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Biomedical subjects

C S Wu

Publications and source records attributed to C S Wu.

At least 91 records · Page 5Linked to original sources
PubMed1993

Ganglioneuroma of the duodenum. Report of a case and literature review.

A 43-year-old male presented with upper gastro-intestinal bleeding. A polypoid tumor mass in the second part of the duodenum was found by endoscopic examination. Pathology revealed an extremely rare case of ganglioneuroma. The surgical local resection of the tumor was a sufficient procedure because of a lack of malignant potential. This is the fourth case since the first case was reported by Dahl et al in 1957 (1). We review the literature concerning duodenal paragangliomas, and discuss the histogenesis.

Adult↗
PubMed1993

[Acute upper gastrointestinal bleeding in Chang Gung Memorial Hospital: comparison between 1980 and 1989].

Upper gastrointestinal (UGI) bleeding remains a great medical problem despite the improvement in both diagnostic and therapeutic management. We retrospectively analyzed 560 cases (male 429 cases, female 131 cases, mean age 45.8 +/- 23.1 years) of acute UGI bleeding within one year from January to December 1980, and 1872 cases (male 1395 cases, female 477 cases, mean age 48.7 +/- 27.5 years) within one year from January to December 1989, in order to define the changing pattern of etiology in the past 10 years. The major cause of bleeding was duodenal ulcer bleeding, which occurred at the age of 20-40 years. The incidence significantly decreased (57.8% in 1980 VS. 46.3% in 1989, P < 0.001). The second common cause was gastric ulcer (11.1% VS. 13.5%), which occurred mainly at the age of 50-70 years. The third was esophageal varices bleeding with a significantly increased incidence (6.6% VS. 11.4%, P < 0.001), which occurred mainly at the age of 40-60 years. The other less common causes included gastric cancer (5.9% VS. 5.8%), which occurred mainly at the age of 50-70 years, gastric erosion (5.2% VS. 6.1%), Mallory Weiss tear (2.1% VS. 3.1%), esophagitis (1.9% VS. 2.9%), Dieulafoy's ulcer (1.6% VS. 2.7%), vascular lesion (1.6% VS. 2.6%), and non-diagnostic cases (6.2% VS. 5.6%). The ratio of male to female for each etiology of UGI bleeding was about 3 to 1 in both 1980 and 1989.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Hepatolithiasis, a clinical study.

Ninety-seven hepatolithiasis cases were reviewed retrospectively. Primary hepatolithiasis was about equal in both sexes, with most patients under 39 years of age. Most secondary hepatolithiasis patients who were female-predominant, were older than 40. Common presenting symptoms were abdominal pain, either epigastric or right upper quadrant of abdomen as noted in 93%; chills and fever in 70%; nausea and vomiting in 49.5%; jaundice was noted only in 39% of the patients. Blood tests showed elevation of alkaline phosphatase in 79.8%, and gamma-GT in 88.3%. Left branch involvement was much more common that right. Escherichia coli (E. coli) was the main organism isolated in most of the cases. Abdominal ultrasonography reached a diagnostic rate of 91.01%, and the condition could be missed in cases of intrahepatic muddy stones, pneumobilia and misidentification of the location of the stones. Endoscopic retrograde cholangiography (ERC) showed a clearer picture of the biliary tree, but failed in cases of distorted anatomy because of previous operation, stones impacted in the ampulla orifice, presence of diverticulum or poor opacification of the bile duct because of stricture or stone impaction.

Adolescent↗
PubMed1993

Eosinophilic gastroenteritis: 10 years experience.

Eight patients (five men, three women), mean age 36.9 +/- 13.5 (17-60) yr, were diagnosed to have eosinophilic gastroenteritis. The condition was proved in five patients by biopsies through endoscope, and in three, by operation. All had hypereosinophilia (absolute eosinophil count of 1,337-21,787/cm3). According to Klein classification, two had mucosal disease, three had muscle layer disease, and three, subserosal disease. The most common symptoms were abdominal pain (100%), diarrhea (62.5%), vomiting (62.5%), and nausea (50%). Four patients (50%) had symptoms for more than 1 yr before diagnosis. Barium studies revealed mucosal edema and/or thickening of the small intestinal wall in three cases (including one case with ulceration), partial gastric outlet obstruction in one case, and narrowing of lumen of the terminal ileum in one case. Hypotonic duodenogram revealed double contour in one case. Ultrasound examination revealed thickening of the intestinal wall in two cases; computer tomography revealed thickening of the intestinal wall in one case. All patients were treated with steroid (40 mg/day for initial dose and relapse; 5-10 mg/day for maintenance). The symptoms subsided and the eosinophil counts returned to normal within 2 wk in seven patients and 1 month in one. Of six patients being followed up for 2-10 yr, one had remission, four needed small maintenance dose of steroid, and one suffered from relapse with intestinal perforation.

Adolescent↗
PubMed1992

Beta-II conformation of all-beta proteins can be distinguished from unordered form by circular dichroism.

The CD spectrum of certain all-beta globular proteins resembles that of unfolded proteins with a characteristic negative band around 200 nm. The conformation of this class is tentatively termed beta-II, which had two features that were absent for unfolded proteins. First, beta-II proteins usually had CD bands due to aromatic side groups in the near-ultraviolet region. Second, the CD intensities both in the far- and in the near-uv region of these compact and rigid proteins usually showed a sharp transition upon thermal denaturation, whereas those of an unordered form changed linearly with rising temperature.

Chymotrypsin↗
PubMed1992

Solution structure and dynamics of epidermal growth factor and transforming growth factor alpha.

Circular dichroism (CD) and Fourier transform infrared spectroscopic studies have shown that the secondary structure of transforming growth factor alpha (TGF-alpha) is very similar to that of epidermal growth factor (EGF). The infrared spectra revealed a minor difference between the two proteins, in particular in the beta-sheet structure. A large difference was observed with CD between the two proteins in the apparent conformation each adopts when the disulfide bonds are reduced. Reduced TGF-alpha showed a distinct alpha-helical conformation only at a high trifluoroethanol concentration, whereas reduced EGF assumed an alpha-helical conformation in the absence of trifluoroethanol. This indicates that these two proteins adopt different secondary structures in the absence of disulfide bonds, although they assume similar folding structures in their presence. These data suggest that the disulfide bonds to a large degree dictate the conformation of these two proteins. Additionally, differences in the dynamic behavior between EGF and TGF-alpha were also observed. Infrared experiments showed that the hydrogen-deuterium exchange rate is much higher for TGF-alpha than for EGF, indicating that TGF-alpha is a more flexible molecule. The rate of reduction of the disulfide bonds by dithiothreitol was also faster for TGF-alpha. Therefore, it can be concluded that although EGF and TGF-alpha have a similar overall conformation, TGF-alpha is a more flexible molecule than EGF.

Circular Dichroism↗
PubMed1992

Conformational stability of porcine serum transferrin.

The conformation of porcine serum ferric transferrin (Tf) and its stability against denaturation were studied by circular dichroism. Tf was estimated to have 19-24% alpha-helix and 50-55% beta-sheet based on the methods of Chang et al. (Chang, C.T., Wu, C.-S.C., & Yang, J.T., 1978, Anal. Biochem. 91, 13-31) and Provencher and Glöckner (Provencher, S.W. & Glöckner, J., 1981, Biochemistry 20, 33-37). Removal of the bound ferric ions (apo-Tf) did not alter the overall conformation, but there were subtle changes in local conformation based on its near-UV CD spectrum. The Tfs were stable between pH 3.5 and 11. Denaturation by guanidine hydrochloride (Gu-HCl) showed two transitions at 1.6 and 3.4 M denaturant. The process of denaturation by acid and base was reversible, whereas that by Gu-HCl was partially reversible. The irreversible thermal unfolding of Tfs began at temperatures above 60 degrees C and was not complete even at 80 degrees C. The bound irons (based on absorbance at 460 nm) were completely released at pH < 4 or in Gu-HCl solution above 1.7 M, when the protein began to unfold, but they remained intact in neutral solution even at 85 degrees C. The NH2- and COOH-terminal halves of the Tf molecule obtained by limited trypsin digestion had CD spectra similar to the spectrum of native Tf, and the COOH-terminal fragment had more stable secondary structure than the NH2-terminal fragment.

Animals↗
PubMed1992

Conformation of concanavalin A and its fragments in aqueous solution and organic solvent-water mixtures.

The conformations of concanavalin A (con A), an all-beta protein, and its three CNBr-cleaved fragments were studied by CD. Con A in buffer showed a 197 nm maximum and a 223 nm minimum, which were red-shifted by 6-7 nm from those of regular all-beta proteins and beta-sheet of (Lys)n. Fragment 1 (residue 1-42) resembled an unordered form with a CD maximum at 200 nm, but fragments 2 (residues 43-129) and 3 (residues 130-237) showed a regular CD spectrum with two extrema at 192-193 nm (+) and 214-216 nm (-). Equimolar mixture of the three fragments showed some degree of interaction, but did not reconstitute the conformation of native con A, probably because of the loss of bound Ca2+ and Mn2+ ions in the fragments. In ethanol-, methanol-, and dioxane-water mixed solvents, con A and its fragments remained as beta-sheet. In contrast, addition of trifluoroethanol and sodium dodecyl sulfate induced alpha-helix at the expense of beta-sheet for con A and its fragments in aqueous solution. In 80% trifluoroethanol, the induced helicities exceeded their sequence-predicted helix-potentials, but in 10 mM sodium dodecyl sulfate the helicities agreed well with corresponding predictions.

Buffers↗
PubMed1992

Computed tomographic finding in adenomyomatosis of the gallbladder.

We report on an uncommon case of symptomatic generalized adenomyomatosis of the gallbladder. It was initially suspected by ultrasonography and further confirmed by computed tomography (CT). A postcontrast CT scan at the level of the gallbladder body demonstrated the characteristic rosary sign. The rosary sign is formed by the enhanced proliferative mucosal epithelium with the intramural diverticula surrounded by the unenhanced hypertrophied muscle coat of the gallbladder. Similar CT scans were obtained sequentially in the caudal direction. These CT scan findings indicated generalized adenomyomatosis of the gallbladder. The patient received a cholecystectomy. The pathologic report showed specific changes of adenomyomatosis corresponding to the findings on the CT scan. Generalized adenomyomatosis of the gallbladder, therefore, can be accurately diagnosed by CT.

Adult↗
PubMed1992

Herpes esophagitis: a cause of upper gastrointestinal bleeding in an immunocompetent patient.

Herpes esophagitis presents as dysphagia and odynophagia in the majority of cases. Rarely has hematemesis been reported. We report a case of herpes esophagitis presenting with hematemesis in an immunocompetent patient. This 67-year-old man suffered from herpes esophagitis, proven by a panendoscopic examination, with characteristic histological findings. He presented with hematemesis and passage of tarry stools, but was otherwise healthy with normal humoral, cell-mediated immunity and was negative for human immunodeficiency virus antibody. Only supportive treatment was given. He has been well for the past nine months since the initial diagnosis.

Aged↗
PubMed1992

Adjunctive choledochoduodenostomy to choledocholithotomy in the treatment of calculous biliary tract disease.

Between 1986 and 1991, 16 selected patients with calculous biliary tract disease (CBTD) underwent side-to-side choledochoduodenostomy (CDS) as an adjunct to either primary (10 patients) or secondary (six patients) choledocholithotomy. Patients selected for adjunctive CDS were those with common bile duct dilatation > or = 1.5 cm in size. All operations were elective procedures. The stoma of the CDS was about 3.0 cm in size, measured directly. There were no operative deaths. There were no early complications related to the CDS procedure itself, except for two (12.5%) wound infections. CDS significantly eliminates bile stasis which is indicated by a fall in both the serum levels of alkaline phosphatase (from 228 +/- 118 to 72 +/- 22 IU/L, p < 0.01) and total bilirubin (from 4.7 +/- 4.7 to 0.9 +/- 0.2 mg/dL, p < 0.01) postoperatively. Late complications (ascending cholangitis or sump syndrome) of CDS or recurrent symptoms of CBTD were not encountered during the average follow-up period of 21 +/- 18 months. From our clinical results, we suggest that adjunctive CDS to choledocholithotomy is a safe and effective procedure in the treatment of selected patients with CBTD.

Adult↗
PubMed1992

Retrograde jejunogastric intussusception caused by a jejunal polyp.

A 70-year-old male presented with epigastric pain, vomiting and upper gastrointestinal bleeding 11 years after a subtotal gastrectomy. Retrograde jejunogastric intussusception was diagnosed by endoscopy and barium meal study and finally confirmed by laparotomy. After reduction of the intussusception, a small polyp was found at 20 cm distal to the anastoma, which served as the leading point of intussusception. The pathophysiology and clinical manifestations of this disease were reviewed.

Aged↗
PubMed1992

Gastric adenocarcinoma simulating benign gastric ulcer.

The pathologic features and prognosis of patient in whom gastric cancer simulates at endoscopy as a benign gastric ulcer has been poorly characterized. We performed a retrospective study with particular reference to the long term prognosis on 191 patients treated for gastric adenocarcinoma over the period 1980-1986. In 176 of these 191 patients (92.2%), the endoscopic findings suggested cancers, while in the remaining 15 patients (7.8%), the endoscopic appearance suggested benign ulcer. Comparing gastric cancers masquerading as benign gastric ulcers with those appeared malignant endoscopically, the former had higher resectability rate (100% vs 77.3%), higher incidence of early gastric cancer (73.3% vs 6.25%), less poorly differentiated carcinoma (33.3% vs 65.4%), less lymph node metastasis (13% vs 69.5%) and a higher five-year survival rate (86.6% vs 24.8%) (p less than 0.05 in all). Our study indicated that gastric adenocarcinomas simulated benign gastric ulcers at endoscopy are mostly early gastric cancers that carry a much better prognosis.

Adenocarcinoma↗
PubMed1991

Some problems of CD analyses of protein conformation.

The circular dichroic (CD) spectra of 16 reference proteins were analyzed by the Provencher-Glöckner method (Biochemistry 20, 31, 1981) with the lower-wavelength limit raised from 190 to 235 nm at 5-nm intervals. Fifty-one data points at 1-nm intervals were taken between 190 and 240 nm. Variations of the correlation coefficients (r) and root-mean-square (RMS) deviations between X-ray diffraction results and CD analyses showed no definite trend with shorter wavelength ranges. The CD spectra (190-240 nm) were also analyzed by assigning the secondary structure of X-ray results according to the Levitt-Greer method (J. Mol. Biol. 114, 181, 1977) and the Kabsch-Sander method (Biopolymers 22, 2577, 1983). The r and RMS values based on the Levitt-Greer assignment were good and comparable to those based on the secondary structure given by crystallographers, but the Kabsch-Sander assignment seemed to give unsatisfactory results. The choice of reference proteins remains one of the uncertainties in the CD analysis. The five most significant orthogonal spectra (190-240 nm) calculated from the 16 reference proteins and those based on another 16 proteins used by Hennessey and Johnson (Biochemistry 20, 1085, 1981) were similar to each other, but different in intensities. These methods still cannot recognize a failed analysis of unknown proteins without X-ray results to check their reliability.

Circular Dichroism↗
PubMed1991

Basic fibroblast growth factor is a beta-rich protein.

The conformation of the 153-residue form of human basic fibroblast growth factor (bFGF) was studied with circular dichroism (CD) and sequence prediction methods. The far-UV CD spectrum with a minimum at 202 nm resembled that of an unordered polypeptide/protein or a protein rich in distorted antiparallel beta-sheets. Analysis of the CD spectrum by the least-squares method of Chang et al. (1978) and the CONTIN program of Provencher and Glöckner (1981) suggested that about one half of the molecule consisted of beta-sheet and there was no alpha-helix. These estimates agreed with the prediction by the sequence method of Garnier et al. (1978) using decision constants based on CD results. bFGF had an unusual CD band at 187 nm, which disappeared upon ionization of Tyr side chains at pH 11.7. It also had another unusual property of irreversibly converting the CD spectrum to a helix-like one with a double minimum at 205 and 215 and a maximum at 189 nm upon heating the solution to above 55 degrees C. The helicity was also enhanced in trifluoroethanol and in sodium dodecyl sulfate. The mutant bFGF in which cysteines 76 and 94 were replaced by serine residues had essentially the same properties as the wild-type.

Amino Acid Sequence↗
PubMed1991

Risk factors for perforation of gallbladder. A combined hospital study in a Chinese population.

The composition and location of gallstones differ in Western and Eastern people. This has been documented in the literature. The difference in the clinical manifestations of biliary calculous disease has been postulated to be based on ethnic or environmental factors. In an effort to improve our management of patients with gallbladder perforations, a combined hospital study in a Chinese population during 11 years was conducted to study the clinical profiles at risk. Seventy-one patients were studied. The perforations were categorized as either acute (type I) in 14 (19.7%), subacute (type II) in 25 (35.2%), or chronic (type III) in 32 (45.1%). The incidence of severe underlying disease was significantly greater (p = 0.02) in patients with acute and subacute perforation as compared with chronic perforation. Multiple stones in the biliary tree and the gallbladder are very common and may mask the presentation of gallbladder perforation when patients with either biliary colic or biliary tract infection. A history suggestive of chronic gallstone disease is common, especially in patients with chronic perforation. The clinical manifestations of gallbladder perforation are similar to those of acute cholecystitis without perforation. On the basis of these data, clinical profiles have been developed for patients at risk of developing acute versus chronic gallbladder perforation. Awareness of these groupings forms the basis for early recognition and treatment of acute gallbladder perforation.

Acute Disease↗
PubMed1991

[Pseudomembranous colitis: a clinical analysis and review of literatures].

Clostridium difficile has been well known to be a pathogen of pseudomembranous colitis. It is characterized by the formation of elevated plaques and pseudomembranes which result in varying degree of diarrhea. This series analysed 20 cases of pseudomembranous colitis diagnosed at Chang Gung Memorial Hospital between January 1985 and December 1989. The male to female ratio was 1:3. Their ages ranged between 13 and 81 years, with a mean of 53.7 years. Sixteen of our patients claimed to have taken antibiotics for upper respiratory tract infection, pneumonia, cellulitis or acute pelvic inflammatory disease within six weeks before onset of symptoms. The antibiotics were mainly in the penicillin group and cephalosporin group. Clinical presentations included diarrhea of varying degree, fever, and abdominal pain. The diagnosis was made by the typical colonic mucosal changes under sigmoidoscopic or colonoscopic examination and pathological findings. The lesions were prominent in the rectum and sigmoid colon. Eleven cases were treated with vancomycin. Of these, one failed and died, and two recurred. The two recurrences were again treated with the same dose of vancomycin and with complete remission. Three of our patients responded to metronidazole. The other six cases with milder symptoms were successfully controlled by using cholestyramine (2 cases) or by supportive treatment (4 cases).

Adolescent↗