• International Journal of Oral Biology
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• v.36 no.2
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• pp.43-50
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• 2011

Voltage dependent calcium channel (VDCC), one of the most important regulator of $Ca^{2+}$ concentration in neuron, play an essential role in the central processing of nociceptive information. The present study investigated the antinociceptive effects of L, T or N type VDCC blockers on the formalin-induced orofacial inflammatory pain. Experiments were carried out on adult male Sprague-Dawley rats weighing 220-280 g. Anesthetized rats were individually fixed on a stereotaxic frame and a polyethylene (PE) tube was implanted for intracisternal injection. After 72 hours, 5% formalin ($50 \;{\mu}L$) was applied subcutaneously to the vibrissa pad and nociceptive scratching behavior was recorded for nine successive 5 min intervals. VDCC blockers were administered intracisternally 20 minutes prior to subcutaneous injection of formalin into the orofacial area. The intracisternal administration of 350 or $700{\mu}g$ of verapamil, a blocker of L type VDCC, significantly decreased the number of scratches and duration in the behavioral responses produced by formalin injection. Intracisternal administration of 75 or $150 \;{\mu}g$ of mibefradil, a T type VDCC blocker, or 11 or $22\; {\mu}g$ of cilnidipine, a N type VDCC blocker, also produced significant suppression of the number of scratches and duration of scratching in the first and second phase. Neither intracisternal administration of all VDCC blockers nor vehicle did not affect in motor dysfunction. The present results suggest that central VDCCs play an important role in orofacial nociceptive transmission and a targeted inhibition of the VDCCs is a potentially important treatment approach for inflammatory pain originating in the orofacial area.

• Journal of ILASS-Korea
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• v.6 no.1
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• pp.25-34
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• 2001

Several efforts to meet the exhaust gas regulation have been undertaken by many researchers in recent years. Main researches are on development of design techniques of intake port and combustion chamber, atomisation of fuel and precise control of air-fuel ratio, post-treatment of exhaust gas and so on. Engine technology is changed from PFI to GDI to correspond with exhaust gas regulation. GDI technique makes it possible to preserve lean air-fuel ratio and control accurate air-fuel ratio. Nevertheless, It is not cleared that information of spray characteristics and atomization process are very dependent on fluctuation of pressure and change of temperature in intake stroke. In this study, a constant volume combustion chamber is manufactured to investigate various fluctuations of in-cylinder pressure for injection duration. It is taken photographs of injection process of conventional GDI injector using PMAS. Then, it was verified experimently that ambient conditions as temperature and pressure of combustion chamber have effects on process of spray growth and atomization of fuel.

• Journal of Mechanical Science and Technology
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• v.14 no.10
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• pp.1143-1150
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• 2000

The effects of ambient conditions on vaporizing sprays from a high-pressure swirl injector were investigated by an exciplex fluorescence method. Dopants used were 2% fluorobenzene and 9% DEMA (diethyl-methyl-amine) in 89% solution of hexane by volume. In order to examine the behavior of liquid and vapor phases inside of vaporizing sprays, ambient temperatures and pressures similar to engine atmospheres were set. It was found that the ambient pressure had a significant effect on the axial growth of spray, while ambient temperature had a great influence on the radial growth. The spatial distribution of vapor phase at temperatures above 473K became wider than that of liquid phase after half of injection duration. From the analysis of the area ratio for each phase, the middle part (region II) in the divided region was the region which liquid and vapor phases intersect. For liquid phase, fluorescence-intensity ratio was greatly changed at lms after the start of injection. However, the ratio of vapor phase was nearly uniform in each divided region throughout the injection.

• Journal of Institute of Convergence Technology
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• v.8 no.1
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• pp.9-13
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• 2018

The purpose of this study is to investigate the liquid- and vapor-phase spray characteristics, such as spray tip penetration and spray angle using gasoline direct injection (GDI) injector with multi-hole. The vapor-phase spray was captured by the Schlieren visualization system, which consists of high-speed camera, LED lamp, concave mirrors, and knife-edge. The liquid-phase spray was visualized by Mie-scattering techniques. Both spray images of vapor- and liquid-phase were visualized under 373 K of ambient temperature, 1 bar of ambient pressure, and 100/200 bar of injection pressure. The energizing duration was fixed at 1.5 ms. From the analysis of experimental results, it revealed that the increased injection pressure induced an early vaporization due to the improvement of droplet atomization. The spray tip penetration and spray angle in vapor-phase were higher than those in liquid-phase. The difference in the spray tip penetration between vapor- and liquid-spray gradually increased with the time elapsed after the injection. Even with the spray angle characteristics, it was found that the difference between the spray angle of liquid and vapor spray gradually grew after they entered steady-state conditions.

• Journal of Dental Anesthesia and Pain Medicine
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• v.20 no.4
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• pp.233-240
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• 2020

Background: Palatal injection of local anesthetics is the most painful injection. To obviate the need for palatal injections, local anesthetic agents with diffusibility are being investigated. Hence the present study was designed to analyze the anesthetic efficacy of 2% lidocaine hydrochloride (HCl) with 1:100,000 adrenaline and 4% articaine hydrochloride (HCl) with 1:100,000 adrenaline using single buccal infiltration for the extraction of maxillary premolars. Methods: A prospective, double-blind, crossover, randomized clinical study was performed on 60 consecutive systemically healthy patients with an age range of 15-30 years, requiring extraction of asymptomatic bilateral maxillary premolars for orthodontic purposes. They received 1ml buccal infiltration of 4% articaine HCl with 1:100,000 adrenaline on one side and 2% lidocaine HCl with 1:100,000 adrenaline on the other side. The extraction procedure on either side was scheduled 14 days apart. Parameters assessed were the time of onset of anesthesia, intraoperative discomfort, hemodynamic parameters, and the duration of analgesia. Analysis of the data was done using the Mann-Whitney test, the Wilcoxon test, the Kruskal-Wallis ANOVA test, and the chi-square test. Statistical significance was established at P < 0.05. Results: Articaine showed a faster time of onset and longer duration of analgesia than lidocaine. However, the difference in the intraoperative discomfort and hemodynamic parameters was statistically insignificant. Conclusion: Within the limitations of the study, it can be concluded that the extraction of maxillary premolars can be performed with a single buccal infiltration of 2% lidocaine HCl with 1:100,000 adrenaline, which is one of the most commonly used local anesthetic agent.

• Archives of Plastic Surgery
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• v.37 no.6
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• pp.795-800
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• 2010

Purpose: According to various medical publications, it is believed that epinephrine should not be injected in fingers. However numerous articles show the successful use of local anesthetic with epinephrine in the digits. Epinephrine-mixed lidocaine solution enables to maintain a bloodless field for operation and provides long duration of local anesthesia when patient was wide awake. Methods: From May 2009 to December 2009, ten patients underwent flexor tendon reconstruction with local anesthesia using epinephrine. No tourniquet was necessary. Before operation, all patients were injected with local anesthetics using 1% lidocaine 20 mL and 0.1% epinephrine 0.1 mL. Results: There was no case of digital necrosis nor gangrene in the epinephrine injection. All 10 patients actively could move the finger through a full range of motion. All procedures were performed without sedation nor tourniquet and we could obtain a good vision of operative field and patients were comfortable. The patient make his or her fingers move through a full range of active motion before the skin is closed. Phentolamine was not required to reverse the vasoconstriction in any patients. Conclusion: The assertation that epinephrine should not be injected into the fingers is clearly no longer valid. The epinephrine injection allowed the authors to adjust flexor tendon surgery without risks associated with general anesthesia. It also enables to ensure longer anesthetic duration and bloodless operative field, and prevent post operative complications. In case of flexor tendon surgery, the use of epinephrine injection is recommended because of the advantages of local anesthesia.

• Journal of Menopausal Medicine
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• v.24 no.3
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• pp.196-203
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• 2018

Objectives: This study was aimed to establish the most effective premature ovarian failure (POF) mouse model using Cyclophosphamide (CTX), busulfan (Bu), and cisplatin considering treatment duration of anticancer drugs and natural recovery time. Methods: POF was induced by intraperitoneally injecting CTX (120 mg/kg)/Bu (12 mg/kg) for 1 to 4 weeks or cisplatin (2 mg/kg) for 3 to 14 days to C57BL/6 female mice aged 6 to 8 weeks. Controls were injected with equal volume of saline for the same periods. Body weight was measured every week, and ovarian and uterine weights were measured after the last injection of anticancer drug. To assess ovarian function, POF-induced mice were superovulated with pregnant mare serum gonadotropin and human chorionic gonadotropin, and then mated with male. After 18 hours, zygotes were retrieved and cultured for 4 days. Finally, the mice were left untreated for a period of times after the final injection of anticancer drug, and the time for natural recovery of ovarian function was evaluated. Results: After 2 weeks of CTX/Bu injection, ovarian and uterine weights, and ovarian function were decreased sharply. Cisplatin treatment for 10 days resulted in a significant decrease in ovarian and uterine weight, and ovarian function. When POF was induced for at least 2 weeks for CTX/Bu and for at least 10 days for cisplatin, ovarian function did not recover naturally for 2 weeks and 1 week, respectively. Conclusions: These results suggest that CTX/Bu should be treated for at least 2 weeks and cisplatin for at least 10 days to establish the most effective primary ovarian insufficiency mouse model.

• Health Policy and Management
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• v.20 no.1
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• pp.125-136
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• 2010

Objectives: The purpose of this study is to analyze the proportion of fundus examination of DM patients for preventing microvascular complication and to examine the factors related to fundus examination in DM patients. Methods: This study used 2005 Korean national health and nutrition survey data. We selected all 1,129 diabetes mellitus patients from the data. And we choose 8 factors related to diabetes mellitus patients. These are sex, age group, type of residential area(rural or urban), education level, income level, comorbidity with hypertension, current insulin use, and duration of suffering from DM. We have analysed these factors by whether he had been examined fundus or no through Chi-square and logistic regression analysis. Results: Female DM patients have tendency to get more fundus examination than Male DM patients. And Young patients, patients who live in urban area, well educated patients, high income patients, comorbidity with hypertension, patients have got the insulin injection, patients have long duration of suffering from DM are to get more fundus examination. According to multivariate logistic regression analysis, sex and education level, income level, and duration of suffering from DM, comorbidity with hypertension, patients have got the insulin injection are significant factors on fundus examination for prevent microvascular diabetes mellitus complications. Conclusions and Discussion: We have concluded that physicians and policy makers should consider to fundus examination especially of man and DM patients who have more shorter disease period and low educated patients and low incomed patients and patients who have taken insulin therapy.

• The Korean Journal of Pain
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• v.3 no.2
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• pp.119-124
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• 1990

Reiestad and Stromskag recently introduced the interpleural installation of local anesthetic solutions as a technique for the management of postoperative pain in patients undergoing cholecystectomy, renal surgery, and breast surgery. This study was done to manage postoperative pain in the patients undergoing unilateral upper-abdominal surgery and thoracotomy. Twenty patients received 0.5% bupivacaine 20 ml with epinephrine (Children, received 10 ml). Results were as follows: 1) Analgesic effects appeared in 15.56 minutes; mean analgesic duration from the initial intrapleural injection was 10.5 hours. 2) Blood pressure increased more after the operation than before the operation. Blood pressure before injection of bupivacaine was highest (p<0.01). Heart rate was increased before injection and 10 minutes after injection of 0.5% bupivacaine (p<0.05). 3) The values of $PaCO_2$, were improved from $41.7{\pm}2.02\;mmHg$ ($PaCO_2$), $85.2{\pm}2.41\;mmHg$ ($PaO_2$) to $37.8{\pm}2.41\;mmHg$ ($PaCO_2$), $107.0{\pm}7.86\;mmHg$ ($PaO_2$) respectively (p<0.01). 4) Complication such as pneumothorax, atelectasis and CNS toxicity did not appear. 5) Intrapleural administration of local anesthetics after unilateral upper-abdominal and thoracic surgery provided a satisfactory pain control.

• Clinics in Shoulder and Elbow
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• v.26 no.1
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• pp.64-70
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• 2023

Background: This study aimed to analyze the efficacy of single-dose corticosteroid injection (CSI) administered at 6 weeks postoperative to treat stiffness following arthroscopic rotator cuff repair (ARCR). Methods: In this prospective, multicentric, case-control study, post-ARCR stiffness at 6 weeks was treated with either a single dose of intra-articular CSI (CSI group) or physical therapy with oral analgesics (non-CSI group). Pain intensity according to visual analog scale (VAS), functional outcome using the Constant Murley Shoulder Score, time to return to activities of daily living (ADLs), and retear rate were recorded at 6 weeks, 9 weeks, 12 weeks, 6 months, 12 months, and 18 months postoperatively in both groups. Results: A total of 149 patients (54.5%) in the CSI group and 124 patients (45.5%) in the non-CSI group were included in this study. Pain and function were significantly better in the CSI group at 9-week, 12-week, and 6-month (P<0.001) follow-up, whereas they were not significantly different when the groups were compared at 12- and 18-month follow-up. The mean duration to return to ADLs was significantly shorter (P<0.001) in the CSI group. The incidence of retears was not significantly different (P=0.36) between groups at the end of 18 months of follow-up. Conclusions: Single-dose intra-articular CSI administered at 6 weeks postoperative to treat post-ARCR stiffness significantly improved pain, function, and duration of return to ADLs without increasing the risk of retears compared to patients who did not receive intra-articular CSI. Level of evidence: III.