PURPOSE: Numerous studies have been performed about the various safety consideration of magnetic resonance(MR). Multiple investigators have failed to reveal any deleterious defects of MR. On the other hand, several studies have demonstrated detectable biologic effects of high-field MR produces any morphologic changes on the cell membrane and intracellular ultrastructures in human peripheral blood lymphocytes in vitro. MATERIALS AND METHODS: Lymphocytes were isolated from peripheral blood of normal human adults by Ficoll-Hypaque density centrifugation. Exposure to MR was performed with 4.69T and 11.74T MR spectrometer with a radio frequency(RF) pulse of 200MHz and 500MHz. Exposure times varyed from 30 minutes to 3 hours. The cells were fixed immediately, 1, 3, 7 days after MR exposure. Morphologic evaluation was examined by transmission electron microscopy(TEM). RESULTS: Under TEM there was cell transformation including cellular membrane, nucleus and intracellular microorganelles on lymphocytes exposed to MR. The percentage of transformed lymphocytes was not significantly increased after 4.69T MR exposure, whereas the percentage of transformed lymphocytes was significant increased after 11.74T MR exposure(P<0.05) compared with that of control. The percentage of transformed lymphocytes was significantly increased at the long incubation period in control and MR exposure group(P<0.05). No change according to MR exposure time and RF pulse sequence was noted. CONCLUSION: Exposure to high-field MR induces morphologic transformations of lymphocytes in vitro. Additional studies have to be performed before definitive conclusion can be reached about the safety of high-field MR.
Adult ; Cell Membrane ; Centrifugation ; Hand ; Humans* ; Lymphocytes* ; Membranes ; Research Personnel

OBJECTIVE: In the previous study, we compiled the differentially expressed genes during early folliculogenesis.1 Objective of the present study was to identify downstream target genes of transcription factors (TFs) using bioinformatics for selecting the target TFs among the gene lists for further functional analysis. MATERIALS AND METHODS: By using bioinformatics tools, constituent domains were identified from database searches using Gene Ontology, MGI, and Entrez Gene. Downstream target proteins/genes of each TF were identified from database searches using TF database (TRANSFAC(R) 6.0) and eukaryotic promoter database (EPD). RESULTS: DNA binding and trans-activation domains of all TFs listed previously were identified, and the list of downstream target proteins/genes was obtained from searche of TF database and promoter database. Based on the known function of identified downstream genes and the domains, 3 (HNF4, PPARg, and TBX2) out of 26 TFs were selected for further functional analysis. The genes of wee1-like protein kinase and p21WAF1 (cdk inhibitor) were identified as potential downstream target genes of HNF4 and TBX2, respectively. PPARg, through protein-protein interaction with other protein partners, acts as a transcription regulator of genes of EGFR, p21WAF1, cycD1, p53, and VEGF. Among the selected 3 TFs, further study is in progress for HNF4 and TBX2, since wee1-like protein kinase and cdk inhibitor may involved in regulating maturation promoting factor (MPF) activity during early folliculogenesis. CONCLUSIONS: Approach used in the present study, in silico analysis of downstream target genes, was useful for analyzing list of TFs obtained from high-throughput cDNA microarray study. To verify its binding and functions of the selected TFs in early folliculogenesis, EMSA and further relevant characterizations are under investigation.
Computational Biology ; Computer Simulation* ; DNA ; Gene Ontology ; Maturation-Promoting Factor ; Oligonucleotide Array Sequence Analysis ; Protein Kinases ; Transcription Factors* ; Vascular Endothelial Growth Factor A

PURPOSE: The occurrence of traumatic aneurysm is rare in head injury, but this complication is important as it is a potentially treatable cause delayed onset of intracranial hemorrhage. Authors report one case of traumatic aneurysm involving A1 and A2 junction of anterior cerebral artery. MATERIALS AND METHODS: A-28-year-old man with traffic accident was examined with brain CT & cerebral angiography. RESULTS: l) Brain CT:lnitial scan shows multiple skull fractures involving right frontal bones with subarachnoid hemorrhage and pneumocephalus. Follow-up scan shows intracerebral hemorrhage at bilateral frontal lobes. 2) Cerebral angiography:A traumatic aneurysm which is slowly filling and delayed emptying is noted at the junctional portion of A1 and A2 segment of the anterior cerebral artery. CONCLUSION: This report demonstrates radiologic findings of traumatic aneurysm at anterior cerebral artery with the brief review of the literatures.
Accidents, Traffic ; Aneurysm ; Anterior Cerebral Artery ; Brain ; Cerebral Angiography ; Cerebral Hemorrhage ; Craniocerebral Trauma ; Follow-Up Studies ; Frontal Bone ; Frontal Lobe ; Intracranial Aneurysm* ; Intracranial Hemorrhages ; Pneumocephalus ; Skull Fractures ; Subarachnoid Hemorrhage

From March 1987 to July 1989, six patients (five dadults and one child) with lung abscess (size, 5-13cm in diameter) were treated with percutaneous aspiration and drainage. In each case, the puncture was made where the wall of the abscess was in contact with the pleural surface. An 8 to 10 Fr catheter was inserted for drainage. Five of 6 had a dramatic clinical response within 24 hours of the drainage. Percutaneous drainage was successful with complete abscess resolution in four and partial resolution in one patient. No response was seen in the rest one. The duration of drainage ranged from 7 to 18 days (average, 15.5days) in successful cases. One case of the failure in drainage was due to persistent aspiration of the neurologically impaired patient. In one patient, the abscess resolved after drainage but recurred after inadvertent removal of the catheter 7 days after insertion. In two patients, concurrent pleural empyema was resolved completely by the drainage. Computed tomography provided anatomic details necessary for choosing the puncture site and avoiding a puncture of the lung parenchyma. Percutaneous catheter drainage is a safe and effective method for treating patients with lung abscess.
Abscess ; Catheters* ; Drainage* ; Empyema, Pleural ; Humans ; Lung Abscess* ; Lung* ; Methods ; Punctures

PURPOSE: To assess the value of MR imaging compared to CT for the staging of gastric carcinoma when body-wrap-around surface coil, intravenous glucagon, motion suppression technique and effervescent granules are used. MATERIAL AND METHOD: CT and MRI were performed for thirty-five patients with gastric carcinoma. Postcontrast CT scan was performed immediately after oral effervescent granules and Buscopan were given. Before MR imaging, BWA surface coil was wrapped around the upper abdomen. T1 coronal, sagittal and axial SE images (TRITE=400/15 msec) were obtained immediately after oral effervescent granules and glucagon were given. Respiratory compensation and presaturation techniques were used for each imaging. Three radiologists evaluated independently for randomly mixed 70 sets of CT and MR images. The signal intensity of gastric mass and enlarged lymph nodes were compared to the signal intensity of the adjacent pancreas, liver and spleen to evaluate any discriminating features between them. RESULTS: The accuracy in the diagnosis of pancreatic invasion was 83.8% on MRI and 74.3% on CT (p < 0.05). The accuracy of MRI and CT was 77.1% and 72.4% in detecting of gastric tumor respectively (p > 0.05), 73.3% and 68.6% in gastric serosal invasion (p> 0.05), 50.5% and 42.9% in lymph node metastasis (p > 0.05). The gastric mass and enlarged lymph nodes were hypointense to the intensity of pancreas and liver in more than 78% of cases. CONCLUSION: MRI was comparable to CT scan for the staging of gastric carcinoma. Therefore, MRI could be used as an alternative or adjunctive diagnostic modality in the staging of gastric carcinoma.
Abdomen ; Butylscopolammonium Bromide ; Compensation and Redress ; Diagnosis ; Glucagon ; Humans ; Liver ; Lymph Nodes ; Magnetic Resonance Imaging* ; Neoplasm Metastasis ; Pancreas ; Spleen ; Tomography, X-Ray Computed

No abstract available.
Animals ; Brain Stem* ; Brain* ; Electroshock* ; Hypothalamus* ; Mice*

We present a case in which a patient with acute hemorrhagic gastritis demonstrated abnormal gastrointestinal accumulation of radiotracer during Tc-99m-methylene diphosphonate (MDP) skeletal scintigraphy. A hemorrhage gastritis was subsequsently demonstrated by endoscopy. The menchanism for the intestinal localization of Tc-99m-MDP in this patient is not clear, but we guess that the extravasated blood containing the radiopharmaceutical cannot recirculate and stays at the bleedings site, so we can see the intestinal activity.
Endoscopy ; Gastritis ; Hemorrhage* ; Humans ; Radionuclide Imaging* ; Technetium Tc 99m Medronate*

Correct localization of epileptogenic zone is important for the successful epilepsy surgery. Both ictal perfusion single photon emission computed tomography (SPECT) and interictal F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) can provide useful information in the presurgical localization of intractable partial epilepsy. These imaging modalities have excellent diagnostic sensitivity in medial temporal lobe epilepsy and provide good presurgical information in neocortical epilepsy. Also provide functional information about cellular functions to better understand the neurobiology of epilepsy and to better define the ictal onset zone, symptomatogenic zone, propagation pathways, functional deficit zone and surround inhibition zones. Multimodality imaging and developments in analysis methods of ictal perfusion SPECT and new PET ligand other than FDG help to better define the localization.
Epilepsies, Partial ; Epilepsy* ; Epilepsy, Temporal Lobe ; Neurobiology ; Perfusion ; Positron-Emission Tomography ; Tomography, Emission-Computed, Single-Photon

Alzheimer's disease (AD) is a neurodegenerative disorder associated with extracellular plaques, composed of amyloid-beta (Aβ), in the brain. Although the precise mechanism underlying the neurotoxicity of Aβ has not been established, Aβ accumulation is the primary event in a cascade of events that lead to neurofibrillary degeneration and dementia. In particular, the Aβ burden, as assessed by neuroimaging, has proved to be an excellent predictive biomarker. Positron emission tomography, using ligands such as ¹¹C-labeled Pittsburgh Compound B or ¹⁸F-labeled tracers, such as ¹⁸F-florbetaben, ¹⁸F-florbetapir, and ¹⁸F-flutemetamol, which bind to Aβ deposits in the brain, has been a valuable technique for visualizing and quantifying the deposition of Aβ throughout the brain in living subjects. Aβ imaging has very high sensitivity for detecting AD pathology. In addition, it can predict the progression from mild cognitive impairment to AD, and contribute to the development of disease-specific therapies.
Alzheimer Disease ; Brain ; Dementia ; Ligands ; Mild Cognitive Impairment ; Neurodegenerative Diseases ; Neuroimaging ; Pathology ; Positron-Emission Tomography

Alzheimer's disease (AD) is a neurodegenerative disorder associated with extracellular plaques, composed of amyloid-beta (Aβ), in the brain. Although the precise mechanism underlying the neurotoxicity of Aβ has not been established, Aβ accumulation is the primary event in a cascade of events that lead to neurofibrillary degeneration and dementia. In particular, the Aβ burden, as assessed by neuroimaging, has proved to be an excellent predictive biomarker. Positron emission tomography, using ligands such as ¹¹C-labeled Pittsburgh Compound B or ¹⁸F-labeled tracers, such as ¹⁸F-florbetaben, ¹⁸F-florbetapir, and ¹⁸F-flutemetamol, which bind to Aβ deposits in the brain, has been a valuable technique for visualizing and quantifying the deposition of Aβ throughout the brain in living subjects. Aβ imaging has very high sensitivity for detecting AD pathology. In addition, it can predict the progression from mild cognitive impairment to AD, and contribute to the development of disease-specific therapies.