• Title/Summary/Keyword: repeated dose

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Contractile Action of Barium in the Rabbit Renal Artery (가토 신동맥 평활근에서 Barium의 수축작용)

  • Jeon, Byeong-Hwa;Kim, Sahng-Seop;Kim, Se-Hoon;Chang, Seok-Jong
    • The Korean Journal of Physiology
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    • v.24 no.2
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    • pp.293-303
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    • 1990
  • The contractile action of barium $(Ba^{2+})$ was investigated in the arterial strip of rabbit renal artery. The helical strip of isolated renal artery was immersed in the Tris-buffered Tyrode's solution equilibrated with 100% $O_2$ at $37^{\circ}C$ and its isometric tension was measured. $Ba^{2+}-induced$ contraction of arterial strip was dose-dependent and its maximal tension corresponded to $92.1{\pm}4.5%$ of tension by $K^+(100\;mM)$. $Ba^{2+}-induced$ contraction did not show the tachyphylactic phenomenon in the normal Tyrode's solution. $Ba^{2+}$ induced the tonic contraction in the $Ca^{2+}-free$ tyrode's solution and that was increased by the extracellula addition of $Ca^{2+}$. During the repeated exposure of the same dose of $Ba^{2+}\;(10\;mM)$ in the $Ca^{2+}-free$ Tyrode's solution, $Ba^{2+}-induced$ contraction was progressively decreased. Even though the intracellular NE-and caffeine-sensitive $Ca^{2+}$ was depleted, $Ba^{2+}$ induced the tonic contraction. After the pretreatment of lanthnum or verapamil, $Ba^{2+}$ did not induce contraction. $Ba^{2+}-induced$contraction was suppressed by extracellular $K^+$ in the normal Tyrode's solution and that was dependent on $K^+$ concentration. Suppressive effect of $K^+\;(14\;mM)$ on the $Ba^{2+}-induced$ contraction was also dependent on the intracellular $Ca^{2+}$ concentration. From the above resuts, it is suggested that $Ba^{2+}$ activate indirectly the contractile process by promoting the mobilization of intracellular $Ca^{2+}$ and the influx of extracellular $Ca^{2+}$. It is also suggested that action of $Ba^{2+}$ on the $Ca^{2+}-activated$ $K^+$ channel can result in the depolarization of cell membrane in the rabbit renal artery.

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Natural killer cell activity of olive flounder Paralichthys olivaceus following intramuscular injection of toltrazuril derivative N-(4-(4-Fluorophenoxy)-3-methylphenyl) acetamide (톨트라주릴 합성유도체, N-(4-(4-Fluorophenoxy)-3-methylphenyl) acetamide 근육 주사에 따른 넙치의 자연살해세포(Natural killer cell) 활성 검사)

  • Sang Hyup Park;Jung Eui Kim;Jeong-wan Do;Ah Ran Kim;Yi Kyung Kim
    • Journal of fish pathology
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    • v.37 no.1
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    • pp.111-122
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    • 2024
  • This study assessed the impact of the toltrazuril derivative N-(4-(4-Fluorophenoxy)-3-methylphenyl) acetamide on natural cytotoxic cell (NCC) activity of olive flounder, Paralichthys olivaceus spleen. Five groups of fifteen olive flounder, comprising non-treatment and vehicle control groups, were randomly assigned. N-(4-(4-Fluorophenoxy)-3-methylphenyl) acetamide was injected intramuscularly at doses of 120, 150 and 200 mg/kg body weight; a total of ten injections were given over the course of 30 days. The NK activity of flounder splenic cells was evaluated against YAC-1, mouse lymphoma cells or HINAE cells with a choice of co-cultivation times of 4 or 18 hrs. In case of YAC-1 co-culture we observed a significant increase in cytotoxicity at a dose of 200 mg/kg, up to 3.06 times more than that of the control group. Only the trial with the 4 hrs co-culture produced a significant difference in the HINAE cell experiment; the experimental group at the 200 mg/kg dose exhibited the maximum cytotoxicity, demonstrating 2.3 times more cytotoxicity than the control group. Furthermore, the expression level of IL-12b was markedly induced in the group with 200 mg/kg, which was 6.62 times greater than that of the control group. In terms of the altered NK cell activity, the repeated high doses of N-(4-(4-Fluorophenoxy)-3-methylphenyl) acetamide can cause changes in the normal performance of immune function.

Advancements in the treatment of pediatric acute leukemia and brain tumor - continuous efforts for 100% cure

  • Ju, Hee Young;Hong, Che Ry;Shin, Hee Young
    • Clinical and Experimental Pediatrics
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    • v.57 no.10
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    • pp.434-439
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    • 2014
  • Treatment outcomes of pediatric cancers have improved greatly with the development of improved treatment protocols, new drugs, and better supportive measures, resulting in overall survival rates greater than 70%. Survival rates are highest in acute lymphoblastic leukemia, reaching more than 90%, owing to risk-based treatment through multicenter clinical trials and protocols developed to prevent central nervous system relapse and testicular relapse in boys. New drugs including clofarabine and nelarabine are currently being evaluated in clinical trials, and other targeted agents are continuously being developed. Chimeric antigen receptor-modified T cells are now attracting interest for the treatment of recurrent or refractory disease. Stem cell transplantation is still the most effective treatment for pediatric acute myeloid leukemia (AML). However, in order to reduce treatment-related death after stem cell transplantation, there is need for improved treatments. New drugs and targeted agents are also needed for improved outcome of AML. Surgery and radiation therapy have been the mainstay for brain tumor treatment. However, chemotherapy is becoming more important for patients who are not eligible for radiotherapy owing to age. Stem cell transplant as a means of high dose chemotherapy and stem cell rescue is a new treatment modality and is often repeated for improved survival. Drugs such as temozolomide are new chemotherapeutic options. In order to achieve 100% cure in children with pediatric cancer, every possible treatment modality and effort should be considered.

The Effects of Preemptive Analgesia of Morphine and Ketorolac on Postoperative Pain, Cortisol, $O_2$ Saturation and Heart Rate (Morphine과 Ketorolac의 선행진통법이 수술 후 통증, 코티졸, 산소포화도 및 심박동 수에 미치는 효과)

  • Seo, Yun-Ju;Yoon, Hae-Sang
    • Journal of Korean Academy of Nursing
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    • v.38 no.5
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    • pp.720-729
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    • 2008
  • Purpose: This study investigated the preemptive analgesic effects of Morphine and Ketorolac on postoperative pain, cortisol, $O_2$ saturation and heart rate for the first 24 hr after abdominal surgery. Methods: Data collection was performed from April 1 to September 30, 2006. Forty patients undergoing a gastrectomy under general anesthesia were randomly allocated to the experimental or control group. The experimental group (20 patients) was administered Morphine and Ketorolac approximately 1 hr prior to skin incision, but the control group (20 patients) was administered Morphine and Ketorolac at peritoneum closure through a patient-controlled analgesia (PCA) pump. Postoperative pain, blood pressure, heart rate, cortisol, $O_2$ saturation, frequency of the PCA button pressed and doses of additional analgesics were observed through post operative 24 hr. Collected data was analyzed using t-test, $X^2$ test, repeated measures ANOVA, and Bonferroni methods. Results: Postoperative pain, cortisol, the frequency of PCA button pressed, and dose of additional analgesics of the experimental group were significantly lower than the control group. There were no statistical differences in blood pressure, heart rate and $O_2$ saturation between the experimental group and control group. Conclusions: We concluded that administration of morphine and ketorolac at 1 hr prior to skin incision resulted in decreasing postoperative pain, but it didn't affect blood pressure, heart rate or $O_2$ saturation for 24 hr after abdominal surgery.

Chemoprevention of chemical-induced skin cancer by Panax ginseng root extract

  • Sharma, Jyoti;Goyal, Pradeep K.
    • Journal of Ginseng Research
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    • v.39 no.3
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    • pp.265-273
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    • 2015
  • Background: Cancer has emerged as a major health problem globally as a consequence to the increased longevity of the population, changing the environment and life style. Chemoprevention is a new and promising strategy for reducing cancer burden. Recently, some natural products have been identified for their chemopreventive activity to reduce the cancer incidence. Ginseng is known for its potential to treat various ailments in human beings. The present study was designed to explore the anticancer and antioxidative potential of Panax ginseng against chemical-induced skin carcinogenesis in mammals. Methods: Skin tumors were induced in Swiss albino mice by a single topical application of 7,12-dimethylbenz(a)anthracene ($100{\mu}g/100{\mu}L$ acetone) and, 2 wks later, promoted by repeated applications of croton oil (thrice in a wk in 1% acetone) till the end of the experiment (i.e., 16 wk). Hydroalcoholic ginseng root extract at a dose of 25 mg/kg body weight/d was orally administered at the periinitiation, postinitiation, and peri-post-initiation stages. Results: Ginseng root extract treatment caused a significant reduction in tumor incidence, cumulative number of tumors, tumor yield, and tumor burden, as compared to the 7,12-dimethylbenz(a)anthracene-croton oil-treated control group. Further, biochemical assays revealed a significant enhancement in the levels of reduced glutathione, superoxide dismutase, catalase, vitamin C, and total proteins but a significant reduction in lipid peroxidation levels in both the liver and skin with ginseng root extract treatment, as compared to carcinogen-treated control group. Conclusion: These results suggest that P. ginseng has the potential to become a pivotal chemopreventive agent that can reduce cancer in mammals.

Preparation and Characterization of PVAL/PVP/Hexylene Glycol/Chitosan Hydrogels by $\gamma$-Ray ($\gamma$-선을 이용한 PVAL/PVP/헥실렌 글리콜/키토산 수화젤의 제조 및 특성)

  • 최은경;김형일;노영창
    • Polymer(Korea)
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    • v.27 no.4
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    • pp.349-357
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    • 2003
  • Hydrogels for wound dressing from a mixture of poly(vinyl alcohol) (PVAL), poly(N-vinyl pyrrolidone) (PVP), hexylene glycol (HG) and chitosan were made. The hydrogels were obtained by physical crosslinking of freezing and thawing, chemical crosslinking of irradiation, and irradiation after freezing and thawing of mixture solutions. The solid concentration of PVAL/PVP/HG/chitosan was 15 wt%. The concentration of chitosan was 0.3 wt%, and the ratio of PVAL/PVP was 6:4. The concentration of HG was in the range of 1∼5 wt%. The number of repeated freezing and thawing was in the range of 1∼3 times, and gamma irradiation doses were 25, 35 and 50 kGy. The physical properties such as gelation, water absorption and gel strength of hydrogels were examined. Gel content and gel strength decreased as HG concentration increased, whereas degree of swelling increased. Gel content and gel strength increased as irradiation dose and the number of freezing and thawing increased, whereas degree of swelling decreased. The hydrogels were evaluated for the healing effect for animals and for the antibacterial effect.

Effects of exercise on sleep EEG following caffeine administration (카페인 투여 후 운동이 수면에 미치는 효과)

  • 윤진환;이희혁
    • Journal of Life Science
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    • v.12 no.4
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    • pp.375-382
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    • 2002
  • The purpose of this experiment was to examine influence of acute exercise on nocturnal sleep which had been disrupted by caffeine(400mg$\times$3) thought the daytime. Six healthy young males aged 21.0$\times$0.2 yr with a history of low caffeine use. Subjects completed three conditions in a within-subject. At three conditions Sleep EEG were investigated: (1) nocturnal following quiet rest, (2) nocturnal sleep following the consumption of 1200mg of caffeine (3) nocturnal sleep following cycling at 60 min of 60% V $O_{2peak}$ with 1200mg of caffeine consumption. Sleep data were calculated for REM sleep, REM latency, sleep onset latency, sleep efficiency, sleep stages, SWS. Those data were analyzed using repeated-measures ANOVA of change scores. A main effect to, drug(caffeine) indicated that caffeine elicited sleep disturbance that is, TST and sleep onset latency increase and sleep efficiency and stage 4 decrease. The effects of exercise on sleep following caffeine intake generally improve sleep that is, stage 2, 3 and SWS increase and sleep onset latency decrease. A condition effect for sleep indicated sleep improvement after exercise Therefore The data supported a restorative theory of slow-wave sleep and suggest that acute exercise may be useful in promoting sleep and reducing sleep disturbance elevated by a high dose of caffeine.

Inhalation toxicity study of H menthol (Nicotine free-tob acco free)herbal cigarettes

  • Jung, Ji-Won;Cho, Sung-Dae;Cho, Jong-Ho;Kim, Kyung-Bae;Lee, Ji-Hae;Ahn, Nam-Shik;Yang, Se-Ran;Park, Joon-Suk;Lee, Yong-Soon;Kang, Kyung-Sun
    • Proceedings of the Korean Society of Food Hygiene and Safety Conference
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    • 2002.05a
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    • pp.216-216
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    • 2002
  • Generally, tobacco smoking has noxious effects such as DNA damage, lung cancer induction, coronary artery disease. Nowadays, as concerns on health and longevity increases, a huge variety of products that aim to assist to quit smoking or reduce addictive symptoms such as nicotine patches are developed and manufactured with safely evaluation, but the safety of the most recent products of interest which do not contain tobacco and nicotine, and shape cigarettes is not evaluated and guaranteed relatively. In this study, we used H-menthol(nicotine free-tobacco fine) which are widely consumed through the world to evaluate the single and repeated dose inhalation toxicity and genotoxicity of H menthol (Nicotine free-tobacco free) herbal cigarettes provided by Cigastop Ltd. in ICR mice.

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Pharmacokinetics of $[^{14}C]$DA-5018 after Subcutaneous Injection and Topical Application (피하주사 및 국소도포시 $[^{14}C]$DA-5018의 약동력학)

  • 이응두;이종진;심현주;이상득;기원배;양중익;이명걸
    • Biomolecules & Therapeutics
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    • v.5 no.1
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    • pp.82-86
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    • 1997
  • Pharmacokinetics of a new capsaicin analog, DA-5018 were evaluated after a subcutaneous injection or topical application of $[^{14}C]$--labelled or unlabelled DA-5018 to rats and rabbits. After subcutaneous injection of $_{14}$c-labelled or unlabelled DA-5018, 0.5 mg/kg (equivalent to DA-5018) to rats, the plasma total activity peaked at 2 hr with the terminal half life of 5.34 hr, however, unlabelled-DA-5018 peaked at 1 hr with the terminal half life of 1.26 hr. Moreover, the AUC (0.726 versus 0.2337g hr/ml) and MRT (7.82 versus 3.55 hr) increased significantly based on total radioactivity compared with intact DA-5018. Above data indicated that DA-5018 is extensively metabolized in rats and the terminal half- life of the metabolite(5) had a longer half-life than that of DA-5018. The cumulative percentages of biliary excretion of dose after subcutaneous injection of $[^{14}C]$DA-5018 was 40.2%, however, the value was only 2.14% when unlabelled DA-5018 was injected. After topical application of 0.1% or 0.3% $_{14}$C-labelled or unlabelled DA-5018 cream, 500 mg/kg to rats, the plasma and tissue concentrations except applied skin were under the detection limit. After consecutive 7 days topical application of unlabelled DA-5018, 0.1% and 0.3% cream to rats, the plasma concentrations were also under the detection limit. But the urinary excretion of DA-5018 was significantly increased by repeated topical administration. After topical application of unlabelled DA-5018, 0.1% and 0.3% cream to rabbits, the plasma and urine concentrations were under the detection limit. Above data indicated that the skin permeation of DA-5018 was lower and the metabolism of DA-5018 was higher in rabbits than that in rats.

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Effects of L-NAME on the Mechanical Hyperalgesia after the Development of Inflammation by Freund's Complete Adjuvant in Rat Paw (FCA에 의한 염증 유발 후 주입된 L-NAME이 기계적 통각과민에 미치는 영향)

  • Kim, Min-Kyung;Choi, Yoon;Kong, Hyun-Seok;Leem, Joong-Woo;Leem, Hang-Soo;Chung, Soo-Jin;Lee, Cheong
    • The Korean Journal of Pain
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    • v.12 no.2
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    • pp.171-176
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    • 1999
  • Background: Effect of nitric oxide on the hyperalgesia induced by inflammation is controversial. From our previous experiment, NOS inhibitor, L-NAME given during the induction period decrease mechanical hyperalgesia occured by Freund's complete adjuvant induced inflammation. In addition, we attempted to analyze the effects of L-NAME on mechanical hyperalgesia after the development of inflammation by Freund's complete adjuvant in rat paw. Methods: Male Sprague Dawley rats were divided into four groups; control (normal saline), and three different doses of L-NAME (0.1 mg, 1 mg, 10 mg). Inflammation was induced in rats by injecting 0.15 ml of Freund's complete adjuvant (FCA) intraplantarly. Rats showed typical hyperalgesia within twelve hours after injection and maintained this for about one week. Tests were done 2 days after injection of FCA. After the baseline test either L-NAME or saline was injected under light halothane anesthesia. Effect of L-NAME on hyperalgesia was assessed by measuring mechanical hyperalgesia at 15, 30, 60, 90, 120 minutes. Same experients were repeated on normal rats. Results: When injected at the site of inflammation, L-NAME caused dose dependent decrease in mechanical hyperalgesia. However, normal rats also showed increased mechanical threshold after L- NAME injection. Conclusions: Although L-NAME reduces FCA induced mechanical hyperalgesia, this result may solely be due to inhibition of nitric oxide production and need to be further determined.

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