• The korean journal of orthodontics
• /
• v.36 no.6
• /
• pp.422-433
• /
• 2006

Objective: Several ions and components are released from self-etching primers in the oral cavity. This may cause injury to the periodontal tissues throughout orthodontic treatment. The purpose of this study was to assess the cytotoxicity of self-etching primers to HGF-1, HaCaT, and RHEK cells. Method: Transbond XT Primer (3M Unitek, Monrovia, CA, USA), and self-etching primers, Clearfil SE Bond (Kuraray, Osaka, Japan), Transbond Plus SEP (3M Unitek, Monrovia, CA, USA), and Adper Prompt L-Pop (3M Unitek, Monrovia, CA, USA), were evaluated by MTT assay, and cellular changes were also observed. Results: In all cells after 72 hours with all primers, severe morphological changes such as atrophy and necrosis were observed. In the MTT assay using HGF-1, Clearfil SE Bond, Transbond XT Primer, Transbond Plus SEP, and Adper Prompt L-Pop were lined up in order of ascending cytotoxicity When using HaCaT, Clearfil SE Bond, Adper Prompt L-Pop, Transbond Plus SEP, and Transbond XT Primer were lined up in order of ascending cytotoxicity. When using RHEK, Clearfil SE Bond, Transbond XT Primer, Adper Prompt L-Pop, and Transbond Plus SEP were lined up in order of ascending cytotoxicity. Conclusion: The result of this study shows that care is needed because self-etching primers show cytotoxic properties similar to conventional primers.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.25 no.5
• /
• pp.855-864
• /
• 1996

The purpose of this study is to evaluate nutritional status of tube feeding patients, and to investigate the effects of giving enteral nutritional support to them. 83 in-patients have been examined for their nutritional status. The mean caloric density was 0.77kca1/m1. 36.1% to 75.9% of them were malnourished in terms of biochemical assessment. The energy intake showed the significant and positive correlation in all biochemical parameters. And the protein intake showed the significant and positive correlation in total protein, serum albumin, serum iron, hemoglobin, hematocrit and TLC. But age was correlated negatively to serum albumin and transferrin. The amount of energy and protein intake has been significantly increased as the tube feeding duration became longer. Also the effect of enteral nutritional support for 6 weeks has been investigated. Case group(n=8) was administered 250kca1 of polymeric formula in addition to their usual diet, while control group(n=8) kept the amount of their original intake. When comparing the biochemical changes of the case group and those of control group at week 0 and week 6 respectively, it showed significant differences in total protein, serum transferrin and TLC. This study suggests that the malnourished status of tube feeding patients can be improved and even prevented if nutritional support is properly administered.

• Restorative Dentistry and Endodontics
• /
• v.35 no.2
• /
• pp.80-87
• /
• 2010

The purpose of this study was to compare the different canal irrigation methods to prevent the formation of precipitate between sodium hypochlorite (NaOCl) and chlorhexidine (CHX). Extracted 50 human single-rooted teeth were used. The root canals were instrumented using NiTi rotary file (Profile .04/#40) with 2.5% NaOCl and 17% EDTA as irrigants. Teeth were randomly divided into four experimental groups and one control group as follows; Control group: 2.5% NaOCl only, Group 1: 2.5% NaOCl + 2% CHX, Group 2: 2.5% NaOCl + paper points + 2% CHX, Group 3: 2.5% NaOCl + preparation with one large sized-file + 2% CHX, Group 4: 2.5% NaOCl +95% alcohol+ 2% CHX. The teeth were split in bucco-lingual aspect and the specimens were observed using Field Emission Scanning Electron Microscope. The percentages of remaining debris and patent dentinal tubules were determined. Statistical analysis was performed with one-way analysis of variance (ANOVA). Energy Dispersive x-ray Spectroscopy was used for analyzing the occluded materials in dentinal tubule for elementary analysis. There were no significant differences in percentage of remaining debris and patent tubules between all experimental groups at all levels (p > .05). In elementary analysis, the most occluded materials in dentinal tubule were dentin debris. NaOCl/CHX precipitate was detected in one tooth specimen of Group 1. In conclusion, there were no significant precipitate on root canal, but suspected material was detected on Group 1. The irrigation system used in this study could be prevent the precipitate formation.

• Korean Journal of Dental Materials
• /
• v.45 no.4
• /
• pp.257-274
• /
• 2018

The purpose of this study was to evaluate the effect of acid-treatment conditions on the surface properties of the RBM (Resorbable Blast Media) treated titanium. Disk typed cp-titanium specimens were prepared and RBM treatments was performed with calcium phosphate ceramic powder. Acid solution was mixed using HCl, $H_2SO_4$ and deionized water with 4 different volume fraction. The RBM treated titanium was acid treated with different acid solutions at 3 different temperatures and for 3 different periods. After acid-treatments, samples were cleaned with 1 % Solujet solution for 30 min and deionized water for 30 min using ultrasonic cleanser, then dried in the electrical oven ($37^{\circ}C$). Weight of samples before and after acid-treatment were measured using electric balance. Surface roughness was estimated using a confocal laser scanning microscopy, crystal phase in the surface of sample was analyzed using X-ray diffractometer. Surface morphology and components were evaluated using Scanning Electron Microscope (SEM) with Energy Dispersive X-ray spectroscopy (EDX) and X-ray Photoemission Spectroscopy (XPS). Values of the weight changes and surface roughness were statistically analyzed using Tukey-multiple comparison test (p=0.05). Weight change after acid treatments were significantly increased with increasing the concentration of $H_2SO_4$ and temperature of acid-solution. Acid-treatment conditions (concentration of $H_2SO_4$, temperature and time) did not produce consistent effects on the surface roughness, it showed the scattered results. From XRD analysis, formation of titanium hydrides in the titanium surface were observed in all specimens treated with acid-solutions. From XPS analysis, thin titanium oxide layer in the acid-treated specimens could be evaluated. Acid solution with $90^{\circ}C$ showed the strong effect on the titanium surface, it should be treated with caution to avoid the over-etching process.

• Korean Journal of Mineralogy and Petrology
• /
• v.34 no.2
• /
• pp.133-146
• /
• 2021

Aragonite is one of common polymorphs of calcium carbonate (CaCO₃) and formed via biological or physical processes through precipitation in many different environments including marine ecosystems. It is noted that aragonite formation and growth as well as the substitution of trace elements such as strontium (Sr) in the aragonite structure would be dependant on several key parameters such as concentrations of chemical species and temperature. In this study, properties of the incorporation of Sr into aragonite were investigated over a wide range of various saturation conditions and temperatures similar to the marine ecosystem. All pure aragonite samples were inorganically synthesized through a constant-addition method with varying concentrations of the reactive species ([Ca]=[CO₃] 0.01-1 M), injection rates of the reaction solution (0.085-17 mL/min), and solution temperatures (5-40 ℃). Pure aragonite was also formed even under the Sr incorporation conditions (0.02-0.5 M, 15-40 ℃). When temperature and saturation index (SI) with respect to aragonite increased, the crystallinity and the crystal size of aragonite increased indicating the growth of aragonite crystal. However, it was difficult to interpret the crystal growth rate because the crystal growth rate calculated using BET-specific surface area was significantly influenced by the crystal morphology. The distribution coefficient of Sr (K_Sr) into aragonite decreased from 2.37 to 1.57 with increasing concentrations of species (Ca²⁺ and CO₃^2-) at a range of 0.02-0.5 M. Similarly, it was also found that K_Sr decreased 1.90 to 1.54 at a range of 15-40 ℃. All K_Sr values are greater than 1, and the inverse correlation between the K_Sr and the crystal growth rate indicate that Sr incorporation into aragonite is in a compatible relationship.

• Korean journal of psychology:General
• /
• v.36 no.1
• /
• pp.81-107
• /
• 2017

The study aims to investigate the clinical utility of Bayley-III using US norm in Korea. A total of 98 preterm infants and 93 term infants were assessed with the K-Bayley-III. The performance pattern of preterm infants was analyzed with mixed design ANOVA which examined the differences of scaled scores and composite scores of Bayley-III between full term- and preterm- infant group and within preterm infants group. Then, We have investigated agreement between classifications of delay made using the BSID-II and Bayley-III. In addition, ROC plots were constructed to identify a Bayley-III cut-off score with optimum diagnostic utility in this sample. The results were as follows. (1) Preterm infants have significantly lower function levels in areas of 5 scaled scores and 3 developmental indexes compared with infants born at term. Significant differences among scores within preterm infant group were also found. (2) Bayley-III had the higher scores of the Mental Development Index and Psychomotor Developmental Index comparing to the scores of K-BSID-II, and had the lower rates of developmental delay. (3) All scales of Bayley-III, Cognitive, Language and Motor scale had the appropriate level of discrimination, but the cut-off composite scores of Bayley-III were adjusted 13~28 points higher than 69 for prediction of delay, as defined by the K-BSID-II. It explains the lower rates of developmental delay using the standard of two standard deviation. This study has provided empirical data to inform that we must careful when interpreting the score for clinical applications, identified the discriminating power, and proposed more appropriate cut-off scores. In addition, discussion about the sampling for making the Korean norm of Bayley-III was provided. It is preferable that infants in Korea should use our own validated norms. The standardization process to get Korean normative data must be performed carefully.

• Korean Journal of Psychosomatic Medicine
• /
• v.31 no.2
• /
• pp.63-71
• /
• 2023

Urinary incontinence (UI), affecting 3%-11% of males and 25%-45% of females globally, is expected to rise with an aging population. It significantly impacts mental health, causing depression, stress, and reduced quality of life. UI can exacerbate psychiatric conditions, affecting treatment compliance and effectiveness. It is categorized into transient and chronic types. Transient UI, often reversible, is caused by factors summarized in the acronym DIAPPERS: Delirium, Infection, Atrophic urethritis/vaginitis, Psychological disorders, Pharmaceuticals, Excess urine output, Restricted mobility, Stool impaction. Chronic UI includes stress, urge, mixed, overflow, functional, and persistent incontinence. Drug-induced UI, a transient form, is frequently seen in psychiatric treatment. Antipsychotics, antidepressants, and other psychiatric medications can cause UI through various mechanisms like affecting bladder muscle tone, altering nerve reflexes, and inducing other conditions like diabetes or epilepsy. Specific drugs like lithium and valproic acid have also been linked to UI, though mechanisms are not always clear. Managing UI in psychiatric patients requires careful monitoring of urinary symptoms and judicious medication management. If a drug is identified as the cause, options include discontinuing, reducing, or adjusting the dosage. In cases where medication continuation is necessary, additional treatments like desmopressin, oxybutynin, trihexyphenidyl, or amitriptyline may be considered.

• Korean Journal of Agricultural Science
• /
• v.12 no.2
• /
• pp.356-369
• /
• 1985

In Korea, inevitable researches for the blast control exactly started from 1927 by the organization of Office of Rural Development with the local extensive outbreak of panicle blast at Jeonlla Buk-Do Province in 1926. At present, the rice blast is still one of the most destructive and widespread diseases in spite of considerable contributions by rice scientists, particularly plant pathologists during last 55 years in Korea. Rice blast control and management are very difficult because of the marked variability in pathogenicity of the blast fungus. From the results obtained through the disease surveys during last 70 years, different 3 prevalence type of blast such as bimodal leaf-blast type, bimodal panicle-blast type and bimodal continual blast type were recognized. In generally speaking, pattern of blast outbreak is said to be characterized by severe outbreak of panicle blast after slight outbreak of leaf blast with discontinuity between leaf and panicle blast. So we have to pay much attention for successful management of panicle blast giving direct influence to rice yield. Main factors induce blast epidemic were pointed out to be breakdown of the disease resistance, nutritional unbalance such as excess application of nitrogen, delay of transplantation and longspell of rain fall by extensive surveys and researches on blast during last 70 years in Korea. The fact some of Japonica varieties such as Kokuryomiyako, Tamanishiki, Ginbozu and Pungok belong to varietal group A had been cultivated with extensive acrage over 30 years in this country should be mentioned by Korean rice scientists. Differences in field resistance between varieties in the same group are detectable and apparently small but sometimes epidemiologically significant differential effects may be found out in case of blast. Much more attention should be payed to accumulate the knowledges on field resistance for successful management of blast. Excess application of nitrogen is more effective to outbreak of panicle blast than that of leaf blast of IR varieties. In comparatively low level application of nitrogen infection rate of panicle blast of IR varieties is considerably high. Low temperature effects on outbreak of blast is very great. It results in remarkable increase of the inoculum potential on the leaf lesions and infection of panicle blast in leaf sheathes of IR varieties during the booting stage. In economic point of view, it is concluded that 5 times sprays of effective fungicides including 3 times before and 2 times after heading is good enough to control blast. We have experienced no one of control measures for blast is superior to all others. The integrated control measures was established as guideline of blast control around 1950 in Korea. This guideline must be helpful for rice growers as long as rice growing continue.