Disease-associated qualitative and quantitative trait loci in proteoglycan-induced arthritis and collagen-induced arthritis.

Two autoimmune murine models--proteoglycan (aggrecan)-induced arthritis (PGIA) and collagen-induced arthritis (CIA)--were developed in parent strains, F1 and F2 hybrids of major histocompatibility complex (MHC)-matched (H-2) BALB/c x DBA/2 and MHC-unmatched (H-2/H-2) BALB/c x DBA/1 intercrosses. The major goal of this comparative study was to identify disease (model)-specific (PGIA or CIA) and shared clinical and immunologic loci in 2 types of genetic intercrosses. Qualitative (binary/susceptibility) and quantitative (severity and onset) clinical trait loci were separated and analyzed independently or together with various pathophysiologic/immunologic traits, such as antigen-specific T- and B-cell responses and cytokine production. The major quantitative trait locus (QTL) was the MHC on chromosome 17, which was especially dominant in CIA. In addition, chromosomes 3, 5, 10, and X contained shared clinical loci in both models, and a total of 8 QTLs (clinical traits together with immunologic traits) were colocalized in PGIA and CIA.

[Follow-up study of bone mineral density in postmenopausal patients with primary biliary cirrhosis]. / A csont ásványianyag-tartalmának utánkövetéses vizsgálata postmenopausás primer biliaris cirrhosisos nóbetegekben.

Osteopenia is a common complication in primary biliary cirrhosis (PBC). In this follow-up study the authors investigated the metabolic bone disease in postmenopausal PBC patients. 17 Ca and vitamin D supplemented, postmenopausal female patients with PBC (stage II-IV, age: 41-84, mean: 52, each AMA M2 positive, without ascites) were followed-up for an average of 6.3 years. Bone mineral density (BMD) was measured yearly by dual energy x-ray absorptiometry (XR26, Norland) in lumbar spine (L2-4), femoral neck (FN), and radius BMC by single photon absorptiometry. Urinary pyridinoline/creatinine (Pyr/c) and deoxypyridinoline/creatinine ratio (D-Pyr/c) by HPLC, 25-OH-D3 level and standard liver function tests were monitored in all patients. At the beginning the BMD was decreased in 7 out of 17 patients (T-score < -2.5). The mean BMD was 0.885 SD +/- 0.26 g/cm2 in L2-4, 0.725 +/- 0.16 g/cm2 in FN and the BMC 0.703 +/- 0.14 g/cm in the radius. During follow-up the rate of annual bone loss was increased in patients with osteoporosis at the start of this study. There was a correlation between the urinary Pyr/c and D-pyr/c values and the annual rate of bone loss in patients with PBC (r: -0.79; p < 0.01). In patients with severe osteoporosis at the time of the diagnosis of PBC a more pronounced progression of bone loss was observed during the follow-up period.

Relationship between hepatitis C virus recurrence and de novo diabetes after liver transplantation: the Hungarian experience.

De novo diabetes mellitus is a common complication after liver transplantation. It is strongly associated with hepatitis C virus (HCV) infection. We analyzed the relationship between HCV recurrence and de novo diabetes among the Hungarian liver transplant population. This retrospective study included cases from 1995 to 2009 on 310 whole liver transplantations. De novo diabetes was defined if the patient had a fasting plasma glucose ≥126 mg/dL permanently after the third month post liver transplantation, and/or required sustained antidiabetic therapy. De novo diabetes occured in 63 patients (20%). The cumulative patient survival rates at 1, 3, 5, and 8 years were 95%, 91%, 88%, and 88% in the control group, and 87%, 79%, 79%, and 64% in the de novo group, respectively (P=.011). The majority of the patients in the de novo group were HCV positive (66% vs 23%). Early virus recurrence within 5 months was associated with the development of diabetes (80% vs 20% non-diabetic controls; P=.017). The fibrosis (2.05 ± 1.5 vs 1 ± 1; P=.039) and Knodell scores (3.25 ± 2 vs 1.69 ± 1.2; P=.019) were higher among the de novo group after antiviral therapy. Rapid recurrence, more severe viremia, and fibrosis showed significant roles in the developement of de novo diabetes after liver transplantation.

Methene bridge carbon atom elimination in oxidative heme degradation catalyzed by heme oxygenase and NADPH-cytochrome P-450 reductase.

Physiological heme degradation is mediated by the heme oxygenase system consisting of heme oxygenase and NADPH-cytochrome P-450 reductase. Biliverdin IX alpha is formed by elimination of one methene bridge carbon atom as CO. Purified NADPH-cytochrome P-450 reductase alone will also degrade heme but biliverdin is a minor product (15%). The enzymatic mechanisms of heme degradation in the presence and absence of heme oxygenase were compared by analyzing the recovery of 14CO from the degradation of [14C]heme. 14CO recovery from purified NADPH-cytochrome P-450 reductase-catalyzed degradation of [14C]methemalbumin was 15% of the predicted value for one molecule of CO liberated per mole of heme degraded. 14CO2 and [14C]formic acid were formed in amounts (18 and 98%, respectively), suggesting oxidative cleavage of more than one methene bridge per heme degraded, similar to heme degradation by hydrogen peroxide. The reaction was strongly inhibited by catalase, but superoxide dismutase had no effect. [14C]Heme degradation by the reconstituted heme oxygenase system yielded 33% 14CO. Near-stoichiometric recovery of 14CO was achieved after addition of catalase to eliminate side reactions. Near-quantitative recovery of 14CO was also achieved using spleen microsomal preparations. Heme degradation by purified NADPH-cytochrome P-450 reductase appeared to be mediated by hydrogen peroxide. The major products were not bile pigments, and only small amounts of CO were formed. The presence of heme oxygenase, and possibly an intact membrane structure, were essential for efficient heme degradation to bile pigments, possibly by protecting the heme from indiscriminate attack by active oxygen species.

Effects of gestational exposure to Tordon 202c on fetal growth and development in CD-1 mice.

The teratogenic effects of Tordon 202c, a picloram and 2,4-D combination formulation, are unknown. Pregnant CD-1 mice were exposed to Tordon 202c in the drinking water at concentrations of 0.10, 0.21, and 0.42% from d 6 to 15 of gestation. Fetal growth parameters, including body weight and crown-rump length, were reduced in a dose-dependent manner, as was placental weight. The incidence of dead fetuses/resorptions and malformed fetuses (especially cleft palate) was increased in the highest dosage group. A subtle indication of maternal toxicity was noted in the highest dosage group as evidenced by decreased water consumption and increased relative liver weight. The present study suggests that Tordon 202c is embryotoxic and teratogenic in CD-1 mice when administered during organogenesis.

Effects of paternal subacute exposure to Tordon 202c on fetal growth and development in CD-1 mice.

Male CD-1 mice were exposed to Tordon 202c (a picloram and 2,4-D combination herbicide) in the drinking water at concentrations of 0.21, 0.42, and 0.84% solutions for 60 days prior to mating with untreated females. Subsequently there was no exposure to Tordon 202c during gestation. Fetal weight and crown-rump length were reduced in the highest dosage group. The incidence of malformed fetuses (e.g., ablepharon, cleft palate, and unilateral agenesis of the testes) was increased in the middle dosage group while the incidence of fetuses with variants was increased in the lowest (e.g., an extra pair of ribs) and the highest dosage groups (e.g., incomplete ossification of the skeleton). The frequency of pregnancy failure was increased in the middle dosage group. Indices of paternal toxicity included increased lethality and decreased water consumption in the highest dosage group and increased relative spleen weights in the lowest and middle dosage groups. The results suggest paternally mediated reproductive toxicity.

Effects of preconceptional and gestational exposure to Tordon 202c on fetal growth and development in CD-1 mice.

Female CD-1 mice were exposed to Tordon 202c (a picloram and 2,4-D combination herbicide) in the drinking water at concentrations of 0.21, 0.42, and 0.84% for 60 days prior to mating with untreated males. One-half of the pregnant females subsequently continued treatment throughout gestation while the remaining females were maintained on distilled water. Fetal weight, crown-rump length, placental weight, and maternal gestational weight gain were reduced in a dose-dependent manner following combined preconceptional and gestational exposure. The incidence of malformed fetuses (cleft palate, renal agenesis, hydronephrosis, unilateral testicular agenesis, and umbilical hernia) and fetuses with variants (especially incomplete ossification of the skeleton) were increased in a dose-dependent manner following combined exposure. Increased maternal mortality and decreased preconception weight gain were observed in the highest-dosage group. Relative maternal liver weight was increased in a dose-dependent manner. The results suggest that combined preconceptional and gestational exposure to Tordon 202c is required for teratogenesis and fetal growth depression. Preconceptional exposure alone is not effective in increasing the risk for embryotoxicity.

Serum dipeptidyl peptidase IV (DPP IV, CD26) activity in chronic hepatitis C.

BACKGROUND: DPP IV is a cell surface ectoenzyme widely distributed in the human body. It has been implicated in T-cell activation, hepatocyte-extracellular-matrix interactions and fibroblast proliferation. Furthermore, upregulated CD26 expression has been found on the surface of human hepatoma cells transfected with hepatitis C virus (HCV) c-DNA. We examined the serum DPP IV activity in a large number of patients with chronic HCV infection in a cross-sectional study. We also investigated whether the activity differs from that in controls and depends upon the response to interferon (IFN) therapy. METHODS: Serum DPP IV activity was measured by microplate-based (Multiskan-Plus-MKII, Labsystem) kinetic assay in 144 patients with chronic HCV infection. Seventy-four out of 144 patients (46 non-responders, 28 responders) were formerly treated with interferon. Sixty healthy blood donors served as controls. Gly-Pro-PNA (Bachem, Torrance, USA) was used as substrate. Results are expressed in nmol/ml/min (U/l). Shapiro-Wilk's test, Mann-Whitney U test and Spearman rank order correlation were used for statistical analysis. RESULTS: Serum DPP IV activity was significantly higher (mean = 20.89 [s 9.6]) in patients with chronic HCV infection than in healthy controls (12.39 [2.76, P < 10(-5)]). The enzyme activities significantly differed in naive HCV-positive patients (22.2 [9.89, P < 10(-5)]) and non-responders (23.28 [9.57, P < 10(-5)]) from that in the healthy controls and also from that in responders (13.69 [4.21]). Correlation was found between DPP IV activity and AST (r = 0.44, P < 10(-5)), ALT (r = 0.44, P < 10(-5)), GGT (r = 0.41, P < 10(-5)) levels. CONCLUSION: Serum DPP IV activity seems to be an indicator of HCV induced liver injury. The activity may reflect the efficacy of interferon therapy.

Effect of cholestasis produced by bile duct ligation on hepatic heme and hemoprotein metabolism in rats.

Cholestasis produced by bile duct ligation has been associated with decreased concentrations of hepatic microsomal cytochrome P450 and decreased hepatic microsomal oxidative drug metabolism. Bile duct ligation producing cholestasis results in a marked increase in hepatic microsomal heme oxygenase activity, with corresponding decreases in hepatic microsomal cytochrome P450 concentration, reduced form of nicotinamide adenine dinucleotide phosphate-cytochrome c reductase activity, and hepatic delta-aminolevulinic acid synthetase activity. As sham-operated rats also demonstrate a less prolonged decrease in cytochrome P450 concentration and reduced form of nicotinamide adenine dinucleotide phosphate-cytochrome c reductase activity, the metabolic effects of surgery and anesthesia must also be involved in these alterations in microsomal oxidative drug metabolism. The relative rate of hepatic cytochrome P450 synthesis and of degradation are both decreased after bile duct ligation. These data suggest that decreased hepatic microsomal cytochrome P450 concentrations in cholestasis are partly the result of decreased cytochrome P450 synthesis. Increased levels of heme oxygenase activity are not related to increased cytochrome P450 turnover, but may instead reflect enlargement and increased catabolism of a free heme pool resulting from decreased hemoprotein (cytochrome P450) synthesis.

Hypersomnia in Wilson's disease: an unusual symptom in an unusual case.

Wilson's disease (WD) shows a wide heterogeneity in symptoms. In this case report we present hypersomnia as a symptom of WD. The male patient's complaints as fatigue, decreased level of concentration, and highly increased demand of sleeping started at his age of 21 years. No abnormality was found at physical examination. A moderate elevation in liver function tests was found, but all the other laboratory findings were within the normal range. The marked hypersomnia was verified by 24-h cassette EEG polisomnographic monitoring. No abnormality was found at physical examination. EEG, brain CT and MRI were normal. Neither toxic nor infectious disease was detectable. The diagnosis of WD was based on decreased coeruloplasmin level, increased baseline and forced urinary excretion of copper, and decreased level of serum copper. Kayser-Fleischer ring was not detectable. D-penicillamine (DPA) was introduced. At 8-10 months after the initiation of the therapy the patient's complaints gradually resolved. The control sleep record 14 months after the initiation of the DPA therapy was normal. Five years later the patient is currently on penicillamine treatment and he is free of any symptom.

Mechanism of action of heme oxygenase. A study of heme degradation to bile pigment by 18O labeling.

The formation of bile pigment from heme by a reconstituted heme oxygenase system containing purified bovine spleen heme oxygenase, NADPH-cytochrome P-450 reductase, and biliverdin reductase was studied under an atmosphere containing 18,18O2. The product, bilirubin, was isolated and subjected to mass spectrometry, which revealed incorporation of 18O consistent with a two-molecule mechanism, whereby the product bile pigment contains oxygen atoms derived from two different oxygen molecules.

Elevated serum dipeptidyl peptidase IV (CD26, EC 3.4.14.5) activity in experimental liver cirrhosis.

BACKGROUND: Dipeptidyl peptidase IV (DPP IV) is a cell surface ectoenzyme widely distributed in the rat body, present on the epithelial cells of the brush border membranes (e.g. bile canaliculi) and on the surface of reactive lymphocytes and fibroblasts. DPP IV has been implicated in hepatocyte-extracellular matrix interactions, fibroblast activation and proliferation and in T-cell activation. Aberrant DPP IV expression was found in human liver cirrhosis, and elevated serum DPP IV activity was reported in patients with primary biliary cirrhosis and chronic hepatitis C virus infection. The aim of the study was to examine serum DPP IV activity in experimental liver cirrhosis. METHODS: Liver cirrhosis was induced by administering diethyl-nitrosamine, phenobarbital and CCl4 in Fischer-344 male rats (n = 22). Phenobarbital-treated (n = 9) and nontreated (n = 9) male rats were used as controls. Serum DPP IV activity was measured using a microplate-based continuous-monitoring assay. Recombinant rat DPP IV was used as standard and Gly-Pro-PNA was used as substrate. Enzyme activity was given in nmol mL-1 min-1 (U L-1). RESULTS: Significantly higher DPP IV activity was found in the sera of rats with experimental liver cirrhosis (39.2 +/- 3.7; mean +/- SD) compared to phenobarbital-treated (11 +/- 4, P < 0.000002) and nontreated (10.9 +/- 0.9, P < 0.000002) rats. There was a positive correlation between DPP IV activity and concentrations of aspartate aminotransferase (r = 0.73, P = 0.0001) and alanine aminotransferase (r = 0.69, P = 0.0004). CONCLUSIONS: The significantly higher serum DPP IV activity found in experimental liver cirrhosis is in concordance with human observations. The elevation was probably not due to the enzyme induction effect of phenobarbital. In this experimental model, serum DPP IV seems to be an indicator for chronic liver injury.

Localization of hepatitis C virus RNA on human erythrocytes by RT in situ PCR technique.

BACKGROUND: Our previous results showed that hepatitis C virus (HCV) is detectable on erythrocytes by RT in situ PCR. The aims of the present study were to compare the sensitivity of this erythrocyte in situ PCR to routine serum solution phase HCV PCR as well as to obtain more data about the binding and cellular localization of HCV in the erythrocyte. METHODS: 105 previously HCV-infected patients and 20 control individuals were studied using RT in situ PCR on erythrocytes and solution phase RT-PCR from serum samples. Binding of HCV to erythrocytes was studied by in vitro inoculation. RT in situ PCR results were evaluated by fluorescence and confocal laser scanning microscopy. RESULTS: From 105 HCV cases, 78 gave positive, while 5-and all control cases-gave negative results by both PCR techniques. In 21 cases, only the in situ technique provided positive results, while in only I case did the solution phase method provide positive results. During in vitro inoculation, an early HCV-erythrocyte binding was detected followed by virus internalization. CONCLUSIONS: Erythrocyte-in situ PCR was found to show higher sensitivity for the detection of HCV compared to the generally applied serum PCR method. In vitro studies suggested a specific binding of HCV to erythrocyte and showed the virus to be capable of internalization.