The amino acid L-glutamate is a major excitatory neurotransmitter in the central nervous system of vertebrates(1). NMDA (N-methyl-d-aspartate) is one of the L-glutamate receptor subtypes(2). During a critical period of early postnatal development, the visual cortex is susceptible to experience-dependent modification of neuronal responses. Recently, the activation of NMDA receptors has been supposed as a prerequisite for the induction of such modification(3). We therefore investigated developmental changes of NMDA receptors in the rat visual cortex and questioned whether they could be related to the visual development. We assessed the density of [(3)H]-NMDA receptor in the visual cortex of normally reared rate (Group I) and visually deprived rats (Group II) using quantitative autoradiography(4). The density of [(3)H]-NMDA receptor was significantly lower in Group II than in group I during the early postnatal period, and increased rapidly by postnatal 1 week and, decreased after postnatal 5 weeks. These results suggested that NMDA receptors may play a role in neuronal development in the visual cortex during the early postnatal period.
Animals ; Autoradiography ; Dark Adaptation ; Eyelids/surgery ; Glutamates/metabolism ; Glutamic Acid ; Light ; Rats ; Receptors, N-Methyl-D-Aspartate/*metabolism ; Visual Cortex/growth & development/*metabolism

The amino acid L-glutamate is a major excitatory neurotransmitter in central nervous system of vertebrates. NMDA( n-methyl-d-aspartate) is one of the L-glutamate receptor subtypes. During a critical period of early postnatal development, the visual cortex is susceptible to experience-dependent modification of neuronal response. Recently, the activation of NMDA receptors has been supposed as an prerequisite for the induction of such modification We therefore investigated developmental changes of NMDA receptors in rat visual cortex and questioned whether they could be related to the visual development. We assessed the density of [3H] NMDA receptor in visual cortex of normally reared rats (Group I) and visually deprivated rats (Group II) using quantitative autoradiography. The density of [3H] NMDA receptor was increased rapidly by postnatal 1 week and decreased after postnatal 5 weeks, and was significantly lower in Group II than Group I during early postnatal period. These results suggest that NMDA receptors may have a role in neuronal development in visual cortex.
Animals ; Autoradiography ; Central Nervous System ; Critical Period (Psychology) ; Glutamic Acid ; N-Methylaspartate* ; Neurons ; Neurotransmitter Agents ; Rats* ; Receptors, N-Methyl-D-Aspartate* ; Vertebrates ; Visual Cortex*

A female newborn had the following characteristics; a congenital localized absence of skin over the lower extremities; blistering of the skin or mucous membrane, incited by trauma, which heals without scarring; and congenital absence or deformity of the nails. In respect to the characteristic manifestation, clinical course and electron microscopic features, our patient seems to fit well into Bart's syndrome. The inheritance pattern appears to be autosomal dominant but, as in this report, isolated cases have been recognized. As the review of the literatures, congenital localized absence of skin has been observed in various subsets of inherited E.B. But, we believe that the term Bart's syndrome should be used to identify patients with good prognosis as the Bart's initial description To the best of our knowedge, this is the first reported case of Bart's syndrome in the korean literature.
Blister ; Cicatrix ; Congenital Abnormalities ; Female ; Humans ; Infant, Newborn ; Inheritance Patterns ; Lower Extremity ; Mucous Membrane ; Prognosis ; Skin

No abstract available.
Cytokines* ; Mast Cells*

Thunderclap headache refers to a sudden and severe headache that comes unexpectedly, reminding one of a clap of thunder. The initial description of this type of headache was in association with an unruptured intracranial aneurysm. It is known to be a presenting feature of subarachnoid hemorrhage, unruptured intracranial aneurysm, cerebral venous thrombosis, cervical artery dissection, spontaneous intracranial hypotension, pituitary apoplexy, retroclival hematoma, and hypertensive reversible posterior leukoencephalopathy. A formula for diagnostic assessment of thunderclap headache, such as brain computed tomographic scan and spinal tap, should be established. We experienced a case of cerebral infarction presented with thunderclap headache, diagnosed using diffusion weighted magnetic resonance imaging. We suggest that, even when these patients have shown non-specific findings on neurological examination, brain computed tomography, and cerebrospinal fluid analysis, diffusion MRI should be considered for differential diagnosis of thunderclap headache in emergency medical services.
Arteries ; Brain ; Cerebral Infarction ; Diagnosis, Differential ; Diffusion ; Diffusion Magnetic Resonance Imaging ; Emergency Medical Services ; Headache ; Headache Disorders, Primary ; Hematoma ; Humans ; Infarction, Middle Cerebral Artery ; Intracranial Aneurysm ; Intracranial Hypotension ; Leukoencephalopathies ; Magnetic Resonance Imaging ; Neurologic Examination ; Pituitary Apoplexy ; Spinal Puncture ; Subarachnoid Hemorrhage ; Venous Thrombosis

No abstract available.
Acrosome* ; Fertilization* ; Humans* ; Male ; Spermatozoa*

Multiple primary cancer is relatively rare disease. But its study revealed a aspect of carcinogenesis and has changed our concept in second primary cancer. It is not a metastasis or recurrent cancer. Multiple primary cancer associated with gastric cancer is most common in Korea. Now we report two cases of multiple primary cancer in esophagus and stomach, successfully treated.
Carcinogenesis ; Esophagus* ; Korea ; Neoplasm Metastasis ; Neoplasms, Second Primary ; Rare Diseases ; Stomach Neoplasms ; Stomach*

PURPOSE: The purpose of this study was to examine the academic achievement of the first year medical students at Gachon University of Medicine and Science based on their characteristics (i.e. age, gender, and academic degree types (bachelors/masters), field of major (biology/ non-biology), and admission variables (i.e. MEET, GPA, attitude, interview, and English test). METHODS: The admission scores and demographic information were obtained from 39 students who had entered the university in 2005. T-test was used to examine the differences in academic achievement according to the students' characteristics. Correlations between admission variables and academic achievements were examined while multiple regression analysis was used to decipher the influence of students' characteristics and admission variables on the academic achievements. RESULTS: This study showed that the academic achievements differed significantly depending on degree level, age, and field of study, but not gender. It was also found that both the Nature Science Reasoning (NSR) of MEET subscale score and GPA score correlated significantly with academic achievement in the first year students. Attitude, interview, and English test scores did not correlate significantly. The result of the multiple regression analysis revealed that NSR 1 and 2, field of major, and age accounted for a substantial amount of the variance in academic achievement. CONCLUSION: Students with higher scores in NSR 1 and 2 who majored in biology-related fieldsand who are younger tend to do better academically in their first year of medical school. The results of this study may be helpful to graduate medical schools in designing effective admissions strategies for recruiting students, as well as, in planning the curriculum to improve the academic achievements of medical students.
Curriculum ; Humans ; Schools, Medical* ; Students, Medical

A 35-year-old woman suffered from elementary visual symptom that was confirmed as nonconvulsive simple partial status epilepticus arising from the right occipital lobe. 99mTc-ECD SPECT and 18F-FDG PET were done during the ictal and interictal phase, respectively, which were documented by EEG. Subtraction images of SPECT and PET were overlayed on the MRI by SISCOM to compare the area of metabolic change with that of perfusion change. There was no definite mismatch between the hypermetabolic area and the hyperperfusion area during nonconvulsive status epilepticus.
Adult ; Electroencephalography ; Female ; Fluorodeoxyglucose F18* ; Humans ; Magnetic Resonance Imaging ; Occipital Lobe* ; Perfusion ; Status Epilepticus* ; Tomography, Emission-Computed, Single-Photon*

OBJECTIVE: This study was to examine in vitro neural cell differentiation pattern of the genetically modified human embryonic stem cells expressing tyrosine hydroxylase (TH). MATERIALS AND METHODS: Human embryonic stem (hES, MB03) cell was transfected with cDNAs cording for TH. Successful transfection was confirmed by western immunoblotting. Newly transfected cell line (TH#2/MB03) was induced to differentiate by two neurogenic factors retinoic acid (RA) and b-FGF. Exp. I) Upon differentiation using RA, embryoid bodies (EB, for 4 days) derived from TH#2/MB03 cells were exposed to RA (10-6 M)/AA (5x10-2 mM) for 4 days, and were allowed to differentiate in N2 medium for 7, 14 or 21 days. Exp. II) When b-FGF was used, neuronal precursor cells were expanded at the presence of b-FGF (10 ng/ml) for 6 days followed by a final differentiation in N2 medium for 7, 14 or 21 days. Neuron differentiation was examined by indirect immunocytochemistry using neuron markers (NF160 & NF200). RESULTS: After 7 days in N2 medium, approximately 80% and 20% of the RA or b-FGF induced Th#2/MB03 cells were immunoreactive to anti-NF160 and anti-NF200 antibodies, respectively. As differentiation continued, NF200 in RA treated cells significantly increased to 73.0% on 14 days compared to that in b-FGF treated cells (53.0%, p<0.05), while the proportion of cells expressing NF160 was similarly decreased between two groups. However, throughout the differentiation, expression of TH was maintained (~90%). HPLC analyses indicated the increased levels of L-DOPA in RA treated genetically modified hES cells with longer differentiation time. CONCLUSION: These results suggested that a genetically modified hES cells (TH#2/MB03) could be efficiently differentiated in vitro into mature neurons by RA induction method.
Antibodies ; Blotting, Western ; Cell Differentiation* ; Cell Line ; Chromatography, High Pressure Liquid ; DNA, Complementary ; Embryoid Bodies ; Embryonic Stem Cells* ; Humans* ; Immunohistochemistry ; Levodopa ; Neurons ; Transfection ; Tretinoin ; Tyrosine 3-Monooxygenase* ; Tyrosine*