In order to evaluate the ability of spin-echo MR imaging to differentiate slow flow from mural thrombus in aortic diseases, we reviewed the spin-echo MR images of 13 patients with intraaortic thrombus documented by CT (N=11) or aortography (N=2). Six patients had aortic aneurysms and seven had aortic dissection. Intraaortic mural thrombi were accompanied by flow-related intraluminal signal of various patterns and extents in all 13 patients. On 10 gated MR studies, slow flow regions showed even-echo rephasing phenomenon (N=8), interslice variation of signal intensities of the intraluminal signal (N=7) and flow-related ghost artifact (N=2). However, these MR flow phenomena were obscured on two of three non-gated studies. Seven of 13 intraaortic thrombi remained hyperintense on T2-weighted second-echo images. In these circumstances, a hypointense boundary layer between slow flow and mural thrombus, which was caused by either 'boundary layer dephasing phenomenon' of slow flow or 'paramagnetic T2 shortening' of fresh clot at the edge of mural thrombus, was useful in discriminating the area of slow flow from that of mural thrombus. Proper interpretation of spin-echo MR images may obviate the need for phase display imaging or gradientecho imaging in differentiating slow flow and mural thrombus.
Aortic Aneurysm ; Aortic Diseases* ; Aortography ; Artifacts ; Humans ; Magnetic Resonance Imaging ; Thrombosis*

In order to evaluate the ability of spin-echo MR imaging to differentiate slow flow from mural thrombus in aortic diseases, we reviewed the spin-echo MR images of 13 patients with intraaortic thrombus documented by CT (N=11) or aortography (N=2). Six patients had aortic aneurysms and seven had aortic dissection. Intraaortic mural thrombi were accompanied by flow-related intraluminal signal of various patterns and extents in all 13 patients. On 10 gated MR studies, slow flow regions showed even-echo rephasing phenomenon (N=8), interslice variation of signal intensities of the intraluminal signal (N=7) and flow-related ghost artifact (N=2). However, these MR flow phenomena were obscured on two of three non-gated studies. Seven of 13 intraaortic thrombi remained hyperintense on T2-weighted second-echo images. In these circumstances, a hypointense boundary layer between slow flow and mural thrombus, which was caused by either 'boundary layer dephasing phenomenon' of slow flow or 'paramagnetic T2 shortening' of fresh clot at the edge of mural thrombus, was useful in discriminating the area of slow flow from that of mural thrombus. Proper interpretation of spin-echo MR images may obviate the need for phase display imaging or gradientecho imaging in differentiating slow flow and mural thrombus.
Aortic Aneurysm ; Aortic Diseases* ; Aortography ; Artifacts ; Humans ; Magnetic Resonance Imaging ; Thrombosis*

To evaluate the radioprotective effects of 5-thio-D-glucose(5-TDG) on normal skin, an experimental study was carried out with total 140 mice, of which 30 mice were given 5-TDG followed by irradiation and 60 mice were given intraperitoneally (IP) two hours before irradiation, and the radiation doses were singly 2500, 3500 or 4500 radsrespectively. The skin changes of the irradiated right hind limb were inspected for 31 days and the skin scores were analized. The results are as follow; 1. Marked radioprotective effect was presented in the group of 5-TDG,1.5g/kg body weight, with 2500 rads irradiation. 2. Definite radioprotective effect was also revealed in the groupof 5-TDG, 1.5kg/ body weight, with 3500 rads irradiation, In the group of double dose 5-TDG, 3.0g/kg body weight, the radioprotective effect appeared to be enhanced. 3. In the group of 4500 rads irradiation with 5-TDG, 1.5g/kgbody weight, no radioprotective effect was noticed. 4. In addition to the radiosensitization effect on the hypoxiccells, the radioprotective effect of 5-TDG on the normal animal tissue suggests increased possiblility of itsclinical application.
Animals ; Body Weight ; Extremities ; Mice ; Skin

Computerized Tomography can make accurate diagnosis in most of the mediastinal tumors and cysts by assessingtheir location, shape and internal architecture. Authors analysed and present CT findings of 89 surgically provenmediastinal tumpors and cysts that were studied and treated in Seoul National University Hospital during recent 5years. The results are as follows; 1. The most common tumor was teratoma(25 cases). Neurogenic tumor (20 cases),thymic tumor or cyst (16 cases), lymphoma(7 cases), bronchogenic cyst (6 cases), intrathoracic goiter (6 cases),pericardial cyst(3 cases) and cystic hygroma(2 cases) were next in order of frequency. 2. The most constant findings of teratoma was thick walled cystic area(100%), while pathognomonic fat and calcified density were seenonly in 52% and 48% of cases, respectively. 22 cases were located in anterior mediastinum, 2 cases were inposterior mediastinum and a case is in middle mediastinum. 3. There were 20 cases of neurogenic tumor consiting of6 neurilemmomas, 7 ganglioneuromas, 4 neurofibromas, 1 ganglioneuroblastoma, 1 neuroblastoma and 1 malignantschwannoma. Most of them were located in posterior mediastinum with exception of 2 neurilemmomas arising from leftvagus nerve and left recurrent laryngeal nerve in middle mediastinum. Cystic change was seen in 2 cases ofneurilemmoma and in a case of ganglioneuroma. Calcification was seen in 3 cases, of neuroblastoma, aneurilemmoma,and a ganglioneuroma. 4. There were 11 cases of thymoma showing homogeneous solid mass with speckeldcalcification in 4 cases and irregular cystic change in 3 cases. 2 cases were invasive thymoma and myastheniagravis was present in 4 cases. A case of thymolipoma and a case of thymic cyst were included. 5. Lymphoma(2Hodgkin's and 4 non-Hodgkin's) appeared as lobulated, matted mass in anterior mediastinum especially inprevascular area expnading bilaterally. 6. Intrathoracic goiter appeared as slingtly high density mass within termingled calcification and cystic area in 5 cases of secondary goiter and homogeneous high densitymass(100-110 H.U. in precontrast scan) in a case of primary goiter. 7. Among the 6 bronchogenic cysts, 3 werelocated in subcarinal area, 2 were above carina and one was in left hilar area. 3 cases showed high CT number morethan 70 H.U. and others showed water density. 8. 3 cases of pericardial cyst were located in right cardiophrenicangle and all of them showed water density. 9. 2 cases of cystic hygroma were located in superior mediastinum,with extension to lower neck and all of them showed water density.
Bronchogenic Cyst ; Diagnosis ; Ganglioneuroblastoma ; Ganglioneuroma ; Goiter ; Goiter, Substernal ; Granuloma ; Lymphangioma, Cystic ; Mediastinal Cyst ; Mediastinum ; Neck ; Neurilemmoma ; Neuroblastoma ; Neurofibroma ; Recurrent Laryngeal Nerve ; Seoul ; Teratoma ; Thymoma ; Water

Open brochus with diffuse narrowing, stretching, and leafless tree appearance of the bronchi is the well know bronchographic criterior of bronchiloalveolar carcinoma. Though similar findings are expected in CT, authors couldfind no report concerninng the open bronchus sign of bronchioloalveolar carcinoma demonstrated by CT., Authorspresents CT of bronchioloalveolar carcinoma showing lobar or segmental distribution and patent bronchus within thetumor mass.
Adenocarcinoma, Bronchiolo-Alveolar ; Bronchi ; Trees

No abstract available.
Adhesives* ; Intestinal Obstruction*

In spite of the extensive use of antibiotics over several decades, Streptococcus pneumoniae still remains as one of the most serious human bacterial pathogens. In order to clone the pneumococcal genes whose expression is induced when pneumococcus causes infection in mice, S. pneumoniae strain ATCC 6303 was subcultured on blood agar plates (BAP) ten times to reduce the virulence first, and then passaged through BALB/c mice three times to restore the virulence. Subtractive hybridization was performed using the total RNA preparations isolated from BAP-cultured and mouse-passaged strains. Complementary DNAs corresponding to any mRNA species that were differentially expressed in the mouse- passaged strain were used as the probes to screen the genomic library of pneumococcus. Positive recombinants were selected and sequenced partially to identify the genes located within the cloned DNA. GenBank search of the sequence data has identified several genes including two heat shock genes (dnaK and dnap, a transposase-encoding gene, and a sequence which is very homologous to that of the ftsH gene.
Agar ; Animals ; Anti-Bacterial Agents ; Clone Cells* ; Cloning, Organism* ; Databases, Nucleic Acid ; DNA ; DNA, Complementary ; Genomic Library ; Hot Temperature ; Humans ; Mice ; Pneumonia ; RNA ; RNA, Messenger ; Shock ; Streptococcus pneumoniae* ; Streptococcus* ; Virulence

No abstract available.
Animals ; Ascitic Fluid* ; Intestinal Obstruction* ; Lactic Acid* ; Rats*

The leprous involvement of the ankle joint and the upper surface of the talus is said to be a rare entity and this is in sharp contract to the Charcot joint of other causes in which the ankle involvement is relatively common. This can partly be explained by the concept that the articular branch of tibial nerve to the ankle joint is usually spare din leprosy, although the fibular nerve is affected around the knee level. During the survey of nearly 3000 leprous patients in the National Leprosy Center we selected 26 cases with obvious bone change of the ankle joint and the clinical study on these 26 cases was made with the following results. 1. The 26 cases consisted of 15 males and 11 females 2. Average age of the patients was 56 years and those over 50 years numbered 20(77%)and undre 39 years of age there was only one involvement. 3. Ankle destruction can be classified according to the causative factors attributable to its occurrence as follows: destruction of ankle joint following fracture of which four were Potts type and eight hyperdorsif-lexion injury: those following idiopathic arthritis in four, and those following subtalar incongruity due to calcaneal flattening in ten. 4. The results of this study which clarify the pathogenesis of ankle involvement in leprous patients may offer reliable preventive measures for each case of ankle destruction.
Ankle Joint ; Ankle ; Arthritis ; Arthropathy, Neurogenic ; Clinical Study ; Female ; Humans ; Knee ; Leprosy ; Male ; Peroneal Nerve ; Talus ; Tibial Nerve

The study was undertaken to detemine the effect of fractionated high-dose total lymphoid irradiation (TLI) onthe servival of skin allograft despite major histocompatibility difference. Total lymphoid irraditation is arelatively safe form of radiotherapy, has been used extensively to treat lymphoid malignancies in humans with fewside effects. A total of 90 rats, Sprague-Dawley rat as recipient and Wistar rat as donor, were used for theexperiment, of which 10 rats were used to determine mixed lymphocyte response (MLR) for antigenic difference andskin allografts was performed in 30 rats given total lymphoid irradiation to assess the immunosuppressive effectof total lymphoid irradiation despite major histocompatibility difference. In addition, the peripheral white bloodcell counts and the proportion of lymphocytes was studied in 10 rats given total lymphoid irradiation but no skingraft to determine the effects of bone marrow suppression. The results obtained are summerized as follows. 1. Theoptimum dose of total lymphoid irradiation was between 1800 rads to 2400 rads. 2. The survival of skin graft onrats given total lymphoid irradiation (23.2±6.0days) was prolonged about three folds as compared to unirradiated-control (8.7±1.3 days). 3. Total lymphoid irradiation resulted in a severe leukopneia with marked lymphopenia,but the count was normal by the end of 3rd week. 4. The study suggests that total lymphoid irradiation is anonlethal procedure that could be used successfully in animals to transplant allograft across major-histocompatibility barriers.
Allografts ; Animals ; Bone Marrow ; Histocompatibility ; Humans ; Lymphatic Irradiation ; Lymphocytes ; Radiotherapy ; Rats ; Rats, Sprague-Dawley ; Skin ; Tissue Donors ; Transplants