• Title/Summary/Keyword: brain structure

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Phonetics and Language as a formal System

  • Port, Robert F.;Leary, Adam P.
    • Lingua Humanitatis
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    • v.5
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    • pp.221-264
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    • 2003
  • This paper takes issue with the idea of language as a 'serial-time structure' as opposed to the 'real-time event' of speech, an idea entrenched in Chomskyan model of linguistic theory. The discussion centers around the leitmotif question: Is language constructed entirely from a finite set of apriori discrete symbol types, as the 'competence vs performance' dichotomy implies\ulcorner A set of linguistic patterns examined in this study, largely with regard to phonological considerations, points to the evidence to the contrary. That is, while the patterns may be said to be linguistically distinct, they are not discretely, different, i.e. not different enough to be reliably differentiated. It is demonstrated that much of current research in phonology, including the most recent Optimality Theory, is misdirected in that it falsely presupposes a discrete universal phonetic inventory. The main thrust of the present study is that there is no sharp boundary between 'competence' defined as the formal, symbolic, discrete time domain of language and human cognition on the one hand and 'performance' as the continuous, fuzzy, real-time domain of human physiology on the other.

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Flavonoids: An Emerging Lead in the P-glycoprotein Inhibition

  • Gadhe, Changdev G.;Cho, Seung Joo
    • Journal of Integrative Natural Science
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    • v.5 no.2
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    • pp.72-78
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    • 2012
  • Multidrug resistance is a major obstacle in cancer chemotherapy. Cancer cells efflux chemotherapeutic drug out of cell by means of transporter and reduce the active concentration of it inside cell. Such transporters are member of the ATP binding cassettes (ABC) protein. It includes P-gp, multiple resistant protein (MRP), and breast cancer resistant protein (BCRP). These proteins are widely distributed in the human cells such as kidney, lung, endothelial cells of blood brain barrier etc. However, there are number of drugs developed for it, but most of them are getting transported by it. So, still there is necessity of a good modulator, which could effectively combat the transport of chemotherapeutic agents. Natural products origin modulators were found to be effective against transporter such as flavonoids, which belongs to third generation modulators. They have advantage over synthetic inhibitor in the sense that they have simple structure and abundant in nature. This review focuses on the P-gp structure its architecture, efflux mechanism, herbal inhibitors and their mechanism of action.

Strategies for Evolution in Neural Networks based on Cellular Automata (셀룰라 오토마타 기반 신경 회로망의 진화를 위한 전략)

  • Jo, Yong-Goon;Lee, Won-Hee;Kang, Hoon
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2193-2196
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    • 1998
  • Cellular automata are dynamical systems in which space and time are discrete, where each cell has a finite number of states and updates its states by interactive rules among the cell-neighborhood. From the characteristics of self-reproduction and self- organization, it is possible to create a neural network which has the specific patterns or structures dynamically. CAM-Brain is a kind of such neural network system which evolves its structure by adopting evolutionary computations like genetic algorithms (GA). In this paper, we suggest the evolution strategies for the structure of neural networks based on cellular automata.

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Roles of Milk Fat Globule Membrane on Fat Digestion and Infant Nutrition

  • Chai, Changhoon;Oh, Sejong;Imm, Jee-Young
    • Food Science of Animal Resources
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    • v.42 no.3
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    • pp.351-371
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    • 2022
  • Milk fats are present as globules emulsified in the aqueous phase of milk and stabilized by a delicate membrane architecture called milk fat globule membrane (MFGM). The unique structure and composition of the MFGM play an important role in fat digestion and the metabolic programming of neonates. The objective of this review is to compare the structure, composition, and physicochemical characteristics of fat globules in human milk, bovine milk, and infant formula. It provides an overview of the fat digestion process and enzymes in healthy infants, and describes the possible roles of the MFGM in association with factors affecting fat digestion. Lastly, the health benefits of the MFGM on infant nutrition and future perspectives are discussed with a focus on brain development, metabolic response, and gut health.

Molecular Cloning and Expression of cDNAs Encoding Mouse $Gal{\beta}$1,3(4)GlcNAc ${\alpha}$2,3-Sialyltransferase (mST3Gal III) and $Gal{\beta}$1,4(3)GlcNAc ${\alpha}$2,3-Sialyltransferase (mST3GaI IV)

  • Kim, Kyoung-Sook;Kim, Cheorl-Ho;Shin, Deug-Yong;Lee, Young-Choon
    • BMB Reports
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    • v.30 no.2
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    • pp.95-100
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    • 1997
  • Two kinds of cDNA encoding mouse $Gal{\beta}$1,3(4)GlcNAc ${\alpha}$2,3-sialyltransferase (mST3Gal III) and $Gal{\beta}$1,4(3)GlcNAc ${\alpha}$2,3-sialyltransferase (mST3Gal IV) were isolated from mouse brain cDNA library by means of a PCR-based approach. The cDNA sequences included an open reading frame coding for proteins of 374 and 333 amino acids, respectively, and the primary structure of these enzymes suggested a putative domain structure consisting of four regions, like that in other glycosyltransferases. The deduced amino acid sequences of mST3GaI III and IV showed a 98% and 89% identity with rat ST3GaI III and human ST3Gal IV, respectively. Northern analysis indicated that the expression of mST3Gal III mRNA was abundant in heart, liver and adult brain, while that of mST3GaI IV mRNA was detected in all tissues tested except for testis, but the level was the highest in liver. Soluble forms of mST3GaI III and IV transiently expressed in COS cells exhibited enzyme activity toward acceptor substrates containing the terminal either $Gal{\beta}$1,3GlcNAc or $Gal{\beta}$1,4GlcNAc sequences. The substrate preferences of both enzymes were stronger for tetrasaccharides than for disaccharides.

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Miniature PZT actuated microdrive for chronic neural recording in small animals (신경신호 기록을 위한 PZT기반 마이크로 드라이브)

  • Park, Sang-Kyu;Park, Hyun-Jun;Park, Suk-Ho;Kim, Byung-Kyu;Shin, Hee-Sub;Lee, Suk-Chan;Kim, Hui-Su;Kim, Eun-Tai
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.38-40
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    • 2005
  • Microdrive with high precision and light mass enough to install on mouse head was fabricated for recording the reliable signal of neuron cell to understand the brain study. The proposed microdrive has three H-form PZT actuators and its guide structure. The microdrive operation principle is based on the well known inchworm principle. The synchronization of three PZT actuators is able to produce the linear motion along the guide structure. Our proposed microdrive has a precise accuracy of about 100nm and a long stroke of about 5mm. The electrode which is used for the recording of the action potential of the neuron cell was fixed at one of PZT actuators. The proposed microdrive was suited to acquisition of signals from in vivo extra-cellular single-unit recoding. On the condition of the anesthetized mouse, the single-unit signals could be recorded by using the proposed microdrive. In addition, applying the PZT microdrive to an alert mouse, we try to implant it on a mouse brain skull to explore single neuron firing.

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Neurological Dynamic Development Cycles of Abstractions in Math Learning (수학학습의 추상적 개념발달에 대한 뇌신경학적 역동학습 연구)

  • Kwon, Hyungkyu
    • Journal of The Korean Association of Information Education
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    • v.18 no.4
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    • pp.559-566
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    • 2014
  • This is to understand the neurological dynamic cognitive processes of math learning based on the abstract mappings( level A2), abstract systems(level A3), and single principles(level A4), which are principles of Fischer's cognitive development theory. Math learning requires flexibility to adapt existing brain function in selecting new neurophysiological activities to learn desired knowledge. This study suggests a general statistical framework for the identification of neurological patterns in different abstract learning change with optimal support. We expected that functional brain networks derived from a simple math learning would change dynamically during the supportive learning associated with different abstract levels. Task based patterns of the brain structure and function on representations of underlying connectivity suggests the possible prediction for the success of the supportive learning.

Functional analysis of expressed sequence tags from the liver and brain of Korean Jindo dogs

  • Kim, Jae-Young;Park, Hye-Sun;Lim, Da-Jeong;Jang, Hong-Chul;Park, Hae-Suk;Lee, Kyung-Tai;Kim, Jong-Seok;Oh, Seok-Il;Kweon, Mu-Sik;Kim, Tae-Hun;Choi, Bong-Hwan
    • BMB Reports
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    • v.44 no.4
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    • pp.238-243
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    • 2011
  • We generated 16,993 expressed sequence tags (ESTs) from two libraries containing full-length cDNAs from the brain and liver of the Korean Jindo dog. An additional 365,909 ESTs from other dog breeds were identified from the NCBI dbEST database, and all ESTs were clustered into 28,514 consensus sequences using StackPack. We selected the 7,305 consensus sequences that could be assembled from at least five ESTs and estimated that 12,533 high-quality single nucleotide polymorphisms (SNPs) were present in 97,835 putative SNPs from the 7,305 consensus sequences. We identified 58 Jindo dog-specific SNPs in comparison to other breeds and predicted seven synonymous SNPs and ten non-synonymous SNPs. Using PolyPhen, a program that predicts changes in protein structure and potential effects on protein function caused by amino acid substitutions, three of the non-synonymous SNPs were predicted to result in changes in protein function for proteins expressed by three different genes (TUSC3, ITIH2, and NAT2).

Lesion of Subthalamic Nucleus in Parkinsonian Rats : Effects of Dopamine $D_1$ and $D_2$ Receptor Agonists on the Neuronal Activities of the Substantia Nigra Pars Reticulata

  • Park, Yong-Sook;Jeon, Mi-Fa;Lee, Bae-Hwan;Chang, Jin-Woo
    • Journal of Korean Neurosurgical Society
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    • v.42 no.6
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    • pp.455-461
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    • 2007
  • Objective : It was hypothesized that dopamine agonist administration and subthalamic nucleus (STN) lesion in the rat might have a synergistic effect on the neuronal activities of substantia nigra pars reticulata (SNpr) as observed in patients with Parkinson's disease. The effects of SKF38393 (a $D_1$ receptor agonist) and Quinpirole (a $D_2$ receptor agonist) were compared in parkinsonian rat models with 6- hydroxydopamine (6-OHDA) after STN lesion. Methods : SKF38393 and Quinpirole were consecutively injected intrastriatally. SNpr was microrecorded to ascertain the activity of the basal ganglia output structure. The effect of SKF38393 or Quinpirole injection on the firing rate and firing patterns of SNpr was investigated in medial forebrain bundle (MFB) lesioned rats and in MFB+STN lesioned rats. Results : The administration of SKF38393 decreased SNpr neuronal firing rates and the percentage of burst neurons in the MFB lesioned rats, but did not alter them in MFB+STN lesioned rats. The administration of Quinpirole significantly decreased the spontaneous firing rate in the MFB lesioned rats. However, after an additional STN lesion, it increased the percentage of burst neurons. Conclusion : This study demonstrated that dopamine agonists and STN lesion decreased the hyperactive firing rate and the percentage of burst neurons of SNpr neurons in 6-OHDA lesioned rats, respectively. Quinpirole with STN lesion increased a percentage of burst neurons. To clear the exact interactive mechanism of $D_1$ and $D_2$ agonist and the corresponding location, it should be followed a study using a nonselective dopamine agonist and $D_1$, $D_2$ selective antagonist.

Identification of an Embryonic Growth Factor IGF-II from the Central Nervous System of the Teleost, Flounder, and Its Expressions in Adult Tissues

  • Kim, Dong-Soo;Kim, Young-Tae
    • Journal of Microbiology and Biotechnology
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    • v.9 no.1
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    • pp.113-118
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    • 1999
  • The insulin-like growth factor (IGF) is found in all vertebrates and its type-II molecule is regarded as a fundamental embryonic growth factor during development. We have firstly identified, in this study, a cDNA clone corresponding to IGF-II (flIGF-II) from the adult brain of the teleost, Paralichthys olivaceus. We also examined the tissue expression of flIGF-II in several adult tissues by RT-PCR. The flIGF-II cDNA contained a complete ORF consisting of 215 amino acids and one stop codon. Its molecular characteristics appear to be similar to the previously identified IGF-II molecules, in which a common primary structure exhibiting B, C, A, D, and E domains is evidently observed. This cDNA clone seems to be cleaved at $Ala_{52}$ for the $NH_2$-end signal peptide and appears to produce a 98 amino acid-long E-peptide from the $Arg^{118}$. The functional B-D domain regions, therefore, include 65 amino acids and is able to encode a 7.4-kDa protein. The most prominent structural difference between IGF-I and IGF-II was that the D domain of IGF-II exhibits a two-codon-deleted pattern compared to the 8 amino acid-containing IGF-I. The insulin family signature in the A domain and six cysteins forming three disulfide bridges between the B and A domains were evolutionary-conserved from teleosts to mammalian IGF-II. Interestingly, the E-peptide region appears to provide a distinct hallmark between teleosts in amino acid composition. The flIGF-II shows 85.1% of sequence identity to salmon and trout, 90.6% to tilapia, and 98.4% to perch in amino acid level. In tissue expressions of IGF-II, it is very likely that flIGF-II has a significant expression in the adult brain. However, liver seems to be the main source for IGF-II production, and relatively low signals were observed in the adult muscle and kidney. Taken together, it would be concluded that the functional region for IGF-II mRNA is highly similar in phylogeny and is evolutionary, conserved as a mediator for the growth of vertebrates.

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