• The Journal of Advanced Prosthodontics
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• v.6 no.3
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• pp.165-170
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• 2014

PURPOSE. This study was aimed to evaluate effect of the desensitizing pretreatments on the micro-tensile bond strengths (${\mu}TBS$) to eroded dentin and sound dentin. MATERIALS AND METHODS. Forty-two extracted molars were prepared to form a flat dentin surface, and then they were divided into two groups. Group I was stored in distilled water while group II was subjected to a pH cycling. Each group was then subdivided into three subgroups according to desensitizing pretreatment used: a) pretreatment with desensitizer (Gluma); b) pretreatment with $CO_2$ Laser (Ultra Dream Pluse); c) without any pretreatment. All prepared surfaces were bonded with Single Bond 2 and built up with resin composite (Filtek Z250). The micro-tensile bond test was performed. Fracture modes were evaluated by stereomicroscopy. Pretreated surfaces and bonded interfaces were characterized by scanning electron microscope (SEM). The data obtained was analyzed by two-way ANOVA (${\alpha}$=0.05). RESULTS. For both sound and eroded dentin, samples treated with desensitizer showed the greatest ${\mu}TBS$, followed by samples without any treatment. And samples treated with $CO_2$ laser showed the lowest ${\mu}TBS$. SEM study indicated that teeth with eroded dentin appeared prone to debonding, as demonstrated by existence of large gaps between adhesive layers and dentin. CONCLUSION. Pretreatment with Gluma increased the ${\mu}TBS$ of Single Bond 2 for eroded and sound teeth. $CO_2$ laser irradiation weakened bond performance for sound teeth but had no effect on eroded teeth.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.149-152
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• 2000

Cryopreservation of infective juveniles of entomopathogenic nematode, Steinernema carpocapsae Weiser, was conducted at $-190^{\circ}C$ liquid nitrogen and its, efficacy was analysed on nematode survival and pathogenicity with glycerol pretreatments and storage periods. Infective juveniles were pre-treated before being frozen by incubating the nematodes in 22% glycerol for each of 6, 12, and 24 h, followed by 70% methanol at $0^{\circ}C$ for 10 minutes. Just after glycerol and methanol incubations, subsamp1es of the nematodes were resuspended in 0.85% saline and maintained during 24h for viability determination. Different glycerol incubation periods significantly affected the nematode susceptibility to methanol infiltration. Six hour incubation in glycerol resulted in much less nematode survival than did 12 h or 24 h incubation. About 70% of the infective juveniles frozen at $-190^{\circ}C$ for 5 months, preincubat-ed in glycerol at least for 12h, were able to survive after being resuspended in 30°C saline. They did not also show any change in their pathogenicity during cryopreservation. These results suggest an improved technique for long-term storage of the entomopathogenic nematodes.

• Journal of the Korean Chemical Society
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• v.38 no.6
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• pp.411-417
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• 1994

For the analysis of fine ceramics, which is one of the new materials difficult to be dissolved, the methods of sample pretreatments such as alkali fusion and high pressure acid digestion were studied using inductively coupled plasma-atomic emission spectrometer(ICP-AES). For the Al2O3 powder sample, the results from high pressure acid digestion method showed better reproducibility than those obtained by alkali fusion technique. In the case of the analysis of SiC powder using the former method, impurities of the powder in the range of ppm were determined without matrix interference by removing Si as Si-F volatilization. Japan Certified Reference Materials (JCRM022 and JCRM023) were analyzed by this method for ultra fine powder and the results showed high accuracy and good reproducibility.

• Journal of Veterinary Clinics
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• v.26 no.6
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• pp.534-538
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• 2009

Antiemetic effect of dexamethasone in dogs sedated with medetomidine was evaluated. On the day of experiment, five minutes prior to medetomidine ($40\;{\mu}g$/kg, IM) injection, dexamethasone was administered intravenously at the doses of 0.25, 0.5 and 1.0 mg/kg. Control group was received at 0.1 ml/kg of saline instead of dexamethasone. The dose of 0.5 and 1.0 mg/kg of dexamethasone significantly reduced emetic episode. The degree of sedation determined by visual sedation scoring was not influenced by dexamethasone pretreatments. In addition, the values of complete blood counts and blood chemistry did not show significant changes and were within normal ranges before and the day after experiment. These results show that the doses of 0.5 and 1.0 mg/kg of dexamethasone are useful and safe method to prevent emetic episode inducing by medetomidine in dogs, without evidence of any clinically relevant influences.

• Korean Journal of Medicinal Crop Science
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• v.7 no.1
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• pp.7-10
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• 1999

The effects of storage temperature and periods as pretreatments on direct somatic embryogenesis or shoot development in liquid culture of leaves, stems and petioles of Rehmannia glutinosa and Scrophularia buergeriana were investigated. Proper storage Temperature for Rehmannia glutinosa was $8^{\circ}C$ and the leaf stock could be stored up to 12 weeks. In Scrophularia buergerjana. shoots were developed from the 20 week-stored petiole and stem at $8^{\circ}C$. In general, $8^{\circ}C$ was considered the most effective storage temperature in terms of storage cost.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.3
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• pp.257-262
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• 2015

It is well known that cigarette smoke can cause erectile dysfunction by affecting the penile vascular system. However, the exact effects of nicotine on the corpus cavernosum remains poorly understood. Nicotine has been reported to cause relaxation of the corpus cavernosum; it has also been reported to cause both contraction and relaxation. Therefore, high concentrations of nicotine were studied in strips from the rabbit corpus cavernosum to better understand its effects. The proximal penile corpus cavernosal strips from male rabbits weighing approximately 4 kg were used in organ bath studies. Nicotine in high concentrations ($10^{-5}{\sim}10^{-4}M$) produced dose-dependent contractions of the corpus cavernosal strips. The incubation with $10^{-5}M$ hexamethonium (nicotinic receptor antagonist) significantly inhibited the magnitude of the nicotine associated contractions. The nicotine-induced contractions were not only significantly inhibited by pretreatment with $10^{-5}M$ indomethacin (nonspecific cyclooxygenase inhibitor) and with $10^{-6}M$ NS-398 (selective cyclooxygenase inhibitor), but also with $10^{-6}M$ Y-27632 (Rho kinase inhibitor). Ozagrel (thromboxane $A_2$ synthase inhibitor) and SQ-29548 (highly selective TP receptor antagonist) pretreatments significantly reduced the nicotine-induced contractile amplitude of the strips. High concentrations of nicotine caused contraction of isolated rabbit corpus cavernosal strips. This contraction appeared to be mediated by activation of nicotinic receptors. Rho-kinase and cyclooxygenase pathways, especially cyclooxygenase-2 and thromboxane $A_2$, might play a pivotal role in the mechanism associated with nicotine-induced contraction of the rabbit corpus cavernosum.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.5
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• pp.379-383
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• 2009

Nitric oxide (NO), a diffusible gas, is produced in the central nervous system, including the spinal cord dorsal horn and the trigeminal nucleus, the first central areas processing nociceptive information from periphery. In the spinal cord, it has been demonstrated that NO acts as pronociceptive or antinociceptive mediators, apparently in a concentration-dependent manner. However, the central role of NO in the trigeminal nucleus remains uncertain in support of processing the orofacial nociception. Thus, we here investigated the central role of NO in formalin (3%)-induced orofacial pain in rats by administering membrane-permeable or -impermeable inhibitors, relating to the NO signaling pathways, into intracisternal space. The intracisternal pretreatments with the NO synthase inhibitor L-NAME, the NO-sensitive guanylate cyclase inhibitor ODQ, and the protein kinase C inhibitor GF109203X, all of which are permeable to the cell membrane, significantly reduced the formalin-induced pain, whereas the membrane-impermeable NO scavenger PTIO significantly enhanced it, compared to vehicle controls. These data suggest that an overall effect of NO production in the trigeminal nucleus is pronociceptive, but NO extracellularly diffused out of its producing neurons would have an antinociceptive action.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.21-25
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• 1987

In order to obtain a basic understanding of the storage of Satsuma mandarin sacs, the canned sacs were stored at room temperature from Feb. 20 to June 20(4 months), after dipping in chlorine solution and pasteurization as a pretreatment before canning. In general, the brix, acidity and pH of the sacs were almost not affected by the chlorine treatment ana a variety of pasteurization temperatures during storage. The broken rate was apperently increased by chlorine treatment, especially in the early stage of storage. However, the broken sacs were partially recovered in the end of storage. The contents of total carotenoid were almost not decreased by the conditions of the pretreatments during storage. The contents of vitamin C were sharply decreased between 3rd and 4th month of storage time on all sample. As a result, the decrement of vitamin C in canned sacs was caused by storage temperature rather than the condition of the pretreament.

• Resources Recycling
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• v.26 no.3
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• pp.32-38
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• 2017

For the massive recycling of mine tailings, which are an inorganic by-product of mining process, in the field of civil engineering, pretreatments to extract heavy metals are required. This study focuses on the use of pre-treated tailings as substitute fillers for controlled low-strength material (CLSM). As a comparative study, untreated tailing, microwave-treated tailing and magnetic separated with microwaved tailing were used in this study. Cement contents amounting to 10%, 20% and 30% by the weight of the tailings were designed. Both compressive strength and flowability for all types of mixture were satisfied with the requirements of the American Concrete Institute (ACI) Committee 229, i.e., 0.3-8.3 MPa of compressive strength and longer than 200 mm flowability. Furthermore, all mixtures showed settlements less than 1% by volume of the mix.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2413-2418
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• 2013

Forensic and legal medicine require reliable data to indicate excessive alcohol consumption. Ethanol is oxidatively metabolized to acetate by alcohol dehydrogenase and non-oxidatively metabolized to ethyl glucuronide (EtG), ethyl sulfate (EtS), phosphatidylethanol, or fatty acid ethyl esters (FAEE). Oxidative metabolism is too rapid to provide biomarkers for the detection of ethanol ingestion. However, the non-oxidative metabolite EtG is a useful biomarker because it is stable, non-volatile, water soluble, highly sensitive, and is detected in body fluid, hair, and tissues. EtG analysis methods such as mass spectroscopy, chromatography, or enzyme-linked immunosorbent assay techniques are currently in use. We suggest that nuclear magnetic resonance (NMR) spectroscopy could be used to monitor ethanol intake. As with current conventional methods, NMR spectroscopy doesn't require complicated pretreatments or sample separation. This method has the advantages of short acquisition time, simple sample preparation, reproducibility, and accuracy. In addition, all proton-containing compounds can be detected. In this study, we performed $^1H$ NMR analyses of urine to monitor the ethanol and EtG. Urinary samples were collected over time from 5 male volunteers. We confirmed that ethanol and EtG signals could be detected with NMR spectroscopy. Ethanol signals increased immediately upon alcohol intake, but decreased sharply over time. In contrast, EtG signal increased and reached a maximum about 9 h later, after which the EtG signal decreased gradually and remained detectable after 20-25 h. Based on these results, we suggest that $^1H$ NMR spectroscopy may be used to identify ethanol non-oxidative metabolites without the need for sample pretreatment.