Researches on manipulating pluripotent stem cells derived from blastocysts or primordial germ cells (PGCs) have a great advantage for developing innovative technologies in various fields of life science including medicine, pharmaceutics, and biotechnology. Since their first isolation in the mouse embryos(1), stem cells or stem cell-like colonies have been continuously established in the mouse of different strains(21), cattle(2, 3), pig(4, 5), rabbit(6, 7), and human(9). However, full-term development originated from established pluripotent cells, which is an absolute criterion for proving cell pluripotency and differentiation, has only been reported in the mouse(22). Due to technical difficulties, no further progress has been made in the establishment of animal embryonic stem (ES) cell line. Alternatively, the use of embryonic germ (EG) cells was selected to establish an animal stem cell line. EG cells also have pluripotent characteristics, which were proven by morphological assay, intracellular alkaline phosphatase activity, and reactions with cell surface-specific markers. The finding of Labosky et al.(23) on germline chimera development after transfer to embryos clearly proved the pluripotency of EG cells and their similar characteristics with ES cells. Avian transgenesis has an unlimited value in biotechnology industry, since its applicability as a bioreactor has proven to be greater than that of mammalian species(24). In the chicken, EG cells can be extensively utilized instead of ES cells for efficiently inducing transgenesis mediated by germline transmission. Recently, PGCs collected from the embryonic gonad were suggested to be useful in establishing avian stem cells. Technical feasibility and applicability of gonadal PGCs (gPGCs) to germline chimera production were also confirmed(25) and a gPGC culture system to establish EG cells was subsequently developed(15).
Alkaline Phosphatase ; Animals* ; Biological Science Disciplines ; Bioreactors ; Biotechnology ; Blastocyst ; Cell Line ; Chickens ; Chimera ; Embryonic Germ Cells ; Embryonic Stem Cells ; Embryonic Structures ; Gene Transfer Techniques ; Germ Cells ; Gonads ; Mice ; Pluripotent Stem Cells ; Stem Cell Research* ; Stem Cells*

Early postnatal period is considered as the critical period for formation and maturation of the synapses. And cerebellum has the major role in the development of equilibrium and somatic motor function, especially in the early postnatal age. So, I performed this study to investigate the morphological changes of the synapses in the rat cerebellar cortex. Sprague-Dawley rats were used as experimental animals. The ultrastructure of Synapses was observed in six groups ; 3-day, 1-week, 2-week, 3-week, 4-week, 5-week. The results are as followes. 1. After birth, the synaptic density was increased gradually by the forth week. 2. The length of postsynaptic densities was increased significantly in the period between first and second week. 3. There was significant correlation between the length of postsynaptic densities and the area of synaptic vesicle clusters. 4. The frequency of asymmetric and/or frown synapses was increased dramatically with advancing ages. According to the above results, the synaptogenesis in the rat cerebellum is very active in their early postnatal periods. And asymmetric and/or active frown synapses were the major type of synapses with advancing ages.
Animals ; Cerebellar Cortex* ; Cerebellum ; Critical Period (Psychology) ; Parturition ; Post-Synaptic Density ; Rats* ; Rats, Sprague-Dawley ; Synapses* ; Synaptic Vesicles

BACKGROUND: It has been well known that cFos protein, one of the immediate-early gene proteins, was a cellular marker to characterize physiological or anatomical property of neural networks in mammalian brain. The purpose of this study was to evaluate quantitative change of cFos protein expression in rat brain nuclei concerned with regulation of blood pressure according to severity of hypotension and compare the spatial pattern of cFos between hemorrhagic hypotension and non-hemorrhagic hypotension elicited by vasodilatation. METHODS: The mean blood pressure (MBP) in the femoral artery was recorded by using pressure transducer and polygraph. Nitroprusside was injected into the femoral vein with constant flow rate by means of osmotic pump in which the dosage was 5microgram Per kg a minute. Immunohistochemical staining was Performed by using conventional ABC method to visualize cFos-like immunoreactive (cFLI) neurons in many brain nuclei and FLI cells were counted by image analyser. RESULTS: Mild hemorrhage group with MBP of 70-80 mmHg showed significant increase of cFLI expression in the paraventricular nuclei and supraoptic nuclei. In contrast, severe hemorrhage group with MBP of 50 mmHg increased significantly cFLI expression in the rostral ventrolateral medulla, periventricular thalamic nucleus, central gray matter, medial vestibular nuclei as well as the nuclei seen in mild hemorrhage group. Nitroprusside induced hypotension exhibited a similar spatial pattern of ctrl expression to severe hemorrhage group. CONCLUSION: These results suggest that severe reduction of blood pressure induces expression of cFLI neurons in the neural network systems that control vital organs.
Animals ; Blood Pressure ; Brain* ; Femoral Artery ; Femoral Vein ; Genes, Immediate-Early ; Hemorrhage ; Hypotension* ; Neurons ; Nitroprusside ; Rats* ; Transducers, Pressure ; Vasodilation ; Vestibular Nuclei

Purpose : As the recombinant human growth hormone has been widely available, a lots of parents having short statured children are interested in promoting growth of them whatever the etiologies of short stature they have. However, the growth hormone therapy for growth-promoting effect is only justified in well-established indications such as growth hormone deficiency, fumer syndrome, and chronic renal insufficiency. This study was undertaken to classify the children with chief complaint of short stature by its cause and giving the basic epidemiologic data for it so that the size of population in which growth hormone is indicated can be estimated. Methods : According to Ranke's etiologic classification, we categorized the 579 children who visited our pediatric endocrinology clinic with chief complaint of short stature during the period of March 1994 to August 1996. In this prospective study, history regarding growth was taken, physical examination and laboratory tests including bone age, thyroid function, blood chemistry were carried out. The auxological data were analyzed. Additional chromosomal study or growth hormone provocative tests were performed when needed. Results : Out of 579 patients, 360(62.2%) were classified as normal and 127(21.9%) were classified as normal variants which consist of familial [74(12.8%)], constitutional [48(8.5%)], and mixed familial & constitutional short stature[5(0.9%)]. Pathologic short stature was found in only 80(13.8%). Those are growth hormone deficiency(28), Tumer syndrome(16), intrauterine growth retardation(14) in order. Other etiologies list varieties of dysmorphism, skeletal dysplasia, chromosomal disorders. Conclusions : This results suggest the vast majority of children with chief complaint of short stature are normal or normal variants. Only 7.8% of children who visited our clinic were indicated for growth hormone therapy.
Chemistry ; Child* ; Chromosome Disorders ; Classification* ; Endocrinology ; Growth Hormone ; Human Growth Hormone ; Humans ; Parents ; Physical Examination ; Prospective Studies ; Renal Insufficiency, Chronic ; Thyroid Gland

To evaluate the correlation between the internal echo patterns and henodynamics in hepatic cavernous hemangioma, we compared the interanal echo pattern with the hemodynamic pattern examined by intravenous bolus CT(multi-phase incremental bolus dynamic CT) in 34 diagnosed hemangiomas (25 patients). We classified cavernous hemangiomas as two different hemodynamic patterns according to the findings of the early phase of intravenous bolus CT scans. Early enhancing type means that most portion of a mass is enhanced during the early hpase and late enhancing type means that only minimal peripheral portion of a mass is enhanced during the early phase. We classified ultrasonogrphic patterns as hypoechoic and hyperechoic according to main echogenicity of the mass. The late enhancing type tends toward the high echo type (20/21) and the early enhancing type tends to ward the low echo type (11/13) (p<0.01) Therefore, we believe that the early enhancing type which represents rapid contrast inflow toward mass, contains large portions of cavernous space and showes hypoechoic, but late enhancing type which represents late contrast inflow toward a mass, contains large portions of fibrous space and showes hyperechoic. In conclusion, there was significant correlation between internal hemodynamics and echo patterns in hepatic cavernous hemangioma.
Hemangioma ; Hemangioma, Cavernous* ; Hemodynamics* ; Tomography, X-Ray Computed

To evaluate the correlation between the internal echo patterns and henodynamics in hepatic cavernous hemangioma, we compared the interanal echo pattern with the hemodynamic pattern examined by intravenous bolus CT(multi-phase incremental bolus dynamic CT) in 34 diagnosed hemangiomas (25 patients). We classified cavernous hemangiomas as two different hemodynamic patterns according to the findings of the early phase of intravenous bolus CT scans. Early enhancing type means that most portion of a mass is enhanced during the early hpase and late enhancing type means that only minimal peripheral portion of a mass is enhanced during the early phase. We classified ultrasonogrphic patterns as hypoechoic and hyperechoic according to main echogenicity of the mass. The late enhancing type tends toward the high echo type (20/21) and the early enhancing type tends to ward the low echo type (11/13) (p<0.01) Therefore, we believe that the early enhancing type which represents rapid contrast inflow toward mass, contains large portions of cavernous space and showes hypoechoic, but late enhancing type which represents late contrast inflow toward a mass, contains large portions of fibrous space and showes hyperechoic. In conclusion, there was significant correlation between internal hemodynamics and echo patterns in hepatic cavernous hemangioma.
Hemangioma ; Hemangioma, Cavernous* ; Hemodynamics* ; Tomography, X-Ray Computed

No abstract available.
Thyroid Gland* ; Thyroid Nodule*

BACKGROUND: To collect the data related to the prevention of death in pediatric patients in the emergency center, the authors made a clinical analysis of pediatric death patients who visited the emergency center of Wonkwang University Hospital. METHODS: The authors performed a retrospective analysis of 49 pediatric deaths under the age of 16 years, observed in the Wonkwang University Hospital emergency center from January 1st, 1995 to December 31th, 1996. RESULTS: 1) Among a total of 49 pediatric patients who died (24 patients in 1995 and 25 patients in 1996), 19 patients were dead on arrival and 30 were died after arrival. 2) The cause of death of all the patients of 1 to 5 years old was the accident, and that of the majority patients of less than 1 year was disease. 3) We observed the diurnal variation in pediatric death and the rate was higher between 12:00 to 6:00. P.M. 4) Iksan city was the most common place of residency of the patients(71.4%) 5) 36 patients (73.5%) died from traffic accidents and 29 of them were victims of pedestrian traffic accidents. 6) The most common cause of death in accidents was head injury(54%). CONCLUSION: The majority of the pediatric death patients observed in our emergency center was involved in pedestrian traffic accident, head injury, so we conclude that team approach with pediatric trauma specialist could decreased unwanted pediatric deaths.
Accidents, Traffic ; Cause of Death ; Child, Preschool ; Craniocerebral Trauma ; Emergencies* ; Head ; Humans ; Internship and Residency ; Jeollabuk-do ; Retrospective Studies ; Specialization

BACKGROUND: To collect the data related to the clinical analysis of suicidal attempters who visited the emergency center of WonKwang University Hospital. METHODS: The authors performed a retrospective analysis of 306 suicide attempters, observed in the WonKwang University Hospital Emergency Center from January 1st, 1998 to December 31th, 1998. RESULTS: 1) Factors related to increased occurrence were male(1.1:1), age of 2nd, 3rd & above 6th decade. 2) Poisoning was the most common method of suicidal attempt(90.8%). 3) The average observation time was 18.76+/-23.3 hour and average staying time in admitted patients were 40.4+/-32.3 hour. 4) Mortality rate was in male 23.1%(37/160) and in female 10.0%(15/146). 5) Among the suicidal attempters who admitted, 56 patients were admission(11.8%). 6) Consultant of neuropsychiatric department was only 10.5%(18/172), and most common underlying psychiatric disorder was depression(10/18). CONCLUSION: 1) To develope observation room decrease staying time in suicidal attempters. 2) All suicidal attempters were necessarily neuropsychiatric consultant and continuously follow-up.
Consultants ; Emergencies* ; Female ; Follow-Up Studies ; Humans ; Male ; Mortality ; Poisoning ; Retrospective Studies ; Suicide

No abstract available.
Amino Acids* ; Animals ; gamma-Aminobutyric Acid* ; Horns* ; Neurons* ; Rats* ; Receptors, GABA*