• Title/Summary/Keyword: The $\alpha$-effect

Search Result 6,750, Processing Time 0.034 seconds

Effects of Clonidine on the Negative Chronotropic Response Induced by Vagal Stimulation in the Rat

  • Hong, Sung-Cheul;Huh, Kyung-Hye;Chung, Joon-Ki;Park, Mi-Sun
    • Archives of Pharmacal Research
    • /
    • v.11 no.1
    • /
    • pp.65-73
    • /
    • 1988
  • The effects of clonidine on the negative chronotropic response induced by stimulation of vagus nerve were studied in the presence of propranolol in reserpinized and anesthetized rats. When the heart rate was decreased by stimulation of the vagus nerve, clonidine significantly inhibited vagally induced heart rate decrease (negative chronotropic response) in dose dependent manner. This inhibitory effect of clonidine was virtually abolished by phentolamine, ${\alpha}_1-\;and\;{\alpha}_2-adrenoceptor$ antagonist, and partially antagonized by prazosin, ${\alpha}_1-adrenoceptor$ antagonist. On the other hand, when the heart rate was decreased by the infusion of bethanechol, a muscarinic parasympathetic stimulant, clonidine had no effect on the bethanechol-induced heart rate decrease. These results suggest that clonidine inhibits vagally induced negative chronotropic response by activation of presynaptic ${\alpha}-adrenoceptors$ located on the parasympathetic cholinergic nerve terminal in the heart and this effect of clonidine is more related to ${\alpha}_2-adrenoceptors$ than ${\alpha}_1-adrenoceptors$.

  • PDF

Immune Enhancing Effect of Boummyunyuck-dan (보음면역단의 면역 증강 효과)

  • 김태균;문석재;원진희;김동웅;이종덕;문구
    • The Journal of Korean Medicine
    • /
    • v.24 no.1
    • /
    • pp.54-64
    • /
    • 2003
  • Objective : To investigate immune enhancing effects of Boummyunyuck-dan (BMD) Methods : In this study I investigated the effect of BMD on cell proliferation and viability. In addition, I investigated production of cytokines (IL-2, IL-4 and $IFN-{\gamma}$), NO, and $TNF-{\alpha}$ in human T-cell leukemia, MOLT-4 cells. The cells were cultured for 24h in the presence or absence of BMD. Result : BMD increased the cell viability by 15% (P<0.05) and enhanced IL-2, IL-4 and $IFN-{\gamma}$ production compared with media control in a dose-dependent manner (P<0.01) at 24h. BMD also increased mRNA and protein expression levels of $IFN-{\gamma}$ in MOLT-4 cells. In addition, I also assessed the effects of BMD on production of NO and $TNF-{\alpha}$ from the peritoneal macrophages because NO and $TNF-{\alpha}$ as a potent macrophage-derived immune reaction regulatory molecule has received increasing attention. However, BMD had no effect on NO and $TNF-{\alpha}$ production in the cells. Conclusion : These data indicate that BMD has some immune-enhancing effect, and that its action may be due to the proliferation and cytokine production of T cells.

  • PDF

Studies on Artificial Control of Parturition in Korean Native Goats I. The Effect of Prostaglandin $F_2\alpha$ to Induce Parturition (한국 재래산양 분만의 인위적 조절에 관한 연구 I. Prostaglandin $F_2\alpha$ 투여에 의한 분만유기 효과)

  • 윤창현;민관식;장규태;오석두
    • Korean Journal of Animal Reproduction
    • /
    • v.15 no.2
    • /
    • pp.109-115
    • /
    • 1991
  • This experiment was conducted to find out the time to farrowing induction after PGF2$\alpha$ treatment, the rate of farrowing induction, the effect of kids born by the induced farrowing on birth weight and development with study on artificial control of parturition in Korean native goats. A total of 24 pluriparous goats were offered for this experiment. The animals were divided into 4 goats per treatment by administration time(142, 145 or 148 day of pregnancy) and dosage (5 or 7.5mg). The results obtained in this experiments were as follows : 1. The effect of synchronization of estrus was induced 23 goats(95.1%), 16 goats(66.6%) in the 1st treatment and 7 goats(28.5%) in the 2nd treatment PGF2$\alpha$ and exhibited estrus at a mean interval of 75$\pm$5 hours after PGF2$\alpha$ injection. 2. The time to farrowing induction after PGF2$\alpha$ treatment on day 145 or 148 was significantly(P<0.01) shorter than that of the 5mg treatment, but there was no significant difference(P>0.01). 3. Parturition was induced in all goats(100%) treated 5 or 7.5mg of PGF2$\alpha$ on day 148 and 7.5mg of PGF2$\alpha$ on day 145, but was induced 75% in treatment with 5mg of PGF2$\alpha$ on day 145 and 5 or 7.5mg of F2$\alpha$ on day 142. 4. The birth weight and development of kids induced farrowing was heaviest (P<0.01) on days 148 among treatment, but there was no significant difference in dosage.

  • PDF

The Effects of ALPHA-NUMERIC Brand Name on the Functional Sportswear, for its Suitability, Brand Personality, and Attitude (기능성 스포츠 의류제품의 알파누메릭(Alpha-Numeric) 브랜드 네임이 제품의 적합성, 브랜드 개성 및 태도에 미치는 영향)

  • Suh, Hyun-Suk;Na, Youn-Kue;Sun, Jin-Young
    • Fashion & Textile Research Journal
    • /
    • v.11 no.4
    • /
    • pp.556-565
    • /
    • 2009
  • This study investigates the effect of Alpha-numeric brand name on the product suitability, brand personality, and attitude. To do that we have chosen the functional sportswear, knowing the fact that the Alpha-numeric brand names are not hard to find in this industry. The changes have been made to Alpha-numeric names, such as the usage/non-usage of number, the size of number being used, the writing method, and the different typeface to suit for the study purpose. The results indicate that the Alpha-numeric brand names do have the effect on increasing the fitness for the product's brand. The bigger number and the cursive script will improve the product's suitability. The customers form positive attitude and favorability on the Alpha-numeric brand name compared to the regular brand name in this industry. The contribution of the study is to dig out the distinction of the communicational effects on the customers when the Alpha-numeric brand names take on the different forms. Therefore the current study enlights the practical value of Alpha-numeric brand name as part of the branding strategy.

IN VITRO STEM CELL SUPPRESSION OF MACROPHAGE INFLAMMATORY $PROTEIN-1{\alpha}$ (Macrophage Inflammatory $Protein-1{\alpha}$의 조혈간세포(造血幹細胞) 억제 작용에 관한 실험적 연구)

  • Suh, Ki-Hang;Ko, Seung-O;Shin, Hyo-Keun;Kim, Oh-Whan
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.18 no.2
    • /
    • pp.286-297
    • /
    • 1996
  • The proliferation of bone marrow stem cell compartment is thought to be under both positive and negative controls by cytokines and colony stimulation factors. Macrophage inflammatory $protein-1{\alpha}(MIP-1{\alpha})$ has been assessed for its potential to protect hematopoietic stem cells from cytotoxic effects of a cycle-specific antineoplastic agents. We have tested the ability of $MIP-1{\alpha}$ to suppress the proliferation of stem cell line Du.528.101 in variety of active status by using $[^{3}H]-thymidine$ incorporation test. The results were as follows. 1. The effect of $MIP-1{\alpha}$ on steady-state Du.528.101 cell represented the cell growth suppression at the concentration of 10, 50, 100nM of $MIP-1{\alpha}$(P<0.001). 2. $MIP-1{\alpha}$ stimulated the proliferation of Du.528.101 cells previously treated with IL-1 at the concentration of 5, 50nM of $MIP-1{\alpha}$(P<0.01). 3. The suppression effect of MIP-1 on Du.528.101 cells at the concentration of 5, 50nM was shown when cells were treated with $MIP-1{\alpha}$ before activation with $IL-1{\beta}(P<0.01)$. 4. The growth rate of synchronized cells were slower than that of non-synchronized ones, and $MIP-1{\alpha}$ represented the similar suppression effect on both synchronized and non-synchronized cells.

  • PDF

The α-Effect and Mechanism of Reactions of Y-Substituted Phenyl Benzenesulfonates with Hydrogen Peroxide Ion

  • Im, Li-Ra;Um, Ik-Hwan
    • Bulletin of the Korean Chemical Society
    • /
    • v.30 no.10
    • /
    • pp.2393-2397
    • /
    • 2009
  • Second-order rate constants ($k_{HOO}$‒) have been measured spectrophotometrically for nucleophilic substitution reactions of Y-substituted phenyl benzenesulfonates (1a-g) with $HOO^-$ ion in $H_2O$ at $25.0\;{\pm}\;0.1\;{^{\circ}C}$. The Br$\phi$nsted-type plot is linear with ${\beta}_{lg}$ = ‒0.73. The Hammett plot correlated with with ${\sigma}^-$ constants results in much better linearity than ${\sigma}^o$ constants, indicating that expulsion of the leaving group occurs in the rate-determining step (RDS) either in a stepwise mechanism or in a concerted pathway. However, a stepwise mechanism in which departure of the leaving group occurs in the RDS has been excluded since $HOO^-$ ion is more basic and a poorer leaving group than the leaving Y-substituted phenoxide ions. Thus, the reactions of 1a-g with $HOO^-$ ion have been concluded to proceed through a concerted mechanism. The $\alpha$-nucleophile $HOO^-$ ion is more reactive than its reference nucleophile $OH^-$ ion although the former is ca. 4 p$K_a$ units less basic than the latter (i.e., the $\alpha$-effect). TS stabilization through intramolecular H-bonding interaction has been suggested to be irresponsible for the $\alpha$-effect shown by $HOO^-$ ion, since the magnitude of the $\alpha$-effect is independent of the electronic nature of substituent Y in the leaving group. GS destabilization through desolvation of $HOO^-$ ion has been concluded to be responsible for the $\alpha$-effect found in the this study.

Studies on the Polymeric Surfactants (IV);Synthesis Activities of Sodium ${\alpha}-Sulfo$ Fatty Acid Allyl Ester Oligomers (고분자(高分子) 계면활성제(界面活性劑)에 관한 연구(硏究) (제(第) 4 보(報));나트륨 알파술폰 지방산(脂肪酸) 알릴에스테르 올리고머류(類)의 계면활성(界面活性))

  • Lee, Seung-Yeoll;Kim, Jin-Heon;Nam, Ki-Dae
    • Journal of the Korean Applied Science and Technology
    • /
    • v.6 no.2
    • /
    • pp.53-58
    • /
    • 1989
  • A series of four sodium ${\alpha}-sulfo$ fatty acid allylester oligomers such as sodium ${\alpha}-sulfo$ lauric acid allylester oligomer, sodium ${\alpha}-sulfo$ myristic acid allyl ester oligomer, sodium ${\alpha}-sulfo$ palmitic acid allyl ester oligomer and sodum ${\alpha}-sulfo$ stearic acid allyl ester oligomer were examined for surface tension, defloculation effect and emulsifying power. Also critical micelle concentration (cmc) was evaluated. Consequently, these sodium allyl ${\alpha}-sulfo$ aliphatic carboxylate aligomers show o/w type emulsifying agent and dispersion effect in 1g/100ml soulution.

Allelopathic Effect of Volatile Extracts from Eupatorium rugosum (서양등골나물 휘발성 추출물의 알레로파시 효과)

  • Kil, Ji-Hyon;Shim, Kew-Cheol;Lee, Ho-Jun
    • The Korean Journal of Ecology
    • /
    • v.28 no.3
    • /
    • pp.135-139
    • /
    • 2005
  • This study was carried out to find the allelopathic effect of volatile materials released from Eupatorium rugosum. The GC method was employed for analysis of volatile materials from E. rugosum and 49 chemical substances were identified such as $\beta$-caryophyllene, $\alpha$-terpinenol, chamazulene, bornyl acetate, $\alpha$-pinene, etc. including unidentified three chemicals. Germination test in Phaseolus radiatus was done to find the inhibition effect of volatile materials using some chemicals which were proved to be important component or much amounts ones in E. rugosum. It was strongly inhibited by linalool and terpinen-4-ol. Seedling elongation and radicle growth of that were proportionally inhibited by the concentration of the essential oil, especially $\alpha$-pinene and bornyl acetate. Biomass of receptor plant was slightly decreased more than 58 ${\mu}l$ of the extract in case of $\alpha$-pinene, while it was decreased more than 19 ${\mu}l$ of that in bornyl acetate but it was shown non-significant. From the above results, it was found that volatile materials from E. rugosum showed a allelopathic effect and also $\alpha$-pinene, bornyl acetate, linalool and terpinen-4-ol used in bioassay were some of major allelochemicals in germination inhibition and especially linalool and terpinen-4-ol are prominent effect on growth inhibition of other plant.

Anticancer Effect of Photodynamic Therapy using 9-Hydroxypheophorbide-$\alpha$ and 660nm Diode Laser on Human Squamous Cell Carcinoma Cell Line (인체 편평상피세포암세포주에서 9-Hydroxypheophorbide-$\alpha$와 660nm Diode 레이저를 이용한 광역학치료의 항암효과)

  • Kim Han-Gyun
    • Korean Journal of Head & Neck Oncology
    • /
    • v.17 no.1
    • /
    • pp.3-7
    • /
    • 2001
  • Objectives: New photosensitizer 9-hydroxypheophorbide-$\alpha$(9-HpbD-$\alpha$) was derived from chlorophyll in water with peak absorption at 660nm. 9-HpbD-$\alpha$ was tested with 660 nm diode laser for the anticancer effect of photodynamic therapy. Materials and Methods: Human SNU 1041 cells were seeded into 96 well plate at a density of $$ cells/well for 24 hours. Cells were washed with media containing various concentration of 9-HpbD-$\alpha$ ranging from $0{\mu}g/ml\;to\;3.75{\mu}g/ml$. Then, laser treatment was done with 660nm diode laser ($10mW/cm^2$) at various time setting (0, 30, 60, 90, 120 minutes) and with various time interval (0, 1, 4, 6, 18 hours). The treated cells were incubated 48 hours and MTT assay was done to measure the viability of cells. Results: The viability of cells was more than 90% after laser treatment in control group. The viability of cells was decreased with increasing concentration of 9-HpbD-$\alpha$ and laser treatment time in experimental groups. The viability of cells was decreased significantly as the interval time between addition of 9-HpbD-$\alpha$ and laser irradiation was increased. Conclusion: This study shows the anticancer effect of photodynamic therapy using 9-HpbD-$\alpha$ and 660nm Diode laser on carcinoma cell line. 9-HpbD-$\alpha$ is considerd as one of new photo sensitizers in the field of photodynamic therapy.

  • PDF

The Estimation Method and Application of UV-cut effect in Lens (렌즈에서 UV 차단효과의 평가방법 및 적용)

  • Kim, Yong-Geun
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.6 no.1
    • /
    • pp.107-110
    • /
    • 2001
  • In order to estimate the UV-A line's cut efficiency it lens, it was measured the light transmittance in the 320~400nm wavelength regions. We obtained the area to integrate the light transmittance of standard CR-39 and sample in the 320~400nm wavelength regions and established ${\alpha}$, ${\beta}$ of UV-A line's cut efficiency by contrast its area. We obtained the absolute cut efficiency ${\alpha}$ CR=0.59 value of CR-39 Lens, and if ${\alpha}$ was the absolute cut efficiency value of the lens to estimate UV-A cut effect, the relative cut efficiency ${\beta}$ was $1.69{\alpha}$. It was obtained the absolute and the relative UV exclusion index through each $a=(1-{\alpha}){\times}100%$, $b=(1-{\beta}){\times}100%$.

  • PDF