• Archives of Pharmacal Research
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• v.16 no.3
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• pp.191-195
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• 1993

We investigated the effects of n-alkanols on the range and rate of the lateral diffusion of 1, 3-di(1-pyrenyl)propane in the model membranes of total phospholipid fraction extracted from synaptosomal plasma membrane vesicles. n-Akanols increased the range and rate of the lateral diffusion of 1, 3-di(1-pyrenyl)propane in the bulk model membrane structures (inner + outer monolayers) and the potencies of n-alknols up to 1-nonanol increased by 1 order of magnitude as the carbon chain length increases by two carbon atoms. The cut-off phenomenon was reached at 1-decanol, where further icnrease in hydrocarbon length resulted in a decrease in the lateral diffusion. However, significant changes in the 1'/1 value were not observed by methanol (from 100 to 2500 mM), ethanol (from 25 to 800 mM), and 1-propanol (from 10 to 250 mM) over entire concentration.

• Journal of Veterinary Clinics
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• v.36 no.6
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• pp.319-324
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• 2019

Receptor tyrosine kinases (RTK) are major promising targets in anticancer therapy in human and veterinary medicine. Using immunohistochemistry method, we evaluated the expressionof five types RTK (PDGFR-α, PDGFR-β, VEGFR 2, c-Kit and Abl) in the six canine brain tumor samples (2 meningioma, 2 astrocytoma, 1 ependymoma and 1 choroid plexus papilloma). A total of five samples expressed PDGFR-β (5/6), one sample, the choroid plexus papilloma, expressed c-Kit (1/6), and a total of two samples expressed Abl (2/6). None of the samples showed expression of PDGFR-α and VEGFR 2. We demonstrate that a significant portion of canine brain tumors express tyrosine receptors for growth factors and show that these receptors generally localize to tumor cell membranes and the cytoplasm. Evaluation of immunohistochemical expression for the RTKs PDGFR-β, c-Kit, and Alb in canine brain samples reveals an interesting potential for molecular targeting by TKIs in therapeutic studies of canine brain tumors, and more studies will be needed to assess the interactions and efficacy of these RTKs and TKIs. Based on these results, we have some evidence for novel chemotherapeutic trials using TKIs for canine nervous tumors.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.182.1-182.1
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• 2003

Flavonoids with oxygen atoms are known to have potent biological effect.They have been studied long as major antioxidants which protect cell membranes. Recent medical surveys show that increased intake of selenium decreases the risk of breast, colon, lung and prostrate cancer by preventing free radical generation. The flavonoids, isoflavonoids, and coumarins which form the bulk of these compounds are very polar and have limited use as drugs which have to pass through BBB(Brain Blood Barrier)The non-polar property is increased by exchange oxygen to selenium as a part of heterocyclic compound. (omitted)

• BMB Reports
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• v.33 no.3
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• pp.221-227
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• 2000

The distribution of barbiturates in the model membranes of total lipids (SPMVTL) and total phospholipids (SPMVPL) extracted from synaptosomal plasma membrane vesicles was determined by employing a fluorescent probe technique. The two fluorescent probes 2-(9-anthroyl)stearic acid and 12-(9-anthroyl)stearic acid were utilized as probes for the surface and the hydrocarbon interior of the outer monolayer of the SPMVTL and SPMVPL, respectively. The Stern-Volmer equation of fluorescent quenching was modified to calculate the relative distribution. The analysis of preferential quenching of these probes by barbiturates indicates that pentobarbital, hexobarbital, amobarbital and phenobarbital are predominantly distributed on the surface area, while thiopental sodium has an accessibility to the hydrocarbon interior of the outer monolayer of the SPMVTL and SPMVPL. From these results, it is strongly suggested that the more effective penetration into the hydrocarbon interior of the outer monolayer of the membrane lipid bilayer could result in a higher general anesthetic activity.

• The Korean Journal of Cytopathology
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• v.16 no.2
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• pp.110-114
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• 2005

Primary leptomeningeal glioblastomatosis is a rare and fatal tumor of the central nervous system, the condition is characterized by diffuse infiltration of the tumor in the meninges without evidence of primary tumor within the brain or spinal cord. We reported an unusual case of leptomengial glioblastomatosis, which was detected by the consecutive cerebrospinal fluid (CSF) cytology with application of immunohistochemistry, in addition to its cytologic findings. A healthy 21 year old man, who was enlisted in the army, presented with a stuporous mental state and diffuse enhancement of meninges without evidence of primary mass lesion in the brain and spinal cord on magnetic resonance imaging(MRI). CSF cytology showed small loose clusters of tumor cells with single cells and lymphocytes. The tumor showed variable pleomorphism with coarse chromatin, irregular nuclear membranes and multi lobated nuclei. On immunohistochemical staining, the tumor cells were founded to be positive for GFAP. In conjunction with radiologic findings, brain biopsy confirmed the diagnosis of leptomenigeal glioblastomatosis. The use of immunohistochemistry is helpful in confirming CSF cytologic diagnosis in patients with primary leptomeningeal glioblastomatosis.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.1
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• pp.13-17
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• 1997

Carbamazepine (CBZ), an anticonvulsant, has beeen reported to displace ligands at adenosine receptors. Several studies have demonstrated that as far as $A_2$adenosine receptors is concerned, CBZ acts as an antagonist. However, the situation with regard to Al receptors is less straightforward. In this study, we describe the effects of one-week CBZ treatment (25 mg/kg/day) on cerebrocortical $A_1$ adenosine receptors. $A_1$ adenosine receptor bindings as determined by using $[^3CH]DPCPX$ was not significantly altered in membranes prepared from CBZ-treated rats. However, there was a significant decrease in the $A_1$ adenosine receptor-mediated stimulation of $[^{35}S]GTP_{\gamma}S$ binding to cerebrocortical membranes prepared from CBZ-treated rats (20.0% decrease in basal activity; 17.8% decrease in maximal activity). The basal and $10^{-4}$ M forskolin-stimulated adenylyl cyclase activities were relatively unaffected by CBZ treatment, but 10 mM NaF-stimulated adenylyl cyclase activity was significantly reduced in CBZ-treated rats. It appears that one-week CBZ treatment caused an uncoupling of adenosine receptors from G proteins without alteration of $A_1$ adenosine receptor molecules, suggesting that CBZ acts as an agonist at $A_1$ adenosine receptors in rat brain.

• BMB Reports
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• v.40 no.5
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• pp.617-624
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• 2007

Protein arginine methylation is a posttranslational modification involved in various cellular functions including cell signaling, protein subcellular localization and transcriptional regulation. We analyze the protein arginine methyltransferases (PRMTs) that catalyze the formation of methylarginines in porcine brain. We fractionated the brain extracts and determined the PRMT activities as well as the distribution of different PRMT proteins in subcellular fractions of porcine brain. The majority of the type I methyltransferase activities that catalyze the formation of asymmetric dimethylarginines was in the cytosolic S3 fraction. High specific activity of the methyltransferase was detected in the S4 fraction (high-salt stripping of the ultracentrifugation precipitant P3 fraction), indicating that part of the PRMT was peripherally associated with membrane and ribosomal fractions. The amount and distribution of PRMT1 are consistent with the catalytic activity. The elution patterns from gel filtration and anion exchange chromatography also indicate that the type I activity in S3 and S4 are mostly from PRMT1. Our results suggest that part of the type I arginine methyltransferases in brains, mainly PRMT1, are sequestered in an inactive form as they associated with membranes or large subcellular complexes. Our biochemical analyses confirmed the complex distribution of different PRMTs and implicate their regulation and catalytic activities in brain.

• Journal of Life Science
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• v.10 no.6
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• pp.564-569
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• 2000

This study was designed to investigate the effect of silkworm (Bombyx mori L.) powder on lipofuscin, acetylcholine (ACh) and its related enzyme activities in brain of rats. Sprague-Dawley (SD) male rats ($160{\pm}10g$) were fed basic diet (control group), and experimental diets (SWP-200 and SWP-400 groups) added 200 and 400 mg/kg BW/day for 6 weeks. In case of liver membranes, lipofuscin (LF) levels resulted in a slight decreases (4.6% and 11.5%, respectively) in SWP-200 and SWP-400 groups compared with control group. But in case of barin as the most sensitive organ, LF levels were remarkably inhibited about 16.7% and 20.0% in SWP-200 and SWP-400 groups compared with control group. There were no significant differences in acetylcholine (ACh) syntheses as a very important neurotransmitter, and choline acetyltransferase (ChAT) activities as a synthesis enzyme of ACh, and acetylcholinesterase (AChE) activities as a hydrolysis enzyme, which were concerned in transmission of neuron through synapses in brain of SWP-200 and SWP-400 groups compared with control group. Monoamine oxidase-B (MAO-B) activities were significantly inhibited (about 10.2%) in brain of SWP-400 groups compared with control group. These results suggest that inhibiting effects of LF accumulation and MAO-B activity of silkworm powder (SWP) may play a pivotal role in attenuating a various age-related changes for improvement of brain function.

• Journal of Korean Neurosurgical Society
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• v.60 no.3
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• pp.301-305
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• 2017

Multiloculated hydrocephalus (MLH) is a condition in which patients have multiple, separate abnormal cerebrospinal fluid collections with no communication between them. Despite technical advancements in pediatric neurosurgery, neurological outcomes are poor in these patients and the approach to this pathology remains problematic especially given individual anatomic complexity and cerebrospinal fluid (CSF) hydrodynamics. A uniform surgical strategy has not yet been developed. Current treatment options for MLH are microsurgical fenestration of separate compartments by open craniotomy or endoscopy, shunt surgery in which multiple catheters are placed in the compartments, and combinations of these modalities. Craniotomy for fenestration allows better visualization of the compartments and membranes, and it can offer easy fenestration or excision of membranes and wide communication of cystic compartments. Hemostasis is more easily achieved. However, because of profound loss of CSF during surgery, open craniotomy is associated with an increased chance of subdural hygroma and/or hematoma collection and shunt malfunction. Endoscopy has advantages such as minimal invasiveness, avoidance of brain retraction, less blood loss, faster operation time, and shorter hospital stay. Disadvantages are also similar to those of open craniotomy. Intraoperative bleeding can usually be easily managed by irrigation or coagulation. However, handling of significant intraoperative bleeding is not as easy. Currently, endoscopic fenestration tends to be performed more often as initial treatment and open craniotomy may be useful in patients requiring repeated endoscopic procedures.

• Journal of Nutrition and Health
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• v.37 no.2
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• pp.95-99
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• 2004

This study was designed to investigate the effects of ethyl acetate(EtOAc) fraction of pine (Pinus densiflora Sieb et Zucc) needle on cholesterol and lipofuscin(LF) accumulations, acetylcholine(ACh) and its related enzyme activities such as choline acetyltransferase(ChAT) and acetylcholinesterase(AChE), and monoamine oxidase-B(MAO-B) activity, which destroyed the catecholamine related neurotransmitters in brain membranes of Sprague- Dawley (SD) rats. Male SD rats were fed basic diets (control group) and experimental diets (EtOAc-25, EtOAc-50 and EtOAc-100) for 45 days. Cholesterol accumulations in mitocholndria and microsomes were significantly inhibited (11.8-12.1% and 9.6-13.0%, respectvely) in EtOAc-50 and EtOAc-100 groups. ACh levels and ChAT activities were significantly increased about 10% in membranes of EtOAc-100 group compared with control group. AChE activities were significantly increased about 8 -12% in membranes of EtOAc-50 and EtOAc-100 groups compared with control group. MAO-B activities were significantly inhibited about 10% in membrane of EtOAc-l00 group compared with control group. These results suggest that ethyl acetate fraction of pine needle may play an effective role in inhibiting cholesterol and improving a membrane fluidity, and learning and memory impairments. (Korean J Nutrition 37(2): 95 -99, 2004)