• Korean Journal of Microbiology
• /
• v.49 no.1
• /
• pp.17-23
• /
• 2013

Candida biofilms are organized microbial communities growing on the surfaces of host tissues or indwelling medical devices, and the biofilms show enhanced resistance against the conventional antifungal agents. The roots of Coptidis chinensis have been widely used for medicinal purposes in East Asia. The present study was aimed to assess the effect of C. chinensis aqueous extract upon preformed biofilms of 10 clinical Candida albicans isolates and the antifungal activities which contribute to inhibit the C. albicans biofilm formation. Its effect on preformed biofilms was judged using XTT [2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide)] reduction assay, and metabolic activity of all tested strains was reduced significantly ($57.3{\pm}14.7%$) at $98{\mu}g/ml$ of the C. chinensis extract. The extract damaged the cell membrane of C. albicans which was analyzed by fluorescein diacetate and propidium iodide staining. The anticandidal activity was fungicidal, and the extract obstructed the adhesion of C. albicans biofilms to polystyrene surfaces, arrested C. albicans cells at $G_o/G_1$ as well, and reduced the growth of biofilms or budding yeasts finally. The data suggest that C. chinensis has multiple antifungal effects on target fungi resulting in preventing the formation of biofilms. Therefore, C. chinensis holds great promise for exploring antifungal agents from natural products in treating and eliminating biofilm-associated Candida infection.

• Journal of radiological science and technology
• /
• v.29 no.3
• /
• pp.125-132
• /
• 2006

The PET/CT scanner is an evolution in image technology. The two modalities are complementary with CT and PET images. The PET scan images are well known as low resolution anatomic landmak, but such problems may help with interpretation detailed anatomic framework such as that provided by CT scan. PET/CT offers some advantages-improved lesion localization and identification, more accurate tumor staging. etc. Conventional PET employs tranmission scan require around 4 min./bed position and 30 min. for whole body scan. But PET/CT scanner can reduced by 50% in whole body scan. Especially nowadays PET scanner LSO scintillator-based from BGO without septa and operate in 3-D acquisition mode with multidetectors CT. PET/CT scanner fusion problems solved through hardware rather than software. Such device provides with the capability to acquire accurately aligned anatomic and functional images from single scan. It is very important to effective detection from gamma ray source in PETdetector. And can be offer high quality diagnostic images. So we have study about detection processing of PET detector and high quality imaging process.

• Progress in Medical Physics
• /
• v.28 no.4
• /
• pp.190-196
• /
• 2017

For the $ViewRay^{(R)}$ system (ViewRay Inc., Cleveland, OH, USA) which is representative of magnetic resonance (MR) guided radiotherapy machine, it is important to evaluate effectiveness of AAPM's TG-51 protocol and the effect of the magnetic field on absolute dosimetry. In order to measure the absolute dose, MR-compatible chamber and water phantom system manufactured in this study were used. The materials of the water phantom system were plastic of polymethyl methacrylate (PMMA) and non-ferrous materials. Due to the inherent feature of the $ViewRay^{(R)}$, all Co-60 sources are not located at gantry angle of $0^{\circ}$ while being located at gantry angle of $90^{\circ}$. For this reason, absolute dosimetry was performed based on the measurements in solid water phantom (SWP) and water which determine the SWP to water correction factor. For evaluation of output constancy with gantry angle, measurements were made with ionization chamber inserted in cylindrical water-equivalent phantom. For measured doses in water, the values of dose deviation according to a reference dose of 200 cGy for Head 1, Head 2 and Head 3 were -0.27%, -0.45% and -0.22%, respectively. For measured doses in SWP, the values of dose deviation according to a reference dose of 200 cGy for Head 1, Head 2 and Head 3 were -1.91%, -2.07% and -1.84%, respectively. All values of dose measured in SWP tended to be less than those measured in water by -1.63%. With the reference gantry angles of $0^{\circ}$ and $90^{\circ}$, the maximum values of deviation for Head 1, Head 2 and Head 3 were 0.48%, 1.06% and 0.40%, respectively. The measurement agreement is within the range of results obtainable for conventional treatment machines. The low strength of the magnetic field does not affect dose measurements. Using the SWP to water correction factor, absolute doses for $ViewRay^{(R)}$ system can be measured.

• Investigative Magnetic Resonance Imaging
• /
• v.8 no.1
• /
• pp.1-8
• /
• 2004

Purpose : Information about electrical activity inside the brain during fMRl scans is very useful in monitoring physiological function of the patient or locating the spatial position of the activated region in the brain. However, many additional noises appear in the EEG signal acquired during the MRI scan. Gradient induced noise is the biggest one among the noises. In this work, we propose a gradient noise reduction method using the independent component analysis (ICA) method. Materials and Methods : We used a 29-channel MR-compatible EEG measurement system and a 3.0 Tesla MRI system. We measured EEG signals on a subject lying inside the magnet during EPI scans. We selectively removed the gradient noise from the measured EEG signal using the ICA method. We compared the results with the ones obtained with conventional averaging method and PCA method. Results : All the noise reduction methods including the averaging and PCA methods were effective in removing the noise in some extent. However, the proposed ICA method was found to be superior to the other methods. Conclusion : Gradient noise in EEG signals acquired during fMRI scans can be effectively reduced by the ICA method. The noise-reduced EEG signal can be used in fMRI studies of epileptic patients or combinatory studies of fMRI and EEG.

• Korean Journal of Clinical Laboratory Science
• /
• v.50 no.1
• /
• pp.1-10
• /
• 2018

During early pregnancy, before the development of a functioning thyroid gland, thyroid stimulating hormone (TSH) is a very sensitive marker of thyroid dysfunction during pregnancy. Normal values have been modified during gestation with a downward shift. The fetus is influenced by the TSH supplied by the mother. TSH and free thyroxine (FT4) concentrations vary during pregnancy and conventional units can vary between laboratories. A downward shift of the TSH reference range occurs during pregnancy, with a decrease in both the lower and upper limits of maternal TSH, relative to the typical non-pregnant TSH reference range. Each laboratory produces its own reference TSH and FT4 concentrations because there are many different assays that yield different results in pregnancy. Therefore, automated immunoassays used for serum FT4 analysis are still used widely, but the important considerations discussed above must be noted. The use of population-based, trimester-specific reference ranges remains the best way to handle this issue The slight downward shift in the upper reference range of TSH occurring in the latter first trimester (7~12 weeks) of pregnancy, typically not observed prior to 7 weeks. Their use indicates high or low levels in a quantitative manner independent of the reference ranges. These data highlight the importance of calculating population-based pregnancy-specific thyroid parameter reference intervals. A precision medicine initiative in this area will require the collection and analysis of a large number of genetic, biological, psychosocial, and environmental variables in large cohorts of individuals. Large prospective randomized controlled trials will be needed to resolve these controversies.

• Korean Journal of Head & Neck Oncology
• /
• v.16 no.2
• /
• pp.172-176
• /
• 2000

Objectives: To improve local control and reduce toxicity, 3-D conformal radiotherapy was used as a boost the primary tumor site following fractionated radiotherapy in patients with nasopharyngeal carcinoma. Materials and Methods: Eight patients with previously untreated nasopharyngeal carcinomas were treated with 3-D conformal radiotherapy following fractionated radiotherapy from September 1998 to April 2000. All patients had biopsy confirmation of disease before radiation therapy. Stages were II in 1, III in 5, and IV in 2. Two patients received cisplatin based chemotherapy in addition to radiation therapy; induction chemotherapy in 1, concurrent chemoradiation in 1. 3-D conformal radiotherapy delivered using 6MV Linac as a boost(range 25.2-28.8Gy, median 25.7Gy) following conventionally fractionated radiotherapy(range 50.4Gy). Average total dose ranged from 75.6-79.2Gy(median 76Gy). Follow-up time was 4-21 months(median 9.6 months). Results: Seven of 8 patients were evaluated radiologically within 3 months after completion of radiation therapy. All 7 patients were seen complete remission. One of 7 patients had distant metastasis after 5 months and local failure after 7 months. The tree interval of local recurrence was ranged from 4 - 21 months(median 10.2 months). One patient without radiological evaluation got complete remission clinically. Treatment related toxicity was grade 1-3 xerostomia, dysphagia, and mucositis. During 3-D conformal radiotherapy, there was no aggravation of any toxicity. Conclusion: Although the number of patients was small and follow-up period was short, 3-D conformal radiotherapy following conventional radiotherapy improved tumor control and dose escalation without increased toxicity. Survival and late toxicity should be evaluated through long term follow-up. In addition, it is necessary to confirm the benefits of 3-D conformal radiotherapy in nasopharyngeal carcinoma with randomized trial.

• Asian-Australasian Journal of Animal Sciences
• /
• v.12 no.8
• /
• pp.1251-1257
• /
• 1999

Two experiments were conducted to determine the effects of roasting and extrusion on nutritional value of conventional and low-inhibitor soy beans for nurser-age pigs. In Exp. 1, 100 weaning pigs (7.5 kg average initial BW) were used in a 35-d growth assay to determine the effects of processing method (roasting in a Rast-A-Tron$^{TM}$ raster vs extrusion in an Insta-Pro$^{TM}$ extruder) on the nutritional value of Williams 82 soybeans with (+K) and without (-K) gene expression for the Kunitz trypsin inhibitor. Treatments were 48% soybean meal with added soybean oil, +K roasted, +K extruded, -K roasted and -K extruded. All diets were formulated to contain 3.5 Mcal DE/kg, with 0.92% lysine for d 0 to 14 and 0.76% lysine for d 14 to 35 of the experiment. The lysine concentrations were 80% of NRC (1988) recommendations to accentuate difference in response to protein quality and lysine availability. For d 0 to 14, pigs fed extruded soybeans (+K and -K) had greater ADG (p<0.001), ADFI (p<0.09) and gain/feed (p<0.01) than pigs fed roasted soybeans. For d 14 to 35 and overall, the same effects were noted, i.e., pigs fed extruded soybeans had greater ADG, ADFI and gain/feed than pigs fed roasted soybeans (p<0.03). Also, pigs fed -K soybeans were more efficient (p<0.008) than pigs fed +K soybeans. In Exp. 2, 150 weanling pigs (7.0 kg average initial BW) were used in a 35-d growth assay. All diets were formulated to contain 3.5 Mcal DE/kg, with 1.25% lysine for d 0 to 14 and 1.10% lysine for d 14 to 35 of the experiment. The lysine concentrations were formulated to be in excess of NRC recommendation to determine if differences in nutritional value of the soybean preparations could be detected in protein-adequate diets. For d 0 to 14 (p<0.06), 14 to 35 (p<0.03) and 0 to 35 (p<0.02), pigs fed extruded soybeans had greater ADG and gain/feed than pigs fed roasted soybeans. Apparent digestibilities of DM, N and GE were greater for diets with extruded soybeans than diets with roasted soybeans and diets with soybean meal and soybean oil were intermediate. The response to extrusion processing was greater with -K than +K soybeans, with pigs fed extruded -K soybeans having the greatest growth performance and nutrient digestibilities and lowest skin-fold thickness of any treatment. In conclusion, extrusion yielded a full-fat soy product of greater nutritional value than roasting. Also, selection against genetic expression of the Kunitz trypsin inhibitor improved nutritional value of the resulting soybean preparations.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.6
• /
• pp.2961-2966
• /
• 2012

Extremely low frequency electro magnetic fields (EMFs) have been classified as possibly carcinogenic to humans by the International Agency for Research on Cancer. An increased number of chromosomal alterations in peripheral lymphocytes are correlated with elevated incidence of cancer. The aim of the present study was to assess occupationally induced chromosomal damage in EMF workers exposed to low levels of radiation. We used conventional metaphase chromosome aberration (CA) analysis and the micronucleus (MN) assay as biological indicators of non ionizing radiation exposure. In the present study totally 70 subjects were selected including 50 exposed and 20 controls. Informed written consent was obtained from all participants and the study was performed in accordance with the Declaration of Helsinki and the approval of the local ethical committee. A higher degree of CA and MN was observed in exposed subjects compared to controls, the frequency of CA being significantly enhanced with long years of exposure (P<0.05). Moreover increase in CA and MN with age was noted in both exposed subjects and controls, but was significantly greater in the former. The results of this study demonstrated that a significant induction of cytogenetic damage in peripheral lymphocytes of workers occupationally exposed to EMFs in electric transformer and distribution stations. In conclusion, our findings suggest that EMFs possess genotoxic capability, as measured by CA and MN assays; CA analysis appeared more sensitive than other cytogenetic end-points. It can be concluded that chronic occupational exposure to EMFs may lead to an increased risk of genetic damage among electrical workers.

• Journal of Pharmaceutical Investigation
• /
• v.32 no.4
• /
• pp.267-275
• /
• 2002

A self-microemulsifying drug delivery system (SMEDDS) was developed to increase the dissolution rate, solubility, and ultimately bioavailability of a poorly water soluble drug, lovastatin. SMEDDS was thε mixtures of oils, surfactants, and cosurfactants, which emulsify under conditions of gentle agitation, similar to those which would be encountered in the gastro-intestinal (GI) tract. Various types of self-emulsifying formulations were prepared using four types of oil (Capryol 90, Lauroglycol 90, Labrafil M 1944 CS and Labrafil M 2125), two surfactants (Cremophor EL and Tween 80), and three cosurfactants (Carbitol, PEG 400 and propylene glycol). Thε efficiency of emulsification was studied using a laser diffraction size analyzer to determine particle size distributions of the resultant emulsions. Optimized formulations selected for bioavailability assessment were Carpryol 90 (40%), Cremophor EL (30%) and Carbitol (30%). SMEDDS containing lovastatin (20 mg and 5 mg) were compared to a conventional lovastatin tablet $(Mevacor^{\circledR},\;20\;mg/tab)$ by the oral administration as prefilled hard gelatin capsules to fasted beagle dogs for in vivo study. The arεa under the serum concentration-time curve from time zero to the last measured time in serum, $AUC_{0{\rightarrow}24h}$, was significantly greater in SMEDDS, suggesting that bioavailability increase 130% and 192% by the SMEDDS, respectively. The self-emulsifying formulations of lovastatin afforded the improvement in absolute oral bioavailability relative to previous data of lovastatin tablet formulation. These data indicate the utility of dispersed self-emulsifying formulations for the oral delivery of lovastatin and potentially other poorly absorbed drugs.

• Journal of Pharmaceutical Investigation
• /
• v.39 no.6
• /
• pp.401-409
• /
• 2009

Ketrorolac tromethamine (KT), a nonsteroidal anti-inflammatory drug (NSAID) is required repeated administration due to its short blood half-life. To avoid dose-dependent side effects of KT, sustained-release pellets containing KT were prepared by coating with Eudragit$^{(R)}$ RS 100 and Eudragit$^{(R)}$ NE 30D. The in vitro and in vivo drug release behavior of KT from Eudragit$^{(R)}$ RS 100 and NE 30D coated pellet (SR-A), Eudragit$^{(R)}$ RS 100 coated pellet (SR-B) and conventional commercial immediate-release tablet (IR) was investigated. KT from SR-A and SR-B was slowly released over several hours, whereas IR showed rapid initial release in vitro. The pharmacokinetic study in vivo was performed by oral administration in beagle dogs. 5 mg IR was administered 3 times at intervals 5 hr. Five milligrams of IR was administered 3 times at intervals of 5 hr and 15 mg of SR-A and SR-B did once. After administering IR, KT concentration in blood showed high peak- trough fluctuation and stomach ulcer were discovered. On the other hand, SR-A and SR-B sustainedly released KT and reduced the occurrence of stomach ulcer. There sustained-release pellets will be effective system to minimize dosedependent of side effect and improve patient compliance.