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Biomedical subjects

Z Y Lin

Publications and source records attributed to Z Y Lin.

At least 91 records · Page 5Linked to original sources
PubMed1994

Effects of hepatitis C and B viruses infection on the development of hepatocellular carcinoma.

A case control study consisting of 102 patients with HCC, 102 sex-matched and age-matched patients with nonhepatic disease, and 204 matched healthy controls was carried out to investigate the effect of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection on the development of hepatocellular carcinoma (HCC). The prevalence of antibody to HCV (anti-HCV) in HCC (34.3%) was higher than in nonhepatic disease (10.7%, P < 0.001) or in healthy controls (2.4%, P < 0.001). The prevalence of hepatitis B surface antigen (HBsAg) in HCC (77.4%) was higher than in nonhepatic disease (16.6%, P < 0.001) or in healthy controls (19.6%, P < 0.001). Anti-HCV positivity in nonhepatic disease was higher than in healthy controls (P < 0.01). Using patients with nonhepatic disease as controls, stepwise logistic regression analysis indicated that both anti-HCV (odds ratio, 3.4; 95% confidence interval, 2.1-5.6) and HBsAg (odds ratio, 5.6; 95% confidence interval, 3.6-8.5) are independent risk factors for HCC. Using healthy controls, the development of HCC was also strongly associated with anti-HCV (odds ratio, 8.0; 95% confidence interval, 4.3-14.6) and HBsAg (odds ratio, 5.5; 95% confidence interval, 3.7-8.2). Calculation of incremental odds ratio indicated that there is no interaction between HBV and HCV. In conclusion, HBV and HCV are risk factors of HCC. They act independently and without interaction.

Adult↗
PubMed1994

Recurrence after resection of alpha-fetoprotein-positive hepatocellular carcinoma.

The long-term prognosis of surgery for hepatocellular carcinoma (HCC) is not yet satisfactory, the main reason being the high recurrence rate. The authors report the results of a long-term follow-up of 308 patients with HCC who became alpha-fetoprotein-(AFP)-negative after resection between 1975 and 1991. By March 1992, there was recurrence in 134 patients (43.5%). The 1-, 3-, 5- and 10-year recurrence rates were 9.2%, 38.8%, 54.9% and 85.0%, respectively. The 5-year survival rate was 49.7% for patients who had undergone a second hepatic resection (n = 48). Analysis of factors influencing postoperative recurrence indicated that patients subjected to mass survey, with a lower gamma-glutamyltransferase level, at an early stage of TNM classification, with a tumour of less than 5 cm, without tumour embolus, and with postoperative immunotherapy had a lower incidence of recurrence. It is concluded that the earlier the disease is diagnosed, the less the recurrence rate; adjuvant immunotherapy may reduce postoperative recurrence, and the early detection and resection of a recurrent tumour are important to prolonging survival further after curative resection of HCC.

Adult↗
PubMed1994

Recursive running DCT algorithm and its application in adaptive filtering of surface electrical recording of small intestine.

A rhythmic electrical signal is present in the human small intestine and can be recorded using surface electrodes. Surface electrical recordings of the small intestine contain severe interference that obscures the electrical signal of the small intestine. An adaptive system is proposed in the paper for the enhancement of the small-intestinal signal. To obtain better performance, adaptive signal enhancement is performed in the transform domain using a discrete cosine transform (DCT). A fast recursive algorithm is developed for the calculation of running DCT. The computational complexity of the proposed recursive algorithm is only 2/N (N = length of the adaptive filter) of the direct calculation of the running DCT. A series of simulations are conducted to investigate the performance of the proposed transform-domain adaptive filtering using DCT in comparison with time-domain adaptive filtering and with transform-domain adaptive filtering using a discrete Fourier transform (DFT). The parameters of the proposed adaptive system are optimised, and their effects on system performance are investigated. The application of the proposed method for the enhancement of the small-intestinal signal is presented and discussed.

Algorithms↗
PubMed1994

Time-frequency representation of the electrogastrogram--application of the exponential distribution.

The aim of this paper was to examine the applicability of the exponential distribution for the time-frequency representation of the electrogastrogram (EGG). The EGG is a noninvasive measurement of the electrical activity of the stomach by placing electrodes on the abdominal skin. Quantitative analysis of the EGG has relied on spectral methods. The normal frequency of the EGG in humans is 3 cycles/min. Electrical dysrhythmia observed in the EGG is associated with motor disorders of the stomach. The exponential distribution was applied in this work for the estimation of EGG frequency and the detection of dysrhythmia in the EGG. A series of computer simulations was conducted, demonstrating the reliability of the exponential distribution in the analysis of nonstationary electrical signals of the stomach. Applications of the exponential distribution in the spectral analysis of typical EGG's were presented. The results showed that there is a great potential for the use of the exponential distribution in EGG analysis.

Computer Simulation↗
PubMed1994

Hepatitis B and C virus infection as risk factors for liver cirrhosis and cirrhotic hepatocellular carcinoma: a case-control study.

To investigate whether hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are risk factors for liver cirrhosis and hepatocellular carcinoma (HCC), a case-control study of 102 cirrhotic HCC patients, 102 sex-matched and age-matched patients with liver cirrhosis, and 102 matched patients with non-hepatic disease controls was performed. The prevalences of hepatitis B surface antigen (HBsAg) and antibody to HCV (anti-HCV) in HCC (70.5%, 39.2%) and liver cirrhosis (74.5%, 27.4%) were higher than controls (16.6%, 10.5%) (P = 0.0001). In HBsAg-negative patients, the prevalence of anti-HCV in cirrhotic HCC (66.6%) and liver cirrhosis (46.1%) was higher than in controls (10.5%; P = 0.0001). There was no such difference in HBsAg-positive patients. Multivariate analysis revealed that both HBsAg and anti-HCV were important risk factors for HCC (odds ratio, 6.52 and 4.59, respectively) and liver cirrhosis (odds ratio, 4.22 and 2.29, respectively). There was no difference in odds ratio when HCC and liver cirrhosis were compared. Our result implies that both HBV and HCV are independent risk factors for cirrhotic HCC and liver cirrhosis in Taiwan.

Carcinoma, Hepatocellular↗
PubMed1994

Hepatitis C virus infection among patients with chronic liver disease in an area hyperendemic for hepatitis B.

BACKGROUND: The prevalence of hepatitis C virus (HCV) infection was assessed in patients with non-alcoholic chronic liver disease (CLD). METHODS: Antibody levels to HCV (anti-HCV) were assessed in 100 pairs of CLD patients and healthy controls. RESULTS: The prevalence of anti-HCV was higher in patients (26.0%) than in controls (2.0%; p = 0.0001). The patient group with anti-HCV was older (p = 0.0001) and had more smokers (p = 0.034), fewer hepatitis B surface antigen carriers (p = 0.0001), and more patients with active liver disease (p = 0.023) and a history of blood transfusion (p = 0.026). Multivariate analysis showed that anti-HCV (odds ratio, 8.1; 95% confidence intervals, 3.7-17.6) was strongly associated with CLD. CONCLUSIONS: HCV infection is a risk factor of non-alcoholic CLD, and HCV causes more severe hepatocellular damage than HBV.

Adult↗
PubMed1994

Antibodies to hepatitis E and A viruses among patients with non-alcoholic chronic liver disease in Taiwan.

BACKGROUND: The prevalence of hepatitis E virus (HEV) and hepatitis A virus (HAV) infection in patients with non-alcoholic chronic liver disease (CLD) was assessed. METHODS: Antibody levels to HEV (anti-HEV) and HAV (anti-HAV) were evaluated in 100 pairs of CLD patients and healthy controls. RESULTS: The prevalence of anti-HEV was higher in patients (10.0%) than in controls (0%; p = 0.0001). There was no difference in anti-HAV positivity between patients (95%) and controls (93%). The patient group with anti-HEV was older (p = 0.024) and had more smokers (p = 0.03), having a higher prevalence of antibodies to hepatitis C virus (p = 0.02). Patients with anti-HAV were older than patients without (p = 0.0001). The prevalence of anti-HAV in patients more than 30 years old was higher than younger patients (95.1% versus 73.6%, p = 0.011). CONCLUSION: HEV may superinfect on chronic liver disease in an area hyperendemic for hepatitis A and B.

Adult↗
PubMed1994

Biochemical and biophysical properties of recombinant human interphotoreceptor retinoid binding protein.

PURPOSE: Interphotoreceptor retinoid-binding protein (IRBP) binds and transports retinoids and fatty acids in the interphotoreceptor space (IPS). To understand the relationship between the protein structure and its functions requires bulk quantities of human IRBP. The authors sought to produce recombinant human IRBP (rhIRBP), a perfect duplicate in amino acid sequence of the authentic human protein. This material could serve as a supply of the protein and later could be used to make mutants of the protein. The goals of the present study were to produce human IRBP in an expression system and to examine some of its biochemical properties. METHODS: A cDNA encoding human IRBP was cloned into the transplacement vector, pVL1392, and the plasmid was recombined with linearized baculovirus on cotransfection into Sf9 cells. Viruses containing the human IRBP cDNA were identified by polymerase chain reaction analysis. IRBP was secreted from virus-infected insect cells. rhIRBP was purified from cell medium and was examined by chromatography, N-terminal protein sequencing, immunologic techniques, and fluorometry. Eyecup and retina washes of human donor eyes provided a source of authentic human IRBP (IPS-IRBP). RESULTS: rhIRBP and IPS-IRBP exhibit similar elution profiles on concanavalin A, ion-exchange, and size exclusion chromatography. rhIRBP contains a five-amino-acid propeptide at the N-terminus as deduced from the cDNA sequence. Retinol binding of rhIRBP has been characterized by fluorometric titration. The dissociation constant is approximately 1.04 microM, close to that reported for bovine IRBP. By scanning fluorometry, the emission and excitation maxima are 479 nm and 339 nm, respectively. CONCLUSIONS: The baculovirus system provides an excellent method to produce and secrete human IRBP. The recombinant protein can be readily purified from cell culture medium. Its behavior in chromatography and in binding studies suggests that the recombinant protein is virtually identical to the authentic protein. This validates its use in place of IRBP from human donor eyes. Small, but significant, differences in biochemical properties in comparing human and bovine material highlight the significance of studying the human protein.

Amino Acid Sequence↗
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

Subclinical hepatocellular carcinoma: an analysis of 391 patients.

Subclinical hepatocellular carcinoma (SCHCC) is defined as HCC without obvious HCC symptoms and signs. During 1958-1991, 391 patients with SCHCC were analyzed. In the entire series, 1) 67.3% was detected by natural population screening using alpha-fetoprotein (AFP) serosurvey, while the others were discovered by high-risk population screening or regular health checkup using AFP and/or ultrasonography (US); 2) AFP > 20 micrograms/L was found in 77.6% of patients; 3) serum hepatitis B surface antigen (HBsAg) was positive in 68.9%; 4) associated liver cirrhosis occurred in 89.1%; 5) the median tumor size was 5 cm, and small HCC (< or = 5 cm) amounted to 61.1%; 6) resection was done in 81.4%, and limited resection was performed in the majority (71.3%); 7) re-resection for subclinical recurrence was done in 44 patients; and 8) cytoreduction and sequential resection was carried out in 13 patients with unresectable SCHCC. Comparison between SCHCC and clinical HCC (n = 1,251) revealed higher resectability (81.4% vs. 46.8%), lower operative mortality (1.9% vs. 6.0%), and higher 5-year survival (entire series: 50.7% vs. 20.6%; resection: 60.5% vs. 36.8%). It is concluded that the study of SCHCC has resulted in marked improvement of ultimate outcome of HCC; screening in high-risk populations using AFP and/or US, limited resection, and re-resection for subclinical recurrence are some of the key features.

Adult↗
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

[Synthesis of gona-3,5-dienes and studies on their activity for interruption of early pregnancy].

A series of gona-3,5-dienes were synthesized from norgestrel, norethisterone 17 alpha-hydroxyprogesterone and ethisterone via reduction of alpha, beta-unsaturated 3-ketones to allylic alcohols and dehydration with concomitant migration of the double bond. The structures of these gona-3,5-dienes were verified by MS and 1H-NMR spectral data. Pharmacological results showed that compound IVb2 in this series gave rise to significant interruption of early pregnancy in mice. The mechanism of the early pregnancy terminating effect of this compound was discussed.

Abortifacient Agents, Steroidal↗
PubMed1993

Surgical treatment of recurrent hepatocellular carcinoma.

During the last 16 years, radical resection was performed in 392 patients with hepatocellular carcinoma (HCC). Eight patients died within 30 days after resection. The other 384 patients were discharged from hospital and closely followed for 6 to 195 months. By December 1991, 185 patients had developed a recurrent tumor, the 1-, 3-, and 5-year recurrence rates being 15.0%, 45.4%, and 55.3%, respectively. Ninety of the 185 patients underwent reoperation, including second hepatic resection (65 cases), cryosurgery (8 cases), resection of lung metastasis (6 cases), hepatic artery ligation and infusion chemotherapy (2 cases), intratumor ethanol injection (3 cases), microwave coagulation plus intratumor ethanol injection (2 cases), and exploration (4 cases). The survival rate of these 90 patients was significantly better than that of 95 patients who were treated by other palliative methods, the 5-year survival rate being 63.4% as compared with 28.6% after the first resection (P < 0.01), and 40.8% vs. 2.2% after recurrence (P < 0.01), respectively. These results suggest that reoperation for recurrent HCC might be an important approach to prolonging survival further after hepatic resection.

Adult↗
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

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

Solitary minute hepatocellular carcinoma. A study of 14 patients.

Fourteen patients with clinical Stage I hepatocellular carcinoma (T1N0M0) were studied. All patients were asymptomatic, and their conditions were detected by alpha-fetoprotein (AFP) serosurvey and/or ultrasonography (US) either in the natural population in the early years of the study or in the high-risk population in the later years of the study. Cirrhosis was present in all patients. Radical resection was performed in all patients. There were no operative deaths or hospital deaths in this series. The 5-year survival rate after resection was 100%. There were seven long-term survivors in this series (14.2 years (alive), 11.3 years (alive), 8.8 years (alive), 8.8 years, 7.9 years, 7.6 years (alive), and 7.2 years after resection). The authors discuss aspects concerning early diagnosis, treatment, and prognosis of hepatocellular carcinoma (HCC).

Adult↗