• Title/Summary/Keyword: pertussis

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Effects of Insulin and IGFs on Phosphate Uptake in Primary Cultured Rabbit Renal Proximal Tubule Cells

  • Han, Ho-Jae;Park, Kwon-Moo
    • The Korean Journal of Physiology
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    • 제30권1호
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    • pp.63-76
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    • 1996
  • The aim of present study was to characterize phosphate uptake and to investigate the mechanism for the insulin and insulin-like growth factor(IGF) stimulation of phosphate uptake in primary cultured rabbit renal proximal tubule cells. Results were as follows : 1. The primary cultured proximal tubule cells had accumulated $6.68{\pm}0.70$ nmole phosphate/mg protein in the presence of 140 mM NaCl and $2.07{\pm}0.17$ nmole phosphate/mg protein in the presence of 140 mM KCl during a 60 minute uptake period. Raising the concentration of extracellular phosphate to 100 mM$(48.33{\pm}1.76\;pmole/mg\;protein/min)$ induced decrease in phosphate uptake compared with that in control cells maintained in 1 mM phosphate$(190.66{\pm}13.01\;pmole/mg\;protein/min)$. Optimal phosphate uptake was observed at pH 6.5 in the presence of 140 mM NaCl. Phosphate uptake at pH 7.2 and pH 7.9 decreased to $83.06{\pm}5.75%\;and\;74.61{\pm}3.29%$ of that of pH 6.5, respectively. 2. Phosphate uptake was inhibited by iodoacetic acid(IAA) or valinomycin treatment $(62.41{\pm}4.40%\;and\;12.80{\pm}1.64%\;of\;that\;of\;control,\;respectively)$. When IAA and valinomycin were added together, phosphate uptake was inhibited to $8.04{\pm}0.61%$ of that of control. Phosphate uptake by the primary proximal tubule cells was significantly reduced by ouabain treatment$(80.27{\pm}6.96%\;of\;that\;of\;control)$. Inhibition of protein and/or RNA synthesis by either cycloheximide or actinomycin D markedly attenuated phosphate uptake. 3. Extracellular CAMP and phorbol 12-myristate 13 acetate(PMA) decreased phosphate uptake in a dose-dependent manner in all experimental conditions. Treatment of cells with pertussis toxin or cholera toxin inhibited phosphate uptake. cAMP concentration between $10^{-6}\;M\;and\;10^{-4}\;M$ significantly inhibited phosphate uptake. Phosphate uptake was blocked to about 25% of that of control at 100 ng/ml PMA. 3-Isobutyl-1-methyl-xanthine(IBMX) inhibited phosphate uptake. However, in the presence of IBMX, the inhibitory effect of exogenous cAMP was not significantly potentiated. Forskolin decreased phosphate transport. Acetylsalicylic acid did not inhibit phosphate uptake. The 1,2-dioctanoyl-sn-glycorol(DAG) and 1-oleoyl-2-acetyl-sn- glycerol(OAG) showed a inhibitory effect. However, staurosporine had no effect on phosphate uptake. When PMA and staurosporine were treated together, inhibition of phosphate uptake was not observed. In conclusion, phosphate uptake is stimulated by high sodium and low phosphate and pH 6.5 in the culture medium. Membrane potential and intracellular energy levels are also an important factor fer phosphate transport. Insulin and IGF-I stimulate phosphate uptake through a mechanisms that involve do novo protein and/or RNA synthesis and decrease of intracellular cAMP level. Also protein kinase C(PKC) is may play a regulatory role in transducing the insulin and IGF-I signal for phosphate transport in primary cultured proximal tubule cells.

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Sphingosine 1-Phosphate-induced Signal Transduction in Cat Esophagus Smooth Muscle Cells

  • Song, Hyun Ju;Choi, Tai Sik;Chung, Fa Yong;Park, Sun Young;Ryu, Jung Soo;Woo, Jae Gwang;Min, Young Sil;Shin, Chang Yell;Sohn, Uy Dong
    • Molecules and Cells
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    • 제21권1호
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    • pp.42-51
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    • 2006
  • We investigated the mechanism of contraction induced by S1P in esophageal smooth muscle cells. Western blot analysis demonstrated that $S1P_1$, $S1P_2$, $S1P_3$, and $S1P_5$ receptors existed in the cat esophagus. Only penetration of EDG-5 ($S1P_2$) antibody into permeabilized cells inhibited S1P-induced contraction. Pertussis toxin (PTX) also inhibited contraction, suggesting that it was mediated by $S1P_2$ receptors coupled to a PTXsensitive $G_i$ protein. Specific antibodies to $G_{i2}$, $G_q$ and $G_{\beta}$ inhibited contraction, implying that the S1P-induced contraction depends on PTX-insensitive $G_q$ and $G_{\beta}$ dimers as well as the PTX-sensitive $G_{i2}$. Contraction was not affected by the phospholipase $A_2$ inhibitor DEDA, or the PLD inhibitor ${\rho}$-chloromercuribenzoate, but it was abolished by the PLC inhibitor U73122. Incubation of permeabilized cells with $PLC{\beta}3$ antibody also inhibited contraction. Contraction involved the activation of a PKC pathway since it was affected by GF109203X and chelerythrine. Since $PKC{\varepsilon}$ antibody inhibited contraction, $PKC{\varepsilon}$ may be required. Preincubation of the muscle cells with the MEK inhibitor PD98059 blocked S1P-induced contraction, but the p38 MAP kinase inhibitor SB202190 did not. In addition, co-treatment of cells with GF 109203X and PD98059 did not have a synergistic effect, suggesting that these two kinases are involved in the same signaling pathway. Our data suggest that S1P-induced contraction in esophageal smooth muscle cells is mediated by $S1P_2$ receptors coupled to PTX-sensitive $G_{i2}$ proteins, and PTX-insensitive $G_q$ and $G_{\beta}$ proteins, and that the resulting activation of the $PLC{\beta}3$ and $PKC{\varepsilon}$ pathway leads to activation of a p44/p42 MAPK pathway.

The Signal Transduciton of Ginsenosides, Active Ingredients of Panax ginseng, in Xenopus oocyte: A Model System for Ginseng Study

  • Nah Seung-Yeol;Lee Sang-Mok
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 2002년도 학술대회지
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    • pp.66-83
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    • 2002
  • Recently, we have provided evidence that ginsenosides, the active components of Panax ginseng, utilize pertussis toxin (PTX)-insensitive $G{\alpha}_{q/11}-phospholipase\;C-{\beta}3(PLC-{\beta}3)$ signal transduction pathway for the enhancement of $Ca^{2+}-activated\;Cl^{-}$ current in the Xenopus oocyte (British J. Pharmacol. 132, 641-647, 2001; JBC 276, 48797-48802, 2001). Other investigators have shown that stimulation of receptors linked to $G{\alpha}-PLC$ pathway inhibits the activity of G proteincoupled inwardly rectifying $K^+$ (GIRK) channel. In the present study, we sought to determine whether ginsenosides influenced the activity of GIRK 1 and GIRK 4 (GIRK 1/4) channels expressed in the Xenopus oocyte, and if so, the underlying signal transduction mechanism. In oocyte injected with GIRK 1/4 channel cRNAs, bath-applied ginsenosides inhibited high potassium (HK) solution-elicited GIRK current $(EC_{50}:4.9{\pm}4.3\;{\mu}g/ml).$ Pretreatment of the oocyte with PTX reduced the HK solution-elicited GIRK current by $49\%,$ but it did not alter the inhibitory ginsenoside effect on GIRK current. Prior intraoocyte injection of cRNA(s) coding $G{\alpha}_q,\;G{\alpha}_{11}\;or\;G{\alpha}_q/G{\alpha}_{11},\;but\;not\;G{\alpha}_{i2}\;or\;G{\alpha}_{oA}$ attenuated the inhibitory ginsenoside effect. Injection of cRNAs coding $G{\beta}_{1{\gamma}2}$ also attenuated the ginsenoside effect. Similarly, injection of the cRNAs coding regulators of G protein signaling 1, 2 and 4 (RGS1, RGS2 and RGS4), which interact with $G{\alpha}_i\;and/or\;G{\alpha}_{q/11}$ and stimulates the hydrolysis of GTP to GDP in active GTP-bound $G{\alpha}$ subunit, resulted in a significant reduction of ginsenoside effect on GIRK current. Preincubation of GIRK channel-expressing oocyte in PLC inhibitor (U73122) or protein kinase C (PKC) inhibitor (staurosporine or chelerythrine) blocked the inhibitory ginsenoside effect on GIRK current. On the other hand, intraoocyte injection of BAPTA, a free $Ca^{2+}$ chelator, had no significant effect on the ginsenoside action. Taken together, these results suggest that ginsenosides inhibit the activity of GIRK 1/4 channel expressed in the Xenopus oocyte through a PTX-insensitive and $G{\alpha}_{q/11}$-,PLC-and PKC-mediated signal transduction pathway.

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예방접종과 관련된 소아 혈소판 감소 자반병의 임상적 특성 (Clinical features of vaccination-associated thrombocytopenic purpura in children)

  • 이완수;유승택;신새론;최두영
    • Clinical and Experimental Pediatrics
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    • 제51권6호
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    • pp.610-615
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    • 2008
  • 목 적 : 소아 특발성 혈소판 감소 자반병은 대부분 바이러스 감염 후 수주 후에 발병하나 약 7%에서는 홍역, 풍진, B형 간염, 독감, 수두, DTP등의 예방 접종과 관련되어 발생함이 보고 되었다. 본 연구는 예방접종과 관련된 혈소판 감소 자반병의 빈도와 임상적 특성을 알아보고 예방접종과 관련이 없는 혈소판 감소 자반병과의 차이점을 분석하고자 하였다. 방 법 : 1994년 1월부터 2007년 7월까지 원광대학교 병원 소아과에 혈소판 감소 자반병으로 입원한 환아 105명을 대상으로 의무기록지를 이용하여 후향적으로 조사하였다. 예방접종과 관련된 혈소판 감소 자반병은 예방 접종 후 1개월 이내 발병으로 정의하였으며 예방접종관련 군과 없는 군으로 분류하여 여러 임상적 특성에 대해비교 분석하였다. 결 과 : 혈소판 감소 자반병은 총 105례였으며 이중 13례(12.4 %)가 예방접종과 관련되었고 DTP에 의한 경우가 8례로 가장 많았으며 HBV가 2례, 인플루엔자, MMR, 일본뇌염이 각각 1례였다. 예방접종과 관련된 군에서 다음 예방접종 시 혈소판 감소 자반병이 재발한 예는 없었다. 예방 접종 군에서 관련이 없는 군에 비해 진단 시 연령이 의미 있게 낮았으며 빈혈이 더 많이 동반되었으며 합병증과 관련이 있는 혈소판 $20{\times}10^9/L$ 미만의 위험기간이 짧았다. 또한 예방 접종 군에서 구강내 출혈, 혈변, 혈뇨와 비출혈과 같은 심한 증상이 적고 1개월 내 관해가 높았으나 통계학적 차이는 없었다. 결 론 : 예방접종과 관련된 혈소판 감소 자반병이 관련이 없는 경우에 비해 증상이 경미하고 양성의 경과를 보였으며 다음 예방 접종은 주의하여 정상적인 스케줄에 따라 시행하며 예방접종 후 혈소판 검사를 반드시 시행할 필요는 없을 것으로 사료된다.

전라북도 아동의 예방접종실태에 관한 조사연구 (Study on Vaccination State in Children : Jeonbuk Province, 2000)

  • 정주미;김정철;은소희;황평한;;;김정수
    • Clinical and Experimental Pediatrics
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    • 제45권10호
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    • pp.1234-1240
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    • 2002
  • 목 적: 전라북도지역의 어린이 예방접종의 실태를 파악함으로써 문제점을 알아보고 예방접종률과 접종 시기의 적절성을 향상시키고자 하였다. 방 법: 2000년 3월부터 6월까지 전북지역의 5세 이하의 소아 850명을 대상으로 하였으며 조사방법은 보호자의 면담과 예방접종수첩 등 의무기록을 근거로 이루어 졌다. 예방접종 종류에 따른 접종여부, 접종시기와 횟수, 접종장소에 대해 조사하였다. 결 과 : 1) 조사방법은 전체 850명 중 362명(43%)은 예방접종수첩을 통해 이루어졌으며, 488명(57%)은 보호자의 기억을 통한 면담으로 이루어졌다. 2) 전체 예방접종의 50.4%는 보건소에서, 44.3%는 개인의원에서, 5.3%는 대학병원과 종합병원에서 이루어졌다. 기본접종인 BCG(49%), B형 간염(47%), DTaP(61%), MMR(55%), 일본뇌염(73%)은 보건소에서 주로 접종되었고, 수두(62%)와 Hib백신(88%)등 선별접종은 개인의원에서 더 많이 이루어졌다. 3) 예방접종률은 BCG는 99.2%, B형 간염은 93.5%, DTaP & TOPV는 96.1%로 비교적 접종률이 높았으나, 선별접종인 MMR은 83.7%, 수두는 72.5%, 일본뇌염은 50.2%, Hib는 15.8%로 낮은 접종률을 보였다. 4) 예방접종 시기의 적절성은 B형간염은 88.4%, DTaP는 72.8%, 일본뇌염은 18.5%로 각각의 접종률인 93.5%, 94.6%, 50.2%와 큰 차이를 보였다. 결 론 : 1세 미만에 실시하는 예방접종들의 접종률은 비교적 높았으나 1세 이후에 실시하거나, 여러 차례 추가접종이 필요한 경우는 접종률과 적절성이 모두 낮았다. 특히, MMR, 수두, 일본뇌염, Hib 백신의 경우 지역사회에서의 유행을 예방하기에는 아직 낮은 수준으로 평가된다. 이러한 예방접종률을 높이기 위해서는 무엇보다도 부모들의 백신 접종에 대한 인식을 높이는 것이 중요하고, 예방접종기록을 표준화하고 전산화하며, 예방접종 기록을 초등학교 입학시에 제출하는 것을 의무화하는 것이 바람직할 것이다. 그리고, 예방접종 사업에 대한 평가와 이를 환류 할 수 있는 감시체계가 필요할 것으로 생각된다.