Structure-activity relationships for inhibition of inosine monophosphate dehydrogenase by nuclear variants of mycophenolic acid

Structure-activity relationships in the region of the phthalide ring of the inosine monophosphate dehydrogenase inhibitor mycophenolic acid have been explored. Replacement of the lactone ring with other cyclic moieties resulted in loss of potency, especially for larger groups. Replacement of the ring by acyclic substituents also indicated a strong sensitivity to steric bulk. A phenolic hydroxyl group, with an adjacent hydrogen bond acceptor, was found to be essential for high potency. The aromatic methyl group was essential for activity; the methoxyl group could be replaced by ethyl to give a compound with 2-4 times the potency of mycophenolic acid in vitro and in vivo.

Risk factor analysis of patients with chronic hepatitis C in Taiwan

BACKGROUND

Parenteral transmission is the major route for hepatitis C virus (HCV) infection. However, in western countries, 40% of patients with chronic hepatitis C have no apparent risk factor of HCV infection. This study was designed to investigate the possible risk factors of HCV transmission in chronic hepatitis C patients in Taiwan.

METHODS

One hundred and sixty-one consecutive patients with chronic hepatitis C and 161 age- and sex-matched healthy subjects were enrolled. Risk factors, including blood transfusion, injection with nondisposable needles, education status, surgery, dental procedure, tattooing, ear-piercing, sexual behavior and alcoholism, were obtained in every patient through questionnairing and interviewing.

RESULTS

Patients with chronic hepatitis C, compared with healthy controls, had significantly higher rates of previous history of blood transfusion, frequent nondisposable needle injections, and lower education status (43.5% vs. 10.6%, 19.9% vs. 6.2%, 42.2% vs. 23.0%, respectively, all p < 0.05). Univariate logistic regression analysis showed blood transfusion, frequent nondisposable needle injections and low education as significant risk factors of HCV infection (all p < 0.05). Multivariate analysis again revealed them all to be independent significant risk factors associated with HCV infection in chronic hepatitis C patients.

CONCLUSIONS

Parenteral transmission of HCV via transfusion and frequent nondisposable needle injections were the main routes of contracting HCV infection in patients with chronic hepatitis C in Taiwan. Also, people with low education ran the higher risk of transmission by HCV. Meticulous screening of the transfused blood for HCV, usage of disposable needles, and mass public education are important in our efforts to decrease chronic HCV infection in Taiwan.

Effects of verapamil, propranolol, and procainamide on adenosine-induced negative dromotropism in human beings

Adenosine, verapamil, propranolol, and procainamide are widely used antiarrhythmic drugs. The interactions among them are still not known in human beings. Adenosine-induced negative dromotropic effects were assessed by rapid bolus injection of adenosine during constant high right atrial pacing in each patient. The initial dose of adenosine was 0.5 mg and was followed by a stepwise increment of 0.5 mg until atrioventricular (AV) nodal block occurred. The negative dromotropic actions of adenosine were examined in the control state and in the following three protocols in three groups of patients: (1) In 12 patients (group 1), intravenous verapamil, 0.15 mg/kg, was given; (2) In 12 patients (group 2), intravenous propranolol, 0.1 mg/kg, was given; and (3) in 10 patients (group 3), intravenous procainamide, 15 mg/kg, was given. The dose-response curves of adenosine on AV nodal conduction were almost identical in the control state and after verapamil, propranolol, or procainamide injection. However, verapamil, in contrast to propranolol, significantly reduced the dose of adenosine required to produce AV nodal block, from 4.4 +/- 0.7 mg to 2.7 +/- 0.3 mg (p < 0.01). Of note, procainamide exerted no significant effects on adenosine-induced negative dromotropism on AV nodal conduction or AV nodal block. In conclusion, the negative dromotropic effects of adenosine are preserved and independent even in the presence of verapamil, propranolol, or procainamide. Both verapamil and propranolol can exhibit additive effects with adenosine in prolonging AV nodal conduction time; however, only verapamil can reduce the dose of adenosine required to produce AV nodal block. This finding indicates that the dose of adenosine may be reduced for patients who have already been treated with verapamil.

Comparison of clinico-pathological features in hepatitis B virus-associated hepatocellular carcinoma with or without hepatitis D virus superinfection

BACKGROUND/AIMS

Hepatitis D virus superinfection in hepatitis B virus carriers produces additional damage in an already injured liver. Earlier reports noted that the development of hepatocellular carcinoma may be accelerated in hepatitis D virus-superinfected patients. This study aimed to investigate the impact of hepatitis D virus on the clinical course of hepatitis B virus-associated hepatocellular carcinoma.

METHODS

A total of 42 consecutive hepatocellular carcinoma cases seropositive for antibody against hepatitis D virus antigen (anti-HDV) were found from 1986 to 1994; the clinical manifestations, treatment and outcomes were compared with 255 consecutive hepatocellular carcinoma cases seropositive for hepatitis B virus surface antigen but seronegative for anti-HDV.

RESULTS

The mean age was 60 years in both groups of patients. Other features, including sex, duration of follow-up, presence of cirrhosis or ascites, serum biochemistry, status of HBV-e antigen, and gross and microscopic tumor appearance, were not significantly different between the two groups. Though more patients in the anti-HDV-positive group underwent active treatment (operation or transcatheter arterial chemoembolization) than those in the anti-HDV-negative group (54.8% in 42 versus 34.9% in 255 cases, p = 0.02), the cumulative 4-year survival rates (9.5% versus 9.8%) were similar. For the anti-HDV-positive hepatocellular carcinoma patients, tumor size < 5 cm and active treatment were favorable prognostic predictors associated with survival > 18 months.

CONCLUSION

Hepatitis D virus superinfection does not accelerate the development of hepatocellular carcinoma. The clinical manifestations were similar, and the outcome in anti-HDV-positive patients was not worse than in the general HBV-associated hepatocellular carcinoma patients, as long as they were diagnosed at an early stage and actively treated.

Surgical resection of primary hepatocellular carcinoma extending to adjacent organ(s)

Primary hepatocellular carcinoma (HCC) extending to the adjacent organ(s) is sometimes encountered in patients with large, peripherally located tumours. Over a 4-year period, a total of 151 patients received curative resection of HCC at the Surgical Department of Veterans General Hospital-Taipei, Taiwan. Of these patients, 21 underwent hepatic resection combined with en-bloc resection of the adjacent organ(s) because tumour extension was found during operation. Subsequent histological examination of the resected specimens found evidence of HCC invasion into the resected adjacent organ(s) in only nine patients (group I), and the remaining 12 patients showed no evidence of extrahepatic HCC invasion (group II). Twenty-seven HCC patients with clinico-pathologically matched tumours but without extrahepatic extension were selected as controls (group III). One patient in group I died of hepatic failure after the operation. The morbidity rate was 48% in group I and group II patients, and 30% in group III patients. The difference was not statistically significant. On evaluating the clinico-pathological factors, including DNA ploidy status of the tumours, there were no significant differences between tumours with and without extrahepatic invasion. Patients with locally invasive HCC (group I) had disease-free and overall survival rates comparable with those of the patients without local tumour invasion (group II and III). We conclude that HCC with invasion to the adjacent organ(s) does not seem to be directly related to the 'aggressiveness' of the tumour, and extrahepatic infiltration of the tumour does not preclude a chance of cure. Our results underscore the need for en-bloc resection as treatment of choice for these patients.

The involvement of PKC in N-cadherin-mediated adherens junction assembly in cultured cardiomyocytes

Activation of PKC by PMA was shown to promote the separation of chicken cardiomyocytes from each other in culture. Immunofluorescence staining for N-cadherin indicated that PMA, but not its inactive isoform 4 alpha PMA, induces the separation of cardiomyocytes and of co-cultured fibroblasts at intercellular junctional regions. The PMA-induced separation of cardiomyocytes and of co-cultured fibroblasts was inhibited by the PKC inhibitor, H-7. Immunoblot analysis further demonstrated that both PKC iota and PKC lambda were expressed in the cardiomyocyte cultures. While PKC lambda was localized to the cell-cell contact areas between cardiomyocytes, PKC iota was only detectable in the perinuclear cytoplasm of the co-cultured fibroblasts. The present findings suggest the involvement of PKC in regulating N-cadherin-mediated adherens junction formation in chicken cardiomyocytes. The differential distribution of PKC lambda and PKC iota in the cardiomyocytes and in the co-cultured fibroblasts suggests that different PKC isozymes are involved in regulating the assembly of intercellular junctions in these two cell types.

Brain glucose metabolism during non-rapid eye movement sleep in major depression. A positron emission tomography study

BACKGROUND

Depression is characterized by several sleep-related abnormalities shortly before and after sleep onset, such as prolonged sleep latency, loss of stage 3-4 sleep, reduced rapid eye movement (REM) latency, increased nocturnal core body temperature, and abnormal hormone secretion patterns. Sleep deprivation is associated with a temporary improvement in depression. We hypothesized that depressed patients may be "overaroused" and that absolute cerebral glucose metabolism would be elevated during the first nocturnal non-REM sleep period in depressed patients compared with normal controls. In addition, since hypofrontality (greater metabolic activity in occipital compared with frontal cortical activity) has been reported in waking positron emission tomographic studies of depressed patients compared with controls, we predicted significant hypofrontality in depressed patients during the first non-REM period.

METHODS

Positron emission tomography with fludeoxy-glucose F 18 was used to compare 10 unmedicated men with unipolar depression with 12 normal men during the first non-REM sleep period at normal bedtime.

RESULTS

Whole-brain absolute metabolic rate during non-REM sleep was significantly elevated (+47%) in patients compared with controls. Mean absolute cerebral glucose metabolic rate was also higher in every area of the brain in patients compared with normal controls. The greatest significant mean increases were in the posterior cingulate and amygdala (+44%), hippocampus (+37% to +43%), occipital and temporal cortex (+33% to +34%), and pons (+33%). Relative metabolic rates in specific neroanatomical areas, however, varied considerably both within the patient group and between patients and controls. Patients showed significant hypofrontality, particularly in the medio-orbital frontal cortex, compared with controls. Patients also showed significant reductions of relative metabolic rate in the anterior cingulate, caudate, and medial thalamus compared with controls.

CONCLUSIONS

These findings provide further support for the hyperarousal hypothesis of some types of major depressive disorder. Abnormal patterns of cerebral metabolism during non-REM sleep in depressed patients confirmed earlier waking findings of decreased relative frontal and abnormal limbic metabolic activity and striatal metabolism in association with posterior cortical increases.

Immunocytochemical demonstration of a new vimentin-associated protein in 3T3 fibroblasts

Using a xanthophore cytoskeletal preparation as immunogen, we have produced a monoclonal antibody, A2, which recognized a 160 kDa protein in 3T3 fibroblasts. This protein makes up a cytoplasmic filamentous system, which colocalizes with vimentin filaments. When microtubules and actin filaments are dissolved by high salt extraction, staining with antibody A2 is unaffected. Immunoblot analysis confirms that the 160 kDa protein is co-isolated with vimentin during in vivo high salt extraction. Following vinblastine treatment, both the 160 kDa protein and vimentin become localized to perinuclear caps, as do other intermediate filaments and their associated proteins; after vinblastine removal, the immunostaining produced by A2 becomes filamentous. Immunoelectron microscopy demonstrates that antibody A2 stains a filament system with a diameter of about 10 nm. Our observations suggest that the 160 kDa protein may be a new vimentin-associated protein which differs from the intermediate filament-associated proteins previously reported, and is widely distributed in several cell types.

The relationship of adhesion molecules and leukocyte infiltration in chronic tubulointerstitial nephritis induced by puromycin aminonucleoside in Wistar rats

We studied the expression of adhesion molecules on infiltrating leukocytes and tubular cells in chronic tubulointerstitial nephritis associated with puromycin aminonucleoside (PA) nephrosis. Rats received injections of PA (2 mg/100 g body wt) weekly for the first 3 weeks and every other week thereafter. Rats were killed at 0, 3, 5, 8, and 12 weeks after the start of injections. From the third to the fifth week, the initial infiltrating cells in interstitial tissue were mainly CD4+ T lymphocytes. At the fifth week, ICAM-1, CD44, and hyaluronate were expressed on infiltrating cells in interstitial tissue. At the eighth week, the number of infiltrating cells reached a peak and consisted of T lymphocytes (CD4, CD8) and macrophages (ED1, MHC class II, CD11b, and CD18). The severity of interstitial infiltration was correlated with the degree of proteinuria and with ICAM-1 expression. Our results suggest that CD4+ T lymphocytes may contribute to the production of initial tubular injury. Expression of ICAM-1 helps mononuclear cells migrate to the interstitium. In addition, expression of CD44 and hyaluronate may play important roles in the chronicity of tubulointerstitial nephritis.

An annealing mutation operator in the genetic algorithms for RNA folding

An annealing mutation operator in the genetic algorithms (GA) for RNA folding on a MasPar MP-2 has been designed. The mutation probability descends along a hyperbola with respect to the size of the secondary structure, hence the total number of mutations at each generation drops linearly. Especially for long sequences with thousands of nucleotides as opposed to hundreds of nucleotides, the new mutation operator can make the distribution of free energies over all processors on MasPar MP-2 converge only after hundreds of generations. Based upon this new mutation operator, a technique to terminate the GA is also developed. The new mutation operator runs very efficiently. Some variations of the annealing mutation operator are also discussed.

Prognostic factor analysis of fulminant and subfulminant hepatic failure in an area endemic for hepatitis B

In order to determine the criteria in selecting candidates for orthotopic liver transplantation (OLT), we assessed the aetiology and prognostic indicators in 61 patients with fulminant or subfulminant hepatitis during the past 13 years. Several previously reported models of high risk predictors were not suitable for a large portion of our patients with different aetiological and ethnic backgrounds. In the present study, serological markers of various hepatitis viruses were tested and clinical parameters were compared between survivors and non-survivors. Multiple virus infection and multifactorial causes were important in the pathogenesis (48%) of acute liver failure. Among the 13 clinical parameters, six were considered significant on univariate analysis: prothrombin time prolongation (P < 0.001), total bilirubin, creatinine and alpha-fetoprotein (P < 0.01), age and cholesterol (P < 0.05). With stepwise logistic regression using most discriminatory cut-off values, an age of > 43 years (P = 0.0001), total bilirubin levels of > 23 mg/dL (P < 0.005) and prothrombin time prolongation > 19 s (P < 0.0001) were independent predictors of non-survival. When applied to determine the index of poor prognosis, the sensitivity, specificity, positive predictive value, negative predictive value and predictive accuracy were 100, 67, 95, 100 and 95%, respectively, in the presence of any one of these prognostic factors. We conclude that these indicators may be useful for selecting patients with acute liver failure indicated for OLT.

Autoimmune hepatitis in an area endemic for hepatitis B virus infection: a report of three cases

The role of autoimmune hepatitis (AIH) in the pathogenesis of chronic hepatitis is usually neglected, and its prevalence in Taiwan is uncertain. This report described three cases of AIH among consecutive patients with abnormal liver function tests encountered during the past six years. The minimal follow-up period was three years. Two of them were elderly males and one was associated with spontaneous clearance of hepatitis B surface antigen before being recognized as AIH. Though multiple relapses were encountered in two patients, good response to low-dose corticosteroid therapy was evidenced clinically and histologically. The possibility of AIH as the underlying etiology should be considered when other causes of chronic hepatitis are excluded. Prompt recognition and management prevent untoward outcome.

Ruptured hepatocellular carcinoma: treatment strategy and prognostic factor analysis

BACKGROUND

The prognosis of ruptured hepatocellular carcinoma (HCC) is generally poor, but few studies have focused on the analysis of prognostic factors of this catastrophic event.

METHODS

Eighty-four consecutive patients with ruptured HCC were included. Twenty-nine clinical and laboratory variables were correlated to prognosis by using uni- and multivariate analyses.

RESULTS

Epigastralgia and/or right upper quadrant abdominal pain was the most common initial presentation (70%), followed by shock (42%), abdominal distension (27%) and others (17%). Of these 84 patients, 50 patients were treated by supportive measure, 21 by operation and 13 by transcatheter arterial embolization (TAE). The median survival was 13, 30 and 202 days in each group, respectively, and 24 days overall. TAE showed the lowest hemostatic failure rate (20%). Univariate analysis showed that active treatment (operation or TAE), group I tumor with a solitary nodule or single nodule with proliferation into surrounding area, serum creatinine (< or = 1.2 mg/ml), alkaline phosphatase (< or = 95 U/L), alanine aminotransferase (ALT, < or = 40 U/L), total bilirubin (< or = 1.6 mg/ml), initial systolic blood pressure (> or = 90 mmHg), and absence of main portal vein thrombosis were correlated with a survival longer than 90 days (p < 0.05) in univariate analysis. Active treatment, ALT level and initial systolic blood pressure were still significant in multivariate analysis (p < 0.05).

CONCLUSIONS

TAE may help stop the tumor bleeding. Treatment regimen, ALT levels and initial blood pressure are correlated with the prognosis of ruptured HCC.

Gonadotropin-releasing hormone-stimulated calcium mobilization is altered in pituitary cultures from anestrous ewes

GnRH transiently increases intracellular calcium ([Ca2+]i) in pituitary gonadotrophs in culture. This effect is observed within 10 sec of GnRH treatment, lasts 1-5 min, and is thought to be an important intracellular signal leading to the secretion of LH. Recent studies with ovine pituitary cultures uncovered seasonal differences in this transient calcium response to GnRH. This finding led to the hypothesis that anestrus alters the pituitary response to GnRH and prompted this study on seasonal effects on LH secretion and [Ca2+]i mobilization. Inhibin was used to enhance pituitary sensitivity to GnRH. Results showed that pituitary cultures from 16 cycling ewes secreted an average of 9% +/- 2% of stored LH after treatment with 10 nM GnRH (stored LH = 470 +/- 66 ng/million cells); 9% +/- 1% of pituitary cells increased the concentration of [Ca2+]i from 75-150 nM up to 400-1400 nM. When cultures were pretreated with inhibin, GnRH released an average of 15% +/- 3% of stored LH (stored LH = same as above), and 38% +/- 4% of cells transiently increased [Ca2+]i above 400 nM. Results also showed that pituitary cultures from 11 acycling ewes secreted similar percentages of LH although the cells contained less LH to begin with (stored LH = 190 +/- 24 ng/million cells), but absolutely none of these cells (500 counted) increased [Ca2+]i after GnRH treatment, with or without inhibin present. Levels of GnRH receptor mRNA were unchanged by season. These data show that LH secretion and the rapid, transient increase in [Ca2+]i caused by GnRH are uncoupled in the unique situation of anestrus. It is possible, in fact, that these two parameters are not necessarily coupled during estrous conditions and that the transient change in [Ca2+]i is connected with LH synthesis or some other gonadotroph function. The data also show that inhibin can increase GnRH-responding cells up to 38%, a fact suggesting that inhibin may be a differentiation factor capable of transforming multipotent pituitary cells into gonadotrophs in sheep.

Mechanism of hydrogen peroxide and hydroxyl free radical-induced intracellular acidification in cultured rat cardiac myoblasts

After a transient ischemic attack of the cardiac vascular system, reactive oxygen-derived free radicals, including the superoxide (O2-.) and hydroxyl (.OH) radicals can be easily produced during reperfusion. These free radicals have been suggested to be responsible for reperfusion-induced cardiac stunning and reperfusion-induced arrhythmia. Hydrogen peroxide (H2O2) is often used as an experimental source of oxygen-derived free radicals. Using freshly dissociated single rat cardiac myocytes and the rat cardiac myoblast cell line, H9c2, we have shown, for the first time, that an intriguing pHiota acidification (approximately 0.24 pH unit) is induced by the addition of 100 micromol/L H2O2 and that this dose is without effect on the intracellular free Ca2+ levels or viability of the cells. Using H9c2 as a model cardiac cell, we have shown that it is the intracellular production of .OH, and not O2-. or H2O2, that results in this acidification. We have excluded any involvement of (1) the three known cardiac pHi regulators (the Na+-H+ exchanger, the Cl--HCO3 exchanger, and the Na+-HCO3 co-transporter), (2) a rise in intracellular Ca2+ levels, and (3) inhibition of oxidative phosphorylation. However, we have found that H2O2-induced acidosis is due to inhibition of the glycolytic pathway, with hydrolysis of intracellular ATP and the resultant intracellular acidification. In cardiac muscle and in skinned cardiac muscle fiber, it has been shown that a small intracellular acidification may severely inhibit contractility. Therefore, the sustained pHi decrease caused by hydroxyl radicals may contribute, in some part, to the well-documented impairment of cardiac mechanical function (ie, reperfusion cardiac stunning) seen during reperfusion ischemia.

Serum levels of interleukin-8 in alcoholic liver disease: relationship with disease stage, biochemical parameters and survival

BACKGROUND/AIMS

Interleukin-8 (IL-8), a cytokine produced by a host of cells, including monocytes, macrophages, Kupffer cells and hepatocytes, can activate neutrophils. Peripheral neutrophilia and liver neutrophil infiltration are frequently noted in patients with alcoholic liver disease. However, the relationship between IL-8 and different stages of alcoholic liver disease is uncertain. The aim of this study is to determine if a correlation exists between circulating IL-8 levels and biochemical and histological parameters and survival in alcoholic liver disease.

METHODS

Serum levels of IL-8 were determined with an enzyme-linked immunosorbent assay in 166 subjects, consisting of 30 healthy controls, 26 patients with non-alcoholic fatty liver, 15 with alcoholic fatty liver, 32 with alcoholic hepatitis, 30 with alcoholic cirrhosis, 28 with chronic hepatitis B and 5 with chronic hepatitis C.

RESULTS

Serum IL-8 levels were markedly elevated in patients with alcoholic hepatitis (437 +/- 51 pg/ml) when compared with all other groups (p < 0.05). Levels of IL-8 in patients with alcoholic fatty liver, alcoholic cirrhosis and viral hepatitis were higher than those in controls and in patients with non-alcoholic fatty liver. In addition, IL-8 levels were higher in patients who died (p = 0.007), and correlated with biochemical and histological parameters, and severity of liver injury: serum aspartate aminotransferase, alanine aminotransferase, total bilirubin, prothrombin time, indocyanine green retention ratio, tumor necrosis factor-alpha and peripheral neutrophil count in patients with alcoholic hepatitis. After a 2-year follow up, patients with IL-8 above 479 pg/ml had a higher mortality rate in the alcoholic hepatitis group (p = 0.033).

CONCLUSIONS

These findings suggest that IL-8 is activated in alcoholic liver disease, especially in alcoholic hepatitis, and is closely correlated with liver injury. IL-8 levels can reflect the stage and severity of alcoholic liver disease, and may serve as a predictor of survival in patients with alcoholic hepatitis.

A method for screening antisense oligodeoxyribonucleotides effective for mRNA translation-arrest

A transcription and translation coupled reticulocyte lysate system was established for rapid screening of antisense oligodeoxyribonucleotides (ODNs) to determine which are most effective for mRNA translation-arrest. A plasmid containing the target cDNA under the control of the T7 (or SP6) promoter was added to the lysate system in the presence of the T7 (or SP6) RNA polymerase, RNase H, and the antisense ODN under test. Transcription and translation were accomplished in a one-tube reaction. Translation-arrest caused by antisense ODN was evaluated in terms of the amounts of de novo-synthesized, [35S]-methionine or [35S]cysteine labeled target protein measured by gel electrophoresis and autoradiography. The properties of this system and optimal reaction conditions for use in antisense ODN screening were determined. Our method is simpler and more rapid than other in vitro screening methods.

Prevalence and type of precore hepatitis B virus mutants in hepatitis D virus superinfection and its clinical implications

To study the prevalence and type of the hepatitis B e antigen (HBeAg)-negative mutant in hepatitis D virus (HDV) superinfection, the precore region of hepatitis B virus (HBV) was analyzed by cycle sequencing. Of the 58 samples sequenced, 24 were wild type and 34 carried mutants. The precore stop mutation (TAG) at the 28th codon was found in 32 cases, other mutations were found in 7, and double mutations were found in 5. The absence of HBeAg showed a substantial agreement with the presence of mutants (kappa value, 0.74). Of the acute hepatitis patients, HDV replication and clinical manifestations were not significantly different between those with mutant and wild type virus, except that those with mutant virus were older (mean age, 48 vs. 28 years; P < .002). The absence of HBeAg in these patients is mainly due to HDV superinfection in older HBV carriers who already had precore mutant.

Severe hyperbilirubinemia due to acute hepatitis A superimposed on a chronic hepatitis B carrier with glucose-6-phosphate dehydrogenase deficiency

Taiwan is an endemic area for hepatitis A and B virus infections; nearly 90% of adults have serological markers for either virus. Glucose-6-phosphate dehydrogenase (G6PD) deficiency is also common, ranging from 2% to 10%. We report the case of a 36-yr-old chronic HBV male carrier with G6PD deficiency who developed acute viral hepatitis A with severe hyperbilirubinemia and intravascular hemolysis. The hemolysis was in all likelihood the result of recent exposure to sulfa drugs. Fulminant hepatitis was the initial impression, because the peak serum total bilirubin concentration was alarmingly high, at 85.4 mg/dl. Exchange plasmapheresis was fresh frozen plasma was performed, and various laboratory studies gradually returned to near normal laboratory studies gradually returned to near normal over the next 3 wk. The patient made an uneventful recovery 1 month after admission.

Seasonal variation in the incidence of peptic ulcer and esophageal variceal bleeding in Taiwan

BACKGROUND

Seasonal variation of peptic ulcer and peptic ulcer bleeding has been reported in many western countries. To investigate the seasonal variation of peptic ulcer (PU) and esophageal variceal (EV) bleeding in Taiwan, this retrospective study was conducted.

METHODS

Seven hundred and forty-six cases of gastric ulcer (GU) bleeding, 777 cases of duodenal ulcer (DU) bleeding and 264 cases of EV bleeding were recruited from January 1, 1991 to December 31, 1992. Patients were sent to the Medical Emergency Room (MER) for hematemesis and/or melena. Upper gastrointestinal (UGI) endoscopic examinations were completed within 24 hours for all patients.

RESULTS

Significant seasonal variation was found in the incidence of PU and EV bleeding. PU bleeding was most often seen in March and EV bleeding was most often seen in February.

CONCLUSIONS

The possible mechanism for the cyclic change of PU and EV bleeding is unclear, but clearly more manpower is needed during the months of February and March for better management of the increasing number of cases of PU and EV bleeding.

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

To study sexual transmission of hepatitis D virus (HDV), 52 spouses of 56 index patients were observed and HDV genomes from antibody to HDV (anti-HDV)-positive couples were sequenced. Of the spouses, 11 (21%) were serum HBsAg positive, 3 (27%) of whom were also anti-HDV positive. The HDV sequences between spouses were found to be nearly identical (98% to 98.8%) in the region analyzed (nt 911 to nt 1260). Only one couple showed an identity > 90% with the genotype I HDV strains. The HDV sequences of the remaining two couples showed > 95% identity with each other and > 91% homology with genotype II, but they shared only a 73.1% to 73.7% homology with those of the first couple. The regions corresponding to the autocatalytic cleavage sites, the junction between the middle and the carboxyl terminal one-third domains, and the middle domain of the open reading frame for delta antigen on the antigenomic HDV RNA were more conserved with < 19% divergence among the three couples. Interestingly, there was a 56% divergence in the region corresponding to the carboxyl end of the open reading frame for the large delta antigen on the antigenomic HDV RNA. In summary, this study provides a direct nucleotide evidence of a common source of HDV infection in each couple. Despite divergence in the viral nucleotide sequence, both genotypes I and II were found in Taiwan and were transmitted from patients with a history of prostitute contact to spouses through sexual contact.

A monoclonal antibody identifies vimentin filaments in Sertoli cells and in a subset of epithelial cells in the rat epididymis, urinary bladder, and prostate

PURPOSE

We describe a monoclonal antibody (Mab B2) against vimentin filaments in rat Sertoli cells and in a subset of epithelial cells in the rat epididymis, prostate and urinary bladder.

MATERIALS AND METHODS

The immunoreactivity of Mab B2 was examined on cryostat sections and immunoblots and compared with the reactivity of a previously characterized monoclonal antibody against vimentin.

RESULTS

While both antibodies recognized vimentin in Sertoli cells, only Mab B2 recognized vimentin in urogenital tract epithelia.

CONCLUSIONS

Vimentin is expressed in the urogenital tract, and differential reactivities of antibodies may be responsible for conflicting results reported elsewhere for vimentin expression.

Identification of the IMP binding site in the IMP dehydrogenase from Tritrichomonas foetus

The IMP dehydrogenase from Tritrichomonas foetus has been identified as a potential target for antitritrichomonial chemotherapy. The gene encoding this enzyme was expressed in transformed Escherichia coli, and the recombinant protein was purified to homogeneity with an average yield of 3 mg of protein per liter of bacterial culture. Kinetic characterizations verified that the recombinant enzyme is in the authentic native state. 6-Cl-IMP, an irreversible inhibitor of the enzyme, was found to protect cysteine residue 319 of the enzyme against carboxymethylation by iodoacetamide. Radiolabeled IMP was covalently bound to the enzyme during the enzyme-catalyzed reaction via the formation of a specific adduct with cysteine residue 319. It is thus postulated that the conversion of IMP to XMP catalyzed by the IMP dehydrogenase from T. foetus is mediated by a nucleophilic attack of cysteine-319 in the enzyme protein to IMP at, most likely, its 2-position to facilitate a hydride transfer to NAD, resulting in the formation of a covalent intermediate between substrate and enzyme.

Genotyping of hepatitis D virus by restriction-fragment length polymorphism and relation to outcome of hepatitis D

The outcome of hepatitis D virus (HDV) superinfection varies among patients and in different geographical areas. To find out whether HDV genotype affects outcome, we used a simple genotyping method based on restriction-fragment length polymorphism with enzymes XhoI and SacII for cleavage of PCR products of the HDV genome. Of samples from 88 patients studied, the genotypes of 61 were confirmed by two methods--analysis with both enzymes or by combined restriction-enzyme and direct sequencing analyses--with consistent results. No genotype III HDV was detected among these patients. The majority of patients with acute HDV infection (35/41 [85%]) had genotype II HDV. Among the 41 patients with acute infection, four of six with genotype I had fulminant disease compared with two of 35 with genotype II. Among patients in chronic stage, cirrhosis or hepatocellular carcinoma were found in 12 of 18 with genotype I HDV and eight of 29 with genotype II. Thus genotype II was the predominant HDV genotype in this study in Taiwan. Genotype II HDV was less frequently associated with fulminant hepatitis at the acute stage or with an unfavourable long-term clinical outcome at the chronic stage than was genotype I.

Hepatic segmentectomy for curative resection of primary hepatocellular carcinoma

OBJECTIVES

To evaluate the feasibility and results of segmentectomy for curative resection of hepatocellular carcinoma and to compare the clinicopathological findings of the patients according to the tumor location in the liver.

DESIGN

Case series.

SETTING

A tertiary care center.

PATIENTS

Seventy-five patients with Child's grade A or B liver function who had hepatocellular carcinoma that was confined to one segment and who underwent segmentectomy for curative resection of the tumor. The patients were divided into four groups: group P (posterior segmentectomy, n = 23); group A (anterior segmentectomy, n = 10); group M (medial segmentectomy, n = 16); and group L (lateral segmentectomy, n = 26).

MAIN OUTCOME MEASURE

Disease-free survival rate.

RESULTS

Seventy-three percent of the patients had cirrhosis of the liver. The surgical mortality and morbidity rates were 5.3% and 36.0%, respectively. The 1-, 3-, and 5-year disease-free survival rates were 61.9%, 39.1%, and 26.3%, respectively, and were not significantly different among the four groups (P = .86). Group L had the least operative blood loss and shortest operative time when compared with the other three groups (P < .05). The postoperative liver function changes were mild and transient in the four groups of patients. With regard to pathological factors, only tumor size differed among the groups (tumors in group L were significantly larger than those in the other three groups, P < .05). Forty-three percent of the recurrent tumors were solitary in the early stage, with 81% involving the segment(s) adjacent to the resected one and 57% being confined solely to the segment adjacent to the resected segment. Patients having recurrent hepatocellular carcinomas had significantly larger tumors at the time of resection than did those without recurrence (P = .03).

CONCLUSIONS

Hepatic segmentectomy is an effective therapeutic approach for small hepatocellular carcinomas and can be done safely even in patients with chronic liver disease and impaired liver function.