• Title/Summary/Keyword: Biological mechanism

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Age-specific variations in hematological and biochemical parameters in middle- and large-sized of dogs

  • Lee, Seok Hee;Kim, Jin Wook;Lee, Byeong Chun;Oh, Hyun Ju
    • Journal of Veterinary Science
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    • v.21 no.1
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    • pp.7.1-7.13
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    • 2020
  • Aging triggers cellular and molecular alterations, including genomic instability and organ dysfunction, which increases the risk of disease in mammals. Recently, due to the markedly growing number of aging dogs in the world, as much as 49% in total number of pet dogs, it is necessary to improve and maintain their quality of life by understanding of the biological effects of aging. Therefore, the aim of this study was to determine specific biomarkers in aging dogs as a means of defining a set of hematological/biochemical biomarkers that influence the aging process. Blood samples were collected from younger (1-3 years) and older (7-10 years) dogs of middle/large size. The hematological/biochemistry analysis was performed to evaluate parameters significantly associated with age. Enzyme-linked immunosorbent assay was used to target growth hormone (GH)/insulin growth factor-1 (IGF-1), one of the main regulators of the aging process. Declining levels of total protein and increased levels of glucose in young dogs was observed regardless of their body size. Notably, a significantly high concentration of GH and IGF-1 in the younger dogs compared to the older dogs was found in middle/large-sized dogs. GH and IGF-1 were also found at significantly high levels in large-sized dogs compared to middle-sized dogs, suggesting a similar trend to that of elderly humans. Consequently, glucose, total protein, GH, and IGF-1 were identified as potential biomarkers for regulating the aging process in large/middle-sized dogs. These findings provide an invaluable insight into the mechanism of aging for the field of aging research.

A Comparative Analysis of Motor Imagery, Execution, and Observation for Motor Imagery-based Brain-Computer Interface (움직임 상상 기반 뇌-컴퓨터 인터페이스를 위한 운동 심상, 실행, 관찰 뇌파 비교 분석)

  • Daeun, Gwon;Minjoo, Hwang;Jihyun, Kwon;Yeeun, Shin;Minkyu, Ahn
    • Journal of Biomedical Engineering Research
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    • v.43 no.6
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    • pp.375-381
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    • 2022
  • Brain-computer interface (BCI) is a technology that allows users with motor disturbance to control machines by brainwaves without a physical controller. Motor imagery (MI)-BCI is one of the popular BCI techniques, but it needs a long calibration time for users to perform a mental task that causes high fatigue to the users. MI is reported as showing a similar neural mechanism as motor execution (ME) and motor observation (MO). However, integrative investigations of these three tasks are rarely conducted. In this study, we propose a new paradigm that incorporates three tasks (MI, ME, and MO) and conducted a comparative analysis. For this study, we collected Electroencephalograms (EEG) of motor imagery/execution/observation from 28 healthy subjects and investigated alpha event-related (de)synchronization (ERD/ERS) and classification accuracy (left vs. right motor tasks). As result, we observed ERD and ERS in MI, MO and ME although the timing is different across tasks. In addition, the MI showed strong ERD on the contralateral hemisphere, while the MO showed strong ERD on the ipsilateral side. In the classification analysis using a Riemannian geometry-based classifier, we obtained classification accuracies as MO (66.34%), MI (60.06%) and ME (58.57%). We conclude that there are similarities and differences in fundamental neural mechanisms across the three motor tasks and that these results could be used to advance the current MI-BCI further by incorporating data from ME and MO.

Anti-Melanogenic Effect of Thymol, a Major Odorant in Essential Oils of Family Lamiaceae (꿀풀과 식물 정유의 주성분인 Thymol의 미백활성에 관한 연구)

  • Choi, Deok-Gyun;Park, Chan Ik;Lee, Sun-Mi;Baek, Jeong-In
    • The Korea Journal of Herbology
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    • v.34 no.4
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    • pp.19-25
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    • 2019
  • Objectives : Thymol (2-isopropyl-5-methylphenol), a natural monoterpenoid phenol, is one of the major odorant constituents found in natural essential oils of various herbal plants, such as Thymus quinquecostatus and Thymus vulgaris. Multiple biological activities of thymol, including antioxidative, antimicrobial, and anti-inflammatory effects, have been reported in numerous in vitro studies, and recently it was suggested that thymol may could inhibit oxidization of L-dihydroxyphenylalanine (L-DOPA) to dopaquinone required in melanogenesis pathway, as an antioxidant. Methods : MTT assay was performed to test the cytotoxic effect of thymol in B16F10 cells. Inhibitory effect of thymol to tyrosinase activities were examined using both mushroom tyrosinase and intracellular tyrosinase. Expression level of tyrosinase in B16F10 cells were investigated by western blot analysis. Results : The cell viability was decreased by thymol treatment in dose-dependant manner, leading significant cytotoxicity in 500 and $1000{\mu}M$ thymol-treated groups. In the alpha-melanocyte stimulating hormone (${\alpha}$-MSH)-induced melanogenesis, administration of thymol significantly decreased extracellular (secreted) melanin content in dose-dependent manner. Cellular tyrosinase activity assay and western blot analysis of intracellular tyrosinase showed that thymol has a strong anti-melanogenic effect by inhibition of tyrosinase activity and by decreasing expression of tyrosinase that contribute to melanin synthesis in the B1610 cells. Conclusions : As the first functional study that prove anti-melanogenic effect of thymol and its underlying mechanism in the living cells, our study suggests the applicability of fragrance as the functional materials of cosmetics or health supplement, not as just an additive.

Classification of Insects Collected in Historical Wooden Building (목조 고건축물에서 채집된 곤충의 분류)

  • Jeong, In-Soo;Lee, Yang-Soo;Lee, Hee-Kwon
    • Journal of the Korean Wood Science and Technology
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    • v.31 no.2
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    • pp.52-57
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    • 2003
  • This research is to collect, classify and identify the insects boring tunnels into wood or damaging wooden frame structure. Intensive insect collections have been carried at the historical local schools annexed to the confucian shrine from March to September 2001. Ten species of Coleoptera, 15 species of Hymenoptera, 6 species of Hemiptera, 4 species of Ditera and 1 species of Demaptera were recorded. Most species of Coleoptera and Hymenoptera have the manducatory apparatus in the mouth-part that cause severe damage in wood, and showed the highest population among the genera recorded. Further research should be considered on the identification of wood demage insects at the species level among present collection and their mechanism of wood demage in the wood.

Constitutive Activating Eel Luteinizing Hormone Receptors Induce Constitutively Signal Transduction and Inactivating Mutants Impair Biological Activity

  • Byambaragchaa, Munkhzaya;Choi, Seung-Hee;Kim, Dong-Wan;Min, Kwan-Sik
    • Development and Reproduction
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    • v.25 no.3
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    • pp.133-143
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    • 2021
  • In contrast to the human lutropin receptor (hLHR) and rat LHR (rLHR), very few naturally occurring mutants in other mammalian species have been identified. The present study aimed to delineate the mechanism of signal transduction by three constitutively activating mutants (designated M410T, L469R, and D590Y) and two inactivating mutants (D383N and Y546F) of the eel LHR, known to be naturally occurring in human LHR transmembrane domains. The mutants were constructed and measured cyclic adenosine monophosphate (cAMP) accumulation via homogeneous time-resolved fluorescence assays in Chinese hamster ovary (CHO)-K1 cells. The activating mutant cells expressing eel LHR-M410T, L469R, and D590Y exhibited a 4.0-, 19.1-, and 7.8-fold increase in basal cAMP response without agonist treatment, respectively. However, inactivating mutant cells expressing D417N and Y558F did not completely impaired signal transduction. Specifically, signal transduction in the cells expressing activating mutant L469R was not occurred with a further ligand stimulation, showing that the maximal response exhibited approximately 53% of those of wild type receptor. Our results suggested that the constitutively activating mutants of the eel LHR consistently occurred without agonist treatment. These results provide important information of LHR function in fish and regulation with regard to mutations of highly conserved amino acids in glycoprotein hormone receptors.

Pheromone Biosynthesis Activating Neuropeptide (PBAN) in Insects (곤충의 페로몬 생합성 활성화 신경펩타이드(PBAN))

  • Choi, Man-yeon
    • Korean journal of applied entomology
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    • v.61 no.1
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    • pp.15-28
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    • 2022
  • Neuropeptides produced in neurosecretory cells are the largest group of insect hormones. They regulate various physiological functions, such as fat body homeostasis, feeding, digestion, excretion, circulation, reproduction, metamorphosis, and behavior throughout all life stages. The PRXamide peptide family (X, a variable amino acid) is a well-characterized neuropeptide component with a common amino acid sequence, PRXamide (NH2), at the C-terminal end conserved across Insecta. The PRXamide peptides are classified into three subfamilies, each having diverse biological roles in insects: (1) pyrokinin (PK) includes the pheromone biosynthesis activating neuropeptide (PBAN) and the diapause hormone (DH), (2) the capability (CAPA) peptides, and (3) the ecdysis-triggering hormone (ETH). PBAN as a member of PK subfamily was first identified to stimulate pheromone biosynthesis in moths three decades ago. Since then, PBAN peptides have been extensively studied by various research groups from a broad spectrum of arthropods. In this paper, we briefly review insect PBAN molecules with emphasis on gene structure and expression, signal transduction, physiological mechanism in sex pheromone biosynthesis, and application for pest management.

In-vitro Antimalarial Investigations and Molecular Docking Studies of Compounds from Trema orientalis L. (blume) Leaf Extract

  • Samuel, Babatunde Bolorunduro;Oluyemi, Wande Michael;Okedigba, Ayoyinka Oluwaseun
    • Natural Product Sciences
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    • v.28 no.2
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    • pp.45-52
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    • 2022
  • The identification of Plasmodium falciparum enoyl acyl-carrier protein reductase (pfENR) is considered as a potential biological target against malaria. Trema orientalis is considered a rich source of phytochemicals useful in malaria treatment. This study evaluated the in-vitro inhibitory activity of the extract and isolated compounds of T. orientalis leaf; the isolated compounds and the analogues of the most active compound were subjected to in-silico molecular docking studies on pfENR. The methanolic extract of T. orientalis was subjected to repeated chromatographic separation which led to the isolation of some compounds. The isolated compounds from the plant were examined for their antimalarial activity using β-hematin inhibition assay. Virtual screening via molecular docking and ADMET studies were conducted to gain insight into the mechanism of binding of ligand and to identify effective pfENR inhibitors. The isolated compounds and the analogues of the most active isolates were gotten from PubChem library for use in docking study. Hexacosanol and β-sitosterol showed inhibition of the β-hematin formation. The docking results showed that hexacosanol, β-sitosterol and the analogues of β-sitosterol displayed binding energy ranging between -6.1 kcal/mol and -11.6 kcal/mol. Sitosterol glucoside has the highest docking score. Some of the ligands showed more binding affinity than known bioactive compounds used as reference. Analogues of β-sitosterol has been shown to be potential inhibitors of pfENR, therefore, the findings from this study suggest that sitosterol glucoside and ergosterol peroxide could act as antimalarial agents after further lead optimisation investigations.

Molecular Biological Studies on Korean Garlic Viruses

  • Choi, Jin-Nam;Song, Jong-Tae;Shin, Chan-Seok;La, Yong-Joon;Lee, Jong-Seob;Choi, Yang-Do
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 1994.06a
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    • pp.86-102
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    • 1994
  • To understand the molecular structure and pathogenesis mechanism of Korean garlic viruses, we have isolate cDNA clones for garlic viruses. The partial nucleotide sequences of 24 cDNA clones were determined and that of six clones containing poly (A) tail were compared with those of other plant viruses. One of those clones, V9 has 81.8% similarity in nucleotide sequence and 93.0% in deduced amino acid sequence, respectively, to the coat protein gene for garlic mosaic virus (GMV). Northern blot analysis with the clone V9 demonstrated that the genome of GMV is 7.8 kb long and has poly (A) tail. The anti-coat protein antibody for GMV recognizes 35 kDa polypeptide which could be the coat protein of GMV from infected garlic leaf extract or virus preparation. Clone G7 has about 62% of deduced amino acid sequence identity with the members of potyvirus group. Northern blot analysis with the clone G7 demonstrated that the genome of the potyvirus I garlic is 9.0 kb long and has poly (A) tail. The third clone, S81, shows 42% amino acid identity to the potexvirus. The other clones are under the characterization. To test the possibility of producing garlic virus resistant plant, we have designed a hairpin type ribozyme to cleave V9 RNA at the middle of the coat protein gene. From the cleavage reactions in vitro with two different sizes of RNA substrates, V9SUB (144 nucleotides) and V9 RNA (1,361 nucleotides), the ribozyme can cleave V9 sequence effectively at the predicted site. To study the activity of the ribozyme in vivo, plant transformation is in progress. Further possibilities to produce garlic virus resistant plant will be discussed.

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A NEW BIOPOLYMER FOR REFRESHMENT

  • Bozou, J.C.;Gautry, L.;Pianelli, G.
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.480-490
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    • 2003
  • An innovative biopolymer known as the Rhizobian gum has been developed in France, which shows some dramatic refreshing effect on the skin. The origin of this innovative project takes its source in the natural environment, and in particular the natural environment of the roots of sunflowers and wheat, where a symbiotic bacterium has been discovered. It is a Rhizobium bacterium, which is hosted by the roots, and which is able to synthesize a specific polymer showing a dramatic water binding capacity. This polymer is in particular synthesized in period of drought, and its biological role is to concentrate the small amount water present in the soil in order to take it available for the root, which becomes then able to absorb it. This vital mechanism allows the plant to survive despite a severe climatic environment. This basic research has been conducted in collaboration whit the French National centre of scientific Research (CNRS), and has lead to the isolation of the Rhizobium bacteria. Rhizobian gum is a branched biopolymer consisting in the repetition of a polysaccharide unit of 3 molecules of glucose, 3 molecules of galactose and 1 molecule of glucuronic acid, whit one pyruvate group an average 1.6 acetyl groups. The fresh effect of Rhizobian gum is a strong sensorial impact that 100 % of the consumers are able to perceive, and which is judged very pleasant by most of them. In addition to this, a large majority of consumers are perceived, and which is judge very pleasant by most of them. In addition to this, a large majority of consumers also feel a very pleasant relaxing sensation. Smoothness and softness are also felt by most consumers and qualified positively by most of them. These qualities guarantee a strong impact on today's consumers.

  • PDF

A NEW BIOPOLYMER FOR REFRESHMENT

  • Bozou, J.C.;Gautry, L.;Pianelli, G.
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.50-60
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    • 2003
  • An innovative biopolymer known as the Rhizobian gum has been developed in France, which shows some dramatic refreshing effect on the skin. The origin of this innovative project takes its source in the natural environment, and in particular the natural environment of the roots of sunflowers and wheat, where a symbiotic bacterium has been discovered. It is a Rhizobium bacterium, which is hosted by the roots, and which is able to synthesize a specific polymer showing a dramatic water binding capacity. This polymer is in particular synthesized in period of drought, and its biological role is to concentrate the small amount water present in the soil in order to take it available for the root, which becomes then able to absorb it. This vital mechanism allows the plant to survive despite a severe climatic environment. This basic research has been conducted in collaboration whit the French National centre of scientific Research (CNRS), and has lead to the isolation of the Rhizobium bacteria. Rhizobian gum is a branched biopolymer consisting in the repetition of a polysaccharide unit of 3 molecules of glucose, 3 molecules of galactose and 1 molecule of glucuronic acid, whit one pyruvate group an average 1.6 acetyl groups. The fresh effect of Rhizobian gum is a strong sensorial impact that 100 % of the consumers are able to perceive, and which is judged very pleasant by most of them. In addition to this, a large majority of consumers are perceived, and which is judge very pleasant by most of them. In addition to this, a large majority of consumers also feel a very pleasant relaxing sensation. Smoothness and softness are also felt by most consumers and qualified positively by most of them. These qualities guarantee a strong impact on today's consumers.

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