• Title/Summary/Keyword: Memory function

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PLZF+ Innate T Cells Support the TGF-β-Dependent Generation of Activated/Memory-Like Regulatory T Cells

  • Kang, Byung Hyun;Park, Hyo Jin;Park, Hi Jung;Lee, Jae-Il;Park, Seong Hoe;Jung, Kyeong Cheon
    • Molecules and Cells
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    • v.39 no.6
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    • pp.468-476
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    • 2016
  • PLZF-expressing invariant natural killer T cells and CD4 T cells are unique subsets of innate T cells. Both are selected via thymocyte-thymocyte interaction, and they contribute to the generation of activated/memory-like CD4 and CD8 T cells in the thymus via the production of IL-4. Here, we investigated whether $PLZF^+$ innate T cells also affect the development and function of $Foxp3^+$ regulatory CD4 T cells. Flow cytometry analysis of the thymus and spleen from both CIITA transgenic C57BL/6 and wild-type BALB/c mice, which have abundant $PLZF^+$ CD4 T cells and invariant natural killer T cells, respectively, revealed that $Foxp3^+$ T cells in these mice exhibited a $CD103^+$ activated/memorylike phenotype. The frequency of $CD103^+$ regulatory T cells was considerably decreased in $PLZF^+$ cell-deficient $CIITA^{Tg}Plzf^{lu/lu}$ and $BALB/c.CD1d^{-/-}$ mice as well as in an IL-4-deficient background, such as in $CIITA^{Tg}IL-4^{-/-}$ and $BALB/c.IL-4^{-/-}$ mice, indicating that the acquisition of an activated/ memory-like phenotype was dependent on $PLZF^+$ innate T cells and IL-4. Using fetal thymic organ culture, we further demonstrated that IL-4 in concert with TGF-${\beta}$ enhanced the acquisition of the activated/memory-like phenotype of regulatory T cells. In functional aspects, the activated/ memory-like phenotype of Treg cells was directly related to their suppressive function; regulatory T cells of $CIITA^{Tg}PIV^{-/-}$ mice more efficiently suppressed ovalbumin-induced allergic airway inflammation compared with their counterparts from wild-type mice. All of these findings suggest that $PLZF^+$ innate T cells also augmented the generation of activated/memory-like regulation via IL-4 production.

Wall Cuckoo: A Method for Reducing Memory Access Using Hash Function Categorization (월 쿠쿠: 해시 함수 분류를 이용한 메모리 접근 감소 방법)

  • Moon, Seong-kwang;Min, Dae-hong;Jang, Rhong-ho;Jung, Chang-hun;NYang, Dae-hun;Lee, Kyung-hee
    • KIPS Transactions on Computer and Communication Systems
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    • v.8 no.6
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    • pp.127-138
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    • 2019
  • The data response speed is a critical issue of cloud services because it directly related to the user experience. As such, the in-memory database is widely adopted in many cloud-based applications for achieving fast data response. However, the current implementation of the in-memory database is mostly based on the linked list-based hash table which cannot guarantee the constant data response time. Thus, cuckoo hashing was introduced as an alternative solution, however, there is a disadvantage that only half of the allocated memory can be used for storing data. Subsequently, bucketized cuckoo hashing (BCH) improved the performance of cuckoo hashing in terms of memory efficiency but still cannot overcome the limitation that the insert overhead. In this paper, we propose a data management solution called Wall Cuckoo which aims to improve not only the insert performance but also lookup performance of BCH. The key idea of Wall Cuckoo is that separates the data among a bucket according to the different hash function be used. By doing so, the searching range among the bucket is narrowed down, thereby the amount of slot accesses required for the data lookup can be reduced. At the same time, the insert performance will be improved because the insert is following up the operation of the lookup. According to analysis, the expected value of slot access required for our Wall Cuckoo is less than that of BCH. We conducted experiments to show that Wall Cuckoo outperforms the BCH and Sorting Cuckoo in terms of the amount of slot access in lookup and insert operations and in different load factor (i.e., 10%-95%).

Effects of Water Extract of Smoke-dried Skipjack Tuna on Memory in a Scopolamine-induced Amnesia Animal Model

  • Lim, Soon-Sung;Hwang, In-Koo;Yoo, Ki-Yeon;Kang, Il-Jun;Shin, Hyun-Kyung;Kim, Sang-Moo;Won, Moo-Ho
    • Food Science and Biotechnology
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    • v.17 no.3
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    • pp.594-597
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    • 2008
  • Natural products have been used to treat many neurological illnesses such as Alzheimer's disease. In the present study, the effects of the water extract of smoke-dried skipjack tuna (WSST), which is used as a traditional seasoning in Japan, as well as its fractions on acetylcholinesterase (AChE) inhibition in vitro and on memory in scopolamine-induced amnesia mice in vivo were evaluated. Bio-Rad P-2 gel permeation chromatography revealed the presence of 7 peaks and AChE significantly inhibited peak 3 and 5. When in vivo behavioral studies were conducted, a passive avoidance test revealed that treatment with 50 and 100 mg/kg WSST as well as with fraction 3 and 5 improved the loss in memory retention induced by scopolamine. These results suggest that skipjack tuna extract and its fractions improve memory deficits and that these substances are suitable for use in healthy foods designed to improve memory deficits induced by aging and Alzheimer's disease.

Hypothermia alleviates hypoxic ischemia-induced dopamine dysfunction and memory impairment in rats

  • Ko, Il-Gyu;Cho, Han-Jin;Kim, Sung-Eun;Kim, Ji-Eun;Sung, Yun-Hee;Kim, Bo-Kyun;Shin, Mal-Soon;Cho, Seh-Yung;KimPak, Young-Mi;Kim, Chang-Ju
    • Animal cells and systems
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    • v.15 no.4
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    • pp.279-286
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    • 2011
  • Hypoxic ischemia injury is a common cause of functional brain damage, resulting from a decrease in cerebral blood flow and oxygen supply to the brain. The main problems associated with hypoxic ischemia to the brain are memory impairment and dopamine dysfunction. Hypothermia has been suggested to ameliorate the neurological impairment induced by various brain insults. In this study, we investigated the effects of hypothermia on memory function and dopamine synthesis following hypoxic ischemia to the brain in rats. For this purpose, a step-down avoidance task, a radial eight-arm maze task, and immunohistochemistry for tyrosine hydroxylase (TH) and 5-bromo-2'-deoxyuridine (BrdU) were performed. The present results indicated that the hypoxic ischemia-induced disturbance of the animal's performances and spatial working memory was associated with a decrement in TH expression in the substantia nigra and striatum, and an increase in cell proliferation in the hippocampal dentate gyrus. Hypothermia treatment improved the animals' performance and spatial working memory by suppressing the decrement in TH expression in the substantia nigra and striatum and the increase in cell proliferation in the dentate gyrus. We suggest that hypothermia can be an efficient therapeutic modality to facilitate recovery following hypoxic ischemia injury to the brain, presumably by modulating the dopaminergic cell loss.

Low-salt Todarodes pacificus Jeotgal improves the Learning and Memory Impairments in Scopolamine-induced Dementia Rats (Scopolamine으로 유발한 치매유도 쥐에 대한 저염 오징어 (Todorodes pacificus) 젓갈의 인지 및 기억손상의 개선효과)

  • Heo, Jin-Sun;Kim, Jong-Bok;Cho, Soon-Young;Sohn, Kie-Ho;Choi, Jong-Won
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.47 no.3
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    • pp.195-203
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    • 2014
  • We investigated the effect low salt (2 or 4% salt) concentrations jeotgal made from Todarodes pacificus on the learning and memory impairments in scopolamine-induced (2 mg/kg, i.p.) dementia rats. Rats treated with oral BF-7 (200 mg/kg, p.o.) as a positive control and Todarodes pacificus jeotgal had significantly reduced scopolamine-induced memory deficits in the passive avoidance test. The Morris water maze test or treatment with 2% salt jeotgal made from Todarodes pacificus significantly ameliorated the scopolamine-induced memory deficits in the formation of long- and short-term memory. The acetylcholine content and acetylcholinesterase acitivity paralleled the results of the behavior experiment. There were no significant differences in the brain acetylcholine contents of the experimental groups, while the brain acetylcholine content of the group treated with 2% salt Todarodes pacificus jeotgal was higher than that of the control group. The inhibitory effect of 2% salt jeotgal made from Todarodes pacificus on the acetylcholinesterase activity in the brain was lower than that of the control group. These trends were similar to those of the gamma-aminobutyric acid content. We suggest that Todarodes pacificus jeotgal enhances learning memory and cognitive function by regulating cholinergic enzymes.

Effects of Treadmill Exercise on Memory, Hippocampal Cell Proliferation, BDNF, TrkB, and Forebrain Cholinergic Cells in Adolescent Rats (트레드밀 운동이 청소년기 흰쥐의 기억력과 해마 신경세포생성, BDNF, TrkB, 그리고 전뇌 콜린 세포에 미치는 영향)

  • Lee, Hee-Hyuk
    • Journal of Life Science
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    • v.19 no.3
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    • pp.403-410
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    • 2009
  • This study investigated the effects of treadmill exercise on memory ability, cell proliferation, BDNF, and TrkB in the hippocampus and forebrain cholinergic cells in adolescent rats. Male Sprague-Dawley rats (4 weeks old) were randomly assigned to the following two groups: the sedentary group (n=10) and the exercise group (n=10). Rats in the exercise group were forced to run on a treadmill for 30 min, five times per week for 4 weeks. The latency of the step-through avoidance task was used in order to evaluate memory ability. Hippocampal brain-derived neurotrophic factor (BDNF) and tropomyosin-related kinase B (TrkB) expression were assessed by Western blotting. Hippocampal cell proliferation and forebrain cholinergic cells were assessed by immunohistochemistry. The present study showed that treadmill running during the adolescent period significantly improved memory capability, increased hippocampal cell proliferation, up-regulated hippocampal BDNF and TrkB expression, and enhanced the number of forebrain cholinergic cells. These results suggest that regular exercise during the adolescent period may enhance memory function.

Mentha arvensis Attenuates Cognitive and Memory Impairment in Scopolamine-treated Mice (Scopolamine 처리에 의한 인지 및 기억력 손상 마우스에서 박하의 효과)

  • Lee, Jihye;Kim, Hye-Jeong;Jang, Gwi Yeong;Seo, Kyung Hye;Kim, Mi Ryeo;Choi, Yun Hee;Jung, Ji Wook
    • Korean Journal of Pharmacognosy
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    • v.51 no.1
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    • pp.70-77
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    • 2020
  • Mentha arvensis is used traditional medicine to treat various disorders. In the present study, M. arvensis were extracted by the solid-phase microextraction (SPME) method and analyzed by gas chromatograph-mass spectrometry (GC-MS). We investigated the protective effects and mechanisms of a M. arvensis extract on scopolamine-induced cognitive and memory impairment. Mice were orally pretreated with a M. arvensis extract or normal saline, and then behavior tests were conducted 30 min after scopolamine injection. The antioxidant capacities were analyzed by free radical scavenging (DPPH and ABTS). Acetylcholinesterase (AChE) activity were also measured using Ellman's method ex vivo test. In behavior tests, percent of spontaneous alteration, escape latency and swimming time in target quadrant were improved by the administration of the M. arvensis extract, which suggests that the M. arvensis extract improves memory function in the scopolamine-treated mice model. In addition, M. arvensis extract showed inhibition of the free radical and AChE activity. The results of the present study suggest that the M. arvensis extract ameliorates scopolamine-induced cognitive and memory deficits through the inhibition of free radicals and AChE activity. Therefore, M. arvensis may be a promising neuroprotective agent for management of learning and memory improvements in human dementia patients.

Therapeutic Potential of Jeongjihwan for the Prevention and Treatment of Amnesia (정지환(定志丸)의 기억 및 인지기능 향상에 대한 효능 연구)

  • Jung, Tae-Young;Jeong, Won-Choon;Park, Jong-Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.25 no.1
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    • pp.37-47
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    • 2011
  • This study was aimed to investigate the memory enhancing effect of Jeongjihwan against scopolamine-induced amnesia in C57BL/6 mice. To determine the effect of Jeongjihwan on the memory and cognitive function, we have injected scopolamine (1 mg/kg, i.p.) into C57BL/6 mice 30 min before beginning of behavior tests. We have conducted Y-maze, Morris water-maze, passive avoidance and fear conditioning tests to compare learning and memory functions. Scopolamine-induced behavior changes of memory impairment were significantly restored by oral administration of Jeongjihwan (100 or 200 mg/kg/day). To elucidate the molecular mechanism underlying the memory enhancing effect of Jeongjihwan, we have examined the antioxidant defense system and neurotrophic factors. Jeongjihwan treatment attenuated intracellular accumulation of reactive oxygen species and up-regulated mRNA and protein expression of antioxidant enzymes as assessed by RT-PCR and western blot analysis, respectively. Jeongjihwan also increased protein levels of brain-derived neurotrophic factor (BDNF) compared with those in the scopolamine-treated group. Furthermore, as an upstream regulator, the activation of cAMP response element-binding protein (CREB) via phosphorylation was assessed by Western blot analysis. Jeongjihwan elevated the phosphorylation of CREB (p-CREB), which seemed to be mediated partly by extracellular signal-regulated kinase1/2 (ERK1/2) and protein kinase B/Akt. These findings suggest that Jeongjihwan may have preventive and therapeutic potential in the management of amnesia.

Optimum design and vibration control of a space structure with the hybrid semi-active control devices

  • Zhan, Meng;Wang, Sheliang;Yang, Tao;Liu, Yang;Yu, Binshan
    • Smart Structures and Systems
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    • v.19 no.4
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    • pp.341-350
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    • 2017
  • Based on the super elastic properties of the shape memory alloy (SMA) and the inverse piezoelectric effect of piezoelectric (PZT) ceramics, a kind of hybrid semi-active control device was designed and made, its mechanical properties test was done under different frequency and different voltage. The local search ability of genetic algorithm is poor, which would fall into the defect of prematurity easily. A kind of adaptive immune memory cloning algorithm(AIMCA) was proposed based on the simulation of clone selection and immune memory process. It can adjust the mutation probability and clone scale adaptively through the way of introducing memory cell and antibody incentive degrees. And performance indicator based on the modal controllable degree was taken as antigen-antibody affinity function, the optimization analysis of damper layout in a space truss structure was done. The structural seismic response was analyzed by applying the neural network prediction model and T-S fuzzy logic. Results show that SMA and PZT friction composite damper has a good energy dissipation capacity and stable performance, the bigger voltage, the better energy dissipation ability. Compared with genetic algorithm, the adaptive immune memory clone algorithm overcomes the problem of prematurity effectively. Besides, it has stronger global searching ability, better population diversity and faster convergence speed, makes the damper has a better arrangement position in structural dampers optimization leading to the better damping effect.

Milk Containing BF-7 Enhances the Learning and Memory, Attention, and Mathematical Ability of Normal Persons

  • Kim, Do-Hee;Lee, Hyun-Jung;Choi, Gooi-Hun;Kim, Ok-Hyeon;Lee, Kwang-Gill;Yeo, Joo-Hong;Lee, Jun-Young;Lee, Sang-Hyung;Youn, Young-Chul;Lee, Jang-Han;Paik, Hyun-Dong;Lee, Won-Bok;Kim, Sung-Su;Jung, Hee-Yeon
    • Food Science of Animal Resources
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    • v.29 no.2
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    • pp.278-282
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    • 2009
  • Previous studies indicate that BF-7 enhances learning and memory in normal and elderly individuals. Here, we evaluated whether milk containing BF-7 (BF-7 milk) could improve the brain function, with thirty normal university students $(21{\pm}1.2 years)$. Two versions of the Paced Auditory Serial Addition Test were used under double-blinded conditions to measure the efficacy of BF-7 milk on learning and memory, especially working memory and attention, and on mathematical ability. As a result, BF-7 milk improved the accuracy of the task more than 3-fold. Furthermore, BF-7 milk protected cultured neuronal cells from 3-hydroxykynurenine, a normal endogenous brain stress agent. These results indicate that BF-7 milk enhances memory, attention and mathematical ability in normal persons.