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Biomedical subjects

Y T Ko

Publications and source records attributed to Y T Ko.

44 records · Page 3Linked to original sources

Microbial production of lysine and threonine from whey permeate.

Extracellular accumulation of lysine and threonine was investigated in modified whey permeate by using Brevibacterium lactofermentum ATCC 21086 and Escherichia coli ATCC 21151. Whey permeate was prepared from whey by membrane ultrafiltration, and lactose was hydrolyzed by treating permeate with HCl or beta-galactosidase. The highest amount of lysine (3.3 g/liter) was produced from a mixture of acid-hydrolyzed whey permeate and yeast extract (0.2%). The highest amount of threonine (3.6 g/liter) was produced from a mixture of whey permeate, (NH(4))(2)SO(4) (1.4%), yeast extract (0.1%), and Na(2)CO(3) (0.3%).

Journal Article↗

Growth and liver lipids of casein-fed rats incubated in the presence of glucose and lipid.

The effect of casein that has reacted with glucose and/or lipid on the growth and hepatic lipids of rats was studied. A mixture of casein-ethyl linoleate-glucose was kept at 50 degrees C and RH 80.4% for 14 days and defatted with ethyl ether and acetone. When the casein that had reacted with glucose and lipid was fed at at 10% dietary level for 14 days, the growth of rats was markedly depressed. Not only levels of hepatic lipids but also of plasma lipids were specifically modified. The accumulation of hepatic lipids was primarily due to the increase in triglyceride. When casein was reacted with glucose alone, similar but considerably lesser changes in the growth and liver lipid components were observed. These data indicate that casein characteristically deteriorates with glucose and/or lipid, but the effect of oxidation of the latter is very remarkable.

Animals↗

Transabdominal US staging of gastric cancer.

Penetration of gastric cancer through the wall is important because the treatment modality and prognosis are accordingly different. A prospective study was performed to assess the value of transabdominal ultrasonography in the differentiation of early gastric cancer limited within the mucosa and submucosa from advanced cancer extending into the muscle layer. Fifteen patients with early gastric cancer and 29 patients with advanced gastric cancer were evaluated preoperatively and compared with histological findings. Patients were referred after endoscopy and sonologists were informed of the site of the gastric lesions. Patients ingested 600-800 ml of boiled water and transabdominal ultrasonography of the gastric lesion was accomplished using a commercially available ultrasound equipment with 5.0 and 3.5 MHz transducers. Using the intact middle hyperechoic layer on sonogram as the criterion for early cancer, 10 of 15 patients with early gastric cancer and 27 of 29 patients with advanced gastric cancer were correctly diagnosed (84%). Fourteen of 15 cases with early gastric cancer showed a thickness of the lesion below 1.0 cm, while seven of 29 cases with advanced cancer showed a thickness 1.0 cm or less. We believe that transabdominal sonography may be a valuable method in the differentiation between early and advanced gastric cancer.

Adult↗

Advanced gastric carcinoma: the role of three-dimensional and axial imaging by spiral CT.

BACKGROUND: The purpose of this study was to assess the role of three-dimensional (3D) and axial imaging by spiral computed tomography (CT) in the evaluation of advanced gastric carcinoma (AGC). METHODS: Sixty patients with AGC underwent 3D and axial imaging by spiral CT. Among them, 40 cases were confirmed by surgery. The remaining 20 cases showed typical findings of AGC with upper gastrointestinal series and gastroscopy that were proved by endoscopic biopsy. Spiral CT was performed with 3-mm collimation, 4. 5-mm/s table feed, and 1.5-mm reconstruction interval in the supine position after ingestion of gas. Three-dimensional images using the shaded surface display (SSD) technique were analyzed and graded (excellent, good, or poor). A second dual-phase spiral CT scan was performed with 5-mm collimation, 7-mm/s table feed, and 5-mm reconstruction interval in the prone position after ingestion of water. RESULTS: Among 60 cases of AGC, there were two cases (3.4%) of Borrmann type 1, 12 cases (20.0%) of Borrmann type 2, 32 cases (53.3%) of Borrmann type 3, 11 cases (18.3%) of Borrmann type 4, and three cases (5.0%) of Borrmann type 5. Of the 60 cases of AGC, excellent 3D images were obtained in nine patients (15.0%), good 3D images in 39 (65.0%), and poor 3D images in 12 (20.0%). Among the 12 patients with poor images, cancers were located at the pyloric antrum in eight cases (66.7%), were AGC Borrmann type 4 in three cases (25.0%), and early gastric carcinoma (EGC)-mimicking lesion (AGC Borrmann type 5) in one case (8.3%). Cancers involving the antrum tended to show poor images (p < 0.05). Using axial images, Borrmann's classification based on tumor morphology was accurately identified in 41 cases (68.3%); however, using 3D imaging, 52 cases (86.7%) were accurately classified (p < 0.05). In 40 cases receiving surgery, good correlation between axial CT image and pathology occurred in 70.0% of T class and 72.5% of N class. CONCLUSIONS: Three-dimensional images of AGC by spiral CT data were good or excellent in 80%, and combining 3D images with axial CT imaging improved the accuracy in classifying Borrmann type and tumor staging.

Adenocarcinoma↗

Bone bruises: MR characteristics and histological correlation in the young pig.

PURPOSE: To correlate magnetic resonance (MR) signal characteristics of bone bruises with histological findings. MATERIALS AND METHODS: In 14 tibiae of young pigs, bone bruises were created in the proximal tibial metaphysis. The signal intensity seen on the MR images were correlated with histological findings. The following findings were evaluated: (a) changes of signal intensity on the tibiae; (b) changes of histology on the tibiae; and (c) changes of (a) and (b) on follow-up examinations. RESULTS: We observed three types of injuries on T1-weighted images: focal or diffuse low signal, normal signal and linear low signal intensities. Severe hemorrhagic areas showed low signal intensities on all sequences of MR imaging. Fast spin-echo (FSE) T2-weighted images showed a more distinct low signal intensity than T1-weighted images. FSE short tau inversion recovery (STIR) and FSE fat saturated (FSE-FS) T2-weighted images showed similar signal intensities with FSE T2-weighted images. FS T1-weighted enhanced images showed low signal intensities with variable enhancements. Upon histological examination, hemorrhages and edemas were prominent at the subcortical areas of the contusion sites. The areas of dense, low signal intensities in all imaging sequences showed signs of severe hemorrhage. The areas of diffuse low signal and enhanced areas showed mixed areas of hemorrhages and edemas. Follow-up MR imaging showed evolution of the processes of hemorrhages and edemas with fatty marrow changes. CONCLUSIONS: MR imaging can depict changes in the bone marrow resulting from direct injury to the bone. MR imaging is a useful tool for evaluating the evolution of bone bruises.

Animals↗

Spiral CT of the gastric carcinoma: staging and enhancement pattern.

The purpose of this study was to correlate the preoperative staging of gastric carcinoma using spiral computed tomography (CT) with pathologic staging and to correlate the enhancement pattern of advanced gastric carcinoma (AGC) on spiral CT with histological type. A total of 180 patients with gastric carcinomas confirmed at surgery underwent spiral CT. After surgery, pathologic findings were compared with CT findings. The detection rate for T1 tumors was 81.4% (57/70), and all T2-4 tumors were detected (110/110). In the T class, good correlation with pathology occurred in 47.8%. In the N class, good correlation with pathology occurred in 52.2%. The rate of understaging in the N class (31.7%) was higher than that of overstaging (16.1%) (P<.001). In AGC, the tumor mass showed delayed enhancement, regardless of Borrmann's type. By histological pattern, good and delayed enhancement was seen in 2/3 (66.7%) with signet ring cell type, but 4/5 (80%) with mucinous type were poorly enhanced (P=.019). Spiral CT for determining the preoperative staging of gastric carcinoma was not accurate. However, the enhancement pattern of AGC correlated with histological type.

Adult↗

Comparison of hydro-US and spiral CT in the staging of gastric cancer.

The purpose of this study was to compare the diagnostic accuracy of hydro-ultrasonography (US) and spiral computed tomography (CT) in the staging of gastric cancer. Forty-three patients with gastric cancers confirmed at surgery underwent hydro-US and spiral CT on the same day prospectively. Hydro-US and spiral CT were done after ingestion of water. US and CT images were independently analyzed. After surgery, pathological findings according to TNM classification were compared with US and CT findings. The detection rate for T1 tumors was 75% (12/16), and all T2-T4 tumors were detected (27/27). In the T class, good correlation with pathology occurred in 55.8% of cases for US and 58.1% for CT, and there was no difference in staging accuracy between US and CT (P=.7667). Overstaging occurred in 14% for US and CT. Understaging occurred in 30.2% for US and 27.9% for CT. In the N class, good correlation with pathology occurred in 60.5% for US and 55.8% for CT, and there was no difference in staging accuracy between US and CT (P=.0949). Overstaging occurred in 4.7% for US and 18.6% for CT, and understaging occurred in 34.9% and 25.6%, respectively. The diagnostic accuracy of hydro-US and spiral CT in the staging of gastric cancer was between 55.8% and 60.5%, and there was no significant difference in staging accuracy between hydro-US and spiral CT, except for a tendency to overstaging by CT and understaging by US in the N class (P<.05).

Adult↗

The role of 3D spiral CT in early gastric carcinoma.

PURPOSE: The purpose of this study is to assess the role of 3D imaging using spiral CT for the detection and evaluation of early gastric carcinoma (EGC). METHOD: Thirty-one patients with EGC underwent 3D and axial imaging using spiral CT, and all cases were confirmed at surgery. According to the pathologic specimens, one patient (3.2%) had type I, five (16.1%) had type IIb, 13 (42.0%) had type IIc, three (9.6%) had types IIc + IIb, three (9.6%) had types IIc + III, two (6.5%) had types IIa + IIc, two (6.5%) had types IIb + IIc, and two (6.5%) had types IIb + III. Spiral CT was first performed with 3 mm collimation, 4.5 mm/s table feed, and a 1 mm reconstruction interval in the supine position after intravenous injection of Buscopan and ingestion of gas. The 3D shaded surface display renderings were performed, analyzed, and graded as excellent, good, or poor. Axial CT scanning was performed with 5 mm collimation, 7 mm/s table feed, and a 5 mm reconstruction interval in the prone position after ingestion of water. RESULTS: With use of axial CT images, 20 of 31 tumors (64.5%) were detected. Tumors were suspected in two cases, but nine were not detected. With use of 3D images, 29 of 31 tumors (93.5%) were detected (p < 0.05). Of the 31 cases of EGC, excellent 3D images were obtained in 6 patients (19.3%), good 3D images in 21 (67.7%), and poor 3D images in 2 (6.5%). In the two cases with poor images, the tumor was confined to the mucosal layer and the types were EGC IIc + IIb. In the remaining two cases (6.5%), the tumors were not detected by 3D images. In one case, the tumor was confined to the mucosal layer, and in the other it was located in the pyloric antrum. Both tumors were EGC type IIc. The two cases not detected by 3D imaging were also not detected by axial CT scanning. CONCLUSION: The detection rate of EGC is higher using 3D imaging than axial CT scan alone.

Adult↗