bluuebunny/crossref_metadata_2025 huggingface dataset:
Methods for detecting functional classifications in neuroimaging data
Authors: Bowman F. DuBois , Patel Rajan , Lu Chengxing
Published: July 2004

Data‐driven statistical methods are useful for examining the spatial organization of human brain function. Cluster analysis is one approach that aims to identify spatial classifications of temporal brain activity profiles. Numerous clustering algorithms are available, and no one method is optimal for all areas of application because an algorithm's performance depends on specific characteristics of the data.K‐means and fuzzy clustering are popular for neuroimaging analyses, and select hierarchical procedures also appear in the literature. It is unclear which clustering methods perform best for neuroimaging data. We conduct a simulation study, based on PET neuroimaging data, to evaluate the performances of several clustering algorithms, including a new procedure that builds on thekth nearest neighbor method. We also examine three stopping rules that assist in determining the optimal number of clusters. Five hierarchical clustering algorithms perform best in our study, some of which are new to neuroimaging analyses, with Ward's and the beta‐flexible methods exhibiting the strongest performances. Furthermore, Ward's and the beta‐flexible methods yield the best performances for noisy data, and the popularK‐means and fuzzy clustering procedures also perform reasonably well. The stopping rules also exhibit good performances for the top five clustering algorithms, and the pseudo‐T2and pseudo‐F stopping rules are superior for noisy data. Based on our simulations for both noisy and unscaled PET neuroimaging data, we recommend the combined use of the pseudo‐F or pseudo‐T2stopping rule along with either Ward's or the beta‐flexible clustering algorithm. Hum Brain Mapp 23:109–119, 2004. © 2004 Wiley‐Liss, Inc.
The national cancer data base report on squamous cell carcinoma of the base of tongue
Authors: Zhen Weining , Karnell Lucy H. , Hoffman Henry T. , Funk Gerry F. , Buatti John M. , Menck Herman R.
Published: July 2004

Background.

This study provides the largest contemporary overview of presentation, care, and outcome for base of tongue squamous cell carcinoma (SCC).

Methods.

We extracted 16,188 cases from the National Cancer Data Base (NCDB). Chi‐square analyses were performed on selected cross‐tabulations. Observed and disease‐specific survival were used to analyze outcome.

Results.

Three‐quarters had advanced‐stage (III–IV) disease. Radiation therapy alone (24.5%) and combined with surgery (26.9%) were the most common treatments. Five‐year observed and disease‐specific survival rates were 27.8% and 40.3%, respectively. Poorer survival was significantly associated with older age, low income, and advanced‐stage disease. For early‐stage disease, surgery with or without irradiation had higher survival than irradiation alone. For advanced‐stage disease, surgery with irradiation had the highest survival.

Conclusions.

Survival rates were low for base of tongue SCC, with most deaths occurring within the first 2 years. Income, stage, and age were significant prognostic factors. In this nonrandomized series, surgery with radiation therapy offered patients with advanced‐stage disease the best survival. © 2004 Wiley Periodicals, Inc. Head Neck 26: 660–674, 2004
Quantitative Measurement of Autoantibodies to Recombinant Mitochondrial Antigens in Patients With Primary Biliary Cirrhosis: Relationship of Levels of Autoantibodies to Disease Progression
Authors: Van Norstrand Michael D. , Malinchoc Michael , Lindor Keith D. , Therneau Terry M. , Gershwin Eric M. , Leung Patrick S.C. , Dickson Rolland E. , Homburger Henry A.
Published: July 2004

We examined the clinical usefulness of measurements of antimitochondrial autoantibodies (AMA) in predicting disease progression in patients with primary biliary cirrhosis (PBC). We determined the relationships between AMA levels measured by indirect immunofluorescence (IF) and those measured by quantitative enzyme immunoassays (EIAs) using recombinant 2–oxo–acid dehydrogenase complex (2–OADC) proteins and the Mayo Risk Score, an established indicator of disease progression in primary biliary cirrhosis (PBC). Results of tests for AMA by either method correlated weakly (

r

= .24 to .30) with disease progression as indicated by Mayo Risk Scores. The levels of AMA to 2–OADC proteins varied by more than 200–fold between patients but remained relatively constant over time in individual patients. Despite being positively correlated with Mayo Risk Score results, the levels of AMA to 2–OADC proteins were not useful for predicting disease progression in individual patients with PBC. In addition, we found no significant differences in the levels of autoantibodies to 2–OADC proteins among patients with different histological stages of disease. Our results show that measurements of AMA by IF or by quantitative EIA methods with recombinant 2–OADC proteins are not useful parameters for predicting disease progression in patients with PBC.
Decreased Anion Exchanger 2 Immunoreactivity in the Liver of Patients With Primary Biliary Cirrhosis
Authors: Medina Juan F. , Martínez-Ansó Eduardo , Vázquez Jaime J. , Prieto Jesús
Published: July 2004

Chloride–bicarbonate anion exchanger 2 (AE2) is expressed in a variety of tissues, including the liver and salivary glands, where it may participate in the generation of hydroionic fluxes into secretions. We have previously reported decreased hepatic levels of AE2 messenger RNA in patients with primary biliary cirrhosis (PBC), a cholestatic condition frequently associated with pluriglandular exocrine failure. Here we investigated the expression of AE2 protein in the liver of PBC patients. Using a monoclonal antibody against an AE2 peptide, immunohistochemistry was performed on liver biopsy specimens from subjects with normal liver (n = 7), patients with PBC (n = 13), and patients with cirrhosis or cholestasis other than PBC (n = 17 and 11, respectively). Immunostaining was graded from 0 to 7, according to its intensity and distribution. AE2 immunoreactivity was observed in normal livers, as previously reported, and in many pathological liver biopsy specimens, being mainly restricted to canaliculi and the luminal membrane of terminal and interlobular bile ducts. Canalicular and ductular scores were significantly reduced in the PBC group compared with each control group (normal liver and cirrhosis or cholestasis other than PBC), whereas no differences in immunoreactivity scores were observed among control groups. When four patients with primary sclerosing cholangitis (PSC) were analyzed, they also differed from those with PBC. These results suggest that PBC is characterized by diminished expression of AE2 in the liver. Reduced levels of this transporter protein might be involved in the pathogenesis of cholestasis in PBC.
Accumulation of Multiple T–Cell Clonotypes in the Liver of Primary Biliary Cirrhosis
Authors: Ohmoto Masaki , Yamamoto Kazuhide , Nagano Takuya , Matsumoto Seiji , Kobashi Haruhiko , Okamoto Ryoichi , Tsuji Takao
Published: July 2004

The histological hallmark of primary biliary cirrhosis (PBC) is the destruction of the interlobular and septal bile ducts accompanied by a dense accumulation of lymphocytes; this constellation of features is termed chronic nonsuppurative destructive cholangitis. To analyze the T cells responsible for bile duct destruction, the T–cell receptor (TCR) Vβ repertoire was studied in liver biopsy specimens, and also in peripheral blood lymphocytes (PBL) obtained from seven patients with PBC in the early stage (Scheuer's stage I or II). The complementary DNA (cDNA) of each TCR Vβ1–20 chain was amplified by reverse–transcription polymerase chain reaction (RT–PCR), and the PCR products were examined by single–strand conformation polymorphism (SSCP) analysis. On the RT–PCR/SSCP analysis, a leukemic cell line, HPB–ALL, showed bands in TCR Vβ 5.2 and Vβ 6, indicating clonal expansion with distinct TCR. In the PBL from healthy subjects, the PCR products were amplified from many TCR Vβ and were shown as smears on SSCP, suggesting that PBL consist of diverse T–cell clones. In PBC, many TCR Vβ products were amplified by RT–PCR in both liver tissues and PBL, and no biased expression of a particular Vβ was observed. SSCP analysis revealed multiple bands in most Vβ chains, suggesting the presence of selected but multiple T–cell clones. Both the number and types of Vβ showing clonal expansion were heterogeneous in the PBC patients. A comparative RT–PCR SSCP analysis of each TCR Vβ between tissue lymphocytes and PBL revealed the presence of some identical T–cell clones in both the PBC liver and the PBL. These results suggest that T cells infiltrating the liver in PBC consist of multiple clonotypes and that T–cell clones accumulated in the liver are also present in PBL.
Cerebral Abnormalities in Patients With Cirrhosis Detected by Proton Magnetic Resonance Spectroscopy and Magnetic Resonance Imaging
Authors: Geissler Angela , Lock Guntram , Fründ Rüdiger , Held Paul , Hollerbach Stephan , Andus Tilo , Schölmerich Jürgen , Feuerbach Stefan , Holstege Axel
Published: July 2004

Hepatic encephalopathy is a common problem in cirrhosis. The pathogenesis of this complication of advanced liver disease still remains unclear. Magnetic resonance spectroscopy was used to assess prospectively cerebral metabolism in 51 patients with histologically proven cirrhosis (Child–Pugh classes A, B, and C, 18, 18, and 15, respectively) and 36 healthy volunteers. According to the results of psychometric tests, overt hepatic encephalopathy, subclinical encephalopathy, and no encephalopathy were found in 14, 21, and 16 patients, respectively. Myoinositol/creatine ratios in gray (.36 ± .17) and white (.35 ± .22) matter voxel were reduced significantly (

P

< .0001) in cirrhotic patients compared with healthy volunteers (gray matter, .51 ± .11; white matter, .64 ± .16). In addition, patients showed a significant reduction (

P

= .024) in white matter choline/creatine ratio (.77 ± .27) compared with controls (.92 ± .25), and glutamine/glutamate level was elevated in cirrhotic patients compared with controls (gray matter,

P

< .0001; white matter,

P

= .036). Changes in cerebral myoinositol and glutamine/glutamate levels correlated significantly with the severity of hepatic encephalopathy (

P

< .0001). However, these metabolic alterations were also detected in patients without hepatic encephalopathy (normal psychometric test results).

N

–acetyl aspartate/creatine ratios did not differ between patients and controls. Magnetic resonance imaging detected bright basal ganglia in 37 patients, which correlated significantly with portal–systemic shunting and elevation of glutamine/glutamate, but not with the degree of hepatic encephalopathy. In conclusion, magnetic resonance imaging and spectroscopy showed that alterations of cerebral metabolism are common in patients with cirrhosis, even without evidence of clinical or subclinical hepatic encephalopathy.
The Hyperventilation of Cirrhosis: Progesterone and Estradiol Effects
Authors: Lustik Stewart J. , Chhibber Ashwani K. , Kolano Jeff W. , Hilmi Ibtesam A. , Henson Lindsey C. , Morris Michael C. , Bronsther Oscar
Published: July 2004

Progesterone and estradiol are metabolized in the liver and are elevated in patients with cirrhosis. Progesterone stimulates ventilation by activating progesterone receptors in the central nervous system; estradiol may facilitate progesterone's actions by increasing progesterone receptors. This study evaluated whether progesterone and estradiol contribute to the respiratory alkalosis common in cirrhotic patients. Arterial blood gases and progesterone and estradiol levels were obtained in 50 patients with cirrhosis. Multiple linear regression revealed a statistically significant correlation between PaCO2 and progesterone and estradiol (

r

= .54,

P

< .05). Patients with severe hyperventilation (PaCO2 ≤ 30 mm Hg) had statistically higher levels of progesterone and estradiol than did patients with mild hyperventilation (30 < PaCO2 ≤ 35) or normal ventilation (PaCO2 > 35) (

P

< .05). Although the progesterone levels were two orders of magnitude lower than those associated with hyperventilation in pregnant patients, the increased ventilatory effect may be because of the altered blood–brain barrier (BBB) present in cirrhotic patients. Progesterone and estradiol appear to contribute to the hyperventilation in cirrhotic patients.
Immune Response to Cyclin B1 in Hepatocellular Carcinoma
Authors: Covini G. , Chan E. K. , Nishioka M. , Morshed S. A. , Reed S. I. , Tan E. M.
Published: July 2004

Proteins expressed by plasmids encoding human cyclins and cyclin–dependent kinase 2 (CDK2) were used as antigens in immunoblotting. Fifteen of 100 patients with hepatocellular carcinoma (HCC) were found to have autoantibodies reactive with cyclin B1 and with a 40–kd degradation product of cyclin B1–glutathione–S–transferase (GST) fusion protein. Only one serum was found to react with cyclin A and another single serum with CDK2 but no antibodies were detected to cyclin D1 and E. The basis for autoimmune responses to cyclin B1 in HCC are unknown at the present time but the possibilities might include aberrations in cyclin B1 regulation leading to altered product or its expression which resulted in stimulation of immune reactions.
Patterns of Recurrence After Initial Treatment in Patients With Small Hepatocellular Carcinoma
Authors: Kumada T. , Nakano S. , Takeda I. , Sugiyama K. , Osada T. , Kiriyama S. , Sone Y. , Toyoda H. , Shimada S. , Takahashi M. , Sassa T.
Published: July 2004

To assess intrahepatic metastasis (IM) and multicentric occurrence (MO) after initial treatment of small hepatocellular carcinomas (HCC) ≤2 cm in diameter, we performed clinical and pathological studies in 112 patients who underwent percutaneous ethanol injection therapy (PEIT) or hepatic resection for HCC from January 1985 to December 1994. Patients with intrahepatic recurrences were classified into two groups based on the type of recurrence: the IM group (n = 29, 50.9%) and the MO group (n = 28, 49.1%). Overall recurrence rates after initial treatment were 23.7% at 1 year, 64.5% at 3 years, and 76.1% at 5 years. In patients with IM, the majority of intrahepatic recurrences were observed within 3 years of initial treatment and the primary HCC lesions were closely related to the degree of tumor cell differentiation. Alternatively, intrahepatic recurrences occurred throughout the follow–up period in patients with MO, and the evidence of underlying liver disease (anti–HCV [antibody to hepatitis C virus] positive) and elevated serum alfa–fetoprotein (AFP) concentrations were closely associated with intrahepatic recurrence. Prognoses following additional treatment in MO group patients were superior to those in IM group patients. These results suggest that differentiation between IM and MO in patients with HCC is important for understanding the development and biological behavior of the tumor. That is, the early detection of intrahepatic recurrence and the institution of appropriate additional therapy (PEIT or hepatic resection) may prolong survival in patients with MO.
Induction of Hepatocyte Growth Factor Activator Messenger Rna in the Liver Following Tissue Injury and Acute Inflammation
Authors: Okajima A. , Miyazawa K. , Naitoh Y. , Inoue K. , Kitamura N.
Published: July 2004

Hepatocyte growth factor activator (HGFA) is a serine protease that is responsible for localized activation of hepatocyte growth factor (HGF) in injured tissue. The activated HGF may be involved in regeneration of the injured tissue. HGFA is produced and secreted by the liver and circulates in the plasma as an inactive zymogen. In response to tissue injury, the HGFA zymogen is converted to the active form by limited proteolysis. In this study, we isolated a rat HGFA complementary DNA (cDNA) clone and analyzed the production of HGFA messenger RNA (mRNA) in response to tissue injury using this cDNA clone as a probe. The nucleotide sequence of the cDNA revealed that the amino acid sequences of rat and human HGFA showed a high degree of conservation in the regions of the characteristic domain structures, suggesting that rat and human HGFA are activated by a similar mechanism and have similar enzymatic activities

in vivo

. Tissue distribution analysis showed that the liver was the major site of rat HGFA mRNA synthesis. Moreover, the cells producing HGFA mRNA were identified as parenchymal liver cells. The level of HGFA mRNA increased in the liver after hepatotoxin or nephrotoxin treatment. This increase was also observed during acute inflammation induced by turpentine. These results suggest that the increase in production of HGFA mRNA in response to tissue injury is the result of an inflammatory response, and that HGFA is an acute phase protein.
Hepatic Injury During Ketoconazole Therapy in Patients With Onychomycosis: A Controlled Cohort Study
Authors: Chien R. , Yang L. , Lin P. , Liaw Y.
Published: July 2004

To evaluate the incidence, severity, and course of ketoconazole– associated hepatic injury, 211 patients with onychomycosis were randomized by a ratio of 2:1 to receive either ketoconazole (137 patients) or griseofulvin (74 patients). All of them were seronegative for hepatitis B surface antigen (HBsAg) and anti–hepatitis C virus (HCV) and had no biochemical abnormality before therapy. The two groups were comparable in age, sex, and pretherapy liver biochemical tests. Liver biochemical tests were followed up biweekly for 3 months, and then at monthly intervals during the remaining course of therapy. No biochemical abnormality or hepatic injury was found in patients during griseofulvin treatment. Of the patients treated with ketoconazole, 24 (17.5%; 95% confidence interval [CI], 11.1% to 23.9%) showed asymptomatic transaminase elevation. Ketoconazole was discontinued immediately after overt hepatitis developed in another 4 patients (2.9%; 95% CI, 0.1% to 5.7%) who did not succumb to hepatic decompensation. The abnormal biochemical changes in patients with overt hepatitis returned to normal after discontinuing ketoconazole. Elderly patients were more prone to develop overt hepatitis. In patients with asymptomatic liver injury, the abnormal biochemical changes gradually returned to normal despite continuing ketoconazole therapy. The results of this cohort study suggest that ketoconazole–induced overt hepatitis is more common than previously believed and that transient subclinical injury is much more common than overt hepatitis. Therapy with ketoconazole may be continued with caution in the absence of symptoms and/or hyperbilirubinemia, but should be discontinued if overt hepatitis occurs.
Excess Weight Risk Factor for Alcoholic Liver Disease
Authors: Naveau S. , Giraud V. , Borotto E. , Aubert A. , Capron F. , Chaput J.
Published: July 2004

Though the hepatotoxicity of ethanol has been established, only 8% to 20% of chronic alcoholics develop cirrhosis. The aim of this study was to assess whether being overweight is a risk factor for alcoholic liver disease. One thousand six hundred four alcoholic patients were studied. According to the liver biopsies, 194 patients had a normal liver; 402 had steatosis without fibrosis; 281 presented with fibrosis, with or without steatosis; 119 presented with acute alcoholic hepatitis (AAH) without cirrhosis; 232 indicated cirrhosis without AAH; and 179 presented with cirrhosis with AAH. One hundred ninety–seven patients had clinically obvious cirrhosis. In the study, five variables were studied as risk factors: age, sex, daily consumption of alcohol during the previous 5 years, the total duration of alcohol abuse, and tendency to be overweight (body mass index [BMI] ≥ 25 in women and ≥ 27 in men). The BMI was calculated according to the minimum weight over the 10 previous years. In the first stepwise logistic regression analysis, age, being overweight for at least 10 years, being of the female sex, and the total duration of alcohol abuse were independently correlated with the presence of cirrhosis. In the second analysis, female sex being overweight were the two independent risk factors of AAH. In the third analysis, being overweight for at least 10 years was the only independent risk factor of steatosis. These results show that the presence of excess weight for at least 10 years is a risk factor for cirrhosis, AAH, and steatosis. Our results suggest that there is a possible potential for the metabolic effects of ethanol ingestion caused by excess weight in patients with alcoholic liver disease.
Alcoholism and Alcoholic Organ Damage and Genetic Polymorphisms of Alcohol Metabolizing Enzymes in Chinese Patients
Authors: Chao Y. , Young T. , Tang H. , Hsu C.
Published: July 2004

It is still not clear why some alcoholic patients acquire certain organ–specific complications of alcoholism whereas other alcoholic patients acquire different ones. As we know the liver alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), and cytochrome P4502E1 (P4502E1) are polymorphic at the ADH2, ADH3, and ALDH2 loci and the 5′–flanking region of the P4502E1. The aim of this study was to investigate the differences between Chinese alcoholic patients with cirrhosis and acute pancreatitis by studying the genetic polymorphisms of ADH2, ADH3, ALDH2, and P4502E1. Genotyping of ADH2, ADH3, ALDH2, and P4502E1 was performed using polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) methods on peripheral white blood cell DNA from 75 alcoholic cirrhotic patients, 48 acute alcoholic pancreatitis patients, 19 heavy drinkers without liver disease or pancreatitis, and 235 controls. The results showed that the frequencies of the alleles ADH2*1 and ALDH2*1 in the alcoholic cirrhotic patients were significantly higher than those in the nonalcoholic controls. In acute alcoholic pancreatitis patients, only the frequency of allele ALDH2*1, not ADH2*1 was significantly higher than in the nonalcoholic controls. The allele frequency of ADH2*1 in acute pancreatitis patients was significantly lower (

P

< .01) than in alcoholic cirrhotic patients. The daily amount of alcohol consumption was significantly lower in patients with acute pancreatitis than in patients with cirrhosis (

P

< .0005). The genotype distributions of P4502E1, detected by

RsaI

and

PstI

, were not different among alcoholic cirrhotic patients, alcoholic pancreatitis patients, heavy drinker, and nonalcoholic controls. In conclusion, ALDH2*1 is the most important alcohol metabolizing gene affecting predisposition to alcoholism whereas the ADH2*2 gene may influence susceptibility to acute alcoholic pancreatitis. The patients with alcohol–induced cirrhosis and with alcohol–induced acute pancreatitis are of two different subpopulations.
Induction of Early–Immediate Genes by Tumor Necrosis Factor α Contribute to Liver Repair Following Chemical–Induced Hepatotoxicity
Authors: Bruccoleri A. , Gallucci R. , Germolec D. R. , Blackshear P. , Simeonova P. , Thurman R. G. , Luster M. I.
Published: July 2004

We and others have shown that tumor necrosis factor α (TNF–α) expression is increased in the livers of experimental animals following exposure to the chemical hepatotoxin, carbon tetrachloride (CCl4). Because TNF–α is involved in mediating inflammatory responses, its elevated expression is presumed to be associated with potentiating hepatotoxicity and/or aiding in liver repair processes. To study the role of TNF–α in chemical–induced hepatotoxicity, mice were administered neutralizing antibodies to TNF–α before administration of low, but hepatotoxic, doses of CCl4. Antibody treatment prevented CCl4–mediated increases in early–immediate gene expression associated with liver regeneration, including expression of c–

jun

and c–

fos

proto– oncogenes, as well as DNA binding of the activator protein–1 (AP–1) nuclear transcription factor. Hepatocyte proliferation following CCl4 treatment was also reduced in anti–TNF–α antibody–treated mice, as evidenced by a lack of proliferating cell nuclear antigen (PCNA) staining. Antibody treatment slightly delayed liver repair processes, as evidenced by extending the period in which plasma liver enzyme levels were increased and hepatocellular necrosis could be observed. Consistent with the above observations, injection of recombinant TNF–α into control mice induced rapid expression of c–

jun

and c–

fos

proto–oncogenes. Taken together, these results indicate that TNF–α positively modulates liver recovery following CCl4 exposure presumably by stimulating early–immediate genes involved in hepatic mitogenesis, a phenomenon also observed following partial hepatectomy.
4–Hydroxynonenal Levels Are Enhanced in Fetal Liver Mitochondria By In Utero Ethanol Exposure
Authors: Chen J. J. , Schenker S. , Henderson G. I.
Published: July 2004

Lipid peroxidation has been implicated in ethanol–induced liver injury and observed in fetal liver and brain after maternal ethanol consumption with mitochondria being the target organelles. This process generates a highly reactive and toxic product, 4–hydroxynonenal (HNE). In the present study, HNE levels and metabolism were assessed in mitochondria of fetal and maternal liver after

in vivo

ethanol exposure. Female Sprague–Dawley rats received five doses of ethanol (4 g/kg orally at 12–hour intervals) and were killed on day 19 of gestation. The results showed that HNE levels were enhanced in hepatic mitochondria of fetal rats exposed to ethanol, far in excess of that in adult liver mitochondria. Measurement of HNE metabolism showed that fetal mitochondria had a lower capacity for HNE catabolism than adult mitochondria. In adult mitochondria, HNE could be metabolized by nicotine adenine dinucleotide–dependent oxidation, reduced glutathione conjugation, and reduced nicotine adenine dinucleotide–dependent reduction, whereas in fetal liver only the former two pathways were active, but to a lesser degree than in adult mitochondria. On the other hand, mitochondria from fetal liver showed a higher production of HNE when oxidative stress was induced with t–butyl hydroperoxide. Prior

in vivo

ethanol exposure further potentiated HNE formation in t–butyl hydroperoxide–stimulated fetal liver mitochondria, but not in adult mitochondria. These findings indicate that increased levels of HNE in fetal liver mitochondria after maternal ethanol consumption reflect a higher susceptibility to HNE formation in addition to a lesser capacity to metabolize it. The enhanced accumulation of this toxic aldehyde may contribute to oxidative damage observed in fetal tissues after

in utero

ethanol exposure.
The Frequency of Hemochromatosis–Associated Alleles Is Increased in British Patients With Sporadic Porphyria Cutanea Tarda
Authors: Roberts A. G. , Whatley S. D. , Nicklin S. , Worwood M. , Pointon J. J. , Stone C. , Elder G. H.
Published: July 2004

The cause of the hepatic siderosis and iron overload that is common in porphyria cutanea tarda (PCT) is uncertain. Heterozygosity for genetic hemochromatosis has been supported by some studies of the association between the HLA–A3 antigen and porphyria cutanea tarda but not by others. The hemochromatosis gene is now believed to be located telomeric to HLA–A3 and close to the DNA microsatellite marker D6S1260. We have used this and other microsatellite markers, which together define an ancestral haplotype that is strongly linked to hemochromatosis, to reinvestigate the relationship between these disorders in 41 British patients with sporadic PCT. Fifteen patients carried the hemochromatosis–associated alleles D6S265–1 and D6S105–8. Four of these were homozygous for the ancestral haplotype D6S265–1: D6S105–8: D6S1260–4. We estimate that approximately 37% of British patients with sporadic PCT carry at least one hemochromatosis gene compared with 10% of the general population.
The Relationship Between Iron Overload, Clinical Symptoms, and Age in 410 Patients With Genetic Hemochromatosis
Authors: Adams P. C. , Deugnier Y. , Moirand R. , Brissot P.
Published: July 2004

The aim of this study was to investigate the relationship between iron overload, age, and clinical symptoms in genetic hemochromatosis. The relationship was studied between clinical symptoms and liver iron concentration, serum ferritin, and iron removed in a retrospective study of 410 homozygotes diagnosed using strict criteria. No significant relationship was found between liver iron concentration, iron removed by venesection, and serum ferritin level with age. The prevalence of cirrhosis, diabetes, cardiac disease, pigmentation, and fatigue increased as liver iron concentration increased. The most common presentations at diagnosis were fatigue or as an incidental finding in all age groups. Twenty–seven percent of patients (110 of 410) had no clinical symptoms of hemochromatosis. Iron accumulation is highly variable in patients with genetic hemochromatosis. The significant relationship between liver iron concentration and cirrhosis, diabetes, cardiac disease, pigmentation, and fatigue confirms the importance of iron toxicity in the pathogenesis of hepatic and extrahepatic disease. The nonspecific nature of the presenting features in patients and the presence of significant clinical symptoms in patients discovered through family investigations underscore the importance of family and population screening for hemochromatosis.
Repolarization of Hepatocytes in Culture
Authors: Talamini M. A. , Kappus B. , Hubbard A.
Published: July 2004

We have evaluated the biochemical, morphological, and functional redevelopment of polarity in freshly isolated hepatocytes cultured using a double layer collagen gel sandwich technique. Western blot analysis showed increased cellular levels of the cell adhesion protein uvomorulin as cultured hepatocytes repolarized. Immunofluorescence studies using antibodies against domain–specific membrane proteins showed polarity as early as 48 hours, although the pattern of the polymeric Immunoglobulin–A receptor (pIgA–R) differed from

in vivo

liver. Electron microscopy showed developing bile canaliculi at 1 day. However, the functional presence of tight junctions was absent at 1 day, but present at 5 days. We further showed functional polarity to be present at 4 days by documenting the ability of cultured hepatocytes to metabolize and excrete fluorescein diacetate into visible bile canaliculi. We conclude that hepatocytes cultured appropriately develop morphological and functional polarity. Hepatocyte culture is therefore a useful tool for the study of mechanisms responsible for the development of polarized function.
Prednisone Withdrawal Late After Adult Liver Transplantation Reduces Diabetes, Hypertension, and Hypercholesterolemia Without Causing Graft Loss
Authors: Stegall M. D. , Everson G. T. , Schroter G. , Karrer F. , Bilir B. , Sternberg T. , Shrestha R. , Wachs M. , Kam I.
Published: July 2004

We prospectively withdrew prednisone in 28 adult patients who had stable graft function more than 2 years after orthotopic liver transplantation (OLTx) and had been on 5 mg/d prednisone for at least 6 months. Prednisone was decreased from 5 mg/d to 2.5 mg/d for 1 month then stopped completely. Cyclosporine monotherapy was maintained at a level of approximately 200 ng/mL (TDX). Nineteen patients had prednisone withdrawn without complications. Four (14.2%) had modest elevations in liver function tests (two biopsy proven mild rejections and two were not biopsied). These four were treated with methylprednisolone boluses and then withdrawal of steroids again. Prednisone was restarted in five patients because of generalized fatigue and body aches (n = 4) and colitis (n = 1). Steroids later were successfully withdrawn in two of these patients. After prednisone withdrawal, three of five insulin–dependent diabetic patients were able to discontinue insulin therapy and their glycosylated hemoglobin levels improved. Four of fourteen hypertensive patients were able to discontinue antihypertensive medicines. Mean serum cholesterol decreased from 222.6 ± 43.3 to 188.3 ± 33.3 mg/dL (

P

< .001). The number of patients with serum cholesterol levels > 220 mg/dL decreased from 13 to 4. A control group of 24 patients maintained on 5 mg/d prednisone at least 2 years after liver transplantation also was studied. In this group during the study period, no diabetic became normoglycemic, no patient decreased their antihypertensive medicine, and the mean serum cholesterol levels did not change significantly. We conclude that prednisone withdrawal using cyclosporine monotherapy late after liver transplantation does not lead to graft loss and decreases the prevalence of diabetes, hypertension, and hypercholesterolemia. Symptoms occurring during withdrawal may be minimized by earlier or slower tapering. (Hepatology 1997 Jan;25(1):173–7)
Changes in Adipose Tissue Composition in Malnourished Patients Before and After Liver Transplantation: A Carbon–13 Magnetic Resonance Spectroscopy and Gas–Liquid Chromatography Study
Authors: Thomas E. L. , Taylor-Robinson S. D. , Barnard M. L. , Frost G. , Sargentoni J. , Davidson B. R. , Cunnane S. C. , Bell J. D.
Published: July 2004

We investigated adipose tissue fatty acid composition in 22 moderately to severely malnourished patients with cirrhosis and in 22 healthy volunteers by

in vivo

carbon–13 magnetic resonance spectroscopy (MRS). Gas–liquid chromatography (GLC) of adipose tissue samples was also performed in 11 of the patients and in 4 volunteers.

In vivo

13C magnetic resonance spectra were obtained from the subcutaneous adipose tissue before and after eight weeks following orthotopic liver transplantation (OLT). Adipose tissue biopsy samples were obtained for GLC analysis at the time of transplantation in the patients and at inguinal hernia repair in the 4 volunteers. No significant differences were found in the subcutaneous adipose tissue total–saturated, – polyunsaturated or –monounsaturated fatty acid composition between patients and healthy volunteers by

in vivo

13C MRS. GLC analysis of adipose tissue samples confirmed that total levels of saturated, poly–, and monounsaturated fatty acids remained the same but revealed significant differences in levels of individual fatty acids, particularly n–3 fatty acids (total n–3, cirrhotics: .84% ± .07% vs. controls: 1.36% ± .13%,

P

< .01). Eight weeks following transplantation, recipients showed a considerable increase in body mass (pretransplantation: 59.3 ± 3.2 vs. posttransplantation: 63.2 ± 3 kg,

P

< .01). 13C MRS revealed a significant increase in saturated fatty acids (pretransplantation: 21.6 ± 2.8 vs. posttransplantation: 25.5% ± 1.2%,

P

< .05) and a significant decrease in unsaturated fatty acids. The application of noninvasive MRS techniques may be important to identify the differential uptake of fats, examining both specific fatty acids and different body fat compartments. In the future, this may be useful in optimizing the dietary management of severely malnourished patients with chronic liver disease before liver transplantation.
Persistent Cytomegalovirus in Liver Allografts With Chronic Rejection
Authors: Lautenschlager I. , Höckerstedt K. , Jalanko H. , Loginov R. , Salmela K. , Taskinen E. , Ahonen J.
Published: July 2004

Cytomegalovirus (CMV) infection is one of the suggested risk factors for chronic allograft rejection. Clinical and experimental studies have shown that CMV is somehow implicated in rejection mechanisms and in the generation of graft arteriosclerosis, characteristic of chronic rejection. In liver transplantation, there is also evidence of an association between CMV and vanishing bile duct–syndrome (VBDS), which is characteristic of chronic liver allograft rejection. In this study, the role of posttransplant CMV infection and of acute rejection in the patients with irreversible, histologically confirmed chronic liver rejection with VBDS and vasculopathy was analyzed. Ten of 200 (5%) consecutive liver transplants were lost due to chronic rejection, from between 5 and 28 months from transplantation. In these 10 patients, acute rejections were frequent, and nine of ten patients had at least one episode of rejection early after transplantation. All patients (10 of 10) had a history of CMV infection usually following acute rejection. To investigate the role of CMV in chronic rejection, nine available removed grafts were examined for the presence of the CMV genome by DNA–hybridization

in situ

using a biotinylated CMV–DNA probe. Persistent CMV–DNA was found in all of those available grafts with chronic rejection. CMV–DNA was strongly expressed in the remaining bile ducts and moderately expressed in the endothelial cells of the vascular structures, the CMV positivity of hepatocytes varied from graft to graft. Thus, persistent CMV genome was found in those structures that are the major targets of the chronic rejection process in the liver. These findings support the previous suggestion of an association between CMV and chronic allograft rejection.
Long–Term Outcome of Hepatitis C Virus Infection After Liver Transplantation
Authors: Böker K. H. , Dalley G. , Bahr M. J. , Maschek H. , Tillmann H. L. , Trautwein C. , Oldhaver K. , Bode U. , Pichlmayr R. , Manns M. P.
Published: July 2004

We analyzed the long–term clinical course of 71 patients with RNA–positive hepatitis C virus (HCV) infection after liver transplantation. Patients with reinfection after transplantation for HCV–related liver disease, or de novo infection at transplantation were followed for up to 12 years. Cumulative survival for patients with HCV infection at 2, 5, and 10 years after transplantation was 67%, 62%, and 62%, respectively. It was not significantly different from that in patients transplanted for other nonmalignant diseases without HCV infection. The main factor determining long–term survival was the presence or absence of hepatocellular carcinoma (HCC) at transplantation. The 5–year survival rate for HCV patients with or without HCC was 35% versus 73%, respectively (P < .05). No deaths because of viral hepatitis of the graft were observed. Deaths in the first year after transplantation were caused by infectious complications, cardiovascular problems, or rejection; deaths after more than 12 months were exclusively because of recurrence of HCC. Biochemical and histological evidence of hepatitis was found in the majority of the patients, only 16% had normal alanine aminotransferase (ALT) values throughout. Twenty–two percent of patients complained of symptoms, with hepatitis C being the cause in 82% of these. Two patients lost their HCV–RNA for prolonged, ongoing periods of time. The severity of the posttransplantation hepatitis was unrelated to age, sex, severity of liver disease before transplantation, cold ischemic time of the graft, duration of the operation, transfusions, the number of rejection episodes, or the long–term immunosuppressive regime. Only initial short–term therapy with interleukin 2 (IL2) receptor antibodies adversely influenced inflammatory activity. Viral genotype did not influence the course of the graft hepatitis in our series. Histology showed inflammation in 88% of the biopsies and signs of fibrosis in 24%. Mean ALT values correlated with inflammation but not with fibrosis in the biopsies. Porto–portal bridging was observed in six patients, one patient developed cirrhosis within 2 years after orthotopic liver transplantation (OLT). We conclude that chronic hepatitis develops in the majority of patients with HCV infection after liver transplantation. Carrier states without significant laboratory abnormalities are observed in approximately 16%, biochemical abnormalities without symptoms are seen in 60%, and symptomatic disease develops in a quarter of the patients. The disease course closely resembles that seen in nontransplanted hepatitis C patients. It is generally mild but little over 10% of patients develop signs of fibrosis of the graft during the first decade.
Lack of Correlation Between Hepatitis C Virus Genotypes and Clinical Course of Hepatitis C Virus–Related Cirrhosis
Authors: Benvegnù L. , Pontisso P. , Cavalletto D. , Noventa F. , Chemello L. , Alberti A.
Published: July 2004

The influence of the hepatitis C virus (HCV)–genotype on liver disease severity was evaluated in 429 consecutive patients with chronic hepatitis C, including 109 with cirrhosis who were followed up prospectively, allowing for the assessment of the role of the HCV–genotype on disease outcome and on the development of hepatocellular carcinoma (HCC). HCV–1 was detected in 147 (46%) patients without cirrhosis and in 47 (43%) with cirrhosis (x not significant), being mainly HCV–1b. HCV–2 was found in 103 (32%) cases without cirrhosis and in 30 (27.5) with cirrhosis (

P

: not significant), being mainly HCV–2a. HCV–3 was detected in 32 (10%) patients without cirrhosis and in 2 (2%) with cirrhosis (

P

< 0.005). Infection with more than one genotype (HCV–1/HCV–2 and HCV–1/HCV–3) was observed only in cirrhotic patients (6 of 109; 5.5%). During a mean follow–up of 67 ± 22 months, 21 (19%) patients with cirrhosis showed worsening in Child's stage, 5 (4.5%) underwent liver transplantation, 23 (21%) developed HCC, and 24 (22%) died of complication of liver disease; the overall incidence of at least one of these events was 38.5%. By the Kaplan–Meier method and log–rank test, the cumulative probability of developing each or at least one of the above events did not differ in relation to the genotype of infecting HCV, apart from patients with mixed genotype infection who showed a significantly higher incidence of death (

P

< .05). These data indicate that HCV–genotypes do not have a significant effect on the severity and outcome of liver disease in patients with chronic HCV–infection. Patients with cirrhosis who are also infected by HCV–1 and HCV–2 had a similar prognosis and progression to HCC, while patients infected by more than one genotype showed the most unfavorable course of disease.
Detection by Ligase Chain Reaction of Precore Mutant of Hepatitis B Virus
Authors: Minamitani S. , Nishiguchi S. , Kuroki T. , Otani S. , Monna T.
Published: July 2004

The clinical diagnosis of infection with the most common precore mutant of hepatitis B virus (HBV), that with a point mutation from guanine to adenine at nucleotide 83 in the precore region, is important because the disease may progress rapidly despite interferon therapy. A practical method to detect this mutant is needed. With the ligase chain reaction (LCR), target DNA sequences can be amplified and single base mutations can be detected. We tried to detect mutant HBV by the LCR alone, but the limit of detection (109 copies per tube) was too high. To increase the sensitivity, we used the LCR on DNA already amplified by the polymerase chain reaction (PCR), and tested serum samples from 23 subjects with chronic HBV infection for mutant and wild–type HBV. As few as 102 copies per tube could be detected. The results corresponded with the results of nucleotide sequencing for 22 of the 23 patients. The ratio of clones of mutant and total viruses was estimated for each individual by PCR–coupled LCR. Seroconversion could be identified earlier in the illness by an increase in this ratio than by the decrease in HBeAg. We also tested serum samples from 11 patients with acute liver failure by PCR–coupled LCR. Mutant HBV was detected at a low ratio in all 4 patients with acute self–limited hepatitis (AH). Wild–type HBV coexisted with mutant HBV in 6 of 7 patients with fulminant hepatitis (FH), and the mean ratio of mutant to total HBV was significantly higher than that in AH. PCR–coupled LCR could be used to detect mutant HBV and to estimate the ratio of mutant to total viruses.
Liver Transplantation in Asian Patients With Chronic Hepatitis B
Authors: Ho Betty M. , So Samuel K. , Esquivel Carlos O. , Keeffe Emment B.
Published: July 2004

It has been suggested that Asian patients have reduced survival after liver transplantation because of greater recurrence of hepatitis B virus (HBV). We analyzed the outcome of Asian and non–Asian patients receiving transplants for chronic hepatitis B between May 1988 and March 1994. Baseline Child–Pugh score and United Network for Organ Sharing (UNOS) status, HBV recurrence, and survival were compared between the two groups. All but one patient received variable doses of hepatitis B immune globulin. Mean follow–up of surviving patients was 28 months (range, 3–71 months). Fifteen Asians and 20 non–Asians underwent transplantation. Six of 15 Asians (40%) and 4 of 20 non–Asians (20%) died during the study period. Although Asians had a lower 1–year survival than non–Asians (59% for Asians and 94% for non–Asians), the 5–year actuarial survival was not different (59% and 57% for Asians and non–Asians, respectively). The causes of death in 5 of 6 Asians were factors other than recurrent hepatitis B, and 4 of 5 deaths occurred within 60 days after transplantation. Eighty percent of Asian patients were Child–Pugh class C at referral, compared with 50% of non–Asians, and Asians were more likely to be status 1 at transplantation (40% vs. 10%;

P

< .05). By contrast, all four deaths in non–Asians occurred late and were secondary to recurrent HBV infection. Of patients surviving more than 60 days after transplantation, 7 of 11 Asians (64%) and 10 of 20 non–Asians (50%) developed recurrent HBV infection (NS). Late mortality attributable to HBV recurrence was lower but not significantly different in Asians (1 of 7 [14%]) than in non–Asians (4 of 10 [40%]). In summary, HBV recurrence and late HBV–related mortality in Asians and non–Asians is similar after liver transplantation for chronic hepatitis B. Late referral and more advanced chronic liver disease at the time of transplantation probably account for the lower 1–year survival of Asians after liver transplantation.
Nucleic Acid Sequence Analysis of the Precore Region of Hepatitis B Virus From Sera of Southern African Black Adult Carriers of the Virus
Authors: Kramvis A. , Bukofzer S. , Kew M. C. , Song E.
Published: July 2004

Our purpose was to ascertain if mutations of the precore region of the hepatitis B virus genome, in particular the 1896 stop codon mutation, are responsible for the 95% hepatitis B e antigen (HBeAg)–negativity rate in southern African black adult carriers. Hepatitis B virus (HBV) DNA was extracted from the serum of 57 asymptomatic carriers (42 HBeAg–negative; 15 HBeAg–positive), the precore region was amplified using the polymerase chain reaction (PCR), and sequenced. Six carriers (14.6%) had mutations known to prevent HBeAg synthesis: 4 involved the precore initiation codon (1814), and one created a stop codon at 1874. The 1896 mutation occurred alone in one carrier only (2.4%). The infrequency of the 1896 mutation can be explained by the high prevalence (70%) of the

adw

subtype in the carriers studied.

Inter alia, adw

differs from

ayw

in that codon 15 is comprised of CCC instead of CCT. The presence of C instead of T in position 1858 precludes the G– to–A mutation at 1896 because the coexistence of these two mutations would destabilize the stem–loop structure of the RNA encapsidation signal, a finding confirmed by our observation that the CCC polymorphism and the 1896 mutation were mutually exclusive. Ten HBeAg–negative carriers (24%) had a missense mutation at position 1862 in the bulge of the RNA encapsidation signal, which may possibly affect HBeAg expression by interfering with either priming of reverse transcription or signal peptide cleavage. We conclude that the 1896 stop codon mutation accounts for a minority only of HBeAg–negative black carriers. A missense mutation in the bulge of the encapsidation signal may contribute to HBeAg negativity.