• Biomedical Science Letters
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• v.23 no.3
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• pp.194-200
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• 2017

Bone-resorbing osteoclasts play a major role in maintaining bone homeostasis with bone-forming osteoblasts. Although it has been reported that A2B adenosine receptor (A2BAR) regulates osteoclast differentiation, its effects on apoptosis or proliferation of osteoclasts have been less-defined. Here, we demonstrate that A2BAR stimulation regulates macrophage-colony stimulating factor (M-CSF)-mediated osteoclast proliferation. Stimulation with a specific agonist of A2BAR, BAY 60-6583, significantly reduced M-CSF-mediated osteoclast proliferation in a time- and dose-dependent manner. In addition, A2BAR stimulation induced both apoptosis of the cells and cell arrest in the G1 phase with a decrease of cell number in the G2/M phase. Stimulation with BAY 60-6583 inhibited the activation of Akt by M-CSF, whereas M-CSF-induced ERK1/2 activation was not affected. These results suggest that the inhibition of M-CSF-mediated Akt activation by A2BAR stimulation increases apoptotic response of osteoclasts and induces cell cycle arrest in the G1 phase, thus contributing to the down-regulation of osteoclast proliferation.

• Journal of Pharmaceutical Investigation
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• v.25 no.3
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• pp.7-20
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• 1995

Taurine, a ${\beta}-amino$ acid, plays an important role as a neuromodulator and is necessary for the normal development of the brain. Since de novo synthesis of taurine in the brain is minimal and in vivo studies suggest that taurine dose not cross the blood-brain barrier, we examined whether the choroid plexus, the blood-cerebrospinal fluid (CSF) barrier, plays a role in taurine transport in the central nervous system. The uptake of $[^3H]-taurine$ into ATP depleted choroid plexus from rabbit was substantially greater in the presence of an inwardly directed $Na^+$ gradient taurine accumulation was negligible. A transient in side-negative potential gradient enhanced the $Na^+-driven$ uptake of taurine into the tissue slices, suggesting that the transport process is electrogenic, $Na^+-driven$ taurine uptake was saturable with an estimated $V_{max}$ of $111\;{\pm}\;20.2\;nmole/g/15\;min$ and a $K_M\;of\;99.8{\pm}29.9\;{\mu}M$. The estimated coupling ratio of $Na^+$ and taurine was $1.80\;{\pm}\;0.122.$ $Na^+-dependent$ taurine uptake was significantly inhibited by ${\beta}-amino$ acids, but not by ${\alpha}-amino$ acids, indicating that the transporter is selective for ${\beta}-amino$ acids. Since it is known that the physiological concentration of taurine in the CSF is lower than that in the plasma, the active transport system we characterized may face the brush border (i.e., CSF facing) side of the choroid plexus and actively transport taurine out of the CSF. Therefore, we examined in vivo elimination of taurine from the CSF in the rat to determine whether elimination kinetics of taurine from the CSF is consistent with the in vitro study. Using a stereotaxic device, cannulaes were placed into the lateral ventricle and the cisterna magna of the rat. Radio-labelled taurine and inulin (a marker of CSF flow) were injected into the lateral ventricle, and the concentrations of the labelled compounds in the CSF were monitored for upto 3 hrs in the cisterna magna. The apparent clearance of taurine from CSF was greater than the estimated CSF flow (p<0.005) indicating that there is a clearance process in addition to the CSF flow. Taurine distribution into the choroid plexus was at least 10 fold higher than that found in other brain areas (e. g., cerebellum, olfactory bulb and cortex). When unlabelled taurine was co-administered with radio-labelled taurine, the apparent clearance of taurine was reduced (p<0.0l), suggesting a saturable disposition of taurine from CSF. Distribution of taurine into the choroid plexus, cerebellum, olfactory bulb and cortex was similarly diminished, indicating that the saturable uptake of taurine into these tissues is responsible for the non-linear disposition. A pharmacokinetic model involving first order elimination and saturable distribution described these data adequately. The Michaelis-Menten rate constant estimated from in vivo elimination study is similar to that obtained in the in vitro uptake experiment. Collectively, our results demonstrate that taurine is transported in the choroid plexus via a $Na^+-dependent,saturable$ and apparently ${\beta}-amino$ acid selective mechanism. This process may be functionally relevant to taurine homeostasis in the brain.

• Clinical and Experimental Pediatrics
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• v.45 no.4
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• pp.439-448
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• 2002

Purpose : The aim of this study is to determine and compare the effects of adjunctive therapy with different doses of recombinant human granulocyte-colony stimulating factor(rhG-CSF) on reversing sepsis-associated neonatal neutropenia, and their survival rate in a group I/II-type trial. Methods : RhG-CSF was injected subcutaneously to 10 septic-neutropenic neonates with doses of $10{\mu}g/kg$ from Oct. 1995 to Sep. 1996, and was administered to another 12 septic-neutropenic neonates with doses of $5{\mu}g/kg$ from Oct. 1996 to Sep. 1997. Neutrophilic responses and the outcomes of both groups were compared. Results : In the rhG-CSF $10{\mu}g/kg$ treated group and in the $5{\mu}g/kg$ treated group, the absolute neutrophil count(ANC) was $1,065{\pm}89$($mean{\pm}SEM$) and $1,053{\pm}131$, respectively. The only difference between the two groups was the peak ANC at 48 hours. Eight patients from the remaining nine of rhG-CSF $10{\mu}g/kg$ treated group(88.9％) and ten in $5{\mu}g/kg$ treated group(83.3％) survived the sepsis and were discharged without any problems. Conclusions : RhG-CSF can increase the neutrophil count in critically ill septic neutropenic neonats. The survival rate of both groups were up to 90％. This finding suggests that both doses of rhG-CSF may be effective in a therapeutically useful time frame to treat septic neonates with neonatal neutropenia attributable to bone marrow supression or neutrophil consumption.

• Journal of Korean Neurosurgical Society
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• v.29 no.12
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• pp.1634-1641
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• 2000

Objective : The cerebrospinal fluid(CSF) pulsates within the craniospinal axis in response to rhythmic cerebral blood volume variation during the cardiac cycle. The aim of this study is to characterize the normal and abnormal CSF flow and its waveforms in the cervical spinal subarachnoid space. Methods : The magnetic resonance(MR) images were obtained with 1.5 T(GE Signa, GE Medical Systems, Milwaukee, USA) unit using the 2 dimensional cine PC(phase contrast) sequence with cardiac gating and gradient recalled echo imaging. This pulse sequence yielded 16 quantitative flow-encoded images per cardiac cycle. Sagittal and axial images of the cervical spinal CSF space were obtained, and target sites were analyzed for characteristic CSF flow (TR=50ms, TE=12.5-15ms). The region of interest(ROI) was 1mm 3 in volume. Twenty six persons were included in this study : 10 healthy volunteers and 16 patients with cervical myelopathy. The post-operative cine MR study were also done in five patients. Results : The normal CSF pulsation dynamics in the cervical spine showed discrete systolic and diastolic components. The CSF flow revealed a sine wave pattern, in which the systolic phase was shorter than the diastolic phase(ratio=2 : 3). The patient group revealed decreased amplitudes of the CSF flow and irregularly distored flow waves. The systolic phase was elongated in the ROI above the stenotic level, whereas the diastolic phase was lengthened below the level. In the postoperative images, the abnormal pattern and amplitude were found to be corrected. Conclusion : From these results, the authors believe that the CSF flow study provides valuable informations regarding the extent of cervical stenosis and may be useful for the surgical planning and post-operative evaluation.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.325-328
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• 2002

Production of human granulocyte-macrophage colony stimulating factor (hGM-CSF) by Nicotiana tabacum cell suspension culture was studied in Murashige and Skoog (MS) medium with sucrose as a carbon source, ammonium nitrate and potassium nitrate as nitrogen sources, potassium dihydrogen phosphate and sodium dihydrogen phosphate hydrate as phosphate sources, respectively. Optimum concentrations for carbon, nitrogen, phosphate was determined to enhance the production of hGM-CSF. Cell growth was better at high initial sucrose concentration (60 g/L), high initial nitrogen concentration (121.04 mM). Maximum cell density (18.28 g/L) was obtained at 60 g/L of sucrose after 14 days. Cell growth was not so good at low initial sucrose concentration 00 g/L), but the highest hGM-CSF production was obtained at the latter half of exponential phase. hGM-CSF production increased about 3 fold at initial phosphate concentration of 4.96 nM

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.321-326
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• 2000

To examine the feasibility of the long-term production of the human granulocyte colony stimulating factor (hG-CSF) using the $_{L}-arabinose$ promoter system of Escherichia coli, flask relay culture and cyclic fed-batch culture were performed. In the flask relay culture, it was found that the pismid was maintained stably up to about 170 generations in an uninduced condition, whereby the cells could also maintain the capability of expressing hG-CSF expression were maintained stably up to at least 100 generations. In contrast, in the cyclid fed-batch culture, segregational plasmid instability was observed within about 4 generations after induction, even though the cell growth and hG-CSF production reached their maximum balues, 78.0 g/l of dry cell weight and 7.0 g/l of hG-CSF, respectively. It would appear that, when compared to the flask relay culture, the high-cell density and high-level expression of hG-CSF in the cyclic fed-batch cultrure led to the segregational plasmid instability; in other words, a severe metabolic burden existe on the cells due to the high-level expression of hG-CSF. Accordingly, based on these long-term cultures, the segregational and structural plasmid instability was observed and a strategy to overcome such problems could be designed.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.289-292
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• 2003

Effects of immobilization on the production of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) by Nicotiana tabacum cells were investigated using alginate and polyurethane foam as immobilization matrices. Encapsulation of the cells in alginate decreased protein production by 50% compared with that of suspension culture. Maximum hGM-CSF concentration was obtained by the cells immobilizaed in polyurethane foam. High hGM-CSF production could be possible when polyurethane foam was used because of high specific production and easy immobilization for cell recycling process with high cell density.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.3
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• pp.187-191
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• 2003

Proteolytic enzymes existing in plant cell cultured media are the major reason for the loss of secreted human granulocyte-macrophage colony-stimulating factor (hGM-CSF). The addition of pepstatin, aprotinin and PMSF relatively decreased the proteolytic degradation of hGM-CSF in a conditioned medium, but sufficient prevention against the proteolytic activity could not be obtained with chemical protease inhibitors. Gelatin, as a competitive substrate for protease, showed a stabilizing effect in a conditioned medium. Compared to the initial hGM-CSF concentration in a conditioned medium. with 10 g/L of gelatin, 68% of the hGM-CSF remained after 5 days. In a cell culture experiment, 5 g/L of gelatin significantly stimulated the hGM-CSF production and accumulation in culture media, with no growth inhibition. compared to the controls (4.72 $\mu\textrm{g}$/L), the extracellular hGM-CSF level could be increased to 39.78 $\mu\textrm{g}$/L with the addition of 5 g/L of gelatin.

• Journal of Korean Neurosurgical Society
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• v.50 no.3
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• pp.274-276
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• 2011

Spontaneous cerebrospinal fluid (CSF) leak is a recognized cause of spontaneous intracranial hypotension (SIH). Subdural hematoma (SDH) is a serious but rare complication of SIH. An autologous epidural blood patch at the CSF-leak site can effectively relieve SIH. We report a case of bilateral SDH with SIH caused by a CSF leak originating at the C1-2 level. A 55-year-old male complained of orthostatic headache without neurological signs. His symptoms did not respond to conservative treatments including bed rest, hydration and analgesics. Magnetic resonance imaging showed a subdural hematoma in the bilateral fronto-parietal region, and computed tomography (CT) myelography showed a CSF leak originating at the C1-2 level. The patient underwent successful treatment with a CT-guided epidural blood patch at the CSF-leak site after trephination for bilateral SDH.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.95-95
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• 1993

대상환자는 15예로, 14예에서 평가가능하였다. 남녀비는 8:6, 중앙연령 32세(10-70세)이었고, 대상질환은 악성골육종 7예, 악성임파종 2예, 위암2예, 폐암 2예, 그리고 자궁악성육종 1예였다. CSF 50 ug/$m^2$ 3예, 100 ug/$m^2$ 3예,150 ug/$m^2$ 3예, 250 ug/$m^2$ 3예,350 ug/$m^2$ 3예, 500 ug/$m^2$ 6예, 700 ug/$m^2$ 용량 3예에서 시행되었다. 1주기 시행한 환자는 7예, 2주기 5예, 3주기, 4주기 각각 1예씩이었다. 부작용은 50-150ug/$m^2$에서 WHO grade I의 발열, 전신쇠약, 식욕부진 등이 관찰되었으나 grade II이상의 부작용은 없었다. 250 ug/$m^2$ 이상의 용량에서도 grade II의 발열이 관찰되었을 뿐 다른 중증의 부작용은 관찰되지 않았다. 최고용량인 700 ug/$m^2$ 에서도 grade II의 발열외의 중한 부작용은 관찰되지 않았다. 각 용량에 따른 백혈구 증가율(%투여제2일/투여제1일)은 130-500% 이었다. 시행된 약동태는 CSF 투여 2-4 시간 후 최고치 (0.42-15.4 ng/ml)를 나타내고 투여 12시간까지 0.2-2 ng/ml의 농도로 지속되었다. 소변내 CSF 배설량은 총투여량의 1% 미만이었다. CSF중화항체는 전예에서 검출되지 않았다.