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Neuroendocrine Control of Gonadotropin Secretion during the Menstrual Cycle

  • Ryu, Kyung-Za
    • The Korean Journal of Pharmacology
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    • v.23 no.2
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    • pp.57-75
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    • 1987
  • Two modalities of gonadotropin secretion, pulsatile gonadotropin and preovulatory gonadotropin surge, have been identified in the mammals. Pulsatile gonadotropin secretion is modulated by the pulsatile pattern of GnRH release and complex ovarian steroid feedback actions. The neural mechansim that regulates the pulsatile release of GnRH in the hypothalamus is called "GnRH pulse generator". Ovarian steroids, estradiol and progesterone, appear to exert thier feedback effects both directly on the pituitary to modulate gonadotropin release and on a hypothalamic site to modulate GnRH release; estradiol primarily affects the amplitude while progesterone decreases the frequency of the pulsatile GnRH. Steroid hormones are known to affect catecholamine transmission in brain. MBH-POA is richly innervated by NE systems and close apposition of NE terminals and GnRH cell bodies occurs in the MBH as well as in the POA. NE normally facilitates pulsatile LH release by acting through ${\alpha}-receptor$ mechanism. However, precise nature of facilitative role of NE transmission in maintaining pulsatile LH has not been clearly understood. Close apposition of DA and GnRH terminals in ME might permit DA to influence GnRH release. Action of DA transmission probably is mediated by axo-axonic contacts between GnRH and DA fibers in the ME. Dopamine transmission does not normally regulate pulsatile LH release, but under certain conditions, increased DA transmission inhibit LH pulse. Endogenous opioid acts to suppress the secretion of GnRH into hypophysial portal circulation, thereby inhibiting gonadotropin secretion. However, an interaction between endogenenous opioid peptides and gonadotropin release is a complex one which involves ovarian hormones as well. LH secretion appears to be most suppressed by endogenenous opioids during the luteal phase, at a time of elevated progesterone secretion. The arcuate nucleus contains not only cell bodies for GnRH and ${\beta}-endorphin$ but also a dense aborization of fibers suggesting that GnRH release is changed by the interactions between GnRH and ${\beta}-endorphin$ cell bodies within the arcuate nucleus. The frequency and amplitude of pulsatile LH release seem to be increased during the preovulatory gonadotropin surge. Estradiol exerts positive feedback action on the hypothalamo-pituitary axis to trigger preovulatory LH surge. GnRH is also crucial hormonal stimulus for preovulatory LH surge. It is unlikely, however, that increased secretion of GnRH during the preovulatory gonadotropin surge represents an obligatory neural signal for generation of the LH discharge in primates including human. Modulation of preovulatory LH surge by catecholamines has been studied almost exclusively in rats. NE and E may be involved in distinct way to accumulate GnRH in the MBH and its release into the hypophysial portal system during the critical period for LH surge on proestrus in rats. However, the mechanisms whereby augmented adrenergic transmission may facilitate the formation and accumulation of GnRH in the ME-ARC nerve terminals before the LH surge have not been clearly understood.

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Source Proximity and Meteorological Effects on Residential Ambient Concentrations of PM2.5, Organic Carbon, Elemental Carbon, and p-PAHs in Houston and Los Angeles, USA

  • Kwon, Jaymin;Weisel, Clifford P.;Morandi, Maria T.;Stock, Thomas H.;Turpin, Barbara
    • Journal of Environmental Science International
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    • v.25 no.10
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    • pp.1349-1368
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    • 2016
  • Concentrations of fine particulate matter ($PM_{2.5}$) and several of its particle constituents measured outside homes in Houston, Texas, and Los Angeles, California, were characterized using multiple regression analysis with proximity to point and mobile sources and meteorological factors as the independent variables. $PM_{2.5}$ mass and the concentrations of organic carbon (OC), elemental carbon (EC), benzo-[a]-pyrene (BaP), perylene (Per), benzo-[g,h,i]-perylene (BghiP), and coronene (Cor) were examined. Negative associations of wind speed with concentrations demonstrated the effect of dilution by high wind speed. Atmospheric stability increase was associated with concentration increase. Petrochemical source proximity was included in the EC model in Houston. Area source proximity was not selected for any of the $PM_{2.5}$ constituents' regression models. When the median values of the meteorological factors were used and the proximity to sources varied, the air concentrations calculated using the models for the eleven $PM_{2.5}$ constituents outside the homes closest to influential highways were 1.5-15.8 fold higher than those outside homes furthest from the highway emission sources. When the median distance to the sources was used in the models, the concentrations of the $PM_{2.5}$ constituents varied 2 to 82 fold, as the meteorological conditions varied over the observed range. We found different relationships between the two urban areas, illustrating the unique nature of urban sources and suggesting that localized sources need to be evaluated carefully to understand their potential contributions to $PM_{2.5}$ mass and its particle constituents concentrations near residences, which influence baseline indoor air concentrations and personal exposures. The results of this study could assist in the appropriate design of monitoring networks for community-level sampling and help improve the accuracy of exposure models linking emission sources with estimated pollutant concentrations at the residential level.

A Study on Health Risk Assessment by Exposure to Organic Compounds in University Laboratory (대학 실험실에서의 유기화합물 노출에 의한 건강위험성 평가에 관한 연구)

  • Sim, Sanghyo;Won, Jung-II;Jeon, Hasub;Kim, Dowon
    • The Journal of Korean Society for School & Community Health Education
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    • v.22 no.4
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    • pp.49-60
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    • 2021
  • Objectives: Laboratories have various latent physical, chemical, biological, and ergonomical factors according to the diversification and fusion of research and development activities. This study aims to investigate the chemical exposure concentrations of college laboratories and evaluate their health risks, and use them as basic data to promote the health of college students. Methods: The sampling and analysis of harmful chemicals in the air in laboratories were performed using Method 1500 of the U.S. National Institute for Occupational Safety and Health (NIOSH)의 Method 1500. The harmful chemicals in the laboratories were divided into carcinogenic and non-carcinogenic chemicals. Risk assessment was performed using the cancer risk (CR) for carcinogenic chemicals and using the hazard index (HI) for non-carcinogenic chemicals. Results: The harmful chemicals in college laboratories consisted of acetone, diethyl ether, methylene chloride, n-hexane, ethyl acetate, chloroform, tetrahydrofuran, toluene, and xylenes. They showed the highest concentrations in laboratories A (acetone 0.001~2.34ppm), B (chloroform 0.95~6.35ppm), C (diethyl ether 0.08~8.68ppm), and D (acetone 0.07~14.96ppm). The risk assessment result for non-carcinogenic chemicals showed that the HI of methylene chloride was 2.052 for men and 2.333 for women, the HI of N-hexane was 4.442 for men and 5.05 for women. Thus, the HI values were higher than 1. The risk of carcinogenic chemicals is determined by an excess cancer risk (ECR) value of 1.0×10-5, which means that one in 100,000 people has a cancer risk. The ECRs of chloroform exceeded 1.0×10-5 for both men and women, indicating the possibility of cancer risk. Conclusion: College laboratories showed the possibility of non-carcinogenic health risks for methylene chloride, n-hexane, tetrahydrofuran (THF), toluene, and xylenes, and carcinogenic health risks for chloroform, methylene chloride. However, this study used the maximum values of measurements to determine the worst case, and assumed that the subjects were exposed to the corresponding concentrations continuously for 8 hours per day for 300 days per year. In consideration of the nature of laboratory environment in which people are intermittently exposed, rather than continuously, to the chemicals, the results of this study has an element of overestimation.

Earth Construction Interior Applied to Healing Space : Focused on Biophilic Design Concept of Oriental Medical Clinic Interior (치유공간에 적용한 흙건축 인테리어 -한의원인테리어의 바이오필릭(Biophilic)디자인개념을 중심으로-)

  • Jeon, Chan Hee;Hwang, Hey Zoo
    • Journal of the Korean Society of Floral Art and Design
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    • no.42
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    • pp.37-62
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    • 2020
  • The earth is a natural material that has natural healing power,,as a natural ingredient, it brings environmental friendliness, emotional. In this Research, for one of the methods to expand the benefits as a healing space, Construction of the Earth design and earth construction methods have been actively used for effectiveness of the Earth in the construction of the interior with the oriental medical clinic. By utilizing the concept of biophilic design as a healing environment design, symbolizing nature such as color, light, plants, flowers, and natural materials such as earth and wood was directed as oriental medicine interiors. In addition, the space was divided according to the movement of patients and used different Earth construction method to each of the space for the distinction and differentiation according to the characteristics of each space. At this time, the Earth was constructed with materials and finishing materials that meet the highest grade of HB (Healthy Building), an eco-friendly building material certification grade without additives, so that the interior and medical treatment concept can be done at the same time. By using Earth as the basis of elements in the construction, and the design of healing space, patient the concept of Biophillic as a healing environment design. This may serve as a technical, aesthetic, and cultural basis for constructing a healing space by Earth in the future-oriented alternative, it may lead to necessity of eco-friendly and ecological architecture, and it may be an opportunity to expand the application area of earth in architectural design.

In vitro culture of adventitious root from Rhodiola sachalinensis (기내배양을 통한 홍경천(Rhodiola sachalinensis)의 부정근 생산)

  • Bae, Kee-Hwa;Yoon, Eui-Soo;Choi, Yong-Eui
    • Korean Journal of Plant Resources
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    • v.22 no.4
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    • pp.281-286
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    • 2009
  • Rhodiola sachalinensis is one of the most popular oriental medicines in East Asia. It is a perennial herb, belonging to the family Crassulaceae, which is mainly distributed in mountains at the altitudes of 1700-2500 m in Baek-Du mountain. Cultivation of this species for the production of medicine materials is not easy in nature, because of restrict habitats. In vitro production of roots can be applicable for the production of medicinal materials. Here, we investigated the optimal conditions for induction and proliferation of adventitious roots in in vitro culture system. Leaf, stem and root segments from R. sachalinensis were cultured on Murashige and Skoog(MS) medium supplemented with the various concentrations of IBA(Indole-3-butyric acid)(0.5, 1.0, 3.0, and 5.0 mg/L) and sucrose(10, 30, 50, and 100 g/L). The optimal explant for adventitious root induction was leaf segment. Induction of adventitious roots was highest on MS medium supplemented with 5.0 mg/L IBA and sucrose 30 g/L. In liquid culture, fresh weight of adventitious roots was highest(15.65 g) on 1/3 strength MS liquid medium supplemented with 5.0 mg/L IBA with 30 g/L sucrose. These results revealed the first attempt for the production of adventitious roots in R. sachalinensis.

Recent Advances in Cancer Diagnosis: On an Overview of Diagnostic Cytopathologic Modalities and Ancillary Techniques (세포병리학적 기초에 의한 암진단의 발전: 진단방법과 보조기법)

  • Kim, Ki-Tai;Ham, Eui-Keun
    • The Korean Journal of Cytopathology
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    • v.7 no.1
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    • pp.1-11
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    • 1996
  • From the concepts of cellular pathology and of exfoliative cytology, as elucidated by Virchow and Papanicolaou respectively in the late 19th and early 20th century, have evolved the primary methods for the diagnosis of cancer today. From Papanicolaou's concept of exfoliative cytology developed fine needle aspiration biopsy in the early 1960's, this has become a major diagnostic procedure and has contributed to a significant reduction in open biopsies and, therefore, to medical cost-effectiveness immunobiochemical techniques provided us with a supplement to cancer diagnosis in the 1980's. The immunoperoxidase method, using monoclonal antibodies, is applied primarily as an ancillary measure to elucidate the nature of cancers The availability of specific monoclonal antibodies has greatly facilitated the identification of cell products or surface markers. For example, antibodies directed against intermediate filaments have proved to be of value in determining the histogenesis oi poorly differentiated neoplasms. Tumor markers may serve as biochemical indicators of the presence of a neoplasm. They can be detected In plasma and other body fluids. Their concentration can be applied as a diagnostic test, for monitoring the clinical course of known cancer, and as a screening measure to detect certain cancers in a population at risk. Flow cytometry is a useful tool for distinguishing several cell characteristics, such as the immunophenotype of leukemia-lymphoma cells, the DNA content of neoplastic cells, and cell proliferation rate. Molecular biologic techniques provided a giant step for the management of cancer patients encompassing diagnosis, prognostic evaluation, and therapy. Nucleic acid hybridization techniques are utilized as Southern, Northern, and dot blots and in situ hybridization. Molecular biology and its techniques may bring a blight new horizon for understanding cancer biology and in designing therapy on the basis of gene manipulation.

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Effect of Bu-Zhong-Yi-Qi-Tang on B Cell Development (보중익기탕(補中益氣湯)의 B세포 분화 유도 효과)

  • 신성해;채수연;하미혜;조성기;김성호;변명우;이성태
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.2
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    • pp.271-277
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    • 2004
  • This study was designed to evaluate the effect of Bu -Zhong-Yi-Qi-Tang extracts, a prescription of traditional oriental medicine, on development of the B cells. In the bone marrow cell cultures, progenitors viability, expressions of particular cell- surface proteins and production of immunoglobulins were investigated in the presence of Bu-Zhong-Yi-Qi-Tang extracts. The administration of Bu-Zhong -Yi-Qi-Tang polysaccharide fraction increased the viable cell numbers of the precursor B cells, and elevated expression levels of CD19/CD40 specific for pre-B cells after 10 days culture were demonstrated by flow cytometry analysis. The production of immunoglobulin M in the presence of polysaccharide fraction increased progressively in the culture supernatant, and preferentially induced class switching to IgG1, IgG2a and IgG3. These results indicated that Bu -Zhong -Yi-Qi -Tang strong1y correlated with the development of precursor B cells in the bone marrow cell culture. Therefore the polysaccharide fraction of Bu-Zhong-Yi -Qi-Tang might be a useful radioprotector, especially since it is a relatively non-toxic natural product. Further studies are needed to better characterize the protective nature of Bu-Zhong-Yi -Qi -Tang extract.

Effect of Bu-Zhong-Yi-Qi-Tang on Proliferation of T Cells (보중익기탕의 T세포 증식 유도 효과)

  • 채수연;신성해;하미혜;조성기;김성호;변명우;이성태
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.7
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    • pp.1085-1091
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    • 2004
  • Bu-Zhong-Yi-Qi- Tang extracts is a traditional oriental medicine in a mixture type exhibiting strong anti-bacterial, analgesic, and chemopreventive activities. In this study, we have evaluated effects of the total and polysaccharide fraction of Bu-Zhong-Yi-Qi- Tang extracts on the T cell proliferation, cytokine production, and induction of IL-2 receptor and MHC class n. For this experiment, we established CD4$^{+}$ CD8$^{[-10]}$ T cell line producing IL-2 and IFN-${\gamma}$ when stimulated with ovalbumin antigen in the presence of antigen presenting cells. The significant effect of Bu-Zhong-Yi-Qi-Tang on antigen-induced T cell proliferation in the presence of antigen presenting cells was observed. The proliferation and IFN-${\gamma}$ production of T cells was increased in a dose dependent manner, and expression of IL-2 receptor on T cells and MHC class n molecule on antigen presenting cells was also induced in the presence of Bu-Zhong-Yi-Qi-Tang polysaccharide fraction. It was demonstrated that polysaccharide fraction of Bu-Zhong-Yi-Qi-Tang stimulates the antigen-induced T cell proliferation and the production of IFN-${\gamma}$ possibly through the increase of IL-2 receptor and MHC class n expression. Therefore Bu-Zhong-Yi-Qi-Tang can be regarded as a natural and useful immunomodulator having a relatively nonotoxic property. Further studies are needed to better characterize the nature of Bu-Zhong- Yi-Qi-Tang extract.

An Analysis of the Trends of Aromatherapy Researches in Chinese Literatures

  • Sun, Jiao-Jing;Kim, Kyeong-Ran
    • Journal of the Korea Society of Computer and Information
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    • v.26 no.1
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    • pp.239-251
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    • 2021
  • Traditional Chinese medicine has treated diseases and improved health in nature-based experience. Advanced nations began to be interested in naturopathic therapy in the late 19th century and it led China to research aromatherapy. This study searched previous researches related with aromatherapy and generally analyzed aroma oil, applied body parts, methods of use, and period of use. For research contents, scientific and society journals from 2000 to 2019 related with aromatherapy were searched in CNKI(www.cnki.com) and WANFANG DATE(www.wanfang.com). Finally, 30 papers were selected through 5-step qualitative evaluation and expert review and analyzed. Frequency and percentage(%) were calculated by means of the Excel 2013 Program and represented by a chart. The results of analyzing aromatherapy trends are as follows. All 30 papers were researched in the medical society. The most common symptom was irritation and anxiety that appeared in 13 papers. Lavender oil and bergamot oil were commonly used aroma oil. Commonly applied part and method were nose and nasal inhalation. For aroma oil associated with symptoms, lavender oil was the best in irritative, anxious, and negative emotion, depression, labor pain, sleep disorder, migraine, tension, and vomiting, pain, and fatigue after operation. Lemon, ginger, and peppermint oil was good for nausea. Based on the findings, this study derived applied body parts, methods of use, and period of use in aromatherapy. However, most aromatherapy was used for patients in the nursing and medical fields in the simple form of inhalation and local massage. This study will suggest a standard ground that aromatherapy is good for pain, colic pain, and tension in a short period but needs a long period for the efficacy of psychological and neurological symptoms.

Classification of Magnetic Resonance Imagery Using Deterministic Relaxation of Neural Network (신경망의 결정론적 이완에 의한 자기공명영상 분류)

  • 전준철;민경필;권수일
    • Investigative Magnetic Resonance Imaging
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    • v.6 no.2
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    • pp.137-146
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    • 2002
  • Purpose : This paper introduces an improved classification approach which adopts a deterministic relaxation method and an agglomerative clustering technique for the classification of MRI using neural network. The proposed approach can solve the problems of convergency to local optima and computational burden caused by a large number of input patterns when a neural network is used for image classification. Materials and methods : Application of Hopfield neural network has been solving various optimization problems. However, major problem of mapping an image classification problem into a neural network is that network is opt to converge to local optima and its convergency toward the global solution with a standard stochastic relaxation spends much time. Therefore, to avoid local solutions and to achieve fast convergency toward a global optimization, we adopt MFA to a Hopfield network during the classification. MFA replaces the stochastic nature of simulated annealing method with a set of deterministic update rules that act on the average value of the variable. By minimizing averages, it is possible to converge to an equilibrium state considerably faster than standard simulated annealing method. Moreover, the proposed agglomerative clustering algorithm which determines the underlying clusters of the image provides initial input values of Hopfield neural network. Results : The proposed approach which uses agglomerative clustering and deterministic relaxation approach resolves the problem of local optimization and achieves fast convergency toward a global optimization when a neural network is used for MRI classification. Conclusion : In this paper, we introduce a new paradigm to classify MRI using clustering analysis and deterministic relaxation for neural network to improve the classification results.

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