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C S Wu

Publications and source records attributed to C S Wu.

At least 55 records · Page 3Linked to original sources
PubMed1997

Identification of putative c-Myc-responsive genes: characterization of rcl, a novel growth-related gene.

The c-Myc protein is a helix-loop-helix leucine zipper oncogenic transcription factor that participates in the regulation of cell proliferation, differentiation, and apoptosis. The biochemical function of c-Myc has been well described, yet the identities of downstream effectors are just beginning to emerge. We describe the identification of a set of c-Myc-responsive genes in the Rat1a fibroblast through the application of cDNA representational difference analysis (RDA) to cDNAs isolated from nonadherent Rat1a and Rat1a-myc cells. In this system, c-Myc overexpression is sufficient to induce the transformed phenotype of anchorage-independent growth. We identified 20 differentially expressed cDNAs, several of which represent novel cDNA sequences. We further characterized one of the novel cDNAs identified in this screen, termed rcl. rcl expression is (i) directly stimulated by c-Myc; (ii) stimulated in the in vivo growth system of regenerating rat liver, as is c-myc; and (iii) elevated in human lymphoid cells that overexpress c-myc. By using an anti-Rcl antibody, immunoblot analysis, and immunofluorescence microscopy, the Rcl protein was found to be a 23-kDa nuclear protein. Ectopic expression of the protein encoded by the rcl cDNA induces anchorage-independent growth in Rat1a fibroblasts, albeit to a diminished extent compared to ectopic c-Myc expression. These data suggest a role for rcl during cellular proliferation and c-Myc-mediated transformation.

Amino Acid Sequence↗
PubMed1997

Ménétrier's disease: a new variant with duodenal involvement.

Ménétrier's disease is a rare cause of hypertrophic gastropathy, usually confined to gastric body and fundus, which is characterized by giant rugae, hypoalbuminemia, and foveolar hyperplasia. The etiology of this disease is still unknown. We report a case of a 74-yr-old man who had dyspepsia, hypoalbuminemia, weight loss, and diffuse polypoid, nodular lesions affecting the whole stomach and proximal duodenum on gastroscopy and barium meal study. The histology of gastric and duodenal mucosal lesions fulfilled the diagnosis of Ménétrier's disease, that was not described to involve duodenum in the literature. The disease resolved clinically, endoscopically, and pathologically after therapy with famotidine for 3 months. We speculated that extensive pyloric metaplasia and then foveolar hyperplasia of duodenum in this patient might be a variant of Ménétrier's disease with favorable clinical course.

Aged↗
PubMed1997

Gastric adenocarcinoma with microangiopathic hemolytic anemia and disseminated intravascular coagulation: a case report.

The case reported was a 54-year-old woman with adenocarcinoma of the stomach who developed microangiopathic hemolytic anemia (MHA) and disseminated intravascular coagulation (DIC). Clinical and laboratory data pertaining to this patient are presented. The patient died of multiple organ failure on the 12th hospital day. Since 1962, a total of 96 cases of MHA occurring in patients with malignancy have been reported. About half of them occurred in patients with gastric carcinoma. The possible pathogenesis of MHA and disseminated intravascular coagulation in patients with gastric adenocarcinoma is discussed.

Adenocarcinoma, Mucinous↗
PubMed1997

Factors affecting delection of bleeding lesions in the stomach by initial emergency endoscopy.

BACKGROUND: Accurate endoscopic diagnosis of acute gastric bleeding can be problematic and missing diagnoses are not uncommon. However, the causes of diagnostic difficulty and the most common locations of bleeding resulting in missed diagnosis are not well known. METHODS: To determine the causative factors of incomplete study, we analyzed the medical records and performed follow-up on 64 patients for whom initial emergency endoscopy had failed to identify the sites of acute gastric bleeding. The bleeding sites were confirmed by the findings of subsequent endoscopic examination or operation in these cases. RESULTS: Excessive blood covering the examination field was the most frequent cause of incomplete endoscopic study (60/64). Underlying gastric lesions which were later identified as sources of gastric bleeding included: 30 gastric ulcers, 9 gastric varices, 6 acute gastric mucosal lesions, 3 Dieulafoy's lesions, 3 portal hypertensive gastropathies, 2 gastric tumors, 1 Mallory-Weiss tear and 2 unidentified bleeding sites. Eight patients refused further evaluation. The locations of the bleeding sites included: 1 esophagocardiac junction, 8 cardia, 5 fundus, 21 body, 9 antrum, 7 stoma, 3 diffuse pattern. The 42-day mortality rate of these patients was 20%. Of these patients, decompensated liver cirrhosis (8/13) and hepatic failure (7/13) were the most common underlying diseases. CONCLUSION: Inadequate preparation was the most frequently procedural problem associated with missed diagnosis. Lesions located in the body of the stomach were most likely to go undiagnosed. Gastric ulcers were the most common type of unidentified bleeding ulcer site. Hepatic failure was the most common cause of death. The high mortality rate of these patients appeared to be related to underlying diseases rather than to the nature of the lesions responsible for gastric bleeding.

Adult↗
PubMed1997

Abnormal bcl-2 and pRb expression are independent correlates of radiation response in muscle-invasive bladder cancer.

The objective of this study was to determine whether the overexpression of bcl-2, a key protein governing the apoptotic response to radiation, adds to pRb status in estimating the propensity for radiation response in patients with muscle-invasive bladder cancer. Archival formalin-fixed, paraffin-embedded, pretreatment bladder tumor samples were available in 109 of 301 patients treated preoperatively with 50 Gy in 25 fractions followed by radical cystectomy 4-6 weeks later. Radiation response was assessed by clinical-to-pathological tumor downstaging or upstaging. Altered expression of bcl-2 (47% of 107 patients), p53 (56% of 109 patients), and pRb (30% of 98 patients) was assessed by immunohistochemical staining. Morphological criteria were used to calculate the percentage of apoptotic cells. bcl-2 staining correlated with tumor grade; all grade 2 tumors (n = 7) displayed normal bcl-2 expression (negative staining). No correlations between bcl-2 staining and pretreatment apoptosis levels, p53 staining, and pRb staining were observed. In terms of the radiation response parameters, univariate analyses revealed that bcl-2 overexpression was the only factor associated with upstaging. The main predictor of downstaging was the loss of pRb expression (negative staining). Multivariate logistic regression confirmed these findings and also showed that normal pRb expression (positive staining) was significantly related to upstaging. Patient outcome was adversely affected by bcl-2 overexpression, because these patients experienced significantly increased actuarial local failure rates. No difference in distant metastasis or survival rates by bcl-2 staining was seen. The strongest independent correlates of radiation response thus far identified in muscle-invasive bladder cancer are from bcl-2 and pRb immunohistochemical staining. The overexpression of bcl-2 and the normal expression of pRb seem to thwart the apoptotic response to radiation via independent mechanisms. Abnormalities in the expression of proteins that regulate apoptosis may prove to establish a molecular phenotype to characterize which patients should receive radiotherapy.

Actuarial Analysis↗
PubMed1996

Carboxy-terminal CVLS-sequence-specific protein farnesyltransferase from the eyes of the shrimp Penaeus japonicus: purification and characterization.

Protein farnesyltransferase from the eyes of Penaeus japonicus farnesylates predominantly H-ras-specific carboxyl termini, with the sequence CVLS, but not the K-ras-specific sequence CVIM or the protein geranylgeranyltransferase-specific sequence CAIL. The purified protein farnesyltransferase from shrimp was found by immunoblotting and polyacrylamide gel electrophoresis under denaturing conditions to consist of subunits of Mr 49,000 and Mr 48,000. Since the active protein farnesyltransferase was found to have a relative mass of 100,000, the purified enzyme was deduced to be a heterodimer. The enzyme had an optimal pH of 6 and a K(m) of 14 +/- 1 microM with the synthetic peptide RTRCVLSH as the substrate. The enzyme was activated by Mn+2 and Mg+2 but inhibited by Ca+2 ions.

Alkyl and Aryl Transferases↗
PubMed1996

A link between c-Myc-mediated transcriptional repression and neoplastic transformation.

Recent studies indicate that the transcription factor c-Myc contributes to oncogenesis by altering the expression of genes involved in cell proliferation, but its precise function in neoplasia remains ambiguous. The ability of c-Myc to bind the sequence CAC(G/A)TG and transactivate appears to be linked to its transforming activity; however, c-Myc also represses transcription in vitro through a pyrimidine-rich cis element termed the initiator (Inr). In transfection experiments using the adenoviral major late (adML) promoter, which contains two Myc binding sites and an Inr, we determined that c-Myc represses transcription through the initiator in vivo. This activity requires the dimerization domain and amino acids 106 to 143, which are located within the transactivation domain and are necessary for neoplastic transformation. We studied a lymphoma-derived c-Myc substitution mutation at 115-Phe, which is within the region required for transcriptional suppression, and found the mutant more effective than wild-type c-Myc in transforming rodent fibroblasts and in suppressing the adML promoter. Our studies of both loss-of-function and gain-of-function c-Myc mutations suggest a link between c-Myc-mediated neoplastic transformation and transcriptional repression through the Inr.

Animals↗
PubMed1996

Identification of immunodominant, group-specific and subcomplex-specific, continuous epitopes in the core regions of Japanese encephalitis virus using synthetic peptides.

Two flaviviruses, Japanese encephalitis (JE) virus and Dengue (DEN) virus which have high pathogenicity for humans, continue to pose a serious public health problem in tropical and subtropical countries of the world. In order to identify the immunodominant B-cell epitopes for diagnostic application, we have prepared a series of 15-mer synthetic peptides from JE virus core protein based on computer analysis. Four linear, immunodominant epitopes corresponding to amino acids 91-105 (P78), 1-15 (P73), 8-22 (P74), and 34-48 (P75) of JE virus core proteins were identified by employing an enzyme-linked immunosorbent assay (ELISA), using high-titered immune sera from JE-vaccinated children. P78 was found to be the most immunodominant. The sero-specificity of these peptides was tested by binding to seroconverted samples from JE and DEN-1 patients. P78 and P74 belonged to group-specific epitopes which reacted with both JE and DEN-1 patient sera. P73 and P75 belonged to subcomplex-specific epitopes which reacted only with JE but not with DEN-1 patient sera. The study suggests that these peptides corresponding to the immunodominant epitopes of JE virus core protein might have the potential to be used as peptide-based diagnostic reagents for the detection and differentiation of JE and DEN antibody responses.

Adult↗
PubMed1996

Gastrointestinal bleeding after hepatic transcatheter arterial embolization in patients with hepatocellular carcinoma.

BACKGROUND: Transcatheter arterial embolization is a popular palliative treatment for patients with hepatocellular carcinoma, but the incidence of post-treatment gastrointestinal bleeding is not well-defined. METHODS: We retrospectively analyzed 206 patients with hepatocellular carcinoma who received transcatheter arterial embolization and compared them with 193 patients with hepatocellular carcinoma who underwent angiography along. RESULTS: Twenty-three episodes (8.5%) of gastrointestinal bleeding occurred within 3 months of hepatic transcatheter arterial embolization following 269 procedures involving 206 patients with hepatocellular carcinoma. Eight episodes (3.0%) of esophageal variceal bleeding and 15 episodes (5.5%) of nonvariceal bleeding were found. The sites of the nonvariceal bleeding episodes were the stomach (n = 7), duodenum (n = 5), and colon (n = 3). When compared with other sources, bleeding from esophageal varices took place earlier, required intensive treatment, and led to a higher mortality. Among another 193 patients with hepatocellular carcinoma who received angiography only, 6 patients developed gastrointestinal bleeding within 3 months (3.1%), and all bled from esophageal varices. CONCLUSIONS: This study suggests that esophageal variceal bleeding may occur after both angiography and transcatheter arterial embolization. Nonvariceal bleeding episodes, which were usually milder than episodes of variceal bleeding, may be related to the embolization procedure itself.

Adolescent↗
PubMed1996

Prognostic value of p53 in muscle-invasive bladder cancer treated with preoperative radiotherapy.

OBJECTIVES: The relationship of p53 mutations as analyzed immunohistochemically to radiation response and therapeutic outcome was examined in a cohort of 301 patients with muscle-invasive transitional cell carcinoma of the bladder treated relatively uniformly with preoperative radiotherapy (50 Gy in 25 fractions) 4 to 6 weeks prior to radical cystectomy. METHODS: Adequate formalin-fixed paraffin-embedded archival tissue for the immunohistochemical staining of p53 using antibody DO1 was obtained in 109 patients. The median follow-up for those living was 91 months. RESULTS: Overall, p53 staining was positive in 56% of the cases, with 60% positive in Stage T2 (n = 48), 42% in Stage T3a (n = 31), and 63% in Stage T3b (n = 30). Overexpression of p53 did not correlate with actuarial local control, distant metastasis freedom, disease freedom, or overall survival. However, significant associations were seen when these analyses were limited to patients with clinical Stage T3b disease. In this subgroup, the actuarial 5-year rates for patients with p53 positively and negatively stained tumors were 55% and 100%, respectively, for distant metastasis freedom (P = 0.01), 51% and 91% for disease freedom (P = 0.04), and 32% and 91% for overall survival (P = 0.006). Cox proportional hazards models that included p53 staining and other prognostic factors of significance in the univariate analyses revealed p53 to be independently predictive of survival for patients with Stage T3b disease. CONCLUSIONS: The prognostic value of p53 immunostaining rested with Stage T3b patients. Although no correlations were found with radiation response, p53 positivity in this subgroup was associated with a higher rate of distant metastasis and reduced overall survival. For these patients, p53 negativity would indicate that aggressive local treatment (that is, preoperative radiotherapy and cystectomy) is sufficient, whereas p53 positivity would indicate that multiagent chemotherapy is required because of the increased risk of distant metastasis.

Carcinoma, Transitional Cell↗
PubMed1996

Prospective, randomized trial of hypertonic glucose water and sodium tetradecyl sulfate for gastric variceal bleeding in patients with advanced liver cirrhosis.

BACKGROUND AND STUDY AIMS: Information about the appropriate endoscopic treatment of gastric variceal bleeding is sparse. We therefore designed a prospective and randomized study to evaluate and compare efficacy and complication rates of two agents, hypertonic glucose water (50% GW) and sodium tetradecyl sulfate (STS), in treating acute gastric variceal bleeding after esophageal varix eradication. PATIENTS AND METHODS: Of 51 patients with advanced cirrhosis of the liver (Child's C), with acute gastric variceal bleeding initially evaluated, 25 patients were randomized to receive 1.5% STS and 26 to receive 50% glucose water. Treatment was aimed at achieving initial and permanent hemostasis by variceal eradication. RESULTS: Control of acute gastric variceal bleeding was achieved in 80% of the STS group and 92% of the GW group. The rebleeding rate in the STS group was 70%, while in the GW group it was 30% (P < 0.05). Overall, obliteration was achieved in only 32% of the STS group and 81% of the GW group during admission (P < 0.05). There was a trend toward a higher gastric ulcer rate in the STS group compared with the GW group (92% vs. 30%; P < 0.05). The rebleeding control rate and permanent hemostasis rate in the GW group (70%, 54%) were also significantly higher than in the STS group (21%, 12%; P < 0.05; P < 0.05). The hospital mortality for the STS group was 50%, and for the GW group 30%. CONCLUSION: Treatment with hypertonic glucose water in gastric vericeal bleeding was superior to treatment with STS in controlling bleeding and in achieving vericeal obliteration, less rebleeding, and a lower complication rate. The results of this study suggest that hypertonic glucose water is a clinically effective, easily available, and safe sclerosing agent.

Aged↗
PubMed1996

Clinicopathological study of colorectal mucinous carcinoma in Taiwan: a multivariate analysis.

The clinicopathological significance of colorectal mucinous carcinoma is controversial, although some authors feel mucinous carcinoma has a worse prognosis than that of non-mucinous carcinoma. To clarify the significance of this type of carcinoma in Taiwan, a retrospective review of patients with colorectal carcinoma treated at Chang Gung Memorial Hospital between 1984 and 1988 was undertaken. During this period, 53 mucinous carcinomas and 401 non-mucinous carcinomas fulfilling the inclusion criteria were analysed. Mucinous carcinomas were more common in patients 39 years of age or under (P < 0.005). Most mucinous carcinomas were located in the rectum/rectosigmoid, followed by the right colon; however, the right colon had a higher relative incidence (38 vs 8%, respectively; P < 0.005). Mucinous carcinomas presented at a significantly more advanced stage (23 vs 8%, respectively, stage D disease; P < 0.005) and had a markedly lower curative resection rate (68 vs 84%, respectively; P < 0.05). Following curative resection, mucinous carcinomas tended to have an increased incidence of subsequent distant metastasis (27.8 vs 18.8%, respectively; P < 0.005). The overall survival rate of patients with mucinous carcinoma was worse than that of non-mucinous carcinoma (P < 0.005). Multivariate analysis showed that clinically important predictive factors were stage of disease on diagnosis and subsequent distant metastasis. The mucinous histological type itself was not an independent prognostic factor in colorectal cancer.

Adenocarcinoma↗
PubMed1996

[The investigation of the immunomodulatory effect of san-hwang-sei-sin-tang].

San-Hwang-Sei-Sin-Tang is a famous ancient Kampo. In order to investigate the immunomodulatory effect of this Kampo, we can stimulate lymphocytes with PHA to study the lymphocyte transformation and IL-2 production as indicators of effect. In this study, we found that the extract of San-Hwang-Sei-Sin-Tang at the concentration of 0.1 mg/ml and 1 mg/ml could effectively inhibit the index of lymphocyte transformation. San-Hwang-Sei-Sin-Tang at the concentration of 0.01 mg/ml, 0.1 mg/ml and 1 mg/ml also have the tendency of inhibition of IL-2 production. In the future, San-Hwang-Sei-Sin-Tang may be developed as an effective immunosuppressant.

Dose-Response Relationship, Drug↗
PubMed1996

Primary signet ring cell carcinoma of colorectum: an age- and sex-matched controlled study.

OBJECTIVE: To evaluate the differences of clinicopathological features between colorectal signet ring cell carcinoma and ordinary adenocarcinoma. METHODS: The clinicopathological data of 28 cases with primary colorectal signet ring cell carcinoma was reviewed and compared with the data from 56 age- and sex-matched patients with ordinary adenocarcinoma. RESULTS: Fifteen cases (53.5%) with primary signet ring cell carcinoma were younger than 40 yr of age. Compared with 985 ordinary adenocarcinoma cases, signet ring cell carcinoma is present in excess in younger patients (p < 0.005). Further comparison with 56 age- and sex-matched ordinary adenocarcinomas showed that signet ring cell carcinomas could affect any sites of colon, presented as scirrhous appearance more frequently, had a higher percentage of stage III or IV tumors (78.6 vs 48.2%, 14.3 vs 7.2%, p < 0.005), had a higher rate of peritoneal seeding (35.7 vs 12.5%, p < 0.005) but a lower rate of liver metastasis (14.3 vs 32.1%, p < 0.005), and had a lower curative resection rate (64.2 vs 80.4%, p < 0.005) and a higher local or distant metastasis rate (61.1 vs 17.8%, p < 0.05). Survival with signet ring cell carcinoma is lower than that of ordinary adenocarcinoma. "Stage-on-diagnosis" and "presence of subsequent distant metastasis" were the major factors influencing survival of signet ring cell carcinoma patients. CONCLUSION: The delay in diagnosis reduces the chance of curative resection, increases the possibility of local or distant metastasis postoperatively, and, thus, shortens the survival chances. To improve outcome, recognition of the factors responsible for this delay should be stressed so that this tumor may be found at a stage when cure is possible.

Adenocarcinoma↗
PubMed1996

Squamous cell carcinoma of the ampulla of Vater: a case report.

A wide variety of neoplastic lesions may involve the ampulla of Vater, but squamous cell carcinoma has not been reported. Here we report a case of squamous cell carcinoma of papilla Vater. A 72-year-old Chinese female was manifested by obstructive jaundice and biliary tract infection. Duodenoscopic study revealed a polypoid mass with deep and broad ulcer on the ampulla of Vater. Histological examination revealed a metastatic squamous cell carcinoma. The gynecologist had examined the patient carefully and revealed a negative tumor survey. Other sources were also intensively studied but which revealed nothing. The patient developed biliary tree infection after endoscopic retrograde cholangiopancreatic study so that percutaneous transhepatic cholangiography & drainage was performed. Pseudomonas aeruginosa and Enterococcus were cultured from the drainaged bile. Radiotherapy was used and the bleeding was halted temporarily but the patient later expired due to persistent bleeding.

Aged↗
PubMed1996

Clinical challenge--an experience of spontaneous transmural rupture of the oesophagus in Taiwan.

In Taiwan, spontaneous oesophageal rupture is uncommon but the outcome is often lethal because of failure to make an early diagnosis. We have analysed clinical data, management and the risk factors that affect mortality for a consecutive series of 11 patients who had spontaneous oesophageal perforation between 1983 and 1994. The primary symptom was chest or abdominal pain, which was present in 100% of patients; 91% of patients had abnormal chest x-ray (63% pleural effusion, 46% pneumomediastinum, 37% subcutaneous emphysema). In our series of patients the lower thoracic area was the most common location of the perforation (80% of patients. There were no statistically significant differences in mortality due to age, underlying disease, perforation size, location or surgical methods. A poor prognosis seems to be correlated with the time elapsed between the perforation and treatment (especially if > 72 hours) (p < 0.05), respiratory failure (p < 0.05), and heavy contamination of the mediastinum (p < 0.05). The clinical findings depend on the location and time of perforation. History, chest x-ray and oesophagogram are the most useful diagnostic tools. Early diagnosis and treatment are mandatory for these patients.

Adult↗