• Journal of Environmental Impact Assessment
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• v.7 no.1
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• pp.23-34
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• 1998

This study was carried out to survey the fauna of some parks around Kunsan-city and to establish biological impact on the development of those parks. Among the fauna surveyed, insects consist of 74 species in 49 families and 13 orders. The insect fauna was poor, because the environment was made of simple flora and mostly farmland. Fish in the reservoir of Wolmyong-Park consist of 7 species. Among them, Ctenopharyngodon idellus is an exotic species and characterized with its voracious plantfeeding. This fish severely destroyed the habitats and spawning sites of other sympatric fish. For the conservation of non-exotic fish, birds, and mammals in the area, the integrated biological direction would be needed.

• Development and Reproduction
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• v.16 no.4
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• pp.235-251
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• 2012

The reproductive activity in male mammals is well known to be regulated by the hypothalamus-pituitary-gonad axis. The hypothalamic neurons secreting gonadotropin releasing hormone (GnRH) govern the reproductive neuroendocrine system by integrating all the exogenous information impinging on themselves. The GnRH synthesized and released from the hypothalamus arrives at the anterior pituitary through the portal vessels, provoking the production of the gonadotropins(follicle-stimulating hormone (FSH) and luteinizing hormone (LH)) at the same time. The gonadotropins affect the gonads to promote spermatogenesis and to secret testosterone. Testosterone acts on the GnRH neurons by a feedback loop through the circulatory system, resulting in the balance of all the hormones by regulating reproductive activities. These hormones exert their effects by acting on their own receptors, which are included in the signal transduction pathways as well. Unexpected aberrants are arised during this course of action of each hormone. This review summarizes these abnormal phenomena, including various mutations of molecules and their actions related to the reproductive function.

• Biomedical Science Letters
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• v.11 no.4
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• pp.493-501
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• 2005

Circadian rhythms, time on a scale of about 24 hours, are present in a number of organisms including animals, plants, and bacteria. The control of the biochemical, physiological and behavioral processes is regulated by endogenous clocks in the suprachiasmatic nucleus (SCN). At the core of this timing mechanism is molecular machinery that are present both in the brain and in the peripheral tissues throughout the body, and even in a single cultured cell. In this study, we performed two-dimensional gel electrophoresis to figure out any correlation between protein expression patterns and the requirement of two canonical clock proteins, either mPER1 or mPER2, by comparing global protein expression profiles in livers from wildtype or mPer1/mPer2 double mutant mice. We could identify several differentially expressed protein candidates with respect to time and genotypes. Further analysis of these candidate proteins in detail in vivo will lead us to the better understanding of how circadian clock functions in mammals.

• The Journal of Korean Physical Therapy
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• v.15 no.2
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• pp.100-110
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• 2003

The purpose of this article is to understand of the muscle adaptation based on myosin heavy chain. Especially, skeletal muscle dadptation in related to aging, unloading, training will discussed. MHC expression is highly plastic in muscles of adult mammals in accordance with the environmental conditions. These changes is called muscle plasticity. The plasticity is the atility of muscle cell to alter either the quantity of protein or the type of protein. MHC is both an important structural and regulatory protein comprising the contractile apparatus.

• Parasites, Hosts and Diseases
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• v.27 no.4
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• pp.249-252
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• 1989

Fibricola cratera is a strigeoid trematode indigenous to North America that, heretofore, was known only to infect wild mammals. Herein, it is reported that an experimental inoculation of a human volunteer produced a patellt infection that lasted 40 months. Symptoms of epigastric discomfort, loose stools and flatulence occurred over the first year of infection and ameliorated thereafter. Eggs per gram of stool were low (${\leq}2$) throughout the course of infection and were not detected by the standard technique of formalin-ether concentration. To monitor infection, the entire stool sample was examined each month after sieving through No. 10 (pore size 2 mm) and 100 (pore size $145{\;}{\mu\textrm{m}}$) sieves and collecting eggs on a No. 325 (pore size $45{\;}{\mu\textrm{m}}$) sieve. This is the first report of a North American strigeoid trematode capable of maturing in a human and is only the second species of strigeoid known to do so. The other species is F. seoulensis which has been implicated in 26 human infections in Korea.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.809-816
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• 2010

Microbial biotransformations can be used to predict mammalian drug metabolism. The present investigation deals with microbial biotransformation of valdecoxib using microbial cultures. Thirty-nine bacterial, fungal, and yeast cultures were used to elucidate the biotransformation pathway of valdecoxib. A number of microorganisms metabolized valdecoxib to various levels to yield nine metabolites, which were identified by HPLC-DAD and LC-MS-MS analyses. HPLC analysis of biotransformed products indicated that a majority of the metabolites are more polar than the substrate valdecoxib. Basing on LC-MS-MS analysis, the major metabolite was identified as a hydroxymethyl metabolite of valdecoxib, whereas the remaining metabolites were produced by carboxylation, demethylation, ring hydroxylation, N-acetylation, or a combination of these reactions. The hydroxymethyl and carboxylic acid metabolites were known to be produced in metabolism by mammals. From the results, it can be concluded that microbial cultures, particularly fungi, can be used to predict mammalian drug metabolism.

• Interdisciplinary Bio Central
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• v.5 no.3
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• pp.6.1-6.7
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• 2013

Many insects such as mosquitoes cause life-threatening diseases such as malaria, yellow fever and West Nile virus. Malaria alone infects 500 million people annually and causes 1-3 million death per year. Volatile insect repellents, which are detected through the sense of smell, have long been used to protect humans against insect pests. Antifeed-ants are non-volatile aversive compounds that are detected through the sense of taste and prevent insects from feeding on plants. The molecular targets and signaling path-ways required for sensing insect repellents and antifeedants are poorly understood. Transient Receptor Potential (TRP) Ca2+-permeable cation channels exist in organisms ranging from C. elegans to D. melanogaster and Homo sapiens. Drosophila has 13 family members, which mainly function in sensory physiology such as vision, thermotaxis and chemotaxis. G protein-coupled receptors (GPCRs) initiate olfactory signaling cascades in mammals and in nematodes C.elegans. However, the mechanisms of G protein signaling cascades in insect chemosensation are controversial. In this review, I will discuss the putative roles of G protein-coupled receptors (GPCRs) and Transient Receptor Potential (TRP) channels as targets for insect repellents.

• Proceedings of the KSCN Conference
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• 2004.05a
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• pp.439.2-439
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• 2004

Melatonin in mammals, produced by the pineal gland and elsewhere, has shown antioxidant and neuroprotective properties in neuronal cells. We investigated whether melatonin would increase newly-born cells (cell proliferation) in the dentate gyrus of maternally-separated rats. To examine the effect of melatonin on cell proliferation of the dentate gyrus in maternally-separated rats, 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry was performed.(omitted)

• Development and Reproduction
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• v.15 no.3
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• pp.197-204
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• 2011

Egg activation is a crucial step that initiates embryo development upon breaking the meiotic arrest. In mammalian, egg activation is accomplished by fusion with sperm, which induces the repeated intracellular $Ca^{2+}$- increases ($[Ca^{2+}]_i$ oscillation). Researches in mammals support the view of the $[Ca^{2+}]_i$ oscillation and egg activation is triggered by a protein factor from sperm that causes $[Ca^{2+}]_i$ release from endoplasmic reticulum, intracellular $[Ca^{2+}]_i$ store, by persistently activation of phosphoinositide pathway. It represents that the sperm factor generates production of inositol trisphosphate ($IP_3$). Recently a sperm specific form of phospholipase C zeta, referred to as PLCZ was identified. In this paper, we confer the evidence that PLCZ represent the sperm factor that induces $[Ca^{2+}]_i$ oscillation and egg activation and discuss the correlation of PLCZ and infertility.

• Journal of Pharmaceutical Investigation
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• v.1 no.1
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• pp.34-46
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• 1971

The existence of oxytocin in the pituitary gland of chicken has been ascertained, but its physiological roles are still obscure. In the study the action of oxytocin on renal function of the chicken was investigated during water diuresis, utilizing clearance and the Sperber technique. The results obtained are summarized as follows: Oxytocin, like in many species of mammals, elicited a profound diuretic response in the chicken. Urine flow, excretion of electrolytes, as well as glomerular filteration rate increased, with intravenous infusion of $3{\sim}10\;m{\mu}/kg/min$. Oxtocin, infused into the renal portal circulation via hindleg vein in a dose of $3{\sim}13\;m{\mu}/kg/min$. elicited marked increase in urine flow, glomerular filteration rate and sodium excreted in the urine. The diuretic effect was more pronounced in the infused side. It is suggested that diuretic response to oxytocin in the chicken results from dual action of oxytocin: increase of GFR and inhibition of sodium reabsorption on the renal tubule. The possibility that oxytocin might act through some endogenous substances could be ruled out.