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Biomedical subjects

W Y Chang

Publications and source records attributed to W Y Chang.

At least 109 records · Page 6Linked to original sources
PubMed1994

Paraumbilical vein tumor thrombosis in hepatocellular carcinoma.

To evaluate the incidence and role of paraumbilical vein tumor thrombosis (PUVT) in hepatocellular carcinoma, we studied 431 patients with hepatocellular carcinoma. Nine patients (2.1%), all male, presented with PUVT. Eight of those patients were positive for hepatitis B surface antigen, with the size of the main tumor being at least 9 cm. All nine patients had a combination of left lobe invasion and left portal vein thrombosis. The dilated paraumbilical vein was not present before the PUVT occurred. The survival time for these nine patients was from 3 to 180 days (median 25 days). The poor prognosis of patients with PUVT resulted from the advanced stage of hepatocellular carcinoma and already poor general physical condition of these patients, but was not a result of the PUVT itself. We present a possible sequence of formation of PUVT.

Adult↗
PubMed1993

Hepatitis C virus infection as a risk factor for non-alcoholic liver cirrhosis in Taiwan.

To assess whether hepatitis C virus infection was a risk factor for the development of non-alcoholic liver cirrhosis, antibody to hepatitis C virus (anti-HCV; detected by a second generation HCV enzyme immunoassay), hepatitis B surface antigen (HBsAg; detected by radioimmunoassay) were tested in 150 cirrhotics and 150 sex-matched and age-matched healthy controls. The prevalence of anti-HCV and HBsAg in cirrhotics was higher than in controls (22.0%, 73.3% vs. 2%, 18.7%; P = 0.001). The prevalence of anti-HCV in HBsAg-negative cirrhotics (45.0%) was higher than that in HBsAg-positive patients (13.6%; P = 0.001). Both the anti-HCV and carriage of HBsAg were associated significantly with liver cirrhosis, showing odds ratio of 12.0 for HBsAg carriers and 13.8 for patients with anti-HCV. Compared with those without HBsAg and anti-HCV, there was a significantly positive linear trend for developing cirrhosis with the presence of HBsAg alone (odds ratio = 19.9), anti-HCV alone (odds ratio = 49.0), and those positive for HBsAg and anti-HCV (odds ratio = 81.8) (P = 0.00001). The population-attributable risk for developing liver cirrhosis was estimated as 10.8% for anti-HCV alone, 55.2% for HBsAg alone, and 9.4% for both anti-HCV and HBsAg in southern Taiwan. In conclusion, this study shows that hepatitis B and C virus infection act independently and synergistically in the development of non-alcoholic liver cirrhosis among Chinese in Taiwan.

Age Factors↗
PubMed1993

The role of hepatitis C virus in chronic hepatitis B virus infection.

To investigate the influence of hepatitis C virus (HCV) infection on patients with chronic hepatitis B virus (HBV), the presence of antibody against C100-3 antigen of HCV (anti-HCV) was examined in 420 patients with chronic HBV infection and 275 healthy subjects. It was found that the prevalence of HCV infection increased in parallel with the severity of liver damage. The positive rates of anti-HCV were as follows: healthy subjects, 2.9% (8/275); asymptomatic carriers, 2.6% (5/193); chronic hepatitis, 5.2% (3/58); liver cirrhosis, 11.4% (8/70); hepatocellular carcinoma (HCC), 12.1% (12/99). To elucidate the interaction of these two viruses in hepatocellular carcinoma, 128 HCC patients and 384 age-matched and sex-matched subjects were further analyzed. Eighty-seven of 128 HCC patients (68.0%) were only positive for HBsAg, 13 patients (10.1%) were only anti-HCV positive, and 12 (9.4%) were positive for both markers. The presence of HBsAg and anti-HCV was associated strongly with HCC. Moreover, the risk of HCC was significantly higher when both HBsAg and anti-HCV were present simultaneously. These results suggested that concurrent HCV infection might accelerate the progression of chronic HBV infection and may contribute to the pathogenesis of HCC in patients with chronic HBV infection.

Carcinoma, Hepatocellular↗
PubMed1993

Precore mutations and core clustering mutations in chronic hepatitis B virus infection.

BACKGROUND: Mutant hepatitis B virus is often associated with severe liver damage. The purpose of this study is to elucidate the relationship between mutations in hepatitis B precore/core gene and the severity of liver damage. METHODS: The hepatitis B precore/core gene from 20 patients with chronic hepatitis B virus infection was studied by polymerase chain reaction and direct sequencing. RESULTS: Missense mutations in the core gene were only found in patients with chronic active hepatitis. Three mutation clustering regions of core gene, codons 48-60, 84-101, and 147-155, had higher substitution rates than other regions. All patients with chronic active hepatitis had missense mutation(s) either in codons 84-101 or in codons 48-60. There was a trend of increasing substitutions in the precore/core gene from e antigen-positive asymptomatic carriers to e antibody-positive patients with chronic active hepatitis. CONCLUSIONS: These data suggest that (1) severe liver damage in chronic hepatitis B virus infection is related to the clustering missense mutations in codons 48-60 and 84-101 of core gene and that (2) the emergence of precore stop codon mutation and missense mutations around the carboxy-terminal processing site of precore/core protein (codons 147-155) may be the adaptive mechanisms of hepatitis B virus to decrease production and secretion of viral protein and retain the viral persistence.

Adult↗
PubMed1993

Transforming growth factor-beta(1) regulates differentiation of porcine granulosa cells in vitro.

Transforming growth factor-beta (TGF-beta) is a potential regulator of ovarian function and follicular development. It is speculated that TGF-beta mediates the events in the follicle which culminate in ovulation of the oocyte. The complex processes which ultimately leads to this natural phenomenon must involve interactions between the 2 major follicular cell types, theca and granulosa cells, and the oocyte. Furthermore, a complex local regulatory system must exist to determine which follicles should undergo development and, eventually, which of those should ovulate or undergo atresia. To begin to understand this perplexing process, we must first understand the variables which control the function of each individual cell type. This study investigated the effect of TGF-beta(1) on FSH-induced porcine granulosa cell differentiation in vitro. Transforming growth factor-beta(1) was shown to inhibit progesterone production at high concentrations (0.1 and 10.0 ng/ml) after 12-, 24- and 48-hour treatment. However, TGF-beta(1) produced a biphasic effect on FSH-induced progesterone production during the 12-hour interval between the 36- and 48- hour treatment periods; TGF-beta(1) stimulated progesterone production at a low concentration (0.001 ng/ml) and inhibited production at high concentrations (0.1 and 10.0 ng/ml). The results obtained from the biphasic effect were not observed during any of the other incubation periods or intervals investigated. These results show that TGF-beta(1) has opposing effects on the differentiation of porcine granulosa cells as compared with those on rat granulosa cells. Moreover, TGF-beta(1) can produce opposing effects within the porcine granulosa cell itself which are specific to the concentration and treatment period used. The results of this study seem to suggest that TGF-beta(1) is species- and time-specific in its regulatory actions on FSH-induced porcine granulosa cell differentiation.

Journal Article↗
PubMed1993

Asbestos related pleural plaques in retired boiler room workers.

Occupational disease is often underestimated and only a few formal reports have been published in Taiwan. This study reports of a group of workers with asbestos-induced-disease, pleural plaque in Taiwan. Pleural plaque is a marker of exposure to asbestos. The disease was found in chest radiographs of five boiler room workers in a sugar refining factory. The chest radiographs of 248 current workers in that plant were reviewed, and none of them was found to have pleural plaques. The storage of asbestos and the long-time use of mixed asbestos cement for insulation of the inner wall of the stove and pipes were found in the factory. The authors believe that the pleural plaques might be resulted from occupational exposure to asbestos. It is suggested that the use of asbestos should be prohibited, step by step, and regular follow-up of the workers with an asbestos exposure history is required.

Aged↗
PubMed1992

The role of hepatitis B and C viruses in hepatocellular carcinoma in a hepatitis B endemic area. A case-control study.

To investigate the role of hepatitis B (HBV) and C viruses (HCV) in hepatocellular carcinoma (HCC) in an HBV endemic area and elucidate the interaction of these two viruses, a case-control study of 128 patients with HCC and 384 age-matched and sex-matched control subjects was done. The positive rates of hepatitis B surface antigen (HBsAg, 77.3%, 99 of 128) and anti-HCV (19.5%, 25 of 128) in patients with HCC were significantly higher than in control subjects (P less than 0.001). Both HBsAg and anti-HCV were important risk factors for HCC (relative risks, 13.96 and 27.12, respectively), and the risk for HCC was elevated significantly to 40.05 (95% confidence interval, 12.57 to 127.6) when HBsAg and anti-HCV were considered simultaneously. These results suggested that HBV and HCV were associated highly with HCC in an HBV endemic area and that these two viruses might contribute independent but synergistic effects to the pathogenesis of HCC.

Adult↗
PubMed1992

Treatment of hepatocellular carcinoma by transcatheter arterial chemoembolization and analysis of prognostic factors.

A total of 100 patients with histologically proven hepatocellular carcinoma (HCC) underwent transcatheter arterial chemoembolization (TACE) and were followed for more than 1 year and 10 months. Portal vein branch thrombosis was diagnosed in 14 patients, and extrahepatic metastasis was noted in 11 subjects. The embolization material used was iodized oil (0.1-0.2 ml/cm tumor area at its maximal diameter), which was prepared by pumping with contrast agent and then mixed with anticancer drugs; Gelfoam particles measuring 1-2 mm in size were subsequently injected. The overall cumulative 0.5- 1-, 2-, and 3-year survival rates were 81%, 57%, 31%, and 21%, respectively. Patients with an intact capsule and those with solitary lesions, especially when the tumor diameter was < 5 cm, achieved a higher survival rate. In contrast, incomplete TACE, extrahepatic metastasis, and portal vein thrombosis were associated with the worst outcome. Patients with positive HBsAG and diffuse or multiple tumors also showed a poor outcome. Early diagnosis and early treatment of HCC are the keys for the achievement of better clinical results.

Adult↗
PubMed1992

Radiotherapy in the treatment of hepatocellular carcinoma and its metastases.

A study was conducted to evaluate the effect of external radiation therapy on hepatocellular carcinoma (HCC) and its metastatic lesions. A total of 33 patients with cytopathologically proven HCC were subjected to radiation therapy over a 4-year period, and treatment was discontinued in 8 cases due to jaundice, severe discomfort, or early mortality. Thus, 25 patients with 28 lesions underwent irradiation with a total dose ranging between 3000 and 5600. Of these, seven were irradiated for liver tumors, and the results showed that two lesions decreased in size, the symptoms improved in 1 case, and another patient maintained stable disease for 4 months. Among the 21 metastatic lesions treated, only 2 patients failed respond to the treatment. Nine subjects were irradiated for bone metastases, and the bone pain subsided in all but one case. The survival for bone metastasis was as long as 23 months when the primary tumor was treated effectively. Three of the four cases of irradiated skin nodules disappeared and had not recurred after 5 months, 1 year, and 4 years, respectively. Tumor shrinkage or symptoms of relief were noted for three abdominal lymph nodes, one neck lymph node, one pleural tumor, and one lung tumor. Clinical improvement associated with a stable lesion was observed in two patients with brain metastasis. Follow-up revealed regrowth of the tumor or recurrence of symptoms in most of the patients. However, none of the patients died as a direct result of a metastatic lesion. Although external radiation therapy is palliative in intent, it appears to be useful in the treatment of HCC and its metastatic lesions.

Adult↗
PubMed1992

Duplex pulsed Doppler sonography in the differential diagnosis of hepatocellular carcinoma and other common hepatic tumours.

180 previously untreated consecutive patients with liver tumours (308 lesions), including 104 hepatocellular carcinomas (148 lesions), 43 metastases (116 lesions) and 33 haemangiomas (44 lesions), were studied to determine the value of duplex sonography in the differentiation of hepatocellular carcinoma from other tumours. For lesions measuring less than or equal to 5 cm in diameter, hepatocellular carcinoma demonstrated the highest rate and haemangioma demonstrated the lowest rate of Doppler signals from within the lesions. To differentiate malignancy from haemangioma, the presence or absence of Doppler signals from these lesions were used as criteria. The specificity and positive predictive value were very high (100%, 100%), but the sensitivity, negative predictive value and accuracy were low (61.5%, 48.3%, 71.7%, respectively). With one exception, all lesions measuring less than 3 cm in diameter with detectable Doppler signals were hepatocellular carcinoma. Using these results it is possible to differentiate hepatocellular carcinoma from metastases and haemangioma with high sensitivity, specificity, positive and negative predictive value, and accuracy (80.8%, 96.4%, 95.5%, 84.4%, 88.9%, respectively, for metastases; 80.8%, 100%. 100%, 81.5%, 89.6%, respectively, for haemangioma). We conclude that Doppler signals from within a lesion in combination with its size can aid differentiation of hepatocellular carcinoma from two other kinds of common hepatic tumour.

Adult↗
PubMed1992

Clinical utility of pulsed Doppler in the detection of arterioportal shunting in patients with hepatocellular carcinoma.

Ninety-seven patients with hepatocellular carcinoma had duplex scanning from the patent or residual portal lumen and comparative angiography. Duplex ultrasonography identified five of nine patients with angiographic evidence of arterioportal shunting. Furthermore, Doppler results indicated the presence of the shunt in one patient without angiographic evidence. Duplex scanning from the portal lumen may be useful in the detection of arterioportal shunting. This procedure can be used to evaluate the hemodynamic change of the recipient portal vein under natural physiologic conditions. However, small shunts without hepatofugal portal blood cannot be detected by this procedure.

Adult↗
PubMed1991

Natural killer cell activity in patients with liver cirrhosis relative to severity of liver damage.

To evaluate the role of severe liver damage on natural killer cell activity, 29 patients with liver cirrhosis were examined. The natural killer cell activity was measured with a 4-hr chromium release assay, and the K562 cell line was employed as target cells. The natural killer cell activity was significantly decreased in cirrhotic patients compared with normal controls and patients with chronic active hepatitis. Cirrhotic patients with Pugh's C grade of severity of liver disease had lower natural killer cell activity. The depression of natural killer cell activity in cirrhotic patients was inversely correlated with prothrombin time ratios, and the natural killer cell activity in cirrhotic patients with hepatic encephalopathy was lower than in patients without hepatic encephalopathy. Thus, the diminished natural killer cell activity in cirrhotic patients might be related to the severity of liver damage.

Female↗
PubMed1991

Systemic amyloidosis presenting as splenic tumor.

We report a case of amyloidosis manifesting as a splenic tumor and pleural effusion. Only one case of a splenic amyloid tumor has been reported in the literature, but its radiological findings were not described. Therefore, we present the computed tomographic (CT), sonographic, and angiographic features of splenic amyloid tumor.

Amyloidosis↗
PubMed1991

Elevation of circulating immune complexes and its relationship to alpha-fetoprotein levels in patients with hepatitis B surface antigen-positive hepatocellular carcinoma.

In an attempt to evaluate the relationship between circulating immune complexes (CIC) and alpha-fetoprotein (AFP), CIC and AFP were detected in 93 hepatitis B surface antigen-positive (HBsAg+) patients with hepatocellular carcinoma (HCC) and 54 healthy controls. The median level of 3% PEG (polyethylene glycol)-CIC and Clq-CIC were higher in patients than in controls (p less than 0.001). In patients with HCC, the prevalence of elevated 3% PEG-CIC, Clq-CIC, and AFT was 27.9%, 55.9%, and 77.4%, respectively. There was association between AFP and 3% PEG-CIC positivity (p less than 0.01). The median level of 3% PEG-CIC and Clq-CIC increased as AFP levels elevated (p less than 0.05), but decreased as AFP exceeded 1599 ng/ml (p less than 0.05). For adjusting the effect of impaired liver function on the level of CIC, multivariate analysis with stepwise logistic regression revealed that 3% PEG-CIC was associated, in a dose-related fashion, with an increased risk for developing HCC (odds ratio = 1.003, p less than 0.001). These results imply that elevation of 3% PEG-CIC may be related to tumor mass. Additionally, 3% PEG-CIC is a useful marker to monitor therapy with transcatheter arterial embolization in patients with HBsAg+ HCC.

Adult↗
PubMed1991

Duplex pulsed Doppler sonography of hepatocellular carcinoma treated with transcatheter arterial embolization.

Thirty-one patients with hepatocellular carcinoma underwent duplex scanning of their lesions with comparative angiography and serum alpha-fetoprotein determinations before and after transcatheter arterial embolization. Duplex ultrasound correctly identified 26 patients with patent tumor vessels after embolization. The Doppler signals became undetectable after embolization in the other five patients. Comparative angiography demonstrated good devascularization of their lesions. However, tiny tumor blush or small satellite nodules around the periphery of the devascularized masses were found. Therefore, the presence of signals after therapy indubitably needs further embolization. The timing of the second embolization for the patient with undetectable Doppler signals after the first embolization needs to be justified by further evaluations.

Adult↗
PubMed1991

Duplex pulsed Doppler sonography of portal vein thrombosis in hepatocellular carcinoma.

Sixteen patients with hepatocellular carcinoma had duplex pulsed Doppler scanning of the portal thrombus and comparative angiography. Fifteen patients demonstrated detectable Doppler signals from the thrombus. The Doppler signals were corroborated by the "thread-and-streaks" sign on angiography in eight patients. This suggests that signals come from tumor vessels within the thrombus. Therefore, the presence of Doppler signals in the thrombotic portal venous system is not only due to partial obstruction of the lumen. Tumor thrombus from hepatocellular carcinoma must be considered, especially when the detectable signals are pulsatile waves.

Adult↗
PubMed1991

Transrectal ultrasound of the prostate: the early Singapore experience.

During a four-month-period 40 patients presenting to the Department of Urology with mainly retention of urine had their prostates scanned ultrasonically. Eight nodules were detected on the ultrasound of which five were not detected on digital rectal examination. Of the five non-palpable nodules two were diagnosed on ultrasound guided transperineal Tru-cut biopsy to be carcinomas. Of the three nodules detected both on ultrasound and digital rectal examination, two were proven to be carcinomas while the other was benign. The transrectal ultrasound was not only found to be easy to use but was also found to be a useful complement to the urologist's index finger with the added advantage of obtaining good quality biopsy material from suspicious lesions.

Aged↗