• Archives of Pharmacal Research
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• v.8 no.4
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• pp.205-211
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• 1985

The distribution of local anesthetics between the hydrocarbone interior and surface area of the lipid bilayer of liposomal membrane was calculated employeg fluorescence probe technique. The quenching of fluorescence probe technique. The quenching of fluorescence probe technique. The quenching of fluorescence of 12-(9-anthroyl) stearic acid and N-octadecyl naphthyl-2-amini-6-sulfonic acid by the local anesthetics in liposomal system was used to calculate the distribution. The Stern-Volmer equation was modified and employed for this calculation. The results showed that procaine hydrocloride and benzocaine were mainly distributed on the surface area of the lipid bilayer of the liposoal membrane, while tetracaine hydrochloride penetrated effectively into the hydrocarbon interior and showed even distribution in the lipid bilayer.

• The Korean Journal of Malacology
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• v.25 no.1
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• pp.15-22
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• 2009

Because it is known that bivalve hearts contain various modulatory systems activated by neuroendocrine substances, it was examined whether different classes of endogenous and synthetic drugs of neuroendocrinological importance can influence cardiac functions of the Pacific oyster Crassostrea gigas. Cholinergically active agents acetylcholine and carbachol increased heart rates while diminishing cardiac contractility. Adrenergically active substances norepinephrine (NE) and epinephrine (Epi) also induced heart rate increase and contractility decrease. An $\alpha_1$-adrenergic receptor-selective agonist phenyephrine (PE) failed to modulate either parameter. The Epi-induced heart rate increase and contractile depression were both blocked significantly by non-selective $\beta_1/\beta_2$-adrenergic antagonist propranolol. A $\beta_1$-selective antagonist atenolol prevented Epi-induced heart rate decrease but not the contractile depression, suggesting possible $\beta_2$ receptors for Epi-induced contractile depression. The three autacoids examined exerted discrete responses: histamine increased heart rate and depressed contraction; $\gamma$-amino-butyric acid increased both parameters; serotonin failed to change either parameter. The 5 piscine anesthetic agents examined, MS-222, benzocaine, quinaldine, urethane, pantocaine and pentobarbital, all failed to influence the cardiac function of oysters. Collectively, activities of neuroendocrinologically acting agents in mammals showed unexpected and distinct activities from those in mammalian cardiovascular systems. These results obtained from substances of different physiological functions can serve as a basis for understanding neuroendocrine control of the heart function in Pacific oyster.

• Journal of The Korean Society of Clinical Toxicology
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• v.8 no.1
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• pp.1-6
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• 2010

Methylene blue is a very effective reducer of drug-induced methemoglobinemia. It has dose-dependent oxidation or reduction properties. In most cases, a dose of 1 to 2 mg/kg IV given over 5 minutes and immediately followed by a 15- to 30-mL fluid flush to minimize the local pain is both effective and relatively safe. The onset of action is quite rapid, and the effects are usually seen within 30 minutes. The dose may be repeated after 30 to 60 minutes and then every 2 to 4 hours as needed. The total dose should not exceed 7 mg/kg as a single dose or 15 mg/kg within 24 hours. Repeated treatment may be needed for treating compounds that have prolonged elimination or those compounds that undergo enterohepatic recirculation (e.g., dapsone). Methylene blue can cause dose-related toxicity. At high doses, methylene blue can also induce an acute hemolytic anemia and rebound methemoglobinemia. The reasons for treatment failure with methylene blue include ineffective GI decontamination, the existence of other forms of hemoglobin (e.g., sulfhemoglobin), a low or high dose of methylene blue and the toxicokinetics of some agents, such as aniline, benzocaine or dapsone.

• Journal of Medicine and Life Science
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• v.18 no.1
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• pp.20-23
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• 2021

Methemoglobin is generated by the oxidation of ferrous iron to ferric iron within a hemoglobin molecule. Methemoglobin is unable to bind and transport oxygen, resulting in methemoglobinemia, which can lead to fatal tissue hypoxia. The most common cause of methemoglobinemia is poisoning by oxidizing agents such as dapsone, benzocaine, and primaquine. However, methemoglobinemia can also be caused by normal dietary sources. We present two cases of methemoglobinemia that developed after a normal diet in two male patients. In this case report, the patients suddenly developed dyspnea and cyanosis after eating the same meal. They had no history of suspected poisoning, such as the use of drugs, exposure to chemicals, or gas inhalation. Their symptoms did not improve even after a high dose of oxygen was administered; further, an abnormal 'oxygen saturation gap' was observed. Because of CO-oximetry, the methemoglobin levels of the patients were 50.0% and 46.6%, respectively. We administered methylene blue (1 mg/kg), and the patients recovered completely without any complications. Emergency physicians should, therefore, be aware that methemoglobinemia can also be caused by normal dietary sources. In addition, if the source and route of contamination are unclear, an epidemiological investigation should be conducted.

• Journal of dental hygiene science
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• v.18 no.5
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• pp.319-326
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• 2018

Although scaling is the primary method for improving oral health, it is also associated with dental fear. The objective of this study was to empirically verify whether the use of gel anesthetic within the gingival sulcus during scaling relieves pain and improves other factors. A total of 128 patients scheduled to undergo scaling at a dental clinic of a general hospital located in the Gyeonggi Province, between July 2014 and July 2015, were enrolled in the study. The participants underwent scaling following the application of 20% benzocaine gel or placebo gel anesthetic within the gingival sulcus, and the data was collected using a questionnaire. There was a significant difference in the severity of pain, participant satisfaction, perceived sensitivity, overall discomfort, and fear of scaling between the two groups. The two groups were compared in terms of perceived need for gel anesthesia, willingness to pay for anesthesia costs, and willingness to receive scaling in the future. There were significant differences in all the three parameters depending on whether gel anesthesia was used or not. There were significant differences between the two groups in perceived sensitivity immediately after scaling and one day after scaling, with no difference seen one week after scaling. With regards to overall discomfort over time, there were significant differences between the two groups immediately after scaling. Based on these findings, we expect that application of gel anesthetic within the gingival sulcus during scaling will reduce pain, perceived sensitivity, overall discomfort, and fear of scaling with increased satisfaction.