Anti-obesity and LDL-cholesterol lowering effects of silkworm hemolymph in C57BL/6N mice fed high fat diet / 한국영양학회지

PURPOSE: Obesity, a worldwide epidemic, is associated with insulin resistance, hyperlipidemia, hypertension, cardiovascular disease, and certain cancers. Many strategies, including natural alternative anti-obesity agents, are used widely to prevent obesity. This study examined the effects of silkworm hemolymph on the weight control of C57BL/6N mice fed with a high-fat diet. METHODS: The mice were divided into five groups: normal group (N), high-fat diet group (HFC), high-fat diet and silkworm hemolymph (at dose of 1 mL/kg BW (HFS-1), 5 mL/kg BW (HFS-5) and 10 mL/kg (HFS-10) for 12 weeks. RESULTS: After 12 weeks treatment, the administration of silkworm hemolymph decreased the final body weight significantly along with a decrease in the weights of epididymal fat and total fat. The plasma LDL-cholesterol concentration was significantly lower in the HFS-1, HFS-5, and HFS-10 groups than in the HFC group. In addition, the leptin level of the HFS groups was significantly lower than those of the HFC group without a change in the plasma insulin concentration. CONCLUSION: These findings suggest that the silkworm hemolymph may have the potential to prevent obesity.

Potassium intake of Korean adults: Based on 2007~2010 Korea National Health and Nutrition Examination Survey / 한국영양학회지

PURPOSE: The purpose of this study was to evaluate the dietary potassium intake, Na/K intake molar ratio, consumption of 18 food groups, and foods contributing to potassium intake of Korean adults as well as the relationships among quartile of potassium intake level and blood pressure, blood biochemical index. METHODS: This study was conducted using the Korea National Health and Nutrition Examination Survey, 2007~2010. The total number of subjects was 20,291. All analyses were conducted using a survey weighting to account for the complex survey design. RESULTS: Overall average intakes of potassium were 2,934.7, 3,070.6, 3,078.1, and 3,232.0 mg/day, and they significantly increased by year in Korean adults. The average dietary potassium intake was close to adequate intake (AI), whereas that of women was considerably lower than the AI. The Na/K intake molar ratio in males (2.89~3.23) was higher than in females (2.62~2.95). The major food groups contributing to potassium intake were vegetables, cereals, and fruits/meats. The two major foods contributing to potassium intake were polished rice and cabbage kimchi. The rankings of food source were as follows; polished rice > cabbage kimchi > potato > oriental melon > sweet potato > seaweed > radish > apple > black soybean. In 50~64 year old females, systolic blood pressure (SBP) significantly decreased (p < 0.01) and HDL-cholesterol significantly increased (p < 0.05) as potassium intake increased. Triglyceride (TG) was significantly higher in the other quartile of potassium intake level than in the first quartile (p < 0.05). CONCLUSION: In conclusion, our study suggests the need for an appropriate set of dietary reference intakes according to caloric intake by sex and age groups and for development of eating patterns to increase potassium intake and decrease sodium intake.

1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (EC-18) Modulates Th2 Immunity through Attenuation of IL-4 Expression

Controlling balance between T-helper type 1 (Th1) and T-helper type 2 (Th2) plays a pivotal role in maintaining the biological rhythm of Th1/Th2 and circumventing diseases caused by Th1/Th2 imbalance. Interleukin 4 (IL-4) is a Th2-type cytokine and often associated with hypersensitivity-related diseases such as atopic dermatitis and allergies when overexpressed. In this study, we have tried to elucidate the function of 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (EC-18) as an essential modulator of Th1/Th2 balance. EC-18 has showed an inhibitory effect on the production of IL-4 in a dose-dependent manner. RT-PCR analysis has proved EC-18 affect the transcription of IL-4. By analyzing the phosphorylation status of Signal transducer and activator of transcription 6 (STAT6), which is a transcriptional activator of IL-4 expression, we discovered that EC-18 induced the decrease of STAT6 activity in several stimulated cell lines, which was also showed in STAT6 reporter analysis. Co-treatment of EC-18 significantly weakened atopy-like phenotypes in mice treated with an allergen. Collectively, our results suggest that EC-18 is a potent Th2 modulating factor by regulating the transcription of IL-4 via STAT6 modulation, and could be developed for immune-modulatory therapeutics.

Protective Effect of Kefir Grain Against Dextran Sodium Sulfate-Induced Colitis in Rats

Probiotics have emerged as a potential treatment modality for numerous gastrointestinal disorders, including IBD. However, few probiotics have undergone appropriate preclinical screening in vivo. Kefir is considered a probiotic, benefiting the host through its effects in the intestinal tract. Despite numerous studies examining the action of probiotics on the host organism, few have analyzed the effects on intestinal environment. We assessed the protective effect of kefir for three weeks before inducing colitis with 2% dextran sodium sulfate for five days. The DSS loads were similar in all DSS treatment group. The results of the experiment are as follows. Food intake and FER of experimental groups were not significantly different each other, but water consumption tended to be higher in all DSS treatment groups as compared with the normal control. And visual inspection of feces revealed mild diarrhea in rat given 2% DSS. The anti-inflammatory activity of kefir was determined by myeloperoxidase activity during the DSS treatment, and there was no significant difference in any group. The levels of thiobarbituric acid reactive substances (TBARS) as a colonic lipid peroxidation were significantly lower in the kefir intake groups than in rats treated with 2% DSS alone. The DNA % in tail and tail moment values as a DNA damage level of the blood lymphocytes in kefir intake groups tended to be lower than 2% DSS treatment alone, especially tail lengths were significantly diminished. According to the colonic histopathological assay, there were a severe inflammation of lamina propria and submucosa and mild edema in mucosa and sub mucosa in DSS alone treated group. We found a slight regenerative change in kefir treatment groups. In our experiments, this means that ulcerative colitis related to oxidative injury might be prevented by kefir as a probiotic. Further studies of the potential benefits of kefir as a probiotic in inflammatory condition are encouraged.

Comparison of Skin dose Measurement Using Glass Dosimeter and Diode for Breast Cancer Patients / 의학물리

The purpose of this study was to measure the skin dose using the glass dosimeter and diode and to compare those measurements to the planned skin dose from the treatment planning system. For the reproducibility of the glass dosimeter (ASAHI TECHNO GLASS CIRPORATION, Japan), the same dose was irradiated to 40 glass dosimeters three times, among which 28 with the reproducibility within 3% were selected for the use of this study. For each of 27 breast cancer patients, the glass dosimeters and diodes were attached to 4 different locations on the skin to measure the dose during treatment. All the patients received one fraction of 180 cGy each. The maximum difference of measurements between the glass dosimeter and diode at the same location was 3.2%. Comparing with the planned skin dose from the treatment planning system (Eclipse v6.5, Varian, USA), the dose measured by the glass dosimeter and the diodeshowed on an average 3.4% and 2.3% difference, respectively. The measured doses were always less than the planned skin dose. This may be due to the specific errors of both detectors. Also, the difference may be caused by the fact that since the skin where the detectors were attached is pretty moveable, it was not fix the detectors on the skin.

Clinical Implementation of an Eye Fixing and Monitoring System with Head Mount Display / 의학물리

A system to non-invasively fix and monitor eye by a head mounted display (HMD) with a CCD camera for stereotactic radiotherapy (SRS) of uveal melanoma has been developed and implemented clinically. The eye fixing and monitoring system consists of a HMD showing patient a screen for fixing eyeball, a CCD camera monitoring patient' s eyeball, and an immobilization mask. At first, patient' s head was immobilized with a mask. Then, patient was instructed to wear HMD, to which CCD camera was attached, on the mask and see the given reference point on its screen. While patient stared at the given point in order to fix eyeball, the camera monitored its motion. Four volunteers and one patient of uveal melanoma for SRS came into this study. For the volunteers, setup errors and the motion of eyeball were analyzed. For the patient, CT scans were performed, with patient' s wearing HMD and fixing the eye to the given point. To treat patient under the same condition, daily CT scans were also performed before every treatment and the motion of lens was compared to the planning CT. Setup errors for four volunteers were within 1 mm and the motion of eyeball was fixed within the clinically acceptable ranges. For the patient with uveal melanoma, the motion of lens was fixed within 2 mm from daily CT scans. An eye fixing and monitoring system allowed immobilizing patient as well as monitoring eyeball and was successfully implemented in the treatment of uveal melanoma for SRS.

Effectiveness of Breath Hold with a ABC for SRS of Lung Cancer

PURPOSE: It is very important to remove or to reduce the effect of organ motion due to respiration in stereotatic radiosurgery of lung. This study reports the effectiveness of the breath hold technique with a ABC for reducing the breathing effect. MATERIALS AND METHODS: Whole body stereotactic frame (Elekta, Sweden) was used for lung SRS. Patients who have tumor motion range larger than 10 mm from fluoroscopic observation were selected to apply a ABC. Seventeen patients were enrolled in this study. Passive breath hold is possible with our ABC. Automatic breath hold was set at 80% of deep inspiration. Breath hold time was 25~30 seconds depending on the patients. Three consecutive CT scans were performed as indicated in Asan Medical Center SRS procedure for each patients. Lung volume and PTV differences between with breath hold and free breath were examined for 5 patients. RESULTS: The breath hold technique with ABC could be applied for 15 patients. Inter-, intra-treatment organ motion with ABC showed 1.5 mm, while it was 2.3 mm with abdomen compress. When with breath hold technique, PTV and CTV was reduced 33.7% and 45.4%, respectively, and lung volume was increased 32.3 % compared to conventional SRS method. CONCLUSION: Better target localization could be achieved with breath hold technique in lung SRS. Tumor motion could be minimized and relative lung volume irradiation could be reduced

Feasibility Study of the Real-Time IMRT Dosimetry Using a Scintillation Screen / 대한방사선종양학회지

PURPOSE: To study the feasibility of verifying real-time 2-D dose distribution measurement system with the scintillation screen for the quality assurance. MATERIALS AND METHODS: The water phantom consisted of a scintillation screen (LANEX fast screen, Kodak, USA) that was axially located in the middle of an acrylic cylinder with a diameter of 25 cm. The charge-coupled device (CCD) camera was attached to the phantom in order to capture the visible light from the scintillation screen. To observe the dose distribution in real time, the intensity of the light from the scintillator was converted to a dosage. The isodose contours of the calculations from RTP and those of the measurements using the scintillation screen were compared for the arc therapy and the intensity modulated radiation therapy (IMRT). RESULTS: The kernel, expressed as a multiplication of two error functions, was obtained in order to correct the sensitivity of the CCD of the camera and the scintillation screen. When comparing the calculated isodose and measured isodose, a discrepancy of less than 8 mm in the high dose region was observed. CONCLUSIONS: Using the 2-D dosimetry system, the relationship between the light and the dosage could be found, and real-time verification of the dose distribution was feasible.

Optimum Segment Size for Intensity Modulated Radiation Therapy of Lung Region

PURPOSE: In general, it is possible to generate better leaf sequencing from the ideal fluence map or dose distribution close to the optimized results of the radiation treatment planning (RTP) system, from the filed smaller segment size in Intensity modulated radiation therapy (IMRT). Conversely, an intra-treatment organ motion issue, which prevents the smallest segment size from being chosen, always exists. Furthermore, the question has been raised regarding the proper target margin for IMRT cases with a moving target, as the field itself moves while the target moves, unlike traditional static fields. In this study, the effects of intra-treatment target motion on the segment size have been examined. MATERIALS AND METHODS: Various sizes of rectangular patterns were designed for an IMRT fluence map. A leaf sequence was generated using the step and shoot beam delivery method. The intensity ratios between adjacent segments were 0.2, 0.4 and 0.8. The range of target motion was assumed to be +/-0.3~2.0 cm, in a sinusoidal shape. The dynamic leaf motion that reflected the target motion was calculated to simulate the motion. Film dosimetry was performed to analyze the motion effects. RESULTS: The intensity ratios of the adjacent segments were degraded in all cases. The dose distribution with segment sizes less than half the breathing amplitude showed a significantly degraded intensity map. With a beam irradiation time for a segment greater than two breathing cycles, the dose distribution around the target margin showed a similar tendency as the static fields. CONCLUSION: The minimum size of IMRT segments in the fluence map should be chosen taking the intra-treatment organ motion into consideration. The dose distribution with segment sizes less than half the breathing amplitude was degraded significantly in the intensity map. With a beam irradiation time for a segment greater than two breathing cycles, the target margin can be defined as the same as for a conventional static field

Partial Block Technique for Radiation Therapy of Lung Cancer with Dynamic Multi-leaf Collimator

PURPOSE: A spinal cord partial block technique (PBT) with dynamic multileaf collimator (dMLC) for the reduction of the spinal cord dose while keeping the tumor dose unchanged has been developed and its effectiveness has been examined. MATERIALS AND METHODS: Conventional 3-D conformal therapy treatment plan is deigned prior to the PBT application. Beam parameters such as, number of beams, beam directions were determined during 3-D conformal therapy planning process. The shape and the weight of the partial block for optimizing the dose distribution are designed with the forward intensity modulated radiation therapy (fIMRT). Eight cases of lung cancer, in which it was found to be impossible to deliver enough doses to targets with the conventional technique because the doses of the normal lungs or the spinal cords were over the tolerance limit, are used to verify the usefulness of this technique. Comparison of the dose volume histogram (DVH) is performed to compare the treatment plan. RESULTS: PBT plan cauld reduce the maximum dose to the spinal cord up to 29.7% and the mean dose to the lungs up to 11.1%. CONCLUSION: All of the cases showed that the PBT plans are better than the conventional 3-D plans and the spinal cord doses or the normal lung doses can be reduced to tolerance limit

Beam Shaping by Independent Jaw Closure in Stereotactic Radiotherapy / 대한방사선종양학회지

INTRODUCTION: Stereotactic radiation therapy (SRT) can deliver highly focused radiation to a small and spherical target lesion with very high degree of mechanical accuracy. For non-spherical and large lesions, however, inclusion of the neighboring normal structures within the high dose radiation volume is inevitable in SRT. This is to report the beam shaping using the partial closure of the independent jaw in SRT and the verification of dose calculation and the dose display using a home-made soft ware. MATERIALS & METHODS: Authors adopted the idea to partially close one or more independent collimator jaw(s) in addition to the circular collimator cones to shield the neighboring normal structures while keeping the target lesion within the radiation beam field at all angles along the arc trajectory. The output factors (OF's) and the tissue-maximum ratios (TMR's) were measured using the micro ion chamber in the water phantom dosimetry system, and were compared with the theoretical calculations. A film dosimetry procedure was performed to obtain the depth dose profiles at 5 cm, and they were also compared with the theoretical calculations, where the radiation dose would depend on the actual area of irradiation. Authors incorporated this algorithm into the home-made SRT software for the isodose calculation and display, and was tried on an example case with single brain metastasis. The dose-volume histograms (DVH's) of the planning target volume (PTV) and the normal brain derived by the control plan were reciprocally compared with those derived by the plan using the same arc arrangement plus the independent collimator jaw closure. RESULTS: When using 5.0 cm diameter collimator, the measurements of the OF's and the TMR's with one independent jaw set at 30 mm (unblocked), 15.5 mm, 8.6 mm, and 0 mm from the central beam axis showed good correlation to the theoretical calculation within 0.5% and 0.3% error range. The dose profiles at 5 cm depth obtained by the film dosimetry also showed very good correlation to the theoretical calculations. The isodose profiles obtained on the home-made software demonstrated a slightly more conformal dose distribution around the target lesion by using the independent jaw closure, where the DVH's of the PTV were almost equivalent on the two plans, while the DVH's for the normal brain showed that less volume of the normal brain receiving high radiation dose by using this modification than the control plan employing the circular collimator cone only. CONCLUSION: With the beam shaping modification using the independent jaw closure, authors have realized wider clinical application of SRT with more conformal dose planning. Authors believe that SRT, with beam shaping ideas and efforts, should no longer be limited to the small spherical lesions, but be more widely applied to rather irregularly shaped tumors in the intracranial and the head and neck regions.