Biomedical subjects
Publications and source records attributed to H D Kim.
Based on the fact that the ring expanded 3'-C-hydroxymethyl analogue of oxetanocin A exhibited potent antiviral activity, two types of conformationally rigid 3'-C-hydroxymethyl derivatives in which 2'-hydroxyl group is linked to the 4'-position or to the 6'-position were synthesized starting from 1,2;5,6-di-O-isopropylidene-D-glucose, respectively.
D- and L-3'-Deoxy-3'-C-hydroxymethyl thymidine substituted with exocyclic methylene at 2'-position were synthesized, starting from D- and L-xylose as potential ribonucleotide reductase inhibitor, respectively, but they were found to be inactive against several tumor cell lines.
OBJECTIVE: The aim of this study was to compare CT and MRI at 0.5 T in the preoperative staging of uterine cervical cancer in a large series of patients. MATERIALS AND METHODS: Ninety-nine patients with uterine cervical carcinoma underwent CT, MRI, and surgical exploration. RESULTS: Both CT and MR findings were compared using surgical-pathologic findings as gold standards. Magnetic resonance imaging was superior to CT in tumor detection (sensitivity 75 vs. 51%, p < 0.005), in parametrial evaluation (accuracy 87 vs. 80%, p < 0.005), in overall tumor staging (accuracy 77 vs. 69%, p < 0.025), and in pelvic lymph node evaluation (accuracy 88 vs. 83%, p < 0.01). Magnetic resonance imaging had an accuracy of 76% in assessment of the thickness of cervical stromal invasion. CONCLUSION: Magnetic resonance imaging was superior to CT in preoperative staging of uterine cervical carcinoma and MRI should be used instead of CT for preoperative staging of this disease.
OBJECTIVE: The aim of this study was to compare the accuracy of transvaginal US (TVUS), CT, and MRI in detecting deep myometrial invasion in endometrial carcinoma. MATERIALS AND METHODS: Twenty-six patients with endometrial carcinoma were evaluated with TVUS, CT, and MRI. The depth of myometrial invasion was estimated in each examination. The invasion depth was categorized into no/superficial and deep and was compared to surgical and pathologic findings. RESULTS: At pathologic examination, the depth of myometrial invasion was no/superficial in 16 patients and deep in 10. The accuracy/sensitivity/specificity of TVUS, CT, and MRI in detecting deep myometrial invasion were 69/50/81, 61/40/75, and 89%/90%/88%, respectively. The sensitivity and accuracy of MRI in detecting deep myometrial invasion were significantly higher than those of TVUS and CT (p = 0.049 for both sensitivity and accuracy). CONCLUSION: We recommend MRI instead of CT or TVUS for the evaluation of the depth of myometrial invasion in endometrial carcinoma.
OBJECTIVE: The purpose of our study was to determine the ability of H-1 MR spectroscopy (MRS) to lateralize the lesion in patients with hippocampal sclerosis. MATERIALS AND METHODS: Twenty healthy volunteers and 25 patients with intractable temporal lobe epilepsy whose MR imaging diagnosis was unilateral hippocampal sclerosis were included. This diagnosis was based on the presence of unilateral atrophy and/or high T2 signal intensity of the hippocampus. Singlevoxel H-1 MRS was carried out on a 1.5-T unit using PRESS sequence (TE, 136 msec). Spectra were obtained from hippocampal areas bilaterally with volumes of interest (VOIs) of 6.0 cm(3) and 2.25 cm(3) in healthy volunteers, and of either 6.0 cm(3) (n = 14) or 2.25 cm(3) (n = 11) in patients. Metabolite ratios of NAA/Cho and NAA/Cr were calculated from relative peak height measurements. The capability of MRS to lateralize the lesion and to detect bilateral abnormalities was compared with MR imaging diagnosis as a standard of reference. RESULTS: In healthy volunteers, NAA/Cho and NAA/Cr ratios were greater than 0.8 and 1.0, respectively. In patients, the mean values of these ratios were significantly lower on the lesion side than on the contralateral side, and lower than those of healthy volunteers (p <.05). The overall correct lateralization rate of MRS was 72% (18/25); this rate was lower with a VOI of 6.0 cm(3) than of 2.25 cm(3) (64% versus 82%, p <.05). Bilateral abnormalities on MRS were found in 24% (6/25) of cases. CONCLUSION: Although its rate of correct lateralization is low, single-voxel H-1 MRS is a useful and promising diagnostic tool in the evaluation of hippocampal sclerosis, particularly for the detection of bilateral abnormalities. To improve the diagnostic accuracy of H-1 MRS, further investigation, including the use of a smaller VOI and measurement of the absolute amount of metabolites, are needed.
OBJECTIVE: To determine the extent to which thin-section and volumetric threedimensional CT can depict airway reactivity to bronchostimulator, and to assess the effect of different airway sizes on the degree of reactivity. MATERIALS AND METHODS: In eight dogs, thin-section CT scans were obtained before and after the administration of methacholine and ventolin. Cross-sectional areas of bronchi at multiple levels, as shown by axial CT, proximal airway volume as revealed by three-dimensional imaging, and peak airway pressure were measured. The significance of airway change induced by methacholine and ventolin, expressed by percentage changes in cross-sectional area, proximal airway volume, and peak airway pressure was statistically evaluated, as was correlation between the degree of airway reactivity and the area of airways. RESULTS: Cross-sectional areas of the bronchi decreased significantly after the administration of methacholine, and scans obtained after a delay of 5 minutes showed that normalization was insufficient. Ventolin induced a significant increase in cross-sectional areas and an increase in proximal airway volume, while the effect of methacholine on the latter was the opposite. Peak airway pressure increased after the administration of methacholine, and after a 5-minute delay its level was near that of the control state. Ventolin, however, induced no significant decrease. The degree of airway reactivity did not correlate with airway size. CONCLUSION: Thin-section and volumetric spiral CT with three-dimensional reconstruction can demonstrate airway reactivity to bronchostimulator. The degree of reactivity did not correlate with airway size.