• Title/Summary/Keyword: Physiological models

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Physiology of Cellular Prion Proteins in Reproduction

  • Zeljko M. Svedruzic;Chongsuk Ryou;Donchan Choi;Sung-Ho Lee;Yong-Pil Cheon
    • Development and Reproduction
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    • v.28 no.2
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    • pp.29-36
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    • 2024
  • Cellular prion protein (PrPC) encoded at Prnp gene is well-known to form a misfolded isoform, termed scrapie PrP (PrPSC) that cause transmissible degenerative diseases in central nervous system. The physiological role of PrPC has been proposed by many studies, showing that PrPC interacts with various intracellular, membrane, and extracellular molecules including mitochondrial inner membrane as a scaffold. PrPC is expressed in most cell types including reproductive organs. Numerous studies using PrPC knockout rodent models found no obvious phenotypic changes, in particular the clear phenotypes in development and reproduction have not demonstrated in these knockout models. However, various roles of PrPC have been evaluated at the cellular levels. In this review, we summarized the known roles of PrPC in various cell types and tissues with a special emphasis on those involved in reproduction.

Lack of Any Association of GST Genetic Polymorphisms with Susceptibility to Ovarian Cancer - a Meta-analysis

  • Han, Li-Yuan;Liu, Kui;Lin, Xia-Lu;Zou, Bao-Bo;Zhao, Jin-Shun
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.15
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    • pp.6131-6136
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    • 2014
  • Objective: Epidemiology studies have reported conflicting results between glutathione S-transferase Mu-1 (GSTM1), glutathione S-transferase theta-1 (GSTT1) and glutathione S-transferase pi-1 (GSTP1) and ovarian cancer (OC) susceptibility. In this study, an updated meta-analysis was applied to determine whether the deletion of GSTM1, GSTT1 and GSTP1 has an influence on OC susceptibility. Methods: A published literature search was performed through PubMed, Embase, Cochrane Library, and Science Citation Index Expanded database for articles published in English. Pooled odds ratios (ORs) and 95% confidence intervals (95%CIs) were calculated using random or fixed effects models. Heterogeneity between studies was assessed using the Cochrane Q test and $I^2$ statistics. Sub-group analysis was conducted to explore the sources of heterogeneity. Sensitivity analysis was employed to evaluate the respective influence of each study on the overall estimate. Results: In total, 10 published studies were included in the final analysis. The combined analysis revealed that there was no significant association between GSTM1 null genotype and OC risk (OR=1.01, 95%CI: 0.91-1.12). Additionally, there was no significant association between GSTT1 genetic polymorphisms and OC risk (OR=0.98, 95% CI: 0.85-1.13). Similalry, no significant associations were found concerning the GSTP1 rs1695 locus and OC risk. Meanwhile, subgroup analysis did not show a significant increase in eligible studies with low heterogeneity. However, sensitivity analysis, publication bias and cumulative analysis demonstrated the reliability and stability of the current meta-analysis. Conclusions: These findings suggest that GSTs genetic polymorphisms may not contribute to OC susceptibility. Large epidemiological studies with the combination of GSTM1 null, GSTT1 null and GSTP1 Ile105Val polymorphisms and more specific histological subtypes of OC are needed to prove our findings.

Neuroprotective Effects of Daebowonjeon on PC12 Cells Exposed to Ischemia (허혈 상태의 PC12 세포에 대한 대보원전(大補元煎)의 신경보호효과)

  • Kim, Bong-Sang;Lee, Sun-Woo;Moon, Byung-Soon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.1
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    • pp.117-125
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    • 2007
  • Neuronal ischemia is a pathological process caused by a lack of oxygen (anoxia) and glucose (hypoglycemia), resulting in neuronal death. It is believed that apoptosis is one of the mechanisms involved in ischemic cell death. Neuronal apoptosis is a process characterized by nuclear DNA fragmentation, changes of plasma membrane organization. To elucidate the mechanism of neuronal death following ischemic insult and to develop neuroprotective effects of Daebowonjeon(DBWJ) against ischemic damage, in vitro models are used. In vitro models of cell death have been devloped with pheochromocytoma (PC12) cell, which have become widely used as neuronal models of oxidative stress, trophic factor, serum deprivation and chemical hypoxia. Using a special ischemic device and PC12 cultures, we investigated an in vitro model of ischemia based on combined Oxygen and Glucose Deprivation (OGD) insult, followed by reoxygenation, mimicking the pathological conditions of ischemia. In this study, Daebowonjeon rescued PC12 cells from Oxygen-Glucose Deprivation (OGD)-induced cell death in a dose-dependent manner The nuclear staining of PC12 cells clearly showed that DBWJ attenuated nuclear condensation and fragmentation which represent typical neuronal apoptotic characteristics. DBWJ also prevents the LDH release and induction of Hypoxia Inducing Factor (HIF)-1 by OGD-exposed PC12 cells. Furthermore, DBWJ reduced the activation of polyADP-ribose polymerase (PARP) by OGO-exposed PC12 cells. These results suggest that apoptosis is an important characteristic of OGD-induced neuronal death and that oriental medicine, such as DBWJ, may prevent PC12 cell from OG D-induced neuronal death by inhibiting the apoptotic process.

Study on the Immune Modulatory Activity of Seokjahaeki-tang Using Atopic Dermatitis Animal Models (아토피피부염 동물 병태 모델에서 석자해기탕(石紫解肌湯)의 면역조절작용에 관한 연구)

  • Lee, Byung-Woong;Gim, Seon-Bin;Song, Hyang-Hee;Ji, Joong-Gu;Bak, Ji-Won;Kim, Dong-Hee
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.4
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    • pp.446-454
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    • 2012
  • In order to evaluate the efficacy of SHT against atopic dermatitis (AD), various immune related cytokines as well as histological comparison were performed in animal models, and the results are described. Clinical skin index of the SHT treated group decreased significantly in weeks 11 and 13, compared to the control group. Also, CD4+ immune cell ratio in the dorsal skin was significantly decreased to 69%, and both epidermal and dermal skin thickness was decreased. Serum IL-4, IL-5, IL-6, IL-13, and TNF-${\alpha}$, which are all important markers of inflammation, were decreased to 64%, 44%, 87%, 48%, and 45%, respectively. The expression of histamine, a chemical transmitter increasingly released during the progression of inflammation, was significantly decreased to 47%. The production of IgE immunoglobulin was significantly decreased to 16% compared to the control group. In conclusion, SHT pacifies the activation of T cells, leading to suppression of both Th2 cytokine overexpression and infiltration of immune cells into skin. As a result, relative thinning of both epidermis and dermis were observed. With the results obtained from in vitro studies, the immune modulatory effect of SHT in AD animal models was experimentally demonstrated. This study should provide solid information to construct EBM and for clinical practice.

A study on anti-thrombotic activity of Hwao-tang

  • Park Tae Woo;Park Won Hwan
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.1
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    • pp.181-185
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    • 2002
  • The thrombosis is the category of blood stasis. Blood stasis is a pathologicial state resulting from the reverse or impeded flow of blood in the body or the stagnation of blood flow in local parts as well as abnormal blood outside of the vessles which remains in the body and fails to disperse. Hwao-tang has been reported to have a hypolipidemic effect in patients with hypercholesterolemia, and in highcholesterol-induced experimental models. The present paper reports the effects of HOT on atherosclerosis using a spontaneous experimental model, Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbits. We have also investigated the pharmacological effect of extracts obtained from HOT on collagen-and ADP-induced blood platelet aggregation, thrombin-induced conversion of fibrinogen and fibrinolysis in in vitro experiments. In conclusion, the protection of extracts of Korean herbs' HOT on the ischemic infarction induced artificially might be involved to their inhibition of thrombotic action.

Current Researches on Vocal Fold Aging (노인성 음성에 대한 최신 연구동향)

  • Lim, Jae-Yol
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.25 no.1
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    • pp.24-26
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    • 2014
  • Aging causes a variety of changes in the structure of the vocal fold (VF), resulting in aging-induced dysphonia (presbyphonia). Several studies have investigated the structure of the VF of elderly people from autopsy as well as animal studies. There is an increasing evidence on correlation of structural changes of VF with deteriorated voice in elderly. Although the cellular mechanisms of aging VF have only partially been elucidated, there are many recent advances in biological treatment on aging VF using bioactive molecules such as growth factors. In this study, I'd like to address aging-related structural, biological, and physiological changes in previous literature about human and rodent aging VFs, to provide further insight into the mechanisms responsible for presbyphonia and to translate the basic researches for future clinical trials.

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NEAR INFRARED BIO-SPECTROSCOPY : APPROACHES FOR MEASUREMENTS IN CRITICAL CARE

  • Burns, David
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.2102-2102
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    • 2001
  • Near infrared, diffuse reflectance spectroscopy has shown significant potential for in vitro and in vivo assessment of metabolic status. However, the complexity of living samples can lead to ambiguous results. This presentation will focus on methods that provide controls for scattering and absorption estimation in tissue. For robust estimations, normalization procedures will be shown which can greatly improve interpretability of results. Normalization based on time, location and spectral property will be shown with data from models, tissue phantoms and in vivo measurements. In particular, interpretation of NIR spectra associated with major respiratory constituents will be examined. Measurement of constituents such as hemoglobin, myoglobin, tissue edema, and lactate will be shown. Results suggest that NIR may provide a valuable tool for physiological monitoring in critical care research and practice.

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Metabotropic Glutamate Receptor and Anxiety (Metabotropic Glutamate 수용체와 불안)

  • Park, Young-Min;Yi, Hyeon-Lyung;Lee, Seung-Hwan
    • Anxiety and mood
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    • v.3 no.1
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    • pp.8-14
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    • 2007
  • Although treatments of anxiety symptom have been available for decades, the biological basis for anxiety disorders in humans is just beginning to emerge. Recently, there is a growing body of literature suggesting that group II metabotrpic glutamate (mGlu) receptors and group I mGlu receptors are important in the physiological and behavioral sequelae associated with stressful stimuli. Moreover, compounds selective for mGlu receptors, particularly mGlu2/3 and/or mGlu5, have proven as effective as classical anxiolytics in various animal models of anxiety without producing many of the unwanted side effects that are typical of current therapies. This article will focus on the emerging preclinical and clinical data that implicate modulation of the mGlu receptors as a potential anxiolytic strategy.

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On the Forming Processes of Soil Humic Substances and its Physiological Effects on Plants (토양(土壤) 부식물(腐植物)의 생성(生成)과 효과(効果)에 대(對)한 고찰(考察))

  • Lim, Sun-Uk
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.1
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    • pp.67-73
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    • 1973
  • Soil humic substances are defined as a humified part of the soil organic matters and regarded to play beneficial roles for colloid chemical properties and the fertility of the soils. This paper is referred to review the present trend of the studies on the forming processes of humic substances and on the effect on plant metabolism by some organic compounds that are directly absorbed by plants. It is generally considered that the humic substances are formed organic matters in soil or plant materials through numerous organic or biochemical processes. However, the nature of the constituting "core" and of attachment of carbohydrate, nitrogen containing compounds like protein, phenolic compounds and metals to the core are unclear though various models are suggested. It is reviewed that some organic compounds, phenclic acids, derived from humic substances are effective on plant metablism in many cases, although the mechanisms are remained to be clarified.

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