Search PubMed⌕ Search

Biomedical subjects

K C Cho

Publications and source records attributed to K C Cho.

At least 37 records · Page 2Linked to original sources

Bowel obstruction: evaluation with CT.

Eighty-four computed tomographic (CT) scans from patients referred for bowel obstruction between January 2, 1988, and December 31, 1989, were retrospectively evaluated. A pair of radiologists without knowledge of patient histories determined the presence or absence of bowel obstruction. Sixty-four patients ultimately proved to have intestinal obstruction, and 20 did not. Diagnosis was established by means of surgery (n = 39), barium studies (n = 17), and clinical course (n = 28). Causes of obstruction included adhesions (n = 37), metastases (n = 6), primary tumor (n = 7), Crohn disease (n = 4), hernia (n = 3), hematoma (n = 2), colonic diverticulitis (n = 2), and other (n = 3). In addition, 83 CT examinations in patients with no history or indication of intestinal obstruction were simultaneously reviewed. The overall sensitivity was 94%, specificity was 96%, and accuracy was 95%. The cause of obstruction was correctly predicted in 47 of 64 cases (73%). Intestinal obstruction was not diagnosed in any of the 83 control patients. CT is most useful in patients with a history of abdominal malignancy and in patients who have not been operated on and who have signs of infection, bowel infarction, or a palpable abdominal mass.

Barium Sulfate↗

Comparison of computed tomography and contrast enema evaluation of diverticulitis.

A total of 31 patients with diverticulitis were analyzed who had both computed tomography and contrast enema. There was almost equal sensitivity to abnormality of approximately 90 percent. Contrast enema produced a specific diagnosis of diverticulitis in 61 percent, using stringent positive criteria, and an additional 29 percent with suggestive findings. Comparative computed tomography specific diagnoses in those 31 cases was made in 65 percent, and suggestive in 23 percent. Computed tomography was particularly useful diagnostically in cases of retrograde obstruction on contrast enema. The authors conclude that contrast enema should be the primary mode of approach, while computed tomography can be a valuable follow-up when the diagnosis is still in doubt, or if it is possible that patient management might be altered by additional information.

Barium Sulfate↗

Sigmoid diverticulitis: diagnostic role of CT--comparison with barium enema studies.

The diagnostic value of computed tomography (CT) and barium enema (BE) studies was evaluated prospectively in hospitalized patients with the presumptive diagnosis of acute sigmoid diverticulitis based on the presence of left-lower-quadrant pain and tenderness, fever, and leukocytosis. Of 56 patients, 11 had sigmoid diverticulitis confirmed at surgery and 16 by clinical response to medical therapy. CT, performed in all diverticulitis patients, had positive results in 93% (25 of 27). These compared favorably with BE study results, of which 80% (20 of 25) were positive. Neither examination had false-positive results. In the 29 patients who did not have diverticulitis, an alternative diagnosis was made by means of CT in 20, but in only three by means of BE studies. Many of the extracolonic abnormalities recognized at CT were clinically unexpected and necessitated emergency surgery. The excellent sensitivity and specificity of CT coupled with its versatility in the detection of extracolonic disease give it an advantage over contrast enema studies for diagnosis of sigmoid diverticulitis. CT should be the initial study in acutely ill patients, especially when the clinical features are atypical for sigmoid diverticulitis.

Acute Disease↗

Electron transfer between cytochrome c and metal hexacyanide complexes. Effect of thermodynamic driving force on the electron transfer rate.

The electron transfer reactions between ferrocytochrome c and three isomorphic hexacyanide complexes, [Fe(CN)6]3-, [Os(CN)6]3- and [Ru(CN)6]3-, have been studied using the method of photoexcitation. The transfer rates for [Os(CN)6]3- and [Ru(CN)6]3- are, respectively, about 45- and 200-times higher than that of [Fe(CN)6]3-. A reorganization energy of approx. 0.8 eV was found for the cytochrome c-hexacyanide system when the data were analyzed according to the theory of Marcus.

Cyanides↗

Terminal ileitis associated with cytomegalovirus and the acquired immune deficiency syndrome.

A 41-yr-old homosexual male had cytomegalovirus infection localized to the terminal ileum as his initial and sole evident opportunistic infection due to the acquired immune deficiency syndrome. The symptoms, signs, roentgenographic findings, and appearance at surgery were suggestive of Crohn's disease. The pathogen was identified only by microscopic examination of bowel resected during a second laparotomy. The terminal ileum had profound mucosal ulceration and transmural fibrosis without granulomas. This novel report suggests that cytomegalovirus infection should be carefully searched for in immunocompromised patients presenting with clinical features suggesting Crohn's disease.

Acquired Immunodeficiency Syndrome↗

Colonic adenocarcinoma associated with the acquired immune deficiency syndrome.

Colonic adenocarcinoma developed in an intravenous drug abuser with the acquired immune deficiency syndrome (AIDS) that was diagnosed by the presence of antibodies to the human immunodeficiency virus (HIV), generalized lymphadenopathy, and biopsy proven esophageal candidiasis. The colon cancer presented atypically at a young age with no known risk factors and with a bulky primary tumor and a local fistula. AIDS and AIDS risk factors have been associated with Kaposi's sarcoma, lymphomas, and anal and oropharyngeal carcinoma. This report suggests a possible association between colonic adenocarcinoma and AIDS.

Acquired Immunodeficiency Syndrome↗

Kinetics of electron transfer between cytochrome c and iron hexacyanides. Evidence for two electron-transfer sites.

The electron-transfer reaction between ferrocytochrome c and ferricyanide has been studied by the method of photoexcitation. The observed transfer rate shows saturation behaviour at high ferricyanide concentration. Data analysis indicates that there are two binding sites of vastly different affinities at which electron transfer occurs. The binding constant for the strong binding site decreases from 1600 M-1 to 80 M-1 as the ionic strength increases from 15 mM to 140 mM. At 20 degrees C, the intramolecular electron-transfer rate for this site is 4.65 X 10(4) s-1, which gives an electron-transfer distance of approx. 9.7 A according to Hopfield's model.

Animals↗

Radiologic evaluation of pancreatic ascites.

Two cases of pancreatic ascites are presented in which preoperative endoscopic retrograde pancreatography (ERP) precisely identified the exact location of the leakage of pancreatic juice into the peritoneal cavity. Computed tomography was not helpful in either case. Endoscopic retrograde pancreatography is the most valuable imaging examination to confirm the diagnosis of pancreatic ascites and to direct surgical management.

Aged↗

Computed tomographic features of puerperal ovarian vein thrombosis.

Puerperal ovarian vein thrombosis is a dangerous complication of childbirth and often leads to inferior vena cava thrombosis and multiple pulmonary emboli. Computed tomography of the abdomen is useful in early diagnosis. Two patients with typical computed tomographic features are presented.

Adult↗

CT of peritoneal lymphomatosis.

The CT and clinical findings are presented in seven patients with diffuse peritoneal malignancy caused by non-Hodgkin lymphoma. All seven patients had CT evidence of ascites, omental infiltration, and peritoneal implants mimicking carcinomatosis. Bulky retroperitoneal or mesenteric adenopathy was present in only one patient. Four of the seven patients had documented AIDS. Paracentesis provided a diagnosis of lymphoma in only one of the seven patients. In the other six patients, the final diagnosis was established by surgery (three patients), by autopsy (one patient), by laparoscopy (one patient), and by guided needle aspiration (one patient). Although uncommon, lymphoma should be considered in patients who have diffuse peritoneal malignancy, particularly those who are at risk for AIDS.

Acquired Immunodeficiency Syndrome↗

Multiple transverse folds in the gastric antrum.

Fine transverse folds of the esophagus are well described as a transient motor phenomenon seen in patients with or without gastroesophageal reflux. They appear to be due to contraction of the muscularis mucosa and are thought to have little, if any, significance. We have observed similar transverse folds in the gastric antrum during double-contrast upper gastrointestinal series in five patients. In contrast to the transient nature of the folds in the esophagus, these gastric folds were more persistent. They were seen in multiple spot images with the gastric antrum distended or partially collapsed and even during peristalsis. In follow-up studies, the folds were repeatedly demonstrated in two patients. Two patients had associated gastric polyps with histologic evidence of chronic gastritis; however, the antral mucosa appeared normal on endoscopy. The remaining three patients had no associated gastric disease. The pathophysiologic significance of these folds is yet to be determined; however, they appear to be clinically insignificant.

Adult↗

Cytomegalovirus esophagitis in AIDS: radiographic features in 16 patients.

Cytomegalovirus is one of the more common opportunistic organisms implicated in the development of esophagitis in patients with AIDS. A review of the radiographic features of 16 proved cases of cytomegalovirus esophagitis showed a spectrum of abnormalities related to the severity of the inflammatory process. Seven patients had a mild form of esophagitis with segmental involvement characterized by granular mucosa, superficial erosions, and poorly defined, shallow ulcerations. Nine patients had more severe esophagitis with solitary or multiple deep ulcers and a background of normal mucosa. The deep ulcerations were oval in shape and varied in size. Some projected intraluminally and had a thin rim of radiolucency at the base. Short-term follow-up examinations showed progression of the disease in four patients, no change in one patient, and regression without specific therapy in one patient. Although these radiographic features are highly suggestive of cytomegalovirus esophagitis, the diagnosis requires histologic confirmation.

Acquired Immunodeficiency Syndrome↗

Adiabatic compressibility of myoglobin. Effect of axial ligand and denaturation.

An ultrasonic technique has been employed to study the adiabatic compressibility of three metmyoglobin derivatives (aquomet-, fluoromet- and azidometmyoglobin) at neutral pH, and aquometmyoglobin as a function of pH in the frequency range of 1-10 MHz at 20 degrees C. No difference was observed in the adiabatic compressibility of the various derivatives. This indicates that the binding of different axial ligands to myoglobin does not affect significantly the conformational fluctuations of the protein. The finding is consistent with the results of the hydrogen exchange rate experiment, indicating that both types of measurements are useful for the study of protein dynamics. Upon acid-induced denaturation, the adiabatic compressibility of myoglobin drops from 5.3 X 10(-12) cm2/dyn to 0.5 X 10(-12) cm2/dyn. Plausible reasons for such a decrease are discussed.

Animals↗