Supportive treatment, resection and transcatheter arterial chemoembolization in resectable hepatocellular carcinoma: an analysis of survival in 419 patients

OBJECTIVE AND DESIGN

Both surgical resection and transcatheter arterial chemoembolization (TACE) are effective treatments for hepatocellular carcinoma (HCC). Few reports have compared the different treatment modalities for resectable HCC based on clinically matched groups. The aim of this study was to compare the survival rate after surgery, TACE or supportive treatment in resectable HCC patients, and also in elderly patients (> or = 70 y/o).

METHODS

From 1984 to 1993, 419 consecutive patients with resectable HCC were included in this study. Of these, 311 (74%) underwent resection of tumours and 46 (11%) refused operation, opting instead for TACE. The remaining 62 (15%) who refused both methods of treatment were given supportive care. Univariate and multivariate analyses for prognostic factors and the 5-year survival rate among the groups were studied.

RESULTS

Both surgical resection and TACE groups had a better 5-year survival rate than the supportive treatment group (43% and 34% vs. 7%). There was no difference in survival between the surgery and TACE groups. However, the 5-year survival rate was 11% in TACE and 41% in the surgical group when the patients were > or = 70. In multivariate analysis, female sex (P = 0.0466), tumour size < or = 3 cm (P = 0.0001), alpha-fetoprotein (AFP) < 400 U/l (P = 0.0036), single tumour (P = 0.0474), serum creatinine < or = 1.5 mg/dl (P = 0.0006) and alkaline phosphatase (AP) < or = 100 U/l (P = 0.0007) are associated with good prognosis for resectable HCC.

CONCLUSION

TACE is an alternative for resectable HCC. Tumour size, tumour number, AFP level, renal function, AP level and female sex are prognostic factors. In elderly people, TACE must be used prudently and has a worse prognosis.

Early metabolic inhibition-induced intracellular sodium and calcium increase in rat cerebellar granule cells

1. Possible mechanisms responsible for the increases in intracellular calcium ([Ca2+]i) and sodium ([Na+]i) levels seen during metabolic inhibition were investigated by continuous [Ca2+]i and [Na+]i measurement in cultured rat cerebellar granule cells. An initial small mitochondrial Ca2+ release was seen, followed by a large influx of extracellular Ca2+. A large influx of extracellular Na+ was also seen. 2. The large [Ca2+]i increase was not due to opening of voltage-dependent or voltage-independent calcium channels, activation of NMDA/non-NMDA channels, activation of the Na+i-Ca2+o exchanger, or inability of plasmalemmal Ca2+-ATPase to extrude, or mitochondria to take up, calcium. 3. The large [Na+]i increase was not due to activation of the TTX-sensitive Na+ channel, the Na+i-Ca2+o exchanger, the Na+-H+ exchanger, or the Na+-K+-2Cl- cotransporter, or an inability of Na+-K+-ATPase to extrude the intracellular sodium. 4. Phospholipase A2 (PLA2) activation may be involved in the large influx, since both were completely inhibited by PLA2 inhibitors. Moreover, melittin (a PLA2 activator) or lysophosphatidylcholine or arachidonic acid (both PLA2 activation products) caused similar responses. Inhibition of PLA2 activity may help prevent the influx of these ions that may result in serious brain injury and oedema during hypoxia/ischaemia.

Localization of isoprenylated antigen of hepatitis delta virus by anti-farnesyl antibodies

Hepatitis delta virus (HDV) is a subviral pathogen that requires pre-existing or concurrent infection with hepatitis B virus (HBV). HDV expresses two forms of a single protein, the delta antigen (HDAg), which are identical except for an additional 19 residues at the C terminus of the large form. Within this C-terminal extension a cysteine residue is isoprenylated; this isoprenylation is critical for interaction with HBV envelope proteins to enable virus assembly and release into the medium. Therefore, large HDAg must be recruited to an extracellular compartment. However, immuno-staining with HDAg-specific antibodies has localized the large antigen mainly to the nucleus and supports the notion that large HDAg suppresses virus replication in the nucleus. Since isoprenylation would increase the hydrophobicity of the protein and may favour transport towards specific membranes, the question remains whether the large HDAg detected in the nucleus carries an isoprenyl group. To address this issue, antibodies against the farnesyl modification were generated to allow direct visualization of the antigen by immunofluorescence microscopy. The anti-farnesyl antibodies specifically stained large HDAg expressed in Huh-7 cells, and the signal was largely restricted to the nucleus; the staining pattern could be superimposed on those of cells stained for large HDAg. The large HDAg translocated into the nucleus was therefore isoprenylated. In addition, antibodies specific for the farnesyl modification should be applicable to the study of other similarly isoprenylated proteins.

Mixed genotypes infection with hepatitis D virus

Heterogeneity of hepatitis C viral (HCV) genomes results in escape from immune clearance. Super-infection or mixed infection of different genotypes of HCV are seen commonly in humans. Hepatitis D virus (HDV) is classified into 3 genotypes. This study was planned to investigate if mixed genotypes infection of HDV occurs in humans. HDV genotyping based on restriction fragment length polymorphism (RFLP) was used to screen 60-99 HDV clones from each case of 7 prostitutes and 11 patients. Mixed infections were diagnosed by the finding of two or more different RFLP patterns in a case and were confirmed by sequencing. Five prostitutes had mixed infections of genotypes IIa and IIb HDV, while only 2 patients had mixed infections of genotypes I and II HDV (P< 0.05). The heterogeneity in nucleotide sequence was generally below 2% among HDV quasi-species from the same subject, while the heterogeneity was 27.7% between genotypes I and II HDV, and 22.8% between genotypes IIa and IIb HDV from a subject with mixed infection. Multiple HDV clones from the spouses of the 2 index cases were also analyzed. One spouse had mixed infection and the other did not, corresponding to the index cases. In cases with mixed genotypes infections, the prevalence of the minor strain was less than 10% of the total colony population analyzed.

Phylogenetic analysis to document a common source of hepatitis D virus infection in a mother and her child

BACKGROUND

Spread of hepatitis D virus (HDV) from mother to infant is rare and nucleotide evidence to document such transmission is lacking. The aim of this study was to screen the children of HDV-infected parents and compare the HDV nucleotide sequence between children and parents by phylogenetic analysis.

METHODS

Fifty-seven children of 28 HDV-infected parents (23 fathers and 5 mothers, including two couples) were enrolled. HDV genomes from sera of HDV-infected parents and their children were cloned and sequenced. Comparison and phylogenetic analysis of HDV genomes were based on a region from nucleotide 911 to 1260. The homology to nucleotide sequence among different genotypes was estimated by phylogenetic analysis.

RESULTS

One of the eight children whose mothers were anti-HDV positive was positive for anti-HDV. Mean heterogeneity among different HDV clones from a single subject ranged from 0.29% to 1.15%. HDV sequences from the mother and her child (referred from southern Taiwan) were nearly identical (99.7%), both showed 92.2-93.4% homology with other genotype II isolates from north Taiwan and 76.3-77.1% homology with genotype I isolates.

CONCLUSIONS

Genotype II HDV is most prevalent in Taiwan. There are significant variations up to 8% in nucleotide sequence among different genotype II HDV clones isolated from patients in northern and southern Taiwan. Phylogenetic analysis revealed that HDV clones from the mother and her child form a monophyletic group, supporting a common source of infection. Susceptible children of HDV-infected mothers should be protected by hepatitis B virus vaccination and active education.

Does eradication of Helicobacter pylori impair healing of nonsteroidal anti-inflammatory drug associated bleeding peptic ulcers? A prospective randomized study

BACKGROUND

Despite the widely accepted view that Helicobacter pylori is the most important cause of peptic ulcer disease, recent studies have suggested that the microbe protects against nonsteroidal anti-inflammatory drug (NSAID)-associated gastroduodenal lesions and promotes ulcer healing. We investigated the effects of H. pylori eradication on the healing of NSAID-associated bleeding peptic ulcers.

METHODS

Chronic NSAID users presenting with peptic ulcer haemorrhage underwent endoscopy to secure haemostasis and to document H. pylori infection by rapid urease test and culture. They were prospectively randomized to receive either omeprazole (20 mg once daily) for 8 weeks or a 1-week course of triple therapy (bismuth subcitrate 120 mg, tetracycline 500 mg, metronidazole 400 mg, all given four times daily) plus omeprazole (20 mg once daily) for 8 weeks. Endoscopy was repeated after 8 weeks. Final H. pylori status was determined by a 13C-urea breath test that was performed at least 4 weeks after discontinuation of omeprazole.

RESULTS

195 H. pylori-infected NSAID users, complicated by bleeding ulcers, were randomized to receive omeprazole alone (102) or triple therapy plus omeprazole (93). 174 patients returned for second endoscopy at 8 weeks (91 in the omeprazole group, 83 in the triple therapy group). Urea breath test was negative in 14% in the omeprazole group vs. 92% in the triple therapy group (P < 0.001). Complete ulcer healing was achieved in 88 (97%) patients in the omeprazole group and 77 (93%) in the triple therapy group (P=0. 31). On intention-to-treat analysis, ulcers were healed in 86% of the omeprazole group and 83% of the triple therapy group (P=0.50). There was no significant difference in the healing rates of gastric or duodenal ulcers between the two groups.

CONCLUSION

Eradication of H. pylori did not impair the healing of NSAID-associated bleeding peptic ulcers.

Functional pancreatic islet cell tumors with liver metastasis: the role of cytoreductive surgery and transcatheter arterial chemoembolization: a report of five cases

Malignant pancreatic islet tumors are slow-growing tumors. Their relatively benign behavior makes aggressive treatment worthwhile. From January, 1987, to January, 1998, five cases of malignant pancreatic islet tumors with liver metastasis were diagnosed at the Veterans General Hospital-Taipei. Of these, three were gastrinomas and the others were vasoactive intestinal peptide (VIPoma, 1 case) and insulinoma (1 case). Four patients (3 with gastrinomas and 1 with insulinoma) had undergone cytoreductive surgery when the diagnosis of metastasis was made. All five patients underwent transcatheter arterial chemoembolization (TACE). All patients had improved symptoms after cytoreductive surgery and TACE. The survival of patients who underwent combined surgery and TACE was 38 and 17 months in the two gastrinoma cases, more than eight months in one gastrinoma case and more than 20 months in the insulinoma case (these 2 patients are still alive). One VIPoma patient who underwent TACE survived for 12 months. In conclusion, treatment for metastatic pancreatic islet cell tumors require a multidisciplinary approach. Metastasis of the tumor is not a contraindication for aggressive therapy. Combined cytoreductive surgery and TACE can relieve symptoms and are of benefit for patients with pancreatic islet cell tumors with liver metastases.

Evidence of transmission of hepatitis B virus to spouses from sequence analysis of the viral genome

Heterosexual contact is one of the common routes of transmission for hepatitis B virus (HBV) among adults in Taiwan, but only a few studies have provided direct evidence at the level of the HBV genome of infected couples with acute non-fulminant hepatitis to document a common source. By cloning and sequencing polymerase chain reaction-amplified HBV-DNA, we analysed the sequences of the conserved region of the surface gene (nucleotide (n.t.) 305-513, representing 6.5% of the viral genome) of HBV in five HBV-infected index patients, their spouses and four randomly selected HBV carriers as controls. Risk factors associated with acute HBV infection in index cases were sexual contact with their spouses within 3 months before the onset of hepatitis. For all five couples, the HBV-infected index patient and the spouse shared a 100% sequence homology of HBV-DNA. In contrast, there was significantly more variation (mean heterogeneity 6.1%, range 1-13.9%) in the amplified region between the five couples and between each couple and the controls (P<0.001). This study demonstrated that sequence analyses can correlate well with epidemiological findings and confirm the value of the molecular approach for linked infections of HBV through heterosexual contact between spouses. Susceptible adults should receive vaccination.

Analysis of T cell receptor Vbeta gene usage during the course of disease in patients with chronic hepatitis B

The T cell receptor (TCR) is a heterodimeric molecule expressed on the surface of T cells and recognizes foreign peptides presented by the major histocompatibility complex on the surface of antigen-presenting cells or virus-infected cells. Analysis of TCR usage by T cells which recognize hepatitis B virus (HBV) provides further insight into the participation of T cell populations during the course of disease. In this study, we examined the T-cell-proliferative response and the TCR Vbeta gene usage of peripheral blood mononuclear cells in 3 patients with clinical evidence typical of chronic hepatitis B. All 3 patients had significant T-cell proliferative responses against HBV core antigen (HBcAg) during the remission stage, while no responses were detected during the acute exacerbation stage. In addition, the TCR Vbeta7 gene was utilized more frequently in T cells recognizing HBcAg during remission, while TCR Vbeta1 and Vbeta2 were utilized at a higher percentage during acute exacerbation. On the contrary, the T cell proliferative response against HBV surface antigen was undetectable and no specific Vbeta gene was utilized more frequently by all 3 patients, regardless of disease state. Our longitudinal studies, although based on a small sample of patients, demonstrate that the population of HBcAg-activated T cells alters during the course of disease in chronic hepatitis B patients.

Prevalence, implication, and viral nucleotide sequence analysis of GB virus-C/hepatitis G virus infection in acute fulminant and nonfulminant hepatitis

The clinical impact of GB virus-C (GBV-C)/hepatitis G virus (HGV) infection on various causes of acute hepatitis and fulminant hepatitis is controversial. In this study, serum samples from 164 patients with acute hepatitis of various causes, 34 asymptomatic hepatitis B virus (HBV) carriers, and 34 healthy adults were tested for GBV-C/HGV RNA by reverse transcription-nested polymerase chain reaction using primers based on the 5'-untranslated region. Nucleotide sequences of GBV-C/HGV RNA from various groups were compared. The prevalence of GBV-C/HGV RNA was significantly higher in patients with acute hepatitis D virus (HDV) superinfection than in HBV carriers or healthy controls (10/37 vs. 2/34, P < 0.02; 10/37 vs. 1/34, P < 0.005). GBV-C/HGV RNA was detected in 11.1% of acute hepatitis A patients, 9.5% of acute hepatitis B patients, 15.8% of acute hepatitis C patients, 12.5% of acute hepatitis E patients, 11.8% of chronic hepatitis B patients with acute exacerbation, and 11.1% in patients with non-A to -E hepatitis; each was not significantly higher than that in HBV carriers or healthy adults. There were no significant differences in gender, age, serum albumin, bilirubin, and alanine aminotransferase levels nor in the occurrence of fulminant hepatitis (6/28 vs. 36/136) between patients with or without GBV-C/HGV RNA. All six patients with fulminant hepatitis who had GBV-C/HGV RNA were complicated by infection with hepatitis B, C, or D. The GBV-C/HGV clones from 21 patients with or without fulminant hepatitis belonged to group 3. No particular strain of GBV-C/HGV was associated with fulminant hepatitis.

Distribution of the cadherin-catenin complex in normal human thyroid epithelium and a thyroid carcinoma cell line

E-cadherin is the major cell-cell adhesion molecule expressed by epithelial cells. Cadherins form a complex with three cytoplasmic proteins, alpha-, beta-, and gamma-catenin, and the interaction between them is crucial for anchoring the actin cytoskeleton to the intercellular adherens junctions. The invasive behavior of cancer cells has been attributed to a dysfunction of these molecules. In this study, we examined the distribution of the cadherin-catenin complex in a Chinese human thyroid cancer cell line, CGTH W-2, compared with that in normal human thyroid epithelial cells. In the normal cells, using immunofluorescence staining, E-cadherin and alpha-, beta-, and gammm-catenin were found to be localized at the intercellular junction and appeared as 135, 102, 90, and 80 kD proteins on Western blots. In CGTH W-2 cells, no E-cadherin and gamma-catenin immunoreactivity was detected by immunofluorescence or Western blotting; alpha- and beta-catenin were detected as 102 and 90 kD proteins on blots but gave a diffuse cytoplasmic immunofluorescence staining pattern in most cells, while beta-catenin was also distributed throughout the cytoplasm in most cells but was found at the cell junction in some, where it colocalized with alpha-actinin. The present data indicate that the loss of cell adhesiveness in these cancer cells may be due to incomplete assembly of the cadherin-catenin complex at the cell junction. However, this defect did not affect the linkage of actin bundles to vinculin-enriched intercellular junctions.

Detection of serum hepatitis B, C, and D viral nucleic acids and its implications in hepatocellular carcinoma patients

The association of viremia, elevated serum alanine aminotransferase (ALT) levels, and hepatocyte inflammatory activity in hepatocellular carcinoma (HCC) patients was studied. Serum samples from 114 HCC patients undergoing surgery were assayed for hepatitis B, C, and D viral nucleic acids by polymerase chain reaction (PCR) prior to surgery. Of these patients, 65 had HBV infection alone, 15 had HCV infection alone, 4 had HDV infection, 20 had HBV and HCV superinfection, 1 had triple viral infection, and 9 were negative for HBV and HCV infections. The prevalence of active viral replication was significantly higher in HCV than in HBV (92% versus 70%; P = 0.006) patients, and significantly higher mean serum ALT levels were also noted in the HCV group than in the HBV group (P = 0.02). The incidence of marked ALT elevation (>200 U/l) was highest in the HCV (27%) and the HDV (25%) groups. Patients in the HCV group were 10 years older than those in the HBV group. Viral superinfection did not accelerate the development of HCC. Viral replication persisted in a significant portion of HCC patients and a higher prevalence of hepatic inflammation was noted in patients with HCV- and, possibly, HDV-related HCC.

Sero-clearance of hepatitis B surface antigen in chronic carriers does not necessarily imply a good prognosis

The incidence of delayed hepatitis B surface antigen (HBsAg) clearance in the natural history of chronic hepatitis B virus (HBV)-infected patients was low. Previous studies regarding the prognosis in such patients were controversial. Among 1,355 chronic carriers from 1985 to 1997, spontaneous HBsAg clearance was observed in 55 patients. During a mean follow-up period of 23 months, 18 (32.7%; all were male subjects) developed serious complications, including 11 with hepatocellular carcinoma (HCC) (9 of them underwent surgical resection), 6 with cirrhosis, and 1 with subfulminant liver failure. The overall cumulative probability of complications was 29.8% at 4 years, and it was higher in males (P = .044) and patients aged 45 years or more (P = .006); the latter carried an 8.6-fold increased risk (95% CI: 1.2-64.6; P = .037) of adverse events. Histories of acute or chronic infection by hepatitis A virus, C virus (HCV), or D virus (HDV) were present in 42% of patients. Patients seropositive for antibodies against HCV (anti-HCV) or HDV (anti-HDV) had higher alanine transaminase (ALT) levels (>40 U/L; P = .008) after sero-clearance. HBV DNA was detectable in 31% of 51 subjects, in 20% of 20 with antibodies against HBsAg, in 40% of 20 with anti-HCV or anti-HDV, and also in an HCC patient's serum and tumor. Staining of liver HBsAg was positive in 30% of 10 HCC patients. In conclusion, our results demonstrated that hepatitis B viremia may persist, and adverse complications were not rare in HBsAg-clearance patients. All such patients should be closely monitored, which may allow for earlier detection of HCC.

Relationships between serum aminotransferase levels, liver histologies and virological status in patients with chronic hepatitis C in Taiwan

In patients with chronic hepatitis C, the relationships between serum alanine aminotransferase (ALT) levels, histological liver injury and serum hepatitis C virus (HCV) RNA titres remain controversial. To evaluate these relationships, 93 Chinese patients with histological diagnosis of chronic hepatitis C were enrolled for this study. Serum ALT levels, HCV-RNA titres and HCV genotypes were examined. The histology was evaluated according to a modified histological activity score based on the degree of periportal necro-inflammation, intralobular necro-inflammation, portal inflammation, total necro-inflammation and fibrosis. The mean serum ALT level was significantly higher in patients with severe intralobular necro-inflammation activity than in patients with mild or no activity (P = 0.013). However, scores of intralobular activity were only weakly correlated with serum ALT levels (r = 0.27) and could not be used to adequately predict ALT values. Serum ALT levels showed no significant correlation with the scores of portal inflammation, periportal necro-inflammation, total necro-inflammation and fibrosis. Also, there was no significant difference in the mean serum ALT level among different serum HCV-RNA levels and HCV genotypes. Serum HCV-RNA titres and genotypes showed no significant correlation with liver histology and serum HCV-RNA titres were only weakly correlated with the total necro-inflammatory score (r = 0.27). In conclusion, although serum ALT levels were higher in patients with more severe intralobular necro-inflammatory activity, the correlation was not strong enough to adequately predict ALT values. Serum HCV-RNA titres and genotypes also showed no significant correlation with serum ALT levels and liver histologies.

PET Scan Findings in a Patient With a Remote History of Exposure to Organic Solvents

This is a single-case study employing positron emission tomography (PET) scanning and neuropsychological assessment on a 47-year-old male with a 15-year history of repeated respiratory and dermal exposure to high levels of organic solvents with at least 750 peak exposures (i.e., solvent "intoxication"). At age 43, he presented with neuropsychological symptoms of a solvent encephalopathy and multiple abnormalities in his peripheral neurological examination but had normal MRI and EEG findings. Four years after cessation of exposure to degreasing and solvent chemicals, the patient produced a grossly abnormal PET scan in which frontal, hippocampal, and parietal hypometabolism were particularly noteworthy. During this same 4-year period of nonexposure, modest improvements in neuropsychological testing were noted, along with substantial improvements in partial seizurelike symptoms. Frontal lobe deficits elicited in testing and from collateral interview, however, did not change. Findings suggest that repeated peak exposures to organic solvents m y result in a neurobehaviorally complex solvent syndrome caused by central nervous system damage that is readily apparent on PET scan, even though it is not evident in either imaging technologies. In addition, the case is the first reported in which functional neuroimaging was employed to study a patient with chronic solvent encephalopathy many years after cessation of solvent exposure.

Characterization and phylogenetic analysis of a novel hepatitis D virus strain discovered by restriction fragment length polymorphism analysis

The hepatitis D virus (HDV) genotypes in 46 HDV-infected patients and 12 prostitutes were screened with Xhol restriction fragment length polymorphism (RFLP) analysis of reverse transcription PCR products of viral genomes and verified by phylogenetic analysis. The amplificates of three (6.5%) patients and two (17%) prostitutes showed a novel RFLP pattern different from those of the three known genotypes. Complete HDV genomic sequence identities between isolates with a novel RFLP and the HDV genotypes I, II and III were 72.3, 77.2 and 63.0%, respectively. Importantly, divergence was mostly seen in various regions related to replication or packaging. The novel isolates formed a monophyletic group (P < 0.05) and were most closely related to genotype II.

Clinical significance of serum auto-antibodies in Chinese patients with chronic hepatitis C: negative role of serum viral titre and genotype

Positive serum anti-nuclear antibody (ANA) and anti-smooth muscle antibody (SMA) have been reported in 10-66% of patients with chronic hepatitis C virus (HCV) infection from Western countries. However, the mechanism involved in this immunological disorder is still unknown. This study was carried out to evaluate the prevalence and clinical significance of positive serum auto-antibodies in Chinese patients with chronic hepatitis C and to assess the role of serum HCV-RNA titre and HCV genotype in the presence of serum auto-antibodies. Serum ANA, SMA and anti-mitochondrial antibody (AMA) were measured in 122 patients with chronic hepatitis C. Clinical, biochemical and virological data (serum HCV-RNA titre and HCV genotype) were compared between patients with and without serum auto-antibodies. Fifty-eight (48%) patients were associated with positive serum auto-antibodies: 42 (34%) positive for ANA, six (5%) positive for SMA, nine (7%) positive for both ANA and SMA and one (1%) positive for AMA. Clinical parameters (age, sex, blood transfusion history), liver biochemical tests, the presence of cryoglobulinaemia or cirrhosis, and the response to interferon treatment were not significantly different between patients with and without positive serum auto-antibodies. Serum HCV-RNA levels and HCV genotypes were also not significantly different between the two groups. Logistic regression analysis showed that none of the previously mentioned parameters were significant predictors to associate with serum auto-antibodies in chronic hepatitis C. We concluded that 48% of Chinese patients with chronic hepatitis C were associated with positive serum auto-antibodies. Hepatitis C virus genotypes and serum HCV-RNA levels were not correlated to the presence of serum auto-antibodies. The clinical significance and actual pathogenesis of this phenomenon remain to be clarified.

The impact of traveling to endemic areas on the spread of hepatitis E virus infection: epidemiological and molecular analyses

Traveling to endemic areas carries a risk of hepatitis E virus (HEV) infection, but no molecular analysis to document sources of infection is available. Eighteen (38%) of 47 patients with acute non-A, non-B, non-C hepatitis were positive for antibody to HEV (anti-HEV), and 9 (50%) of these were also positive for serum HEV RNA by polymerase chain reaction following reverse transcription. Only 1 (5%) of the 21 patients with acute hepatitis A was positive for HEV RNA. Travel to endemic areas (mostly to China; odds ratio, 22.2; 95% confidence interval, 4.7-105.8) and deeper jaundice (odds ratio, 5.2; 95% confidence interval, 1.01-27.2) were the only factors associated with HEV infection in multivariate analysis. The two HEV isolates from two patients who had traveled to China and the HEV isolate from a patient whose travel history was obscure formed a monophyletic group with the isolates from Guangzhou. The HEV isolates from our patients show a homology of 72% to 78% in nucleotide sequence with the Burma, Beijing, India, Pakistan, and Xiangjiang strains; a homology of 81% to 91% with the Guangzhou strains; and a homology of 76% with the Mexico strain. The close relationship between the Taiwan isolates and the Guangzhou strains was further supported by the short Kimura's two-parameter distances among them. In summary, HEV infection does occur in this area. Epidemiological and molecular analyses strongly indicate that most cases of HEV infection originated from travel to HEV-endemic areas.

Limitations of dobutamine for enhancing flow heterogeneity in the presence of single coronary stenosis: implications for technetium-99m-sestamibi imaging

Dobutamine is used as an alternative to exercise in conjunction with 99mTc-sestamibi SPECT perfusion imaging for detection of coronary artery disease. However, the use of quantitative dobutamine 99mTc-sestamibi SPECT imaging for enhanced detection of coronary stenosis has not been established. The goal of this study is to examine the effects of dobutamine stress on regional myocardial blood flow and relative myocardial 99mTc-sestamibi activity in the presence of a single-vessel stenosis.

METHODS

In six open-chest dogs with left circumflex artery stenosis, radiolabeled microspheres were injected during baseline, severe stenosis and peak dobutamine stress (10 microg/kg/min). Technetium-99m-sestamibi was injected intravenously at peak dobutamine. Hearts were excised 20 min after 99mTc-sestamibi injection for SPECT imaging and post-mortem gamma-well counting.

RESULTS

Dobutamine significantly increased heart rate, rate-pressure product and the first derivative of left ventricular pressure. Ischemic zone (left circumflex) myocardial blood flows (in ml/min/g) were: baseline, 0.92 +/- 0.15; stenosis, 0.65 +/- 0.16; and dobutamine, 1.19 +/- 0.38. Nonischemic zone myocardial blood flows were: baseline, 0.99 +/- 0.18; stenosis, 1.01 +/- 0.12; and dobutamine, 1.94 +/- 0.32 (p < 0.01 versus stenosis). Ischemic flows, expressed as percentages of nonischemic flows, were: baseline, 94% +/- 2%; stenosis, 63% +/- 11% (p < 0.05 versus baseline) and dobutamine, 60% +/- 12% (p was not significant versus stenosis). Technetium-99m-sestamibi activity in the ischemic zone (75% +/- 6% nonischemic) underestimated the relative flow deficit produced during dobutamine stress (p = 0.056). Myocardial 99mTc-sestamibi activity correlated with flow when flow was less than 1.0 ml/min/g. At higher flow ranges (1.0 ml/min/g-3.5 ml/min/g), 99mTc-sestamibi did not track flow.

CONCLUSION

In a canine model of flow-limiting, single-vessel stenosis, dobutamine (10 microg/kg/min) did not augment flow heterogeneity. In addition, relative myocardial 99mTc-sestamibi activity underestimated microsphere flow at higher flows induced by dobutamine, leading to underestimation of ischemia. These findings suggest that dobutamine stress 99mTc-sestamibi scintigraphy may underestimate the relative flow deficit.

Well-differentiated thyroid carcinomas: p53 mutation status and microvessel density

BACKGROUND

Risk-stratification schemes exist for well-differentiated thyroid carcinoma and include prognostic factors such as age, sex, extent of tumor, size of tumor, and presence of metastasis. Controversy continues, however, over the aggressiveness of initial surgical intervention because of anecdotal experiences of poor clinical outcomes in low-risk patients. Our objective is to determine the prognostic significance of two biologic tumor markers, the p53 gene mutation and CD34 microvessel density (MVD) count, in well-differentiated tumors of thyroid gland.

METHODS

We selected 38 patients with well-differentiated thyroid carcinomas from the University of Illinois Tumor Registry. Patients had an average clinical follow-up of 10 years. Paraffin-embedded tumor specimens were available for all patients. Immunohistochemistry was performed to identify mutations of the p53 gene (Ab 1801) and to determine the MVD count (CD34).

RESULTS

There were significant increases in MVD counts within thyroid tumor tissue, when compared with surrounding, normal thyroid tissue. There was no significant correlation noted, however, between increased MVD and histology or recurrence rates. There was a trend toward higher MVD counts in tumor specimens of patients initially seen with metastatic lymphadenopathy. The incidence of p53 mutation expression was 28%, and there was no correlation between p53 status and histology, sex, recurrence rate, or survival.

CONCLUSIONS

This study supports the concept of tumor neovascularization but fails to correlate MVD with clinical behavior or pathologic features in well-differentiated thyroid carcinoma. Furthermore, we found that the p53 mutation status was not an independent prognosticator of tumor behavior in these lesions.

[Receptor-mediated endocytosis induced macrophage cytosolic acidification and exocytosis]

The effects of Con A, WGA, Zymosan A on macrophage cytosolic pH and outflow of lysosomal content through exocytosis were studied with SNAFL-calcein and FITC-Dextran on ACAS570. The results showed all three ligands could induce macrophage cytosolic acidification in about 10 min and kept at the same level hereafter; outflow of lysosomal fluorescent probe through exocytosis appeared in 15-20 min. In resting conditions, macrophage lysosomes mainly distributed in cell center; after stimulated for 15 min by three ligands, the number of lysosomes increased in membrane periphery, in 25-30 min lysosomes moved back toward cell center. We proposed that ligands induced lysosomal pH rises was a basic factor for outflow of lysosomal content through exocytosis, cytosolic acidification inhibited receptor-mediated endocytosis. Cytosolic acidification and outflow of lysosomal content through exocytosis were the results of cellular self-regulation and self-protection during receptor-mediated endocytosis.

Diastolic mitral regurgitation secondary to aortic regurgitation--a case report with emphasis on its mechanism

We report on a 68-year-old male case of mitral regurgitation secondary to aortic regurgitation diagnosed using transthoracic echocardiography. A different mechanism of mitral regurgitation secondary to aortic regurgitation is demonstrated in this report. Two-dimensional color Doppler echocardiography may be a useful tool for anatomic evaluation to define its mechanism.

Well-differentiated thyroid carcinomas: p53 mutation status and microvessel density

BACKGROUND

Risk-stratification schemes exist for well-differentiated thyroid carcinoma and include prognostic factors such as age, sex, extent of tumor, size of tumor, and presence of metastasis. Controversy continues, however, over the aggressiveness of initial surgical intervention because of anecdotal experiences of poor clinical outcomes in low-risk patients. Our objective is to determine the prognostic significance of two biologic tumor markers, the p53 gene mutation and CD34 microvessel density (MVD) count, in well-differentiated tumors of thyroid gland.

METHODS

We selected 38 patients with well-differentiated thyroid carcinomas from the University of Illinois Tumor Registry. Patients had an average clinical follow-up of 10 years. Paraffin-embedded tumor specimens were available for all patients. Immunohistochemistry was performed to identify mutations of the p53 gene (Ab 1801) and to determine the MVD count (CD34).

RESULTS

There were significant increases in MVD counts within thyroid tumor tissue, when compared with surrounding, normal thyroid tissue. There was no significant correlation noted, however, between increased MVD and histology or recurrence rates. There was a trend toward higher MVD counts in tumor specimens of patients initially seen with metastatic lymphadenopathy. The incidence of p53 mutation expression was 28%, and there was no correlation between p53 status and histology, sex, recurrence rate, or survival.

CONCLUSIONS

This study supports the concept of tumor neovascularization but fails to correlate MVD with clinical behavior or pathologic features in well-differentiated thyroid carcinoma. Furthermore, we found that the p53 mutation status was not an independent prognosticator of tumor behavior in these lesions.

Bcl-xL functions downstream of caspase-8 to inhibit Fas- and tumor necrosis factor receptor 1-induced apoptosis of MCF7 breast carcinoma cells

Stimulation of the Fas or tumor necrosis factor receptor 1 (TNFR1) cell surface receptors leads to the activation of the death effector protease, caspase-8, and subsequent apoptosis. In some cells, Bcl-xL overexpression can inhibit anti-Fas- and tumor necrosis factor (TNF)-alpha-induced apoptosis. To address the effect of Bcl-xL on caspase-8 processing, Fas- and TNFR1-mediated apoptosis were studied in the MCF7 breast carcinoma cell line stably transfected with human Fas cDNA (MCF7/F) or double transfected with Fas and human Bcl-xL cDNAs (MCF7/FB). Bcl-xL strongly inhibited apoptosis induced by either anti-Fas or TNF-alpha. In addition, Bcl-xL prevented the change in cytochrome c immunolocalization induced by anti-Fas or TNF-alpha treatment. Using antibodies that recognize the p20 and p10 subunits of active caspase-8, proteolytic processing of caspase-8 was detected in MCF7/F cells following anti-Fas or TNF-alpha, but not during UV-induced apoptosis. In MCF7/FB cells, caspase-8 was processed normally while processing of the downstream caspase-7 was markedly attenuated. Moreover, apoptosis induced by direct microinjection of recombinant, active caspase-8 was completely inhibited by Bcl-xL. These data demonstrate that Bcl-xL can exert an anti-apoptotic function in cells in which caspase-8 is activated. Thus, at least in some cells, caspase-8 signaling in response to Fas or TNFR1 stimulation is regulated by a Bcl-xL-inhibitable step.