• The Korean Journal of Physiology and Pharmacology
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• 제1권5호
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• pp.495-504
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• 1997

Water transport is mediated by two distinct pathways, diffusional and channel-mediated water transport. The first molecular water channel was identified from human erythrocytes in 1992. Genetically-related proteins from other mammalian tissues have subsequently been identified to transport water, and the group is referred to as th "Aquaporins". Aquaporin-4 (AQP4) is most abundant in the brain, which may be involved in CSF reabsorption and osmoregulation. However, ontogeny and regulatory mechanisms of AQP4 channels have not been reported. Northern blot analysis showed that AQP4 mRNA began to be expressed in the brain just before birth and that its expression gradually increased by PN7 and then decreased at adult level. AQP4 was expressed predominantly in the ependymal cells of ventricles in newborn rats. And then its expression decreased in ependymal cells and increased gradually in other regions including supraoptic and paraventricular nuclei. AQP4 is also expressed in the subfornical organ, in which the expression level is not changed after birth. Cryogenic brain injury did not affect expression of AQP4 mRNA, while ischemic brain injury decreased it. Osmotic water permeability of AQP4 channel expressed in Xenopus oocytes was inhibited by the pretreatment of BAPTA/AM and calmidazolium, a $Ca^{2+}/Calmodulin$ kinase inhibitor, in a dose-dependent manner. These results indicate that the expression and the function of AQP4 channel are regulated by developmental processes and various pathophysiological conditions. These results will contribute to the understanding of fluid balance in the central nervous system and the osmoregulatory mechanisms of the body.

• 약학회지
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• 제40권4호
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• pp.468-477
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• 1996

Vasopressin which is an antidiuretic hormone in human body produced the diuretic action in dog. This study was investigated in order to certify the diuretic action and to search out the mechanism of the action on the vasopressin. Vasopressin, when given in a dose of 10.0mU/kg, bolus+1.0mU/kg/min intravenously, exhibited the increase of urine flow(Vol), renal plasma flow(RPF), osmolar clearance (Cosm) and amounts of sodium and potassium excreted in urine ($E_{Na},\;E_K$), the decrease of reabsorption rate of sodium and potassium in renal tubules ($R_{Na},\;R_K$), and then elevated the mean arterial pressure(MAP). Vasopressin given in a increased dose to 30.0mU/kg, bolus+1.0mU/kg/min intravenously elicited the same aspect with that exhibited by a small dose in changes of Vol. and all renal function and potentiated the change rates, whereas this time MAP did not change at all when compared with control value. Vasopressin, when administered into a renal artery, did not induce the changes of Vol and all renal function in experimental (administered) kidney, but increased slightly the Vol, glomerular filtration rate(GFR), $E_{Na},\;and\;E_K$ expected the no change of $R_{Na}\;and\;R_K$ in the control (not administered) kidney. Vasopressin, when infused into carotid artery, showed the increase of Vol. GFR, $E_{Na},\;and\;E_K$ and no change of $R_{Na}\;and\;R_K$ in a dose of 1/5 of intravenous dose. Diuretic action of vasopressin administered into carotid artery was not influenced by renal denervation. Above results suggest that vasopressin produced diuretic action by hemodynamic changes in dogs. These hemodynamic changes may be mediated by central endogenous substances not associated with renal nerve.

• 대한방사선기술학회지:방사선기술과학
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• 제32권2호
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• pp.213-218
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• 2009

감마선 원천핵을 두 개의 금속 평행판 사이, 실린더나 구와 같은 유한한 공간 내부에 놓았을 때 에너지 준위폭이 어떻게 변경되는가에 대하여 이론적으로 조사했다. 2개의 금속판에 의해 뒤쪽 산란된 감마선이 원천핵에 재흡수됨으로써 $^{133}Cs$핵의 여기상태(81 keV)의 에너지폭은 평행판 간격이 1.0 mm일 때 4.2 K에서 3.7% 정도 감소됨을 볼 수 있었다. 여기서 금속판은 두께 0,5 mm, 반경이 3 cm이며 금으로 만들었다. 반경 1.0 mm, 두께 0.5 mm, 길이 5 cm의 실린더 금판에 의해 뒤쪽 산란되었을 때에는 4.2 K에서 6.5% 에너지 폭이 좁아지는 결과를 얻었다. 또한, 두께 0.5 mm, 반경 1.0 mm의 금으로 된 구 안에 원천핵을 놓았을 때 4.2 K에서 18.2% 에너지준위 폭이 감소하였다. 이러한 에너지 준위 폭의 감소는 그 준위의 반감기가 연장된 것을 의미한다.

• 대한소아치과학회지
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• 제32권1호
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• pp.152-157
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• 2005

Hypophosphatemia rickets는 비타민 D의 치료량에 내성을 갖기 때문에 Vitamin D-resistant rickets(VDRR)라고도 명명되며, 이는 요세관으로부터 무기질 인산의 재흡수가 감소됨으로써 혈청 칼슘농도는 정상이나 인산농도가 낮고 alkaline phosphatase가 약간 증가되기 때문에 쉽게 진단되는 구루병의 한 형태이다. 이러한 Hypophosphatemia rickets의 임상적인 소견으로 양다리가 휘는 것. 작은 키, 척추측만. 손목과 발목부위의 팽대가 나타나며 구강내 소견으로는 자발적인 치성농양의 높은 발생률, 맹출 지연, 근단공의 폐쇄지연, 얇고 저형성된 법랑질, 명확히 인지하기 힘든 치조백선, 확대된 치수강, 법랑상아경계까지 연장된 치수각 등이 있다. 본 증례는 유치의 상실과 그에 따른 치료를 위해 본원 소아과에서 의뢰된 비타민 D저항성 구루병 환아의 임상소견과 그 치과적 치료에 대해 보고하는 바이다.

• Archives of Plastic Surgery
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• 제39권6호
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• pp.659-662
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• 2012

Progressive facial hemiatrophy, also known as Parry-Romberg syndrome, is a progressive and self-limited deformation of the subcutaneous tissue volume on one side of the face that creates craniofacial asymmetry. We present the case of a patient with a five-year history of progressive right facial hemiatrophy, who underwent facial volumetric restoration using cell-assisted lipotransfer (CAL), which consists of an autologous fat graft enriched with adipose-derived stem cells (ASCs) extracted from the same patient. ASCs have the capacity to differentiate into adipocytes. They also promote angiogenesis, release angiogenic growth factors, and some can survive as stem cells. The use of autologous fat as a filler in soft tissue atrophy has been satisfactory in patients with mild and moderate Parry-Romberg syndrome. Currently, CAL has showed promising results in the long term by decreasing the rate of fat reabsorption. The permanence and stability of the graft in all the injected areas has showed that autologous fat grafts enriched with stem cells could be a promising technique for the correction of defects caused by this syndrome.

• 한국세라믹학회지
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• 제37권2호
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• pp.111-116
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• 2000

700nm red emission(3F3longrightarrow3H6) in Tm3+ ion with 800 nm(3H6longrightarrow3H4) excitation via upconversion process has been reported only in host materials which have low phonon energies such as halide crystals. However, we observed 700nm and 480nm(1G4longrightarrow3H6) upconverted emission with 800nm excitation in several oxide glasses which has never reported. With spectroscopic analyses and lifetime measurements of each nergy level of Tm3+ ion doped in various oxide glasses, following mechanisms are suggested. For red upconversion, upconversion mechanism changed with Tm3+ concentration. While direct excitation up to 3F3 level via anti-Stokes excitation was dominated at low concentration, two-step excitation via 3H6longrightarrow3H4 and 3F4longrightarrow3F3 transitions was dominated at high concentration. For blue upconversion, two step excitation mechanism up to 1G4 level was suggested as follows : electrons are exciated up to 3H5 with direct excitation with pumping light up to 3H4 followed by multiphonon relaxation, and then additional reabsorption of pumping light excites electrons up to 1G4.

• Asian-Australasian Journal of Animal Sciences
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• 제10권3호
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• pp.260-264
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• 1997

This study was conducted with adult cockerels to determine whether dietary RNA affects feed intake and renal weight and function, and if the responses are similar to dietary adenine. Chickens were ad libitum fed a RNA diet (100 g/kg) or an adenine diet (9.1 g/kg) for 14 d and catheterized in right jugular vein, hepatic portal vein and both urethers, and saline together with para-amino hippuric acid and sodium thiosulfate was continuously infused into them to evaluate renal functions. Dietary RNA reduced feed intake and body weight, and dietary adenine increased kidney weight expressed as a proportion of body weight (P < 0.05). Feed intake and body weight on the adenine diet and kidney weight on the RNA diet showed similar though non significant tendencies. No calculi were detected in the kidney in chickens fed either the RNA or adenine diets. Plasma inorganic phosphate (IP), Ca and 1,25 $(OH)_2$ vitamin $D_3$ concentrations were increased by dietary RNA and adenine, although the increases of IP and Ca in adenine-fed chickens were not significant. Uric acid and urea concentrations in the blood plasma were unaffected by dietary RNA or adenine. Both dietary RNA and adenine increased renal blood flow rates 3.5-3.7 fold, renal plasma flow rates 3.4-3.7 fold and glomerular filtration rates (GFR) 2.9-3.0 fold (p < 0.01). Clearance of urea, IP and Ca were also enhanced by dietary RNA, but not by dietary adenine. However, neither RNA nor adenine affected uric acid clearance. Only IP clearance was significantly augmented at the glomerular level by dietary RNA (p < 0.05). Glomerular filtration of uric acid, urea, IP and Ca and reabsorption of urea, IP and Ca at the renal tubule were increased by dietary RNA and adenine (p < 0.05), whereas tubular secretion of uric acid was decreased by both dietary treatments. It is concluded that dietary adenine is effective in changing renal function and P and Ca metabolism in chickens.

• 대한한의학회지
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• 제22권3호
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• pp.21-30
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• 2001

목적 : 이전 연구에서 단삼 추출액이 강력한 항산화 작용이 있음을 확인한 바 있어 단삼 추출액이 신장세뇨관 세포에서 oxidant에 의한 세포사망 및 DNA 손상을 방지하는 지를 조사하고 이러한 효과가 지질의 과산화를 억제하는 효과에 기인하는 지를 시험하였다. 방법 : 신장 근위세뇨관 세포 유래 세포주인 opossum kidney (OK)세포를 이용하여 세포 사망은 frypan blue exclusion방법을 이용하여 평가하였고, DNA손상 정도는 double stranded DNA의 파괴를 측정하여 평가하였다. Oxidant 약물 모델로는 $H_2O_2$를 사용하였다. 결과 : $H_2O_2$는 적용시 간과 농도에 비례하여 세포 사망을 유도하였다. 단삼 추출액은 0.05% 농도에서 $H_2O_2$에 의한 세포사망 및 DNA 손상을 방지하였다. 이러한 방지효과는 $H_2O_2$ 제거 효소인 catalase와 철 착염제인 deferoxamine에 의해서도 나타났다. 그러나 강력한 항산화제인 DPPD는 $H_2O_2$에 의한 세포 사망이나 DNA손상을 방지하지 못하였다. $H_2O_2$는 세포내 ATP 농도를 감소시켰으며. 이러한 감소는 poly (ADP-ribose) polymerase억제제인 3-aminobenzamide에 의해 방지되었으나 단삼 추출액에 의해서는 영향을 받지 않았다. 3-aminobenzamide는 $H_2O_2$에 의한 세포 사망을 방지하였다. $H_2O_2$는 지질의 과산화를 증가시켰으며, 이러한 변화는 단삼 추출액과 DPPD에 의해 방지되었다 결론 : OK 세포에서 $H_2O_2$에 의한 세포사망과 DNA 손상에는 지질의 과산화가 중요한 역할을 하지 않으며, 단삼 추출액의 $H_2O_2$에 의한 세포 사망과 DNA 손상 방지 효과는 항산화 작용이 아닌 다른 기전에 기인하는 것으로 사료된다.

• 대한한의학방제학회지
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• 제17권2호
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• pp.187-194
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• 2009

The kidney toxicities of WK-38 used for improvement of the vascular diseases, was examined using male and female Sprague-Dawley rats. The male and female rats were divided into 4 groups for intragastrical treatment with doses of 0, 5, 50, and 500 mg/kg/day for 13 weeks, respectively. In all male and female rats treated with WK-38, no mortality and gross pathological findings were shown for 13 weeks. There was substantially no change in body weight in all rats with treatment of WK-38. Urine osmolality as renal functional parameters were not exchanged in all rats treated with WK-38. The renal functional parameters including electrolytes excretory rate, creatinine clearance, and solute-free water reabsorption were significantly augmented on account of increase in urinary volume in female rats treated with WK-38, but not male. In summary, this study demonstrates that WK-38 exhibits no toxicity on kidney in all male and female rats.

• The Korean Journal of Physiology
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• 제25권1호
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• pp.37-48
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• 1991

The characteristics of probenecid effect on renal urate excretion in the cat were studied by clearance method and compared with those in the rabbit. In the cat GFR was $3.03{\pm}0.09\;ml/min{\cdot}kg$, and endogenous plasma urate concentration was $1.12{\pm}0.57\;{\mu}g/ml$, which is less than that in the rabbit $(3.33{\pm}0.46\;{\mu}g/ml)$. In the rabbit, $FE_{ur}$ was $1.76{\pm}0.08$ and net urate secretion was observed, while, in the cat $FE_{ur}$ was $0.70{\pm}0.02$ and net reabsorption was observed. In the cat $FE_{ur}$ was dependent on urine flow and independent of plasma urate concentration. In the rabbit $FE_{ur}$ was suppressed by infusion of probenecid $(30\;mg/kg\;-0.6\;mg/kg{\cdot}min)$ into femoral vein. In the cat the same dose of probenecid increased $FE_{ur}$ and concomitantly increased urine flow. Thus, an increase in $FE_{ur}$ by probenecid could be considered to be resulted from a change in urine flow. In the cat infusion of probenecid $(2.5\;mg/kg{\cdot}min)$ into renal artery markedly suppressed $FE_{P\;A\;H}$, but the effects on $FE_{ur}$ and urine flow were similar to those when probenecid was infused into femoral vein. These results indicate that in the cat kidney urate filtered through glomerulus is reabsorbed by a probenecid-insensitive mechanism with no evidence for net secretion.