• Title/Summary/Keyword: laboratory measurement methods

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A Study on the Skin Irritation Toxicity Test of Processed Sulfur in New Zealand White Rabbit

  • Jung, Hoseok;Seo, Wookcheol;Jeong, Taeseong;Kang, Hyung Won;Kim, Sungchul
    • Journal of Pharmacopuncture
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    • v.25 no.1
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    • pp.46-51
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    • 2022
  • Objectives: This study was performed to evaluate the skin irritation toxicity of processed sulfur. Methods: All experiments were conducted at Medvill (Korea), an institution authorized to perform non-clinical studies, under the Good Laboratory Practice (GLP) regulations. In order to investigate skin irritation toxicity of processed sulfur, we divided the back of six rabbits into two control sites and two test sites. One of each of the two control and test sites was then designated abraded sites and intact sites. In test sites, 0.5 g of processed sulfur was applied to the back of the rabbit for 24 hours, and in control sites, 0.5 g of sterile distilled water was applied in the same way. We observed and evaluated mortality, weight, general symptoms, and skin irritation toxicity. This study was conducted with the approval of the Animal Ethics Committee (Approval number: IAC2020-1549). Results: In all experiments, no dead animals were observed. In all cases, skin coloration was observed at 24 hours after processed sulfur administration. This coloration lasted up to 48 hours and is believed to be the effect of the administration of test substances. Weight measurement indicated that weight was lost 72 hours after administration in three cases, but this is considered an accidental weight change. Normal weight gain was observed in the remaining subjects. In all animals, no skin irritation toxicity was observed, and the primary irritation index (P.I.I) was calculated as 0.0 according to Draize's evaluation method. Conclusion: The above findings suggest that it is relatively safe to apply a processed sulfur to the skin. Further research on this topic is needed to provide more specific evidence.

Antibacterial Activities of Eighteen Types of Essential Oils on S. mutans, P. gingvalis, and L. gasseri (에센셜 오일 18종의 S. mutans, P. gingivalis, L. gasseri에 대한 항균능 분석)

  • Yoon, Hyun-Seo;Park, Chung-Mu
    • Journal of The Korean Society of Integrative Medicine
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    • v.10 no.4
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    • pp.103-111
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    • 2022
  • Purpose : In recent years, essential oils have been produced using natural extracts for various uses. Their functionality is currently being tested not only for cosmetics and perfumes but also for other categories of products. Therefore, this study verified their antibacterial effects on S. mutans, P. gingivalis, and L. gasseri which are the representative strains that cause oral diseases. Methods : Eighteen types of natural essential oils were made at a concentration of 50 % (v/v) using Tween 20, and their antibacterial effects were verified by applying S. mutans, P. gingivalis, and L. gasseri. The antibacterial effects were measured with the disc diffusion method. All the experiments were repeated three times, and the mean value of three measurement values for each variable was used for data analysis. A one-way analysis of variance was conducted using these mean values. Results : Of the eighteen types of essential oils tested, sixteen types showed antibacterial effects on S. mutans, and sixteen and fifteen types exhibited antibacterial effects on P. gingivalis and L. gasseri respectively. The types of essential oils with high-level antibacterial activities were geranium, may chang, and bergamot for S. mutans, lemongrass, bergamot, and eucalyptus for P. gingivalis, and lemongrass, machan, and geranium for L. gasseri in order of antibacterial effect. This result was statistically significant (p<.001). In addition, in the case of mandarin oil, it was found that there was no antibacterial activity in all three strains. Conclusion : This study proved the antibacterial activities of essential oils, which are used for various purposes in daily life, against dental caries and periodontal diseases. The study results will likely be applied to different prevention programs for oral health and broadly used to develop products such as oral care items and dentifrices.

Effect of suprascapular nerve injury on muscle and regenerated enthesis in a rat rotator cuff tear model

  • Kenichiro Eshima;Hiroki Ohzono;Masafumi Gotoh;Hisao Shimokobe;Koji Tanaka;Hidehiro Nakamura;Tomonoshin Kanazawa;Takahiro Okawa;Naoto Shiba
    • Clinics in Shoulder and Elbow
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    • v.26 no.2
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    • pp.131-139
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    • 2023
  • Background: Massive rotator cuff tears (RCTs) are complicated by muscle atrophy, fibrosis, and intramuscular fatty degeneration, which are associated with postoperative tendon-to-bone healing failure and poor clinical outcomes. We evaluated muscle and enthesis changes in large tears with or without suprascapular nerve (SN) injury in a rat model. Methods: Sixty-two adult Sprague-Dawley rats were divided into SN injury (+) and SN injury (-) groups (n=31 each), comprising tendon (supraspinatus [SSP]/infraspinatus [ISP]) and nerve resection and tendon resection only cases, respectively. Muscle weight measurement, histological evaluation, and biomechanical testing were performed 4, 8, and 12 weeks postoperatively. Ultrastructural analysis with block face imaging was performed 8 weeks postoperatively. Results: SSP/ISP muscles in the SN injury (+) group appeared atrophic, with increased fatty tissue and decreased muscle weight, compared to those in the control and SN injury (-) groups. Immunoreactivity was only positive in the SN injury (+) group. Myofibril arrangement irregularity and mitochondrial swelling severity, along with number of fatty cells, were higher in the SN injury (+) group than in the SN injury (-) group. The bone-tendon junction enthesis was firm in the SN injury (-) group; this was atrophic and thinner in the SN injury (+) group, with decreased cell density and immature fibrocartilage. Mechanically, the tendon-bone insertion was significantly weaker in the SN injury (+) group than in the control and SN injury (+) groups. Conclusions: In clinical settings, SN injury may cause severe fatty changes and inhibition of postoperative tendon healing in large RCTs. Level of evidence: Level Basic research, controlled laboratory study.

The Effect of Breathing Technique with Aerobic Exercise on the Respiratory Function of Adults (유산소 운동 시 호흡 기법에 따라 호흡 기능에 미치는 영향)

  • Ji-Won Han;Keon-Cheol Lee;In-Seob Kim
    • Journal of The Korean Society of Integrative Medicine
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    • v.11 no.4
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    • pp.135-145
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    • 2023
  • Purpose : The purpose of this study was to discover which breathing technique is more effective in improving respiratory function by applying different breathing techniques-the chest expansion respiratory technique and the abdominal expansion respiratory technique-to adults in the same aerobic exercise situation. Methods : In this study, 30 people were randomly assigned to two groups: chest expansion respiratory technique with aerobic exercise (A group) and abdominal expansion respiratory technique with aerobic exercise (B group). Group A was asked to breathe after wrapping their rib cage with an elastic band, and Group B was asked to breathe after wrapping their abdomen with an elastic band. A total of 3 sets of 30 breaths were performed, 3 times a week for 6 weeks. For statistical processing, an independent t-test was used to verify homogeneity between the two groups, and a repeated measure analysis of variance (ANOVA) was used to compare differences according to the period for each group. Results : The changes in FVC and FEV1 for each group following 6 weeks of intervention are as follows. In comparison according to the intervention period, there was a significant increase in all groups depending on the timing of measurement (p<.05), and as a result of the inter-subject effect test, there was no significant difference between groups (p>.05). In addition, there was no interaction effect between period and group (p>.05). Conclusion : The conclusion of this study is that FVC and FEV1 values increased according to the intervention period in both groups; therefore, it can be suggested that flexible breathing techniques can be applied depending on the patient's physical situation when applying a breathing program to improve respiratory function.

A Fiber Spool's Vibration Sensitivity Optimization Based on Orthogonal Experimental Design

  • Jing Gao;Linbo Zhang;Dongdong Jiao;Guanjun Xu;Xue Deng;Qi Zang;Honglei Yang;Ruifang Dong;Tao Liu;Shougang Zhang
    • Current Optics and Photonics
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    • v.8 no.1
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    • pp.45-55
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    • 2024
  • A fiber spool with ultra-low vibration sensitivity has been demonstrated for the ultra-narrow-linewidth fiber-stabilized laser by the multi-object orthogonal experimental design method, which can achieve the optimization object and analysis of influence levels without extensive computation. According to a test of 4 levels and 4 factors, an L16 (44) orthogonal table is established to design orthogonal experiments. The vibration sensitivities along the axial and radial directions and the normalized sums of the vibration sensitivities are determined as single objects and comprehensive objects, respectively. We adopt the range analysis of object values to obtain the influence levels of the four design parameters on the single objects and the comprehensive object. The optimal parameter combinations are determined by both methods of comprehensive balance and evaluation. Based on the corresponding fractional frequency stability of ultra-narrow-linewidth fiber-stabilized lasers, we obtain the final optimal parameter combination A3B1C2D1, which can achieve the fiber spool with vibration sensitivities of 10-12/g magnitude. This work is the first time to use an orthogonal experimental design method to optimize the vibration sensitivities of fiber spools, providing an approach to design the fiber spool with ultra-low vibration sensitivity.

A comparative analysis of canine pancreatic lipase tests for diagnosing pancreatitis in dogs

  • Jin-Kyung Kim;Sun Young Hwang;Se Eun Kim;Gahyun Lee;Soungjin Ji;Jungho Kim;Yongbaek Kim
    • Journal of Veterinary Science
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    • v.25 no.3
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    • pp.48.1-48.12
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    • 2024
  • Importance: Early diagnosis of canine pancreatitis is challenging due to non-specific clinical signs. Currently, abdominal ultrasonography and measurement of canine pancreatic lipase (cPL) have been employed for the diagnosis of pancreatitis. Objective: Many qualitative and quantitative commercial cPL tests have been developed and used in veterinary clinics. This study aimed to compare three different methodologies SNAP cPL, Spec cPL, and Vcheck cPL tests to assess the concordance of these assays. Methods: Fifty serum samples were collected from 36 dogs with or without pancreatitis and subjected to SNAP cPL, Spec cPL, and Vcheck cPL tests. Agreement and correlation coefficients were calculated between the test results, and correlations were determined during the management of the patients. Results: The results of the three cPL assays were strongly correlated in 47/50 serum samples (94%). Cohen's kappa analysis between the Spec cPL and Vcheck cPL showed near perfect agreement (κ = 0.960, p < 0.001), SNAP cPL and Vcheck cPL (κ = 0.920, p < 0.001), and Spec cPL and SNAP cPL (κ = 0.880, p < 0.001). The correlation coefficients (r) between data from Spec cPL and Vcheck cPL tests was calculated by Spearman's correlation test (r = 0.958, p < 0.001). Furthermore, the patterns of change in serum cPL concentrations determined using Spec cPL and Vcheck cPL were significantly consistent during the monitoring period in 11 patients. Conclusions and Relevance: Our data illustrated that Spec cPL and Vcheck cPL tests are compatible for clinical use in the diagnosis and monitoring of canine pancreatitis.

The Use of MTT Assay, In Vitro and Ex Vivo, to Predict the Radiosensitivity of Colorectal Cancer (In-vitro와 Ex-vivo MTT Assay를 통한 직장암의 방사선치료 감수성 예측 가능성 검증)

  • Kim, Ji-Eun;Kim, Mi-Sook;Kang, Chang-Mo;Kim, Jong-Il;Shin, Hye-Kyung;Choi, Chul-Won;Seo, Young-Seok;Ji, Young-Hoon
    • Radiation Oncology Journal
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    • v.26 no.3
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    • pp.166-172
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    • 2008
  • Purpose: The measurement of radiosensitivity of individuals is useful in radiation therapy. Unfortunately, the measurement of radiation survival using a clonogenic assay, which is the established standard, can be difficult and time consuming. The aim of this study is to compare radiosensitivity results obtained from the MTT and clonogenic assays, and to evaluate whether the MTT assay can be used on clinical specimens. Materials and Methods: HCT-8, LoVo, CT-26, and WiDr were the colon cancer cell lines used for this study. The clonogenic assay was performed to obtain the cell survival curves and surviving fractions at a dose of 2 Gy ($SF_2$) as the standard technique for radiosensitivity. Also, the MTT assay was performed for each of the cell lines (in vitro). To simulate clinical specimens, the cell lines were inoculated into nude mice, removed when the tumors reached 1 cm in diameter, and chopped. Next, the tumors were subjected to the same process involved with the MTT assay in vitro. The inhibition rates (IR) of 10 Gy or 20 Gy of irradiation for in vitro and ex vivo were calculated based on the optical density of the MTT assay, respectively. Results: According to $SF_2$ and the cell survival curve, the HCT-8 and WiDr cell lines were more resistant to radiation than LoVo and CT-26 (p<0.05). The IR was measured by in vitro. The MTT assay IR was 17.3%, 21%, 30% and 56.5% for the WiDr, HCT-8, LoVo and CT-26 cell lines, respectively. In addition, the IR measured ex vivo by the MTT assay was 23.5%, 26%, 38% and 53% in the HCT-8, WiDr, LoVo and CT-26 tumors, respectively. Conclusion: The radiosensitivity measured by the MTT assay was correlated with the measures obtained from the clonogenic assay. This result highlights the possibility that the MTT assay could be used in clinical specimens for individual radiosensitivity assays.

Development of soil certified reference material for determination of the hazardous elements (유해원소 측정용 토양 인증표준물질 개발)

  • Kim, In-Jung;Min, Hyung-Sik;Suh, Jung-Ki;Han, Myung-Sub;Lim, Myung-Chul;Kim, Young-Hee;Shin, Sun-Kyoung;Cho, Kyung-Haeng
    • Analytical Science and Technology
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    • v.23 no.5
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    • pp.485-491
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    • 2010
  • A certified reference material (CRM) of KRISS 109-03-SSD was developed for the analysis of hazardous elements in soil. The target elements were As, Cd, Cr, Cu, Hg, Ni, Pb, Zn being regulated by the Soil Environment Conservation Act. Starting material was collected from tailing dump of an unworked tungsten mine at Sangdong (Gangwon-do, Korea). The starting material under-went through a series of fabricating process steps of screening, drying, grinding, sieving, blending, bottling, sterilization and was certified according to the ISO Guide 35. Isotope dilution-inductively coupled mass spectrometry (ID-ICP/MS) and instrumental neutron activation analysis (INAA) were used for the measurement. Homogeneity was tested according to ISO 13528 annex B. The certified values were determined using the results from two different methods or from two independent measurements using a method. Finally, certified values of seven elements of arsenic, cadmium, chromium, copper, lead, nickel and zinc were determined. Mercury did not satisfied the criteria of homogeneity and the result would be provided for information only, together with iron and tungsten. It was also studied, the extractable fraction of elements by aqua regia according to the ISO 11466 protocol being frequently studied for the purpose of environmental monitoring. It was performed as a inter-laboratory study by 6 laboratories of a public institute and universities. Standard deviation among the laboratories was much bigger than the uncertainty of the certified value. The result of inter-laboratory study on the extractable fraction will be provided for information, only.

Comparison of micro CT and cross-section technique for evaluation of marginal and internal fit of lithium disilicate crowns (전부 도재관의 변연 및 내면 간극에 대한 micro CT와 절단 시편 측정법의 비교)

  • Ko, In-Seok;Kim, Jeong-Mi;Cho, Hye-Won
    • The Journal of Korean Academy of Prosthodontics
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    • v.54 no.3
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    • pp.226-233
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    • 2016
  • Purpose: The purpose of this study was to evaluate the adaptation of lithium disilicate crowns fabricated by CAD-CAM (computer aided design-computer aided manufacturing) and heat-press technique to compare two different measurement methods in assessing fit of the ceramic crowns: micro CT and cross-section technique. Materials and methods: A prepared typodont mandibular molar for ceramic crown was duplicated and ten dies were produced by milling the PMMA (polymethylmethacrylate) resin. Ten vinyl polysiloxane impressions were made and stone casts were produced. Five dies were used for IPS e.max Press crowns with heat-press technique. The other five dies were used for IPS e.max CAD crowns with CAD-CAM technique. Ten lithium disilicate crowns were cemented on the resin dies using zinc phosphate cement with finger pressure. The marginal and internal fits in central buccolingual plane were evaluated using a micro CT. Then the specimens were embedded and cross-sectioned and the marginal and internal fits were measured using scanning electronic microscope. The two measurement methods and two manufacturing methods were compared using Mann-Whitney U test (SPSS 22.0). Results: The marginal and internal fit values using micro CT and cross-section technique were similar, showing no significant differences. There were no significant differences in adaptation between lithium disilicate crowns fabricated with CAD-CAM and heat-press technique. Conclusion: Both micro CT and cross-section technique were acceptable methods in the evaluation of marginal and internal fit of lithium disilicate crown. There was no difference in adaptation between lithium disilicate crowns fabricated with CAD-CAM and heat-press technique except occlusal fit.

ESTIMATION OF CLEAR WOOD PROPERTIES BY NEAR INFRARED SPECTROSCOPY

  • Schimleck, Laurence R.;Evans, Robert;Ilic, Jugo;Matheson, A.Colin
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1161-1161
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    • 2001
  • Rapid cost-effective methods of measuring wood quality are extremely important to tree improvement programs where it is necessary to test large numbers of trees. Non-destructive sampling of a forest can be achieved by using increment cores generally removed at breast height. At CSIRO Forestry and Forest Products methods for the rapid, non-destructive measurement of wood properties and wood chemistry based on increment core samples have been developed. In this paper the application of near infrared (NIR) spectroscopy to the prediction of a range solid wood properties, including density, longitudinal modulus of elasticity (E$\sub$L/) and microfibril angle (MFA), is described. Experiments conducted on individual species (Eucalyptus delegatensis and Pinus radiata), the two species combined and a number of mixed species from several genera are reported. NIR spectra were obtained from the radial/longitudinal face of each sample and used to develop calibrations for the measured physical properties. When the individual species were used the relationships between laboratory determined data and NIR fitted data were good in all cases. Coefficients of determination (R$^2$) ranging from 0.77 for MFA to 0.93 for stick density were obtained for E. delegatensis and R$^2$ ranging from 0.68 for MFA to 0.94 for strip density were obtained for P. radiata. The calibration statistics for the combined E. delegatensis and P. radiata samples were similar to those found for the individual species. As these results indicated that it might be possible to produce general calibrations based on samples from a number of species of a single genus or samples from a number of different genera, a wide range of species was subsequently tested. Good relationships were obtained for both density and E$\sub$L/. These calibrations had R$^2$ that were slightly lower than those determined using individual species and standard errors that were higher. The mixed species calibrations, when applied to the E. delegatensis and P. radiata sample sets, provided good estimates of density (stick and strip) and E$\sub$L/. The results demonstrated that a mixed species calibration, that encompasses wide variation in terms of, wood anatomy, chemistry and physical properties, could be used to rank trees. Experiments reported in this paper demonstrate that solid wood properties can be estimated by NIR spectroscopy. The method offers a rapid and non-destructive alternative to traditional methods of analysis and is applicable to large-scale non-destructive forest resource assessment, and to tree breeding and silvicultural programs.

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