• Title/Summary/Keyword: Dose-rate effects

Search Result 965, Processing Time 0.029 seconds

The Effect of Surfactant on Neutrophil Apoptosis in Lipopolysaccharide Induced Acute Lung Injury in Rat (기관내 내독소 투여로 유도한 백서의 급성 폐손상 모델에서 surfactant가 호중구의 아포토시스에 미치는 영향)

  • Yoo, Ji-Hoon;Lee, Byoung-Jun;Jeong, Do-Young;Lee, Sang-Hoon;Shin, Jong-Wook;Kim, Jae-Yeol;Park, In-Won;Choi, Byoung-Whui
    • Tuberculosis and Respiratory Diseases
    • /
    • v.53 no.4
    • /
    • pp.409-419
    • /
    • 2002
  • Background : The therapeutic effects of surfactant on acute lung injury derive not only from its recruiting action on collapsed alveoli but also from its anti-inflammatory effects. Pro-apoptotic action on alveolar neutrophils represents one of the important anti-inflammatory mechanisms of surfactant. In the present study, we evaluated the effects of sufactant on the apoptosis of human peripheral and rat alveolar neutrophils. Methods : In the (Ed- the article is not definitely needed but it helps to separate the two prepositions 'in') in vitro study, human neutrophils were collected from healthy volunteers. An equal number of neutrophils ($1{\times}10^6$) (Ed-confirm) was treated with LPS (10, 100, 1000ng/ml), surfactant (10, 100, $1000{\mu}g/ml$), or a combination of LPS (1000ng/ml) and surfactant (10, 100, $1000{\mu}g/ml$). After incubation for 24 hours, the apoptosis of neutrophils was evaluated by Annexin V method. In the in vivo study, induction of acute lung injury in SD rats by intra-tracheal instillation of LPS (5mg/kg) was followed by intra-tracheal administration of either surfactant (30mg/kg) or normal saline (5ml/kg). Tenty-four hours after LPS instillation, alveolar neutrophils were collected and the apoptotic rate was evaluated by Annexin V method. In addition, changes of the respiratory mechanics of rats (respiratory rate, tidal volume, and airway resistance) were evaluated with one chamber body plethysmography before, and 23 hours after, LPS instillation. Results : in the in vitro study, LPS treatment decreased the apoptosis of human peripheral blood neutrophils (control: $47.4{\pm}5.0%$, LPS 10ng/ml; $30.6{\pm}10.8%$, LPS 100ng/ml; $27.5{\pm}9.5%$, LPS 1000ng/ml; $24.4{\pm}7.7%$). The combination of low to moderate doses of surfactant with LPS promoted apoptosis (LPS 1000ng/ml + Surf $10{\mu}g/ml$; $36.6{\pm}11.3%$, LPS 1000ng/ml +Surf $100{\mu}g/ml$; $41.3{\pm}11.2%$). The high dose of surfactant ($1000{\mu}g/ml$) decreased apoptosis ($24.4{\pm}7.7%$) and augmented the anti-apoptotic effect of LPS (LPS 1000ng/ml + Surf $1000P{\mu}g/ml$; $19.8{\pm}5.4%$). In the in vivo study, the apoptotic rate of alveolar neutrophils of surfactant-treated rats was higher than that of normal saline-treated rats ($6.03{\pm}3.36%$ vs. $2.95{\pm}0.58%$). The airway resistance (represented by Penh) of surfactant-treated rats was lower than that of normal saline-treated rats at 23 hours after LPS injury ($2.64{\pm}0.69$ vs. $4.51{\pm}2.24$, p<0.05). Conclusion : Surfactant promotes the apoptosis of human peripheral blood and rat alveolar neutrophils. Pro-apoptotic action on neutrophils represents one of the important anti-inflammatory mechanisms of surfactant.

Effects of brefeldin A on spontaneous and delayed apoptosis of human neutrophils (호중구의 자연 세포사멸 및 세포사멸 지연에 대한 Brefeldin A의 영향)

  • 김재석;이민정;이창민;이상화;배외식;곽종영
    • Journal of Life Science
    • /
    • v.12 no.4
    • /
    • pp.452-459
    • /
    • 2002
  • Neutrophil apoptosis is a constitutive process that can be enhanced or delayed by various stimuli. In this study, effect of brefeldin A (BFA), which affects biological process of secretion, on constitutive and delayed apoptosis of neutrophils was investigated. Neutrophil apoptosis was determined after culturing for 20 hr in vitro by morphological changes, annexin V staining and DNA electrophoresis. BFA increased the constitutive apoptotic rate of neutrophils in dose-dependent manner. The delay of apoptosis induced by granulocyte macrophage-colony stimulating factor and lipopolysaccharide was also blocked by 10 $\mu$M of BFA. However, this effect of BFA was less marked when neutrophils were treated with dexamethasone, interleukin-8, or dibutyryl-cAMP. Moreover, the delay of neutrophil apoptosis induced by rottlerin, a specific inhibitor of protein kinase C-$\delta$ was significantly abrogated by BFA. Although BFA-induced apoptosis was not blocked by the caspase-3 inhibitor, zDEVD-fmk, expression levels of myeloid cell leukemia-1 (Mcl-1) were down-regulated by BFA. These results suggest that derangement of vesicular protein transport may be involved in the apoptosis of neutrophils, and that the action of BFA on apoptosis is dependent on changes in the expression of Mcl-1.

A Study on Fatty Liver Syndrome in Periparturient Holstein Cows (분만전후 젖소의 지방간증에 관한 연구)

  • Choi Hee-In;Lee Joon-Sup;Lee Chang-Woo;Yun Young-Min
    • Journal of Veterinary Clinics
    • /
    • v.10 no.2
    • /
    • pp.147-155
    • /
    • 1993
  • This study was carried out to investigate the Preventive and treatment effects of mixed compound of vitamin E and selenium, and ursodeoxycholic acid on the pre-parturient and post-parturient fatty liver of high. yielding dairy cows. Thirty pregnant dairy cows(2 weeks preparturition) were divided into clinical(13cows) and subclinical(17 cows) groups based upon blood chemical values, blood serum protein levels and clinical symptoms. The clinical group was subdivided into treated clinical group(6 cows) and non-treated clinical group(7 cows). The cows(treated clinical group) with fatty liver diagnosed before parturition were dosed with mixed compound of vitamin I(1head) and selenium(10mg/head) intramuscularly once before and after parturition, respectively. These cows(treated clinical group) were also given ursodeoxycholic acid(50g/head) intramuscularly 3 times before parturition. The cows(treated clinical group) with fatty liver diagnosed after parturition were also given the same compounds as dosed to the above cows at same dose rate once or 3 times, respectively after parturition. Blood samples were collected from the cows on 4th, 7th and 2nd day of preparturition and on 1st, 7th, 14th and 20th day of postparturition. Blood chemical values(non-esterified fatty acid : NEFA) concentration, serum aspartate aminotransferase activity, serum ${\gamma}$-glutamyl transpeptidase activity, bilirubin concentration, glucose level) were checked and clinical symptoms of the cows were also observed. 1. The cows in non-treated clinical group showed severe depression, anorexia and diarrhea from prepartum period, and retained palcenta, endometritis, ketosis, abomasal displacement and mastitis after parturition. Cows in treated clinical group showed moderate depression, anorexia, diarrhea during preparturient period, but they were relieved within a week from parturition. Cows in subclinical group showed mild depression, anorexia and diarrhea after parturition, but these symptoms were not observed in prepartum period. 2. NEFA concentration, serum aspartate aminotransferase activity, serum ${\gamma}$-glutamyl transpeptidase activity and bilirubin concentration observed In the cows of treated clinical group were significantly lower than those of the cows non-treated clinical group. The blood glucose concentration of the cows in treated clinical group were higher than those of the cows in non-treated clinical group. These results indicate that the preparturient and postparturient fatty liver of high-yielding dairy cows could be reduced by dosing the animals with appropriate amounts of mixed compound of vitamin I and selenium, and ursodeoxycholic acid at proper times of the preparturition and postparturition of the dairy cows.

  • PDF

Effects of Forskolin and Cholera Toxin on the Maturation of Mouse Oocytes In Vitro (Forskolin과 Cholera Toxin이 배양중인 생쥐 난자의 성숙에 미치는 영향)

  • 김찬성;조완규
    • The Korean Journal of Zoology
    • /
    • v.29 no.3
    • /
    • pp.181-189
    • /
    • 1986
  • The present study was undertaken to investigate whether the known adenylate cyclase activators, forskolin and cholera toxin, would affect the germinal vesicle breakdown (GVBD) and the production of cAMP in mouse oocytes in vitro. To do this, in vitro oocyte culture method and adenylate cyclase assay were employed. In response to different concentrations of forskolin (20 to 80 $\\mu$g/ml) added to a culture medium, the percentage of GVBD significantly decreased (56 to 31%) in a dose-dependent manner as compared to that of control (63%). This inhibitory phenomenon by forskolin was reversible since the rate of GVBD was returned to the control level when the oocytes were transferred to a control medium following exposure to forskolin (80 $\\mu$g/ml). Treatment of cholera toxin (10 to 1, 000 ng/ml) was, however, ineffective in suppressing GVBD. When forskolin (10 to 80 $\\mu$g/ml) was added to the mouse oocyte extracts, cAMP production significantly increased by 5 to 18 fold, whereas cholera toxin (10 to 1, 000 ng/ml) was no longer effective. In addition, treatment of guanidyl-imidodiphosphate (GppNHp, 100 $\\mu$M), which is an activator of the regulatory unit of adenylate cycleas, with forskolin did not exhibit any changes in cAMP production as compared to that induced by forskolin alone. Neither cholera toxin nor cholera toxin plus GppNHp (100 $\\mu$M) exhibited any differences in mouse oocytes. From the above results, the suppression of GVBD by forskolin may be mediated by a high level of intracellular cAMP in mouse oocytes. It appears that the changes in intracellular cAMP level may an important role in the mouse oocyte maturation.

  • PDF

The Effect of Dohongsamul-tang on Cytokine Production in Peripheral Blood Monocular Cells of Patients with Acute Cerebral Infarction

  • Park, Sae-Wook;Lee, Sun-Woo;Kang, Baek-Gyu;Lee, In;Cho, Kwang-Ho;Moon, Byung-Soon
    • The Journal of Korean Medicine
    • /
    • v.27 no.4
    • /
    • pp.1-11
    • /
    • 2006
  • Objectives : We investigated the effect of Dohongsamul-tang (DHSMT) on the production of various cytokines in lipopolysaccaride (LPS) stimulated peripheral mononuclear cells (PBMCs) from CI patients. Methods: Cell viability was determined using MTT assay. ELISA was carried out for investigating $TNF-{\alpha}$, $IL-1{\beta}$, IL-6, IL-8, IL-4, and $TGF-{\beta}$ 1 Results : The amount of tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-$1{\beta}$, IL-6, IL-8, IL-4, and transforming growth factor(TGF)-${\beta}$ 1 in PBMC culture supernatant significantly increased in the LPS treated cells compared to unstimulated cells. We show that DHSMT inhibited the production of TNF-${\alpha}$, IL-1${\beta}$, IL-6, IL-8, and IL-4 induced by LPS in a dose dependent manner. The maximal inhibition rate of the TNF-${\alpha}$, IL-1${\beta}$, IL-6, IL-8, and IL-4 production by pretreatment of DHSMT (1.0mg/ml) was 38.52 ${\pm}$ 2.5% (P < 0.01), 44.02 ${\pm}$ 3.5% (P < 0.05), 45.32 ${\pm}$ 2.3% (P < 0.01), 42.30 ${\pm}$ 3.1% (P < 0.05), and 49.70 ${\pm}$ 3.1%(P &lt; 0.05), respectively. On the other hand, DMSMT significantly increased the LPS-induced TGF-${\beta}$ 1 production(P<0.05). Conclusions : Taken together. these results suggest that DHSMT might have regulatory effects on cytokine production, which might explain its beneficial effect in the treatment of CI.

  • PDF

The Effect of Dodamtang(DDT) on Brain damage and Hypertension (도담탕(導痰湯)이 뇌손상(腦損傷) 및 고혈압(高血壓)에 미치는 영향(影響))

  • Lim, Seong-Min;An, Joung-Jo;Choi, Young;Kim, Yong-Jin;Yoo, Ho-Ryoung;Park, Yang-Chun;Seol, In-Chan;Hwang, Chi-Won;Cho, Hyun-Kyung
    • The Journal of Internal Korean Medicine
    • /
    • v.22 no.4
    • /
    • pp.503-512
    • /
    • 2001
  • Objective : This study was carried out to investigate the effects of DDT on the brain damage and hypertension. Methods : We observed the effect of Dodamtang(DDT) extract on KCN-induced coma, focal brain ischemia by MCA occlusion, cytotoxicity and protection of PC12 cells and B103 cells induced by amyloid ${\beta}$ protein(25-35). To prove the effect of DDT as a blood pressure depressant, we measured aldosterone, renin activity, catecholamine, sodium and NO density using the seperated blood plasma. Results : DDT showed a protective effect on cytotoxicity of PC12 cells and B103 cells induced by amyloid ${\beta}$ protein(25-35) in a dose dependent manner and proved the significant abridgement of brain ischemic area and edema induced by MCA occlusion, a critical decrease of neurologic deficitic grade in the fore-limbs. DDT didn't reduce the duration of KCN(1.87mg/kg iv.)-induced coma and prolonged the survival rate in the case of KCN(3.0mg/kg iv.)-induced coma by the ratio of 20%. While DDT increased the value of NO in SHR, it significantly decreased the blood pressure of SHR and the value of aldosterone& epinephrine in SHR. Conclusions : These results suggested that DDT might be usefully applied for treatment of hypertension, cerebral infarction, and brain damage.

  • PDF

Effects of NaCl Concentration on the Growth of Native Willow Species Collected in a Coastal Reclaimed Land (간척지 자생 버드나무의 NaCl 농도별 생육반응)

  • Yeo, Jin-Kie;Park, Jung-Hyun;Koo, Yeong-Bon;Kim, Hyun-Chul;Shin, Han-Na
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.43 no.2
    • /
    • pp.124-131
    • /
    • 2010
  • This study was conducted to investigate the potentials for the forest restoration on reclaimed land by using willow trees (Salix koreensis Anderson) selected from a coastal reclaimed land made in inside of the Sihwa tide embankment. We first collected six individual willow trees that were the only tree species grown in the reclaimed land. Total 7 clones from cuttings of the collected trees and the control were grown in a greenhouse for two months prior to applying the different concentrations of NaCl solutions (0.0%, 0.1%, 0.5%, and 1.0%). One month after the NaCl application, the survival rates of clones from both the collected trees, and the control were significantly decreased in a NaCl dose-dependent manner. However, there was no significant difference between the collected trees and the control in terms of survival rate, hight and diameter of cuttings, and the numbers of leaves in greenhouse condition. In conclusion, the willow trees collected from the coastal reclaimed land showed no tolerance against NaCl compared to the control grown in ordinary soil, suggesting that further study is required to determine what the most important factor is to select salt tolerant tree species.

A Carbohydrate Fraction, AIP1, from Artemisia Iwayomogi Reduces the Action Potential Duration by Activation of Rapidly Activating Delayed Rectifier $K^+$ Channels in Rabbit Ventricular Myocytes

  • Park, Won-Sun;Son, Youn-Kyoung;Ko, Eun-A;Choi, Seong-Woo;Kim, Na-Ri;Choi, Tae-Hoon;Youn, Hyun-Joo;Jo, Su-Hyun;Hong, Da-Hye;Han, Jin
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.14 no.3
    • /
    • pp.119-125
    • /
    • 2010
  • We investigated the effects of a hot-water extract of Artemisia iwayomogi, a plant belonging to family Compositae, on cardiac ventricular delayed rectifier $K^+$ current ($I_K$) using the patch clamp technique. The carbohydrate fraction AIP1 dose-dependently increased the heart rate with an apparent $EC_{50}$ value of $56.1{\pm}5.5\;{\mu}g/ml$. Application of AIP1 reduced the action potential duration (APD) in concentration-dependent fashion by activating $I_K$ without significantly altering the resting membrane potential ($IC_{50}$ value of $APD_{50}$: $54.80{\pm}2.24$, $IC_{50}$ value of $APD_{90}$: $57.45{\pm}3.47\;{\mu}g/ml$). Based on the results, all experiments were performed with $50\;{\mu}g/ml$ of AIP1. Pre-treatment with the rapidly activating delayed rectifier $K^+$ current ($I_{Kr}$) inhibitor, E-4031 prolonged APD. However, additional application of AIP1 did not reduce APD. The inhibition of slowly activating delayed rectifier $K^+$ current ($I_{Ks}$) by chromanol 293B did not change the effect of AIP1. AIP1 did not significantly affect coronary arterial tone or ion channels, even at the highest concentration of AIP1. In summary, AIP1 reduces APD by activating $I_{Kr}$ but not $I_{Ks}$. These results suggest that the natural product AIP1 may provide an adjunctive therapy of long QT syndrome.

Effect of EGCG on Expression of Neurogenin 3 via the MAP Kinase Signaling Pathway in AR42J Cells, a Rat Pancreatic Tumor Cell Line (녹차 카테킨, Epigallocathechin Gallate (EGCG)의 흰쥐췌장종양 선 세포 AR42J의 MAP Kinase 세포 신호전달 기전을 통한 Neurogenin 3 발현에 미치는 영향)

  • Kim, Sung-Ok;Choe, Won-Kyung
    • Journal of Nutrition and Health
    • /
    • v.44 no.3
    • /
    • pp.196-202
    • /
    • 2011
  • Epigallocatechin gallate (EGCG), or epigallocatechin 3-gallate, is the ester of epigallocatechin and gallic acid, and is a type of catechin. EGCG may be therapeutic for many disorders including diabetics and some types of cancer. However it is unknown whether EGCG can induce transdifferentiation of pancreatic cells in pancreatitis. The aim of this study was to investigate the effects of EGCG on the expression of pancreatic regenerating related markers in pancreatic AR42J cells, a model of pancreatic progenitor cells. AR42J cells, differentiated with betacellulin and activin A, were cultured with/without EGCG in a time-dependent manner. Cell growth rate, levels of mRNA, and protein expression were examined with the MTT assay, quantitative PCR, and Western blots, respectively. The results showed that AR42J cell growth rates were inhibited by EGCG in a dose-dependent manner. mRNA and protein expression of amylase, insulin and neurogenin 3 (ngn 3) increased in AR42J cells treated with EGCG. Additionally, we demonstrated that the signal transduction pathway of mitogen-activated protein (MAP) kinase is active in EGCG-treated AR42J cells. ERK and JNK phosphorylation decreased in cells treated with EGCG but not p38 phosphorylation. Activation of the p38 MAP kinase pathway was confirmed by specific MAP kinase pathways inhibitors: U0126 for ERK, SP600126 for JNK, and SB203580 for p38. Activated p38 phosphorylation was inhibited by the specific p38 inhibitor SB203580 but p38 phosphorylation was inhibited with increased EGCG treatment. The ERK and JNK MAP kinase pathways were not affected by EGCG treatment. Although further studies are needed, these results suggest that EGCG affects the induction of pancreatic cell regeneration by increasing the ngn 3 protein and mRNA expression and activating the p38 MAP kinase pathway.

Nutrient intake, digestibility and performance of Gaddi kids supplemented with tea seed or tea seed saponin extract

  • Kumar, M.;Kannan, A.;Bhar, R.;Gulati, A.;Gaurav, A.;Sharma, V.K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.30 no.4
    • /
    • pp.486-494
    • /
    • 2017
  • Objective: An experiment was conducted to determine the nutrient intake, digestibility, microbial protein synthesis, haemato-biochemical attributes, immune response and growth performance of Gaddi kids fed with oat fodder based basal diet supplemented with either tea seed or tea seed saponin (TSS) extract. Methods: Eighteen male kids, $7.03{\pm}0.16$ months of age and $19.72{\pm}0.64kg$ body weight, were distributed into three groups, $T_0$ (control), $T_1$, and $T_2$, consisting of 6 animals each in a completely randomized design. The kids were fed a basal diet consisting of concentrate mixture and oat fodder (50:50). Animals in group III ($T_2$) were supplemented with TSS at 0.4% of dry matter intake (DMI), and group II ($T_1$) were supplemented with tea seed at 2.6% of DMI to provide equivalent dose of TSS as in $T_2$. Two metabolism trials were conducted, 1st after 21 days and 2nd after 90 days of feeding to evaluate the short term and long term effects of supplementation. Results: The tea seed ($T_1$) or TSS ($T_2$) supplementation did not affect DMI as well as the digestibility of dry matter, organic matter, crude protein, neutral detergent fibre, and acid detergent fibre. Nutritive value of diet and plane of nutrition were also comparable for both the periods. However, the average daily gain and feed conversion ratio (FCR) were improved (p<0.05) for $T_1$ and $T_2$ as compared to $T_0$. The microbial protein supply was also higher (p<0.05) for $T_1$ and $T_2$ for both the periods. There was no effect of supplementation on most blood parameters. However, the triglyceride and low density lipoprotein cholesterol levels decreased (p<0.05) and high density lipoprotein-cholesterol level increased (p<0.05) in $T_2$ as compared with $T_0$ and $T_1$. Supplementation also did not affect the cell mediated and humoral immune response in goats. Conclusion: Tea seed at 2.6% of DMI and TSS at 0.4% DMI can be fed to Gaddi goats to improve growth rate, FCR and microbial protein synthesis.