• Journal of Community Nutrition
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• v.4 no.3
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• pp.195-201
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• 2002

The purpose of this study was to examine the effects of dietary calcium supplementation and exercise on bone mineral density and bone mineral content of growing female rats. The exercise and control group were fed a diet containing 0.5% calcium and Ca supplementation group were fed a diet containing 1.0% calcium diet. The exercise group ran on a rodent treadmill (speed of 15m/min for 30 min) three days per week during the 3-week study period. Bone mineral density (BMD) and bone mineral content (BMC) of spine and femur were determined by using dual energy x-ray absorptiometry (FIXI-mus, GE Lunar Radiation Cooperation, Madison, WI, USA). The exercise group had significantly greater (6.25%) spine BMD compared to the nonexercise group and the exercise group had but not significantly greater spine BMC (7.1%) compared to nonexercisers. Femur BMD and BMC divided by the rats final body weight appears to have a higher BMD (7.5%) and BMC (4.5%) in the exercise group, which indicates that exercise had a positive influence on femur bone mineral density and bone mineral content. The supplementation of calcium did not significantly affect spine and femoral BMC and BMD for the 3 weeks experimental period. It can be concluded that when calcium intake meets the recommended, exercise is beneficial for acquisition of spine bone mineral density in young growing female rats. (J Community Nutrition 4(3) : 195∼201, 2002)

• Proceedings of the Korean Society of Developmental Biology Conference
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• 1998.07a
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• pp.50-51
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• 1998

guanidinoacetate methyltransferase (GAMT) catalyzes the last step of creatine biosynthesis in mammals. Creatine plays an important role in cellular energy metabolism in variety of tissues including brain and male reproductive tract. Congenital deficiency of the enzyme leads to a neurologic disorder in humans. We used an interspecific backcross DNA panel to map Gamt to the central region of mouse Chromosome (Chr) 10 near the locus of hesitant mutation affecting male fertility. We assigned the human GAMT gene to Chr 19 by PCR analysis of a human/rodent somatic hybrid cell line DNA panel, and further localized the human gene to Chr 19 at band p13.3 by PCR analysis of a human radiation hybrid DNA panel. Human chr 19p13.3 is homologous to the central part of mouse Chr 10 where mouse Gamt is located. Furthermore, this part of mouse Chr 10 contains mutant loci the phenotype of which is similar to the GAMT deficiency in human.

• Korean Journal of Animal Reproduction
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• v.26 no.4
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• pp.321-328
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• 2002

The hormone resistin is associated with type II diabetes mellitus in rodent model. Resistin impairs glucose tolerance and insulin action. A new class of anti-diabetic drugs were called thiazolidinediones (TZDs) downreguates a resistin. Resistin gene expression is induced during adipocyte differentiation and resistin polypeptide is secreted by adipocytes. But, the correlation between increased adiposity and resistin remains unknown. The objectives of this study was to clone a mouse resistin CDNA and to generate transgenic mice overexpressing mouse resistin gene. The pCMV-mus/resistin gene was prepared from previous recombinant pTargeT$^{TM}$-mus/resistin by digestion of Bgl II, and has used for microin- jection into pronuclei of one cell embryos. Mouse resistin expression was detected in transgenic F$_1$mice by RT-PCR. The transgenic mouse with resistin gene expression has heavier body weight which was measured higher level of plasma glucose than that of normal mouse. And in diet-induced experiments, in fasting group, resistin expression was higher than that of re-feeding group. This result demonstrates that the resistin gene overexpressing mice may be became to obesity and be useful as an animal disease model to be diabetes caused by insulin resistance of resistin.n.

• Journal of Veterinary Clinics
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• v.18 no.4
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• pp.358-362
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• 2001

Brain dead (BD) patients remain the largest source of solid organs for transplantation. BD has shown to decrease graft function and survival in rodent models. The aim of this study was to evaluate how brain death affects graft viability in the donor and kidney tolerance to cold preservation as assessed by survival in a canine transplantation. 13 Beagle dogs were used for the study. Brain death was induced by the sudden inflation of a subdural balloon catheter with continuous monitoring of arterial blood pressure and eletroencephalographic activity (n=3). Sixteen hours after conformation of brain death, kidney graft were retrieved (n=6). Non-BD donors served as controls (n=4). All kidneys were flushed with University of Wisconsin (UW) solution and preserved for 24 hours at 4$^{\circ}C$ before transplantation. Recipient survival rates, serum creatinine level were analyzed. Brain death induced the well-known Cushing reaction with a severe increase in blood pressure and tachycardia. Thereafter, cardiac function returned progressively to baseline within 8 hours and remained stable until the end of the experiment. All of dogs in both group transplanted were survived until 7 days (100%), and the kidneys showed functional early rejection at 8.3$\pm$0.5 days and 8.5$\pm$0.5 days after transplantation, in BD and allograft group, respectively. BD kidneys were functionally similar to control kidneys for 7 days after transplantated. Brain death has no deleterious effect on preservation injury and survival of dog kidney transplantation, although it induces changes in hemodynamic parameters. This study reveals that kidneys from BD donors do not exhibit more ischemia reperfusion injury, and support good early function and survival.

• Toxicological Research
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• v.22 no.4
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• pp.423-429
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• 2006

Recent reports on the photocarcinogenicity and photogerotoxicity of many compounds led to an increasing awareness for the need of a standard approach to test for photogenotoxicity. The comet assay has been recently validated as a sensitive and specific test system for the quantification of DNA damage. Thus, the objectives of this study are to investigate the utility of photo-comet assay for detecting photo-mutagens, and to evaluate its ability to predict rodent photo-carcinogenicity. Photo-comet assays were performed using L5178Y $Tk^{+/-}$ mouse lymphoma cells on five test substances (8-methoxypsoralen, chlorpromazine, lomefloxacin, anthracene and retinoic acid) that demonstrated positive results in photocarcinogenicity tests. For the best discrimination between the test substance-mediated DNA damage and the undesirable DNA damage caused by direct UV absorption, a UV dose-response of the cells in the absence of the test substances was firstly fnalized. Out of 5 test substances, positive comet results were obtained for chlorpromazine, lomefloxacin, anthracene and retinoic acid while 8-methoxypsoralen found negative. An investigation into the predictive value of this photo-comet assay for determining the photocarcinogenicity showed that photo-comet assay has relatively high sensitivity. Therefore, the photo-comet assay with mammalian cells seems to be a good and sensitive predictor of the photocarcinogenic potential of new substances.

• Biomolecules & Therapeutics
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• v.8 no.2
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• pp.147-152
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• 2000

The rodent uterotrophic assay is currently recommended as one of the primary in vivo assays far endocrine disrupting chemicals by the Organization for Economic Cooperation and Development (OECD) and Endocrine Disruptor Screening and Testing Advisory Committee (US EPA EDSTAC). Generally, this assay relies on the rapid increase in uterus and vagina weights when exposed to estrogenic compounds. Phthalate esters have been used extensively as a plasticizer in the manufacture of plastic products such as PVC films and medical devices. Recently, phthalate esters have been shown to induce endocrine system mediated responses. However, a flew studies have been conducted for the screening of their estrogenic activity. In this study the estrogenic activity of seven phthalate esters, butyl benzyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), di-n-butylphthalate (DBP), diethylphthalate (DEP), di-n-pentylphthalate (DPF), di-n-propylphthalate (DPrP) and dicyclohexylphthalate (DCHP), was examined in uterotrophic assay. Phthalate esters dissolved in corn oil were administered to ovariectomized (OVX) female Sprague-Dawley rats by sub-cutaneous injection for three consecutive days. fiats were sacrificed 24h after final treatment, and then uterus and vagina weights were deter mined. All phthalate esters tested in this assay did not change talc uterus and vagina weights at dosage levels up to 200 mg/kg/day treatment. These results demonstrated that phthalate esters did not exhibit estrogenic activity in vivo uterotrophic assay.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.63-67
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• 2014

This paper describes a new species of chigger mite (Acari: Trombiculidae), Gahrliepia cangshanensis n. sp., from rodents in southwest China. The specimens were collected from Yunnan red-backed voles, Eothenomys miletus (Thomas, 1914), and a Chinese white-bellied rat, Niviventer confucianus (Milne-Edwards, 1871) in Yunnan Province. The new species is unique mainly in its number of dorsal setae (n=21), and it has the following features: fT (formula of palpotarsus)=4B (B=branched), fp (formula of palpal seta)=B/N/N/N/B (N=naked), a broad tongue-shaped scutum with an almost straight posterior margin, and 17 PPLs (posterior posterolateral seta) with a length of 36-43 ${\mu}m$. This chigger mite may also infect other rodent hosts and may be distributed in other localities.

• Animal Systematics, Evolution and Diversity
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• v.30 no.3
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• pp.159-175
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• 2014

A taxonomic study of small mammals (Erinaceomorpha, Soricomorpha and Rodentia) was conducted in order to find out the scientific names which have been used in Korea. The synonymy of each species and taxonomical research was reviewed and confirmed in this study. The species names are rearranged based on recent studies. Among the various confused names, available names were adopted such as follows: C. shantungensis shantungensis known as Crocidura suaveolens; C. shantungensis quelpartis known as C. dsinezumi; Rattus tanezumi known as R. rattus, called black rat, roof rat and ship rat, respectively. Apodemus sylvaticus (Muridae, wood mouse) is excluded in the checklist based on indistinct previous records and ambiguous habitation on the Korean Peninsula, and neighbors. In addition, we provide a new Korean vernacular name for Myocastor coypus, called the "Nutria" in Korea. We reflect that several species are repositioned to other genera. A checklist of Korean small mammals and synonym list for each species is provided to avoid confusion of scientific names in Korea. In this study, the list of small mammals in Korea is arranged to 33 species, 20 genera, 8 families, and 3 orders.

• Toxicological Research
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• v.32 no.1
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• pp.21-33
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• 2016

Dichlorodiphenyltrichloroethane (DDT) is still used in certain areas of tropics and subtropics to control malaria and other insect-transmitted diseases. DDT and its metabolites have been extensively studied for their toxicity and carcinogenicity in animals and humans and shown to have an endocrine disrupting potential affecting reproductive system although the effects may vary among animal species in correlation with exposure levels. Epidemiologic studies revealed either positive or negative associations between exposure to DDT and tumor development, but there has been no clear evidence that DDT causes cancer in humans. In experimental animals, tumor induction by DDT has been shown in the liver, lung, and adrenals. The mechanisms of hepatic tumor development by DDT have been studied in rats and mice. DDT is known as a non-genotoxic hepatocarcinogen and has been shown to induce microsomal enzymes through activation of constitutive androstane receptor (CAR) and to inhibit gap junctional intercellular communication (GJIC) in the rodent liver. The results from our previously conducted 4-week and 2-year feeding studies of p,p'-DDT in F344 rats indicate that DDT may induce hepatocellular eosinophilic foci as a result of oxidative DNA damage and leads them to hepatic neoplasia in combination with its mitogenic activity and inhibitory effect on GJIC. Oxidative stress could be a key factor in hepatocarcinogenesis by DDT.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.38-40
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• 1995

There have reports suggested that cerebral blood flow (CBF) has decreased in patients with both senile dementia of the Alzheimer's type and multi-infarct dementia, which are characterized by marked cognitive impairments. In addition, recent studies have demonstrated that decrease of CBF precedes the onset of multi-infarct dementia. These findings further suggest that chronic reduction of CBF may play an important role in the formation and progression of cerebral vascular dementia. Although transient cerebral ischemia, based upon vascular “reperfusion”, is apparently not paralleling the clinical condition, the transient cerebral ischemia model is one of the major methods investigated and the other is the cerebral embolism operation. Cognitive impairment and neuronal damages have been fully studied using these transient and/or embolic ischemia models. There are, however, few investigations focused the attention on the influence of chronic decrease of CBF on cognitive processes. In the present study, we have chosen a chronic ischemic model which is produced by permanent occlusion of bilateral common carotid arteries (2VO) in rats to investigate the neuronal damage and cognitive deficits through radial maze performance. We investigated furtherly the effects of tetramethylpyrazine (TMP), a constituent isolated from Ligusticum Chuanxiong on such a model.