• Journal of Radiation Protection and Research
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• v.27 no.1
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• pp.1-10
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• 2002

High energy photon beams from medical linear accelerators produce large scattered radiation by various components of the treatment head, collimator and walls or objects in the treatment room including the patient. These scattered radiation do not provide therapeutic dose and are considered a hazard from the radiation safety perspective. Scattered dose of therapeutic high energy radiation beams are contributed significant unwanted dose to the patient. ICRP take the position that a dose of 500mGy may cause abortion at any stage of pregnancy and that radiation detriment to the fetus includes risk of mental retardation with a possible threshold in the dose response relationship around 100 mGy for the gestational period. The ICRP principle of as low as reasonably achievable (ALARA) was recommended for protection of occupation upon the linear no-threshold dose response hypothesis for cancer induction. We suggest this ALARA principle be applied to the fetus and testicle in therapeutic treatment. Radiation dose outside a photon treatment filed is mostly due to scattered photons. This scattered dose is a function of the distance from the beam edge, treatment geometry, primary photon energy, and depth in the patient. The need for effective shielding of the fetus and testicle is reinforced when young patients ate treated with external beam radiation therapy and then shielding designed to reduce the scattered photon dose to normal organs have to considered. Irradiation was performed in phantom using high energy photon beams produced by a Varian 2100C/D medical linear accelerator (Varian Oncology Systems, Palo Alto, CA) located at the Yonsei Cancer Center. The composite phantom used was comprised of a commercially available anthropomorphic Rando phantom (Phantom Laboratory Inc., Salem, YN) and a rectangular solid polystyrene phantom of dimensions $30cm{\times}30cm{\times}20cm$. the anthropomorphic Rando phantom represents an average man made from tissue equivalent materials that is transected into transverse 36 slices of 2.5cm thickness. Photon dose was measured using a Capintec PR-06C ionization chamber with Capintec 192 electrometer (Capintec Inc., Ramsey, NJ), TLD( VICTOREEN 5000. LiF) and film dosimetry V-Omat, Kodak). In case of fetus, the dosimeter was placed at a depth of loom in this phantom at 100cm source to axis distance and located centrally 15cm from the inferior edge of the $30cm{\times}30cm^2$ x-ray beam irradiating the Rando phantom chest wall. A acryl bridge of size $40cm{\times}40cm^2$ and a clear space of about 20 cm was fabricated and placed on top of the rectangular polystyrene phantom representing the abdomen of the patient. The leaf pot for testicle shielding was made as various shape, sizes, thickness and supporting stand. The scattered photon with and without shielding were measured at the representative position of the fetus and testicle. Measurement of radiation scattered dose outside fields and critical organs, like fetus position and testicle region, from chest or pelvic irradiation by large fie]d of high energy radiation beam was performed using an ionization chamber and film dosimetry. The scattered doses outside field were measured 5 - 10% of maximum doses in fields and exponentially decrease from field margins. The scattered photon dose received the fetus and testicle from thorax field irradiation was measured about 1 mGy/Gy of photon treatment dose. Shielding construction to reduce this scattered dose was investigated using lead sheet and blocks. Lead pot shield for testicle reduced the scatter dose under 10 mGy when photon beam of 60 Gy was irradiated in abdomen region. The scattered photon dose is reduced when the lead shield was used while the no significant reduction of scattered photon dose was observed and 2-3 mm lead sheets refuted the skin dose under 80% and almost electron contamination. The results indicate that it was possible to improve shielding to reduce scattered photon for fetus and testicle when a young patients were treated with a high energy photon beam.

• Radiation Oncology Journal
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• v.17 no.2
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• pp.113-119
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• 1999

Purpose : To evaluate possible acute toxicity and early response of concurrent radiation therapy and low dose daily cisplatin as a radiosensitizer in patients with locally advanced uterine cervical carcinomas. Materials and Method : From December 1996 to January 1999, 38 previously untreated Patients with locally advanced squamous cell carcinoma of the uterine cervix (from stage IIB to stage IIIB) were treated at Inha University Hospital. All patients underwent standard pretreatment staging Procedures after the initial evaluation by gynecologists and radiation oncologists. Sixteen Patients with huge cervical mass (>4 cm) were submitted to the group treated with concurrent radiation therapy and low dose daily cisplatin while the remainder was treated with radiation therapy alone. Radiation therapy consisted of 4500 cGy external beam irradiation to whole pelvis (midline block after 3000 cGy), 900$\~$1000 cGy boost to involved parametrium, and high dose-rate intracavitary brachytherapy (a total dose of 3000$\~$3500 cGy/500 cGy per fraction to point A, twice per week). In the group treated with low dose cisplatin concurrently, 10 mg of daily intravenous cisplatin was given from the 1st day of radiation therapy to the 20th day of radiation therapy. Acute toxicity was measured according to expanded common toxicity criteria of the NCI (C) Clinical Trials. Early response data were analyzed at minimum 4 weeks' follow-up after completion of the treatment protocol. Results: Hematolgic toxici쇼 was more prominent in patients treated with radiation therapy and cisplatin. Six of 16 patients (37.5$\~$) treated with radiation therapy and cisplatin and one of 22 patients (4.5$\~$) treated with radiation therapy alone experienced grade 3 leukopenia. In Fisher's exact test, there was statistically significant difference between two groups regarding leukopenia (P=0.030). There was no apparent difference in the frequency of gastrointestinal and genitourinary toxicity between two groups (P=0.066). Three of 16 patients (18.7$\~$) treated with radiation therapy and cisplatin and two of 22 patients (9.1$\~$) treated with radiation therapy alone experienced more than 5 kg weight loss during the treatment. There was no statistically significant difference on weight loss between two groups (P=0.63). Two patients on each group were not evaluable for the early response because of incomplete treatment. The complete response rate at four weeks' follow-up was 80$\~$(16/20) for the radiation therapy alone group and 78$\~$ (11/14) for the radiation therapy and cisplatin group. There was no statistically significant difference in early response between two treatment groups (P=0.126). Conclusion : This study led to the conclusion that the hematologic toxicity from the treatment with concurrent radiation therapy and low dose daily cisplatin seems to be more prominent than that from the treatment of radiation therapy alone. There was no grade 4 hematologic toxicity or mortality in both groups. The hematologic toxicity in both treatment groups seems to be well managable modically. Since the risk factors were not balanced between two treatment groups, the direct comparison of early response of both groups was not possible. However, preliminary results regarding early response for patients with bulky cervical tumor mass treated with radiation therapy and low dose daily cisplatin was encouraging. Longer follow-up is necessary to evaluate the survival data. A phase III study is needed to evaluate the efficacy of concurrent daily low dose cisplatin with radiation therapy in bulky cervical cancer.

• Journal of Chest Surgery
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• v.37 no.10
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• pp.845-855
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• 2004

Background: No general consensus has been available regarding the necessity of postoperative radiation therapy (PORT) and its optimal techniques in the patients with chest wall invasion (pT3cw) and node negative (N0) non-small cell lung cancer (NSCLC). We did retrospective analyses on the pT3cwN0 NSCLC patients who received PORT because of presumed inadequate resection margin on surgical findings. And we compared them with the pT3cwN0 NSCLC patients who did not received PORT during the same period. Material and Method: From Aug. of 1994 till June of 2002, 22 pT3cwN0 NSCLC patients received PORT-PORT (＋) group- and 16 pT3cwN0 NSCLC patients had no PORT-PORT (-) group. The radiation target volume for PORT (＋) group was confined to the tumor bed plus the immediate adjacent tissue only, and no regional lymphatics were included. The prognostic factors for all patients were analyzed and survival rates, failure patterns were compared with two groups. Result: Age, tumor size, depth of chest wall invasion, postoperative mobidities were greater in PORT (-) group than PORT (＋) group. In PORT (-) group, four patients who were consulted for PORT did not receive the PORT because of self refusal (3 patients) and delay in the wound repair (1 patient). For all patients, overall survival (OS), disease-free survival (DFS), loco-regional recurrence-free survival (LRFS), and distant metastases-free survival (DMFS) rates at 5 years were 35.3%, 30.3%, 80.9%, 36.3%. In univariate and multivariate analysis, only PORT significantly affect the survival. The 5 year as rates were 43.3% in the PORT (＋) group and 25.0% in PORT (-) group (p=0.03). DFS, LRFS, DMFS rates were 36.9%, 84.9%, 43.1 % in PORT (＋) group and 18.8%, 79.4%, 21.9% in PORT(-) group respectively. Three patients in PORT (-) group died of intercurrent disease without the evidence of recurrence. Few suffered from acute and late radiation side effects, all of which were RTOG grade 2 or lower. Conclusion: The strategy of adding PORT to surgery to improve the probability not only of local control but also of survival could be justified, considering that local control was the most important component in the successful treatment of pT3cw NSCLC patients, especially when the resection margin was not adequate. Authors were successful in the marked reduction of the incidence as well as the severity of the acute and late side effects of PORT, without taking too high risk of the regional failures by eliminating the regional lymphatics from the radiation target volume.

• Pediatric Infection and Vaccine
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• v.30 no.2
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• pp.73-83
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• 2023

Purpose: This study aimed to investigate the viral load dynamics in children with underlying malignancies diagnosed with symptomatic coronavirus disease 2019 (COVID-19). Methods: This was a retrospective longitudinal cohort study of patients <19 years old with underlying hemato-oncologic malignancies that were diagnosed with their first symptomatic severe acute respiratory syndrome coronavirus 2 polymerase chain reaction (PCR)-confirmed COVID-19 infection during March 1 to August 30, 2022. Review of electronic medical records and telephone surveys were undertaken to assess the clinical presentations and transmission route of the patients. Thresholds of negligible likelihood of infectious virus was defined as E gene reverse transcription (RT)-PCR cycle threshold (Ct) value ≥25. Results: During the 6-month study period, a total of 43 children with 44 episodes of COVID-19 were included. Of the 44 episodes, the median age of the patients included was 8 years old (interquartile range [IQR], 4.9-10.5), and the most common underlying disease was acute lymphoid leukemia (n=30, 68.2%), followed by patients post-hematopoietic stem cell transplantation (n=8, 18.2%). Majority of the patients had mild COVID-19 (n=32, 72.7%), and three patients (7.0%) had severe/critical COVID-19. Furthermore, 2.3% (n=1) died of COVID-19 associated acute respiratory distress syndrome. The largest percentage of the patients showed E gene RT-PCR Ct value ≥25 between 15-21 days (n=13, 39.4%), followed by 22-28 days (n=10, 30.3%). In 15.2% (n=5), E gene RT-PCR Ct value remained <25 beyond 28 days after initial positive PCR. Refractory malignancy status (β, 67.0; 95% confidence interval, 7.0-17.0; P=0.030) was significantly associated with prolonged duration of E gene RT-PCR <25. A patient with prolonged duration of E gene RT-PCR Ct value <25 was suspected to have infectivity shown by the transmission of the virus to his mother at day 86 after his initial positive test. Conclusions: Children that acquire symptomatic COVID-19 during refractory malignancy state are at a high risk for prolonged shedding warranting PCR-based transmission precautions in this cohort of patients.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.28 no.1
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• pp.70-79
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• 2024

Backgrounds/Aims: After pancreatoduodenectomy (PD), an early oral diet is recommended; however, the postoperative nutritional management of PD patients is known to be highly variable, with some centers still routinely providing parenteral nutrition (PN). Some patients who receive PN experience clinically significant complications, underscoring its judicious use. Using a large cohort, this study aimed to determine the proportion of PD patients who received postoperative nutritional support (NS), describe the nature of this support, and investigate whether receiving PN correlated with adverse perioperative outcomes. Methods: Data were extracted from the Recurrence After Whipple's study, a retrospective multicenter study of PD outcomes. Results: In total, 1,323 patients (89%) had data on their postoperative NS status available. Of these, 45% received postoperative NS, which was "enteral only," "parenteral only," and "enteral and parenteral" in 44%, 35%, and 21% of cases, respectively. Body mass index < 18.5 kg/m² (p = 0.03), absence of preoperative biliary stenting (p = 0.009), and serum albumin < 36 g/L (p = 0.009) all correlated with receiving postoperative NS. Among those who did not develop a serious postoperative complication, i.e., those who had a relatively uneventful recovery, 20% received PN. Conclusions: A considerable number of patients who had an uneventful recovery received PN. PN is not without risk, and should be reserved for those who are unable to take an oral diet. PD patients should undergo pre- and postoperative assessment by nutrition professionals to ensure they are managed appropriately, and to optimize perioperative outcomes.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.617-637
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• 1996

Occupational dermatosis is one of the most prevalent occupational disorders. However, the extent of the occupational dermatoses including incidences and prevalencies of each disease entity, and etiologic materials are not yet welt stated in Korea. Authors reviewed the literatures on the statistic data and reports on the occupational dermatoses, and surveyed on the occupational dermatoses in two factories, and surveyed the physicians responsible to the occupational dermatoses with formed questionnaire. The results are as follows; 1. Among medical journals published since 1964, there were 31 articles on the occupational dermatoses. Of 31 articles, 18 were case reports and all others were review articles. Of 18 case reports, 9 were epidemiologic survey. The Workers' Periodic Health Examinations revealed that prevalence of the occupational dermatoses was highest(4.36 per 10,000 workers) in 1974, but number of the cases reported were decreased sharply since 1978 with some tendency to increase since 1981. There were 2,240 reported cases of occupational dermatoses between 1966 and 1992, which is 1.90% of all the reported occupational diseases. Skin infection and injuries due to chemicals were most frequent and there were 6 cases of skin cancer. 2. In an epidemiological survey on the dermatoses among 995 workers in a metal product manufacturing factory and 225 workers in a coal chemical factory, there were 794 with dermatomycosis, 296 workers with acne, 130 workers with scar, 123 workers with deformity of toe nails. Scars, photosensitivity dermatitis, deformity of finger and toe nails, and acne were more prevalent in the metal product manufacturing factory(p<0.05). In the metal prouct manufacturing factory, workers treating organic solvents and oils had more dermatoses than those without treating the materials(p<0.05). On the skin patch performed on 16 workers in the metal product manufacturing factory, there were 8 cases of irritation dermatitis and 5 cases of contact dermatitis. Prevalence of contact dermatitis in the metal product manufacturing factory was 1.3%. 3. On the questionnaire survey, 34 dermatologists, 29 doctors of preventive medicine, and 22 family physician replied. The proportion of occupational etiology among all dermatoses assumed by the physicians were below 9%, and the most important occupational dermatosis in Korea was contact dermatitis. Main etiologic materials related to the occupational dermatosis were organic solvent, acid and alkali, and metals. The reason for the scarcity of report of occupational dermatoses were difficulty in diagnosis and physician's ignorance of the occupational etiology. They replied that to prevent the occupational dermatoses in the workplace, the use of protective devices was most important, and development of diagnostic criteria on the occupational dermatoses is urgent. Above results shows us that there is many workers with occupational dermatoses, but they are mostly unreported. Measures to prevent and manage the occupational dermatoses are not satisfactory at present. Hence, authors suggest measures for the precise diagnosis, report and prevention of the occupational dermatoses. a. Dermatologist, preventive physician, and industrial hygienist should work as a team to examine the high risk group and establish the preventive measures. b. Disease entities, diagnostic criteria of occupational dermatoses should be listed, criteria for the compensation and job fitting at recruitment should be established, and manual for the proper treatment and effective prevention of each occupational dermatosis should be developed. c. Patch test antigens against each occupational category should be developed and it should be available to any physicians responsible. d. To facilitate the diagnosis of occupational dermatoses by the doctors responsible for the Workersr Periodic Health Examination, development of standardized questionnaire, education on the techniques of the patch test, and cooperation with the dermatologist in diagnosis of occupational dermatoses is essential.

• Journal of Life Science
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• v.19 no.6
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• pp.735-743
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• 2009

The common word flavonoids is often used to classify a family of natural compounds, highly abundant in all higher plants, that have received significant therapeutic interest in recent years. Naringin is associated with a reduced risk of heart disease, neurodegenerative disease, cancer and other chronic diseases; however the molecular basis of this effect remains to be elucidated. Thus we attempted to elucidate the anti-allergic effect of Naringin in ovalbumin (OVA)-induced asthma model mice. The OVA-induced mice showed allergic reactions in the airways. These included an increase in the number of eosinophils in bronchoalveolar lavage (BAL) fluid, an increase in inflammatory cell infiltration into the lung around blood vessels and airways, airway luminal narrowing, and the development of airway hyper-responsiveness (AHR). The administration of Naringin before the last airway OVA challenge resulted in a significant inhibition of all asthmatic reactions. Accordingly, this study may provide evidence that Naringin plays a critical role in the amelioration of the pathogenetic process of asthma in mice. These findings provide new insight into the immunopharmacological role of Naringin in terms of its effects on asthma in mice.

• Journal of agricultural medicine and community health
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• v.39 no.3
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• pp.137-145
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• 2014

Objectives: Colonoscopy is a popular tool for screening for colon cancer throughout the world. The incidence of polypectomy and follow-up colonoscopy are persistently increasing but the studies about follow-up test after polypectomy are still lack of its domestic sources. This study is designed to look into the recurrence rate of colon polyps and risk factors after polypectomy. Methods: This is a retrospective study by reviewing medical charts of 147 patients who underwent polypectomy and follow-up colonoscopy from Jan. 2000 to Mar. 2008. The Kudo classification was used to describe the polyps found in the colonoscopy. The follow-up period was defined as the term between polypectomy and the first colonoscopy follow up. Results: Seventy six point two percent of the enrolled patient were male and the mean age was $56.5{\pm}8.1$. Mean follow-up period was $24.9{\pm}13.7$ (6 - 65) months. The cumulative recurrence rate of 1 year was 11.6%. The rate of 2 years was 36.7% and that of 3 years was 55.8%. The number of polyps was the factor which statistically showed significant relation of its recurrence rate. The histological morphology characteristic of polyps could be one independent factor which may be associated to the recurrence of polyps. Conclusions: The importance of colonoscopy follow up after polypectomy was clearly emphasized through the cumulative recurrence rate of 55.8%. Therefore, there is a need for more domestic studies with a large number of patients about the recurrence of polyps after polypectomy.

• Radiation Oncology Journal
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• v.18 no.1
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• pp.40-45
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• 2000

Purpose : To evaluate the histopathological prognostic factors, relapse pattern and survival in patients with endometrial carcinoma who were treated with surgery and postoperative adjuvant radiotherapy (RT). Methods and Materials : From September 1991 to December 1997, 27 patients with endometrial carcinoma treated with surgery and postoperative adjuvant RT at Asan Medical Center were entered in this study. Surgery was peformed with total abdominal hysterectomy in six, total abdominal hysterectomy with pelvic lymph node dissection in eight and radical hysterectomy in 13 patients. External RT of 50.4 Gy was done to all patients and among these, additional high dose rate vaginal vault irradiation of 20$\~$25 Gy with fractional dose of 4$\~$5 Gy was boosted In 16 patients. The patients were followed for 6$\~$95 months(median 30). Results : The number of patients according to FIGO stage were I 18 (67$\%$), II 1 ($4\%$) and III 7 ($26\%$). Patients with poor histologic grade, deep myometrial invasion, adnexal involvement, lymphovascular invasion showed more pelvic lymph node involvement, but no statistical significance was indicated. The 5 year overall and disease free survival were 100$\%$ and 76.8$\%$, respectively. Relapse sites were pelvic, para-aortic lymph node, and multiple metastases including lung, and no vaginal relapse was developed. Factors that were associated with disease free survival were FIGO stage (p=0.01), lymphovascular invasion (p=0.03), pelvic lymph node involvement (p=0.0001). There was only one Grade 1 rectal bleeding without moderate to severe complications. Conclusion : Postoperative adjuvant RT is considered to reduce the loco-regional failure, resulting the improvement of survival. The group of patients with the risk of vaginal failure without vaginal vault irradiation should be investigated according to stage and grade.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.199-205
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• 2006

Peroxisome proliferator activated receptor (PPAR)-$\alpha$ of three PPAR subtypes ($-\alpha,\;-\beta/-\gamma,\;-\delta$), which are members of the nuclear hormone receptor superfamily of ligand-activated transcription factors, plays a key role in lipoprotein and glucose homeostasis. A variation in the PPAR-a gene expression has been suggested to influence the development of metabolic syndrome through alterations in lipid concentrations. The aim of our study was to investigate the association between the PPAR-a and metabolic syndrome among South Korean. A total of 542 health screen examinees were enrolled in this study who were examined in Kosin University Gospel Hospital from December, 2004 to July, 2005. The height, weight, waist circumference, and systolic and diastolic blood pressure of the subjects were examined and fasting blood glucose, total cholesterol, HDL cholesterol, LDL cholesterol, triglyceride were measured by-sampling in venous blood. The metabolic syndrome was defined as the presence of three or more of the following : waist circumference men ${\geq}90cm$, women ${\geq}80cm$, blood pressure ${\geq}130/85mmHg$, fasting glucose ${\geq}110mg/dL$, HDL cholesterol men <40 mg/dL, women <50 mg/dL, triglyceride ${\geq}150mg/dL$. The blood pressure, fasting glucose, HDL cholesterol, triglyceride were evaluated by using the criteria of NECP ATP III and waist circumference was assessed by using the criteria of WHO Asia-Western Pacific. And the author compared the frequency of the PPAR-$\alpha$ mutation of L162V ($C{\rightarrow}G$ variant in exon 5) in a sample of 542 subjects with and without the metabolic syndrome by polymerase chain reaction allele-specific oligonucleotide (PCR-ASO) method. One (0.2%) hetero-isotype among high risk of metabolic syndrome was identified. The values of waist circumference, body mass index and low density lipoprotein cholesterol of the mutant were 100 cm, 28.6 $kg/m^2$ and 120 mg/dL, respectively. Although the author failed to see significant association between the presence of the PPAR-$\alpha$ L162V polymorphism and metabolic syndrome, one PPAR-$\alpha$ L162V polymorphism in metabolic syndrome patients was found.