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Po-Huang Lee

Publications and source records attributed to Po-Huang Lee.

84 records · Page 5Linked to original sources
PubMed2002

Efficacy of low-dose mycophenolate mofetil therapy for Taiwanese renal transplantation patients receiving primary cyclosporine immunosuppression.

BACKGROUND AND PURPOSE: Mycophenolate mofetil (MMF) in combination with cyclosporine or tacrolimus prevents acute rejection and chronic allograft failure in renal transplantation in Western countries. We began to add low-dose MMF to primary cyclosporine immunosuppressive therapy in renal transplantation at the Department of Surgery of National Taiwan University Hospital in 1998. This study compared low-dose MMF to conventional therapy in Taiwanese renal transplant recipients. METHODS: This retrospective cohort study determined the efficacy of low-dose MMF therapy (1 g/day in divided doses). A total of 275 cases with allograft kidney transplants were grouped according to whether they received transplants before or after the adoption of MMF therapy (Period I: 1987-1993; Period II: 1994-1997; Period III: 1998-September 2000). The prognostic significance of MMF therapy and graft and patient survival rate in each time period were assessed. RESULTS: The 18-month graft survival rate was 84.9% in Period I, 86.3% in Period II, and 91.9% in Period III. The 5-year graft survival rates in Periods I and II were 69.3% and 76.6%, respectively. Acute rejection was significantly detrimental to graft survival (p = 0.048), while MMF therapy was significantly advantageous to graft survival (p = 0.015); treatment when MMF was available was also significantly associated with better graft survival (p = 0.043). There was a negative correlation between acute rejection and graft survival (p = 0.035); MMF therapy produced a protective effect on graft survival independent of acute rejection (p = 0.010). CONCLUSION: Low-dose MMF therapy significantly improved graft survival after renal transplantation in Taiwanese kidney allograft recipients.

Acute Disease↗
PubMed2001

De novo demonstration and co-localization of free-radical production and apoptosis formation in rat kidney subjected to ischemia/reperfusion.

Ischemia-induced oxidative damage to the reperfused kidney was examined. A modified chemiluminescence method, an in situ nitro blue tetrazolium perfusion technique, and a DNA fragmentation/apoptosis-related protein assay were adapted for demonstration de novo and co-localization of reactive oxygen species (ROS) production and apoptosis formation in rat kidneys subjected to ischemia/reperfusion injury. The results showed that prolonged ischemia potentiated proapoptotic mechanisms, including increases in the Bax/Bcl-2 ratio, CPP32 expression, and poly-(ADP-ribose)-polymerase fragments, and subsequently resulted in severe apoptosis, including increases in DNA fragmentation and apoptotic cell number in renal proximal tubules (PT) and distal tubules (DT) in a time-dependent manner. The increased level of ROS detected on the renal surface was correlated with that in blood and was intensified by a prolonged interval of ischemia. The main source of ROS synthesis was the PT epithelial cells. The ROS and apoptotic nuclei detected in the PT cells can be ameliorated by superoxide dismutase (SOD) treatment before reperfusion. However, the apoptotic nuclei remained in DT in the SOD-treated rats, indicating that formation of apoptosis in DT was not influenced by the small amounts of ROS produced. In PT and DT cell cultures, significant increases in apoptotic cells and ROS were evident in PT cells after hypoxia/reoxygenation insult. Furthermore, the oxidative damage in PT, but not in DT, can be alleviated by ROS scavengers SOD and hexa(sulfobutyl)fullerene, confirming that PT are vulnerable to ROS. These results lead us to conclude that ROS produced in significant amounts in PT epithelium under ischemia/reperfusion or hypoxia/reoxygenation conditions may be responsible for the apoptotic death of these cells.

Animals↗
PubMedDate not supplied

Intravasation-related metastatic factors in colorectal cancer.

Alterations in adhesion molecules, angiogenesis, and matrix metalloproteinases have been associated with metastasis and intravasation. The present study investigated the role of these metastatic factors in the context of primary colorectal tumor. Intravasated colorectal epithelial cells were detected by an RT-PCR assay, and the expression of E-cadherin, alpha-catenin, or beta-catenin as well as the vascularity of tumor were assessed by immunohistochemical staining. Activity of matrix metalloproteinase was assessed by gelatin zymography. The tumor venous blood was positive for guanylyl cyclase C (GCC) mRNA expression in 40 of 68 patients, but alteration in expression of E-cadherin, alpha-catenin, or beta-catenin was not significantly associated with the presence of colorectal epithelial cells in paired portal venous blood. Further, matrix metalloproteinase activity did not correlate with the presence of intravasated colorectal epithelial cells. Multivariate analysis demonstrated that the only factor associated with intravasated colorectal tumor cells was the vascularity of the tumor. Thus, metastasis of colon cancer may result from passive entry into the circulation secondary to angiogenic factors and does not appear to involve other metastatic factors studied in our experiments.

Adult↗
PubMedDate not supplied

Effects of a high-fiber diet on hepatocyte apoptosis and liver regeneration after partial hepatectomy in rats with fatty liver.

BACKGROUND: The morbidity and mortality that accompany fatty liver may occur as a result of increased apoptosis of hepatocytes and decreased liver regeneration. We determined the effects of a high-fiber diet on hepatocyte apoptosis and liver regeneration after partial hepatectomy in rats with fatty liver. METHODS: Fatty liver was induced in male Wistar rats weighing around 200 g through feeding of a high-fat diet for 4 weeks. The rats were then randomly assigned to 3 groups that received a high-fat diet, a normal diet, or a high-fiber diet for another 4 weeks. Partial hepatectomy (around 70%) was performed, and rats were killed 6, 24, 48, or 72 hours after hepatectomy. We then measured (1) the ratio of remnant liver weight to body weight and assessed the histology of the remnant liver as indicators of fatty liver, (2) caspase-3 activity and in situ cell death detection of DNA fragmentation as indicators of apoptosis, and (3) 5-bromo-2-deoxyuridine (BrdU) activity and (4) ornithine decarboxylase (ODC) contents in remnant livers as markers of regeneration. RESULTS: We found that (1) a high-fat diet for 4 weeks can markedly induce fatty liver, (2) apoptosis of hepatocytes is greater in fatty liver than in normal liver (98 +/- 19 vs 36 +/- 7) at 6 hours after partial hepatectomy (p < .05), (3) the capacity of liver regeneration decreases significantly (BrdU index: 30 +/- 5 vs 12 +/- 3, and ODC contents: 604 +/- 48 vs 390 +/- 42 mg/dL) in fatty liver 24 hours after partial hepatectomy (p < .05), (4) a normal diet can partially reverse the effects of fatty liver; (5) a high-fiber diet can significantly reverse the effects of fatty liver (p < .05). CONCLUSIONS: A high-fiber diet can reverse the negative effects of fatty liver on apoptosis and regenerative capacity after partial hepatectomy.

Animals↗
PubMedDate not supplied

Reappraisal of the new UICC staging system for gastric cancer: problem in lymph node stage.

BACKGROUND/AIMS: The International Union Against Cancer (UICC) TNM staging system defined a new system for classifying gastric cancer, based on the number of metastatic nodes (1997). However, the advantage of the new system is still a matter of debate. The aim of the present study is to compare the new system with the old one (1987), which is based on the location of positive lymph nodes. METHODOLOGY: We analyzed the survival of 608 patients with curative resection of their gastric cancer. The average number of resected and involved lymph nodes for each resected patient was 31.4 and 7.7. Comparison of these two systems was carried out to determine which classification was more effective. The prognostic value of different lymph node staging systems was also analyzed. RESULTS: One hundred and thirty-five patients (22.2%) had different N classification and 109 (17.9%) had different TNM staging. There was a significant stepwise decrease of slope of survival curve for each stage, but the new system did not cleanly separate stage II with IIIa at 3 years and stage IIIb with IV at 5 years. Although different lymph node staging systems were able to predict survival, the ratio rather than the number of involved nodes had a more cleanly separated stepwise decrease of slope of survival curve. CONCLUSIONS: The new UICC staging system is not better than the old system for the staging of gastric cancer. The reason is that the category of node number seems not to be appropriate and will be influenced by the extent of lymph node dissection. To overcome this problem, the frequency of involved nodes can be adopted instead of the number.

Adenocarcinoma↗
PubMedDate not supplied

Living-related liver transplantation for methylmalonic acidemia: report of one case.

Methylmalonic acidemia (MMA) is an autosomal recessive disease of branched chain amino acid metabolism. The disease can be classified as vitamin B12-responsive or nonresponsive type. For the nonresponsive type, there is no curative treatment, and its prognosis is usually poor. We report one case that had vitamin B12-nonresponsive type MMA diagnosed at 3 days of age. The patient received liver transplantation at the age of 11 months. Continuous venovenous hemodialysis was performed immediately pre- and post-transplantation. The attack frequency of metabolic acidosis episodes decreased and the general condition of this patient improved after liver transplantation. So, although not curative, liver transplantation is an effective management for MMA.

Amino Acid Metabolism, Inborn Errors↗
PubMedDate not supplied

Microbiology difference between colonized catheters and catheter-related bloodstream infections.

BACKGROUND/AIMS: Central vein catheters for patients receiving total parenteral nutrition have a high incidence of colonized catheters and catheter-related bloodstream infections. However, the actual incidence and bacterial pattern have not been well studied. This study was undertaken to investigate the difference in bacteriology between colonized catheters and catheter-related bloodstream infections. METHODOLOGY: From January 1997 to March 1998, 354 patients receiving total parenteral nutrition were included in this study. The patients ranged in age from 49 to 80 years, 151 women and 203 men. Colonized catheters and catheter-related bloodstream infections were defined. RESULTS: The culture was performed in 249 catheter tips (249 of 614, 40.6%). Sixty tips were found to have organisms. The organisms cultured from colonized catheters were Gram(+) aerobic bacteria (34, 56.7%), fungi (14, 23.3%), and Gram(-) aerobic bacteria (12, 20%). The organisms cultured from catheter-related bloodstream infections were fungi (16, 64%), Gram(-) aerobic bacteria (5, 20%), and Gram(+) aerobic bacteria (4, 16%). Dermatogenic infection in colonized catheters should be stressed, but systemic fungal infection in catheter-related bloodstream infections should be emphasized. CONCLUSIONS: A striking difference exists in bacterial species between colonized catheters and catheter-related bloodstream infections. Further studies on different treatment strategy for colonized catheters and catheter-related bloodstream infections should be undertaken. The combined approach of a total parenteral nutrition team, sterile protocols, and early diagnosis of fungemia should be advocated for the total parenteral nutrition patients.

Aged↗
PubMedDate not supplied

Profile of hepatocyte growth factor in patients with obstructive jaundice.

BACKGROUND/AIMS: Hepatocyte growth factor is a potent growth-stimulating factor of many kinds of tissue. Hepatocyte growth factor was demonstrated in the blood of various liver diseases, and its concentration was reported to correlate with liver function after partial hepatectomy. In this study, we monitor the dynamics of bile hepatocyte growth factor in patients with obstructive jaundice. METHODOLOGY: In a university hospital, 68 paired blood and bile samples from 42 patients with hyperbilirubinemia were determined with ELISA. The hepatocyte growth factor bile/blood ratio and both daily hepatocyte growth factor clearance and output were calculated for each pair. The correlations between these values with other biochemical parameters were then determined. RESULTS: The blood hepatocyte growth factor concentration correlated positively with serum bilirubin (r = 0.556, p < 0.001) level, whereas bile hepatocyte growth factor concentration, hepatocyte growth factor bile/blood ratio, hepatocyte growth factor clearance and daily hepatocyte growth factor output correlated negatively with serum bilirubin level (p = 0.006, < 0.001, < 0.001 and 0.002, respectively). Similar strong positive correlations also were found to exist between these hepatocyte growth factor measurements and other liver function parameters. CONCLUSIONS: In this study we demonstrated that the hepatocyte growth factor was significantly higher in bile than in blood and that the excretion of hepatocyte growth factor in the bile was decreased in patients with obstructive jaundice. The higher blood hepatocyte growth factor level in patients with obstructive jaundice might be due to decreased hepatocyte growth factor excretion. The higher hepatocyte growth factor level in bile also might explain why liver cirrhosis occurs after prolonged jaundice.

Bile↗
PubMedDate not supplied

Prognostic factors for hepatocellular carcinoma < or = 3 cm in diameter.

BACKGROUND/AIMS: As surgical morbidity and mortality for hepatocellular carcinoma resection decline, we would like to analyze the possible prognostic factors for small hepatocellular carcinoma after curative resection. METHODOLOGY: A total of 170 patients receiving primary hepatectomies for small hepatocellular carcinoma (< or = 3 cm in diameter) at the National Taiwan University Hospital from December 1987 to February 1997 were enrolled as Group 1. The other 281 patients receiving hepatectomies for hepatocellular carcinoma larger than 3 cm were enrolled as the control group (Group 2). The overall patient and disease-free survival rates were calculated and the possible prognostic factors analyzed. RESULTS: The 1-, 3-, 5-, and 10-year patient survival rates in Group 1 were 89.6, 73.1, 55.7 and 34.0%, respectively. A safety margin > or = 1 cm (p = 0.0283), single tumor (p = 0.0324), and multiple hepatic resection (p = 0.0239) were factors favorable to patient survival by multivariate risk factor analysis. The disease-free survivals for Group 1 were 75.6, 41.4, 25.9 and 19.2% at 1, 3, 5, and 10 years, respectively. Significant factor for better disease-free survival included only euploid DNA content (p = 0.0026). The patient survival and disease-free survival rates of Group 1 were significantly better than those of Group 2. CONCLUSIONS: We conclude that patients with small hepatocellular carcinoma have better prognosis than those patients with larger tumors. Early detection of hepatocellular carcinoma and its recurrence are crucial for both patient and disease-free survival. The only prognostic factors that can be manipulated are the keeping of adequate safety margin and repeated resection for recurrent hepatocellular carcinoma.

Adult↗
PubMedDate not supplied

A child with primary sclerosing cholangitis successfully treated by liver transplantation.

Primary sclerosing cholangitis (PSC) happens mainly in middle-aged men and is seldom diagnosed in children. Childhood PSC undergoing liver transplantation is rarely reported. Here we present a 12-year-old girl who was admitted with a 6-day history of fever, abdominal pain, fatigue, jaundice, and splenomegaly. Liver histological examination revealed the destroyed bile ducts and bridging fibrosis. Endoscopic retrograde cholangiopancreatography (ERCP) showed beaded appearance of right intrahepatic ducts and absent left intrahepatic ducts. PSC was diagnosed. Because of decompensated liver function, she received a living-related orthotopic liver transplantation (OLT). The post-transplantation course was uneventful during the 12-month follow-up. She experienced neither additional episode of cholangitis nor recurrence of liver cirrhosis after OLT.

Abdominal Pain↗
PubMedDate not supplied

Optimal interval from decompression to semi-elective operation in sigmoid volvulus.

BACKGROUND/AIMS: The initial non-operative decompression and subsequent semi-elective operation is a common strategy in managing sigmoid volvulus. However, the optimal interval between decompression and operation is still unclear. METHODOLOGY: From 1994 to 2004, 25 patients operated on for sigmoid volvulus at the National Taiwan University Hospital were enrolled. The treatment strategy and clinical outcome in these patients were retrospectively reviewed and analyzed. RESULTS: Twenty-one patients underwent successful non-operative decompression initially, and the remaining 4 patients underwent emergent operation. Gangrene of the colon was found in 3 patients, and all of them eventually died of medical complications, i.e. multiple organ failure, pneumonia and myocardial infarction. One leakage but no mortality occurred in the patients undergoing semi-elective operation. The rate of postoperative complication was not significantly different between the patients operated on 2 days and more than 2 days after the decompression. CONCLUSIONS: The initial non-operative decompression and subsequent semi-elective operation results in a satisfactory outcome in managing sigmoid volvulus. In the view of surgical result, a two-day interval seems adequate for bowel preparation and optimization of the patient's condition.

Adult↗