 267 patients aged 65 years and over admitted with community- acquired pneumonia from January 2000 to December 2002. We reviewed demographic, clinical, laboratory, microbiological and radiologic data and identified independent factors associated with the mortality using logistic regression analysis. We classified patients into risk classes by PORT score and calculated the mortality rate. RESULTS: Among of 267 patients, 48 (18.0%) died. We identified six independent predictors of mortality; male (OR, 2,496; 95% CI, 1,012~6,153), lung cancer (OR, 3,409; 95% CI, 1,302~8,920), general weakness (OR, 5.218; 95% CI, 2,140~12,718), unable to walk (OR, 9,232; 95% CI, 2,228~38,257), BUN > or =30 mg/dL (OR, 3,327; 95% CI, 1.072~10.327), albumin <3 g/dL (OR, 3,219; 95% CI, 1,351~7,670) and pleural effusion (OR, 3.135; 95% CI, 1,052~9,342). Mortality rates of risk class II-V by PORT score were 6.7%, 9.5%, 30.4% and 34.4%, respectively. CONCLUSION: There were factors that were associated with mortality in elderly patients hospitalized with community-acquired pneumonia.
Aged* ; Hospitalization ; Humans ; Korea ; Logistic Models ; Lung Neoplasms ; Male ; Mortality* ; Pleural Effusion ; Pneumonia* ; Prognosis ; Retrospective Studies

No abstract available.
Nicotine* ; Periodontal Ligament*

Schwannomas are benign tumors that arise from the neural sheath of Schwann cells. Renal schwannomas are extremely rare and are commonly misdiagnosed as renal cell carcinoma, which typically results in a radical nephrectomy. We present a case of a renal schwannoma that mimics a renal pelvis tumor.
Carcinoma, Renal Cell ; Kidney ; Kidney Pelvis ; Nephrectomy ; Neurilemmoma ; Schwann Cells

OBJECTIVES: This study sought to evaluate trabecular changes in the mandible using fractal analysis and to explain the transient osteopenia related to rapid orthodontic tooth movement after orthognathic surgery. MATERIALS AND METHODS: Panoramic radiographs were taken of 26 patients who underwent bilateral sagittal split ramus osteotomy. Radiographs taken before the surgery and 1 month after surgery were overlapped, and 40x40 pixel square regions of interest were selected near the mandibular canines and 1st molars. After the image processing procedure, the fractal dimension was calculated using the box-counting method. RESULTS: Fractal dimension after orthognathic surgery decreased in a statistically significant manner (P<0.05). The change in fractal dimension on the canine side had greater statistical significance as compared to that seen on the 1st molar side. CONCLUSION: This study found that bone density decreases after orthognathic surgery due to transient osteopenia related to the regional acceleratory phenomenon. This result can provide a guide to evaluating orthodontic tooth movement after orthognathic surgery.
Bone Density ; Bone Diseases, Metabolic ; Fractals ; Humans ; Mandible ; Molar ; Orthognathic Surgery ; Osteotomy, Sagittal Split Ramus ; Tooth Movement

OBJECTIVE: We have developed breast tumor image retrieval system using content-based retrieval method. It compares the breast tumor image with Fibrocystic Change images, Ductal Carcinoma in Situ images and Invasive Ductal Carcinoma images and find most similar one. Since the final diagnosis for breast tumor image is done only by pathologist manually, this system can provide the objectivity and the reproducibility for determining and diagnosing the breast tumor. METHODS: The breast tumor image features used in the content-based image retrieval are color feature, texture feature and texture features of wavelet transformed images. And the system can be accessed through the internet. We used Windows 2003 as an operating system, Internet Information Server 6.0 as Web a server and ms-sql server 2000 as a database server. Also we use ActiveX Data Object to connect database easily. RESULT: We evaluated the recall and precision performance of the system according to the combinations of feature types and usage of partial or whole image. Results showed that the use of multiple features and whole image gave consistently higher rates compared to the use of single feature and partial image. CONCLUSION: This retrieval system can help pathologist determine the type of breast tumor more efficiently. Also it is working based on the internet, we can use it for researching and teaching in pathology later.
Breast Neoplasms* ; Breast* ; Carcinoma, Ductal ; Carcinoma, Intraductal, Noninfiltrating ; Diagnosis ; Internet* ; Pathology ; Wavelet Analysis