Long-term outcome of chronic type B hepatitis in patients who acquire hepatitis B virus infection in childhood

Seventy-six children aged 1-13 years who were known to be positive for hepatitis B surface antigen and hepatitis B e antigen in serum for at least 6 months and who had biopsy-proven chronic hepatitis have been followed longitudinally for 1-12 years (mean, 5 years). Twenty-three of them are now young adults. Eight patients had acute type B hepatitis 12-24 months before entering the study, while 68 patients came to observation during a chronic phase. At the beginning of follow-up, all 76 children were positive in serum for hepatitis B virus DNA, and 44 (58%) had chronic active hepatitis, associated with cirrhosis in two cases. During follow-up, 23 (30%) patients remained hepatitis B e antigen-positive, most with unchanged biochemical and histological features. The other 53 (70%) cases seroconverted to hepatitis B e antibody and cleared hepatitis B virus DNA from serum, including 7 of 8 (87%) patients with acute hepatitis at presentation. After seroconversion, alanine aminotransferase levels normalized in all patients and remained normal in 49 patients (92.5%) throughout a mean observation period of 3 years. Five of these children, including 2 of 7 (29%) with previous acute hepatitis, eventually cleared hepatitis B surface antigen from their sera. Finally, 4 (7.5%) patients experienced a mild increase of alanine aminotransferase levels several months after seroconversion in the absence of hepatitis B virus replication or of delta virus superinfection. Clinical and virological parameters did not significantly differ between patients with or without acute onset; however, seroconversion occurred earlier, and the rate of hepatitis B surface antigen clearance was greater in the former than in the latter group. The present data indicate that approximately two thirds of children with hepatitis B e antigen- and hepatitis B virus DNA-positive chronic hepatitis clear hepatitis B virus DNA from their sera before reaching adulthood. After termination of viral replication, most patients achieve a sustained biochemical remission, suggesting the disappearance of disease activity. Reactivation of virus replication after hepatitis B e antibody seroconversion has never been observed in this series, although mild alanine aminotransferase level abnormalities could be detected in a minority of cases.

Chronic hepatitis C in children: the pathological and clinical spectrum

BACKGROUND & AIMS

Apart from the high-risk groups, the pathology of chronic hepatitis C in children is not well known. The aim of this study was to investigate the morphology of chronic hepatitis C in children without any underlying systemic disease and to evaluate its relationship to clinicovirological factors.

METHODS

Liver biopsy specimens from 80 children positive for antibody to hepatitis C virus were evaluated using a semiquantitative scoring system.

RESULTS

Chronic hepatitis was mild in most cases but had high-grade activity in 17 children (21.2%). A significant association was found between the grade of focal necrosis and alanine transaminase levels (P < 0.003). Fibrosis was absent in 22 cases (27.5%), mild in 44 (55%), and moderate in 13 (16.2%). Only 1 patient had cirrhosis. A significant relationship was detected between fibrosis scores and (1) duration of disease (P < 0.03); (2) portal inflammation (P < 0. 002); and (3) interface hepatitis (P < 0.003).

CONCLUSIONS

In otherwise healthy children, chronic hepatitis C is a morphologically mild disease in most cases. Fibrosis increases with the duration of disease, suggesting that end-stage disease may develop in young adulthood. Alanine transaminase levels correlate with intralobular focal necrosis but not with other lesions. In this respect, liver biopsy retains its importance in the management of chronic hepatitis C in children.

Carbohydrate-deficient transferrin (CDT) as a marker of alcohol abuse: a critical review of the literature 2001-2005

The diagnosis of alcohol abuse based on objective data is a necessary requirement in both clinical and forensic environments. Among the different biomarkers of chronic alcohol abuse, carbohydrate-deficient transferrin (CDT) is world wide recognized as the most reliable indicator. However, several problems about the real meaning of CDT and the reliability of its use for the diagnosis of alcohol abuses are still open, as reported by numerous research articles and reviews. The present article presents a critical review of the literature on CDT appeared in the period from 2001 to 2005 (included). The article is organized in the following sections: (1) introduction, (2) definition and structure of human serum CDT, (3) pathomechanisms of the ethanol-induced CDT increase, (4) preanalysis, (5) analysis, (6) data interpretation, (7) review papers, (8) conclusions. As many as 127 papers appeared in the international literature and retrieved by the search engines PubMed and Scopus are quoted.

Outcome of chronic hepatitis B in Caucasian children during a 20-year observation period

BACKGROUND/AIMS

Chronic hepatitis B virus infection can lead to cirrhosis and hepatocellular carcinoma, particularly in men over 40 years of age and in areas where childhood-onset infection is common. The sequence of events from paediatric infection to severe disease in adults is only partially known. The aim of this study was to evaluate the evolution of chronic hepatitis B acquired in childhood during 20 years of follow-up.

PATIENTS

One hundred and eighty-five consecutive, otherwise healthy, Caucasian children were enrolled in Padua (Italy) and in Madrid (Spain) between 1975 and 1985, and followed for an average period of 13 years; 168 were hepatitis B e antigen (HBeAg) positive and five had cirrhosis.

RESULTS

Thirty patients received steroids or levamisole and 21 interferon, but treatment did not significantly influence HBeAg clearance. Overall, two (1.1%) children, with initial cirrhosis, developed hepatocellular carcinoma and the other three (1.6%) cirrhotic patients became asymptomatic carriers of infection after anti-HBe seroconversion and biochemical remission; 14 (7.5%) children maintained HBeAg positive hepatitis; 155 (83.8%) became asymptomatic carriers of infection after anti-HBe seroconversion and biochemical remission; six (3.2%) experienced reactivation of liver disease and viral replication after remission and five (2.7%) maintained biochemical features of liver damage after HBeAg clearance. Only 6% cleared hepatitis B surface antigen.

CONCLUSIONS

Even considering the bias of treatment, the large majority of Caucasian children with chronic hepatitis B became asymptomatic carriers of infection with normal alanine amino-transferase during the first 20 years of observation. Cirrhosis is an early, rare complication, and a risk factor for hepatocellular carcinoma. A subgroup of patients who experienced reactivation or maintained liver damage after HBeAg clearance seems to be at greater risk for disease progression during adult life.

Liver cirrhosis associated with chronic hepatitis B virus infection in childhood

We evaluated the prevalence and the clinical features of liver cirrhosis associated with chronic hepatitis B virus (HBV) infection in a prospective study of 292 consecutive children who were chronic HBsAg carriers with increased aminotransferase activity. Liver histologic changes at presentation were consistent with cirrhosis in 10 (3.4%) patients (100% boys, mean age 4.0 +/- 3.3 years). In none of the remaining children, including 166 with histologic evidence of chronic active hepatitis, did the condition progress to cirrhosis during an observation period of 1 to 10 years. This lack of progression suggests that cirrhosis is an early complication of chronic HBV disease in some patients. A higher prevalence of delta infection and increased incidence of blood transfusions were observed in patients with cirrhosis, supporting the hypothesis that superinfection with delta or non-A, non-B agents may play a synergistic role. Eight of 10 patients had histologic features of disease activity at presentation, although only two had symptoms. During follow-up, persistence of disease activity was observed only in the three delta antigen-positive patients. None of the patients with inactive cirrhosis have developed signs of liver failure or portal hypertension.

Posttransfusion and community-acquired hepatitis C in childhood

Following a longitudinal study of chronic non-A, non-B hepatitis in Italy and Spain, we evaluated the epidemiologic and clinical features of chronic hepatitis C in 77 consecutively observed children (35 male; mean age, 4 years) without underlying systemic diseases. All subjects were positive for antibody to hepatitis C virus in serum by second-generation tests. Forty-six patients had received blood transfusions in the perinatal period; 12 had a mother with antibodies to HCV in serum (five of these mothers were drug users or partners of a drug user); seven had a history of putative percutaneous exposure; and 12 had not been exposed to any risk factors for viral hepatitis. At presentation, only 22% were symptomatic, mean alanine-aminotransferase levels were three times the upper normal value, and liver histology showed active disease in only nine of 28 cases (32%). During a mean observation period of 6 years, only 11 of 57 patients (19%) complained of symptoms and 11 of 40 cases (27%) had histologic features of active hepatitis. Two patients had severe hepatitis with associated cirrhosis. However, only six of 57 cases (10%) achieved sustained biochemical remission. The clinical features and the outcome were similar in both the posttransfusion and the community-acquired cases. These results indicate that transfusions in the perinatal period are the single most important cause of hepatitis C in otherwise healthy children. Community-acquired cases represent an heterogeneous epidemiologic group in which maternal transmission, whether perinatal or postnatal, could be relevant.(ABSTRACT TRUNCATED AT 250 WORDS)

Long term effect of alpha interferon in children with chronic hepatitis B

BACKGROUND/AIMS

The purpose of this study was to better define the long term prognosis of infection and disease in children with chronic hepatitis B treated with interferon (IFN) alpha.

PATIENTS

A total of 107 children with chronic hepatitis B who received IFN alpha for three or six months in two clinical trials were followed for a mean period of 69 (17) months. Response to treatment was defined as loss of hepatitis B e antigen (HBeAg) within 12 months after stopping treatment. A control group of 59 patients was also followed for a shorter mean time (46 (19) months).

RESULTS

Sixteen (15%) treated children responded during therapy and 18 (17%) during post-treatment follow up; 31 (29%) non-responders lost HBeAg during subsequent years. High pretreatment levels of transaminases and a greater histological activity index were predictors of response. Kaplan-Meier estimates of cumulative HBeAg clearance rates at five years were similar between treated patients (60%) and controls (65%). After HBeAg clearance, all cases lost hepatitis B virus DNA and 94% had normal transaminase levels. Loss of hepatitis B surface antigen (HBsAg) occurred in four (25%) patients who responded during treatment but in none of the other treated or untreated patients.

CONCLUSIONS

After five years' observation, the proportion of treated children with sustained HBeAg clearance comprised an equal number of responders and non-responders and did not differ from that observed in untreated controls, suggesting that IFN simply accelerated a spontaneous event. However, IFN significantly improved the rate of HBsAg loss in cases with more prominent disease activity who were early responders, and may be particularly useful in this type of patient.

Non-organ specific autoantibodies in children with chronic hepatitis C

BACKGROUND/AIMS

Recent studies in adult patients have established a relationship between hepatitis C virus infection and the presence of liver-kidney microsomal autoantibody type 1 (LKM1). Conversely, little is known regarding the relationship between hepatitis C and autoimmunity in children. In this study, we investigated non-organ specific autoantibodies in 40 otherwise healthy Italian children with chronic hepatitis C.

METHODS

All but four patients included in the study were asymptomatic. Liver histology, obtained in 35, showed features ranging from minimal to mild chronic hepatitis. Autoantibodies were investigated by indirect immunofluorescence. HCV RNA was assayed by the polymerase chain reaction in 34 cases and viral genotypes were determined.

RESULTS

Antinuclear antibodies were detected in three (7.5%) cases, one with a homogeneous pattern; smooth muscle autoantibodies in seven (17.5%) cases, always with V (vessels only) specificity and LKM1 in four (10%), at titers ranging from 1:20 and 1:2560. Clinical and virologic features did not significantly differ between autoantibody positive and negative cases, although infections with HCV genotypes 1a and 2 were more frequent in LKM1-positive patients. During observation, the child with the highest LKM1 titre was unsuccessfully treated with alpha interferon but responded to steroids. Twelve LKM1 negative children were also treated with interferon and one developed low LKM1 titers concomitant with an alanine aminotransferase flare. The sera of the five LKM1-positive children with investigated by immunoblotting with a human microsomal fraction and peptide 257-269 of cytochrome P450IID6. Only the serum of the child with the highest LKM1 titers was reactive.

CONCLUSIONS

These results show that a consistent proportion of children with chronic hepatitis C circulate non-organ specific autoantibodies. The prevalence of LKM1 is greater than in adults and this could raise problems for the treatment of the disease with interferon. The analysis of LKM1 target antigens might help to identify putative cases of "true" autoimmune hepatitis with concomitant HCV infection that could benefit from steroid treatment.

Prenatal development of glucocorticoid receptor gene expression and immunoreactivity in the rat brain and pituitary gland: a combined in situ hybridization and immunocytochemical analysis

By means of in situ hybridization and immunocytochemical techniques it has been possible to follow the prenatal development of glucocorticoid receptor (GR) messenger RNA (mRNA) expression and GR immunoreactivity (IR) in the rat brain from embryonic day (E) 15 to 22. A 700-base-pair GR cDNA fragment was used for RNA probe generation. In the immunocytochemical analysis a mouse monoclonal antibody (IgG2a) against the rat liver GR was used in combination with the indirect fluorescence technique or the avidin-biotin immunoperoxidase method. At E15 till E22 a moderate to strong GR mRNA signal was observed within the neuro-epithelium from the medulla oblongata to the telencephalon. A moderate to strong labelling was also present within the paraventricular hypothalamic nucleus, the arcuate nucleus, the nucleus raphe magnus, the nucleus raphe obscurus and the locus coeruleus. In these areas a weak to moderate nuclear GR IR developed in nerve cells 1 or 2 days after the appearance of the GR mRNA signal. From E15 the adenohypophysis showed the strongest expression of GR mRNA. At E17 a strong GR IR was especially demonstrated in the nuclei of many pituitary cells, some exhibiting adrenocorticotropin IR. The results open up the possibility that there exist active GR in embryonic life capable of regulating proliferation events within the adenohypophysis and the neuro-epithelia of the brain. This embryonic GR may modulate the development of inter alia neuro-endocrine areas such as the paraventricular and arcuate nuclei and arousal-related areas such as the central 5-hydroxytryptamine and noradrenaline neuronal systems. Provided that this embryonic GR is capable of becoming activated by glucocorticoids in fetal life, it may mediate several neurochemical and behavioural impairments caused by prenatal stress.

Basic FGF is present in dopaminergic neurons of the ventral midbrain of the rat

Immunocytochemistry procedures and 6-hydroxy-dopamine-induced degeneration of dopamine nerve cells provided evidence that practically all tyrosine hydroxylase immunoreactive (IR) neurons of the substantia nigra and ventral tegmental area contain cytoplasmic basic fibroblast growth factor immunoreactivity (bFGF IR), while many astroglial cells in the neostriatum and substantia nigra contain nuclear bFGF IR. RNA blot analysis demonstrated strong expression of a major 3.7 kb bFGF mRNA in the substantia nigra and ventral tegmental area. These results indicate that bFGF may be a significant growth factor in the DA neurons.

Hepatitis C virus infection and related liver disease in children of mothers with antibodies to the virus

OBJECTIVE

To evaluate the clinical, biochemical, and virologic features associated with hepatitis C virus (HCV) infection acquired early in life from mothers with antibodies to HCV (anti-HCV).

STUDY DESIGN

Multicenter prospective-retrospective study in Italian children.

PATIENTS

Two groups of children were investigated. Group 1 included 14 infants, born to mothers with anti-HCV but without human immunodeficiency virus infection, who became seropositive for HCV RNA during the first year of life and were thus considered infected. Group 2 included 16 children with chronic hepatitis C, aged 1 1/2 to 14 years, whose mothers were the unique potential source of infection. Both groups were followed for 12 to 48 months.

METHODS

Alanine transaminase (ALT), anti-HCV, and HCV RNA were investigated by the polymerase chain reaction on entry to the study and during follow-up.

RESULTS

All children in group 1 had anti-HCV throughout follow-up, and all had ALT abnormalities, ranging from 1.5 to 10.5 times the normal value during the first 12 months. During further follow-up, 5 of 10 children had HCV RNA with abnormal ALT values, 3 had a return to normal of the ALT values but continued to have viremia, and 2 eventually had normal ALT values and clearance of HCV RNA. Of the 16 children in group 2, all were free of symptoms and 62% had only slight ALT elevations; 7 who underwent liver biopsy had histologic features of minimal or moderate hepatitis.

CONCLUSIONS

HCV infection acquired early in life from mothers with anti-HCV is usually associated with biochemical features of liver damage during the first 12 months of life. Progression to chronicity seems to occur in the majority of cases, although HCV-associated liver disease is likely to be mild throughout infancy and childhood.

Interferon-alpha treatment of chronic hepatitis B in childhood: a consensus advice based on experience in European children

BACKGROUND

The efficacy of interferon (IFN) in children with chronic hepatitis B has been evaluated in randomized controlled trials over the past decade, but recommendations for treatment based on this experience have not been published yet. The purpose of this workshop, held in Madrid in October 1997, was to provide pediatricians with guidelines for practical use of IFN in hepatitis B.

METHODS

Eighteen European pediatricians and hepatologists agreed to report and discuss their experience on 1,122 treated children, 40% of whom were considered responders.

RESULTS

Agreement was obtained on the following main items: 1) rationale for treatment is to accelerate hepatitis B early antigen (HBeAg) clearance in a subgroup of patients; 2) candidates for treatment are children with HBeAg and HBV DNA positivity, with low-intermediate HBV DNA levels and abnormal alanine aminotransferase values, aged 2 years or more; 3) IFN is contraindicated in children with decompensated liver disease, cytopenia, severe renal or cardiac disorders, and autoimmune disease; 4) the standard treatment regimen is 5 mU/m2 thrice weekly for 6 months. Retreatment in nonresponders is not indicated.

CONCLUSIONS

A consensus was obtained on the use of IFN in children with hepatitis B, based on its short-term efficacy. The long-term clinical and virological effects of the drug, however, remain to be evaluated.

Changing epidemiologic pattern of chronic hepatitis C virus infection in Italian children

OBJECTIVE

To evaluate the epidemiologic features of chronic hepatitis C virus (HCV) infection in children.

STUDY DESIGN

All 106 children with chronic HCV infection consecutively observed in 3 Italian pediatric centers between 1991 and 1997 entered the study.

RESULTS

Fifteen children had a history of non-A, non-B hepatitis, and 5 complained of nonspecific symptoms. The 86 remaining patients were free of symptoms and were recruited after HCV screening for intercurrent diseases, maternal infection, or other putative exposure; 39% (none of 30 children born after 1990) had received transfusions, whereas 44%, had a mother with HCV infection. Of the 47 infected mothers, 36% were or had been intravenous drug users, 15% had received transfusions, and 45% had no history of exposure.

CONCLUSIONS

Children with chronic HCV infection are often free of symptoms, and thus HCV screening for putative risk has greatly increased the chances of diagnosis. Vertical transmission seems to now be the most common route of infection. Both current and past maternal intravenous drug abuse are risk factors for pediatric infection; however, in an area with relatively high prevalence of anti-HCV in the general population such as Italy, a consistent proportion of infectious mothers have no risk factors of HCV exposure.

T-lymphocyte cytotoxicity to HBsAg-coated target cells in hepatitis b virus infection

The cytotoxic effect of peripheral lymphocytes on chicken red blood cells (ChRBC) coated with purified hepatitis B surface antigen (HBsAg) has been studied as an in vitro parameter of cell-mediated immunity in acute and chronic infection with hepatitis B virus. Using this technique, the mean cytotoxic index of lymphocytes from patients with acute hepatitis B (29.13 +/- 20.88) was significantly higher than that obtained with lymphocytes from control subjects (6.53 +/- 3.75). Only 33.3% of the patients with HBsAg-positive chronic active hepatitis exhibited lymphocyte cytotoxicity to HBsAg-coated target cells and the mean cytotoxic index (11.66 +/- 6.60) was in these cases significantly lower than that found in acute hepatitis B. Healthy chronic carriers of HBsAg failed to show lymphocyte cytotoxicity to target cells. The effector cells detected in acute hepatitis B by this in vitro assay have been demonstrated to be T-lymphocytes, as T-cell depleted subpopulations lacked cytotoxic activity. Target cell lysis could be blocked by addition of HBsAg-coated unlabelled ChRBC as well as of purified HBsAg in the culture tubes. It is suggested that damage to the liver cells in acute hepatitis B is related to the presence of cytotoxic T-lymphocytes reacting with HBsAg on the surface of infected hepatocytes. An inadequate lymphocyte response to the antigen may be responsible for the persistence of the infection in the liver with varied clinical manifestations and associated hepatic lesions.

Hair analysis for illicit drugs by using capillary zone electrophoresis-electrospray ionization-ion trap mass spectrometry

In forensic toxicology, hair analysis has become a well established analytical strategy to investigate retrospectively drug abuse histories. In this field, gas chromatography-mass spectrometry and high-performance liquid chromatography-mass spectrometry are currently used, often after preliminary screening with immunoassays. However, on the basis of previous applications to pharmaceutical analysis, capillary zone electrophoresis coupled to ion trap mass spectrometry looks also highly promising. The purpose of the present work was the development of a simple and rapid CZE-MS method for sensitive and quantitative determination of the main drugs of abuse and their metabolites (namely, 6-monoacetylmorphine, morphine, amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethampthetamine (MDMA), benzoylecgonine, ephedrine and cocaine) in human hair. Hair samples (100 mg) were washed, cut and incubated overnight in 0.1 M HCl at 45 degrees C, then neutralized with NaOH and extracted by a liquid-liquid extraction method. CZE separations were carried out in a 100 cm x 75 microm (I.D.) uncoated fused silica capillary. The separation buffer was composed of 25 mM ammonium formate, pH 9.5; the separation voltage was 15 kV. Electrokinetic injections were performed at 7 kV for 30 s under field amplified sample stacking conditions. ESI-ion trap MS detection was performed in the ESI positive ionization mode using the following conditions: capillary voltage 4 kV, nebulizer gas (nitrogen) pressure 3psi, source temperature 150 degrees C and drying gas (nitrogen) flow rate 8l/min. A sheath liquid, composed of isopropanol-water (50:50, v/v) with 0.5% formic acid, was delivered at a flow rate of 4 microl/min. The ion trap MS operated in a selected ion monitoring mode (SIM) of positive molecular ions for each drug/metabolite. Collision induced fragmentation was also possible. Nalorphine was used as internal standard. Under the described conditions, the separation of all compounds, except amphetamine/methamphetamine, MDA/MDMA and morphine/6-MAM was achieved in 20 min, with limits of detection lower than the most severe cut-offs adopted in hair analysis (i.e. 0.1 ng/mg). Linearity was assessed within drug concentration ranges from 0.025 to 5 ng of each analyte/mg of hair. Analytical precision was fairly acceptable with RSD's < or = 3.06% for migration times and < or = 22.47% for areas in real samples, in both intra-day and day-to-day experiments. On these grounds, the described method can be proposed for rapid, selective and accurate toxicological hair analysis for both clinical and forensic purposes.

Recombinant interferon-alfa therapy in children with chronic hepatitis C

The efficacy of recombinant interferon-alfa therapy in children with chronic hepatitis C has been evaluated in a randomized, controlled pilot study including 27 patients, aged 2 to 14 years, without underlying systemic diseases. On entry, all patients had abnormal alanine transaminase (ALT) levels, 22 were hepatitis C virus (HCV) RNA positive, 19 had mild chronic active hepatitis, and 8 had chronic persistent hepatitis on liver biopsy. Fourteen children received 5 MU/m2 of recombinant interferon-alfa2b thrice weekly for 4 months. If at this time ALT had been reduced to at least 50% the baseline level, treatment was continued up to 12 months. The other 13 children remained untreated. The whole follow-up period lasted 24 months. Interferon was stopped at 4 months in 4 children because of an ALT increase (2 cases), unchanged ALT and febrile convulsions (1 case), and slight ALT decrease (1 case). This latter patient, however, had normal ALT at 6 months and throughout further follow-up, and cleared HCV RNA, thus behaving as a sustained responder. All 10 children treated for 12 months had normal levels of ALT, and 9 were HCV RNA negative at the end of treatment. Of the 9 children who could be followed to 24 months, 4 relapsed soon after therapy withdrawal and 5 maintained a sustained biochemical and virologic response. Overall, 6 (43%) of 14 treated children had a sustained ALT normalization associated with HCV RNA clearance as compared with only 1 (7.5%) untreated child who had a sustained ALT normalization but did not clear HCV RNA.(ABSTRACT TRUNCATED AT 250 WORDS)

Molecular mechanism involved in the transport of a prodrug dopamine glycosyl conjugate

We have previously demonstrated that dopamine conjugation to glucose allows it to induce therapeutic effects against Parkinson's disease after intravenous administration. In this paper we demonstrate that, unlike dopamine, the prodrug glu-dopamine is a transportable substrate of glucose transporters. Towards this, the effect of glucose-conjugation on the affinity and uptake of dopamine have been assessed in vitro, using human retinal pigment epithelium (HRPE) cells. Glucose transporter-mediated uptake was measured using [(3)H]3-O-methylglucose ([(3)H]3-O-MG) as the tracer. The uptake was found to be rapid and hyperbolically related to its concentrations (K(t)=7.8+/-1.2mM and V(max)=54+/-2 nmol/min mg protein). Inhibition experiments showed that dopamine was able to interact with glucose carriers only when conjugated to glucose (IC(50)=2.6+/-0.6mM). HPLC analysis of HRPE cell extracts showed that both dopamine and the prodrug permeate the cell, but only the uptake of the prodrug is inhibitable by glucose. This confirms that glucose transporters mediate the transport of the prodrug glu-dopamine, but not of dopamine. HRPE cells is therefore proposed as a promising model for in vitro studies involving the glucose transporter-mediated transport of drugs and their conjugates.

Lymphoblastoid interferon alfa with or without steroid pretreatment in children with chronic hepatitis B: a multicenter controlled trial

The comparative efficacy of prednisolone followed by interferon alfa (IFN-alpha) versus IFN-alpha alone in enhancing the rate of antibody to hepatitis B e antigen (anti-HBe) seroconversion has not been evaluated in a large cohort of white children. To determine this, a multicenter-controlled trial was conducted in 95 hepatitis B virus (HBV)-DNA/hepatitis B e antigen (HBeAg)-positive children (median age, 9 years [range, 2-16 years]; 56 boys; 84 [89 percent] white), all having inflammatory changes on liver biopsy. Patients were randomized to receive either prednisolone followed by IFN-alpha (n = 34); placebo followed by IFN-alpha (n = 30); or no treatment (n = 31). The prednisolone/placebo was given on a double-blind basis. Lymphoblastoid IFN-alpha was given at 5 MU/m(2) three times a week for 12 weeks. Baseline clinical, biochemical, and histological features were similar for the three groups. The majority (85 percent) had a baseline aspartate aminotransferase (AST) level < or = 100 IU/L. On follow-up between 12 and 18 months (median, 15 months) after treatment, the loss of HBeAg with anti-HBe seroconversion was more common in patients pretreated with steroids (12 of 34 [35 percent]) or placebo [12 of 30 (40 percent)] as against controls (4 of 31 [13 percent], P< .05). Factors predictive of anti-HBe seroconversion were baseline HBV-DNA concentration of < or = 1,000 pg/mL and a greater degree of portal tract inflammation on pretrial biopsy. Our results show that in white children treatment with IFN-alpha, at the dose and duration used in this study, improves the rate of anti-HBe seroconversion. Steroid priming does not potentiate the effect of IFN-alpha.

Catalytic properties of serine proteases. 2. Comparison between human urinary kallikrein and human urokinase, bovine beta-trypsin, bovine thrombin, and bovine alpha-chymotrypsin

The catalytic properties of several serine proteases acting on cationic substrates (bovine of beta-trypsin, bovine thrombin, human urinary kallikrein, and human urokinase) and noncationic substrates (bovine alpha-chymotrypsin) have been compared in steady-state and pre-steady-state experiments by using ester and anilide synthetic substrates. Arginine and lysine derivatives are equally good substrates for b. beta-trypsin; b. thrombin and h.u. kallikrein prefer substrates containing arginine side chains; h. urokinase prefers substrate containing lysine. The preference of the various enzymes for the guanidinium or ammonium group in reflected by the different promotor effect that acetamidine or ethylamine has on the catalyzed hydrolysis of neutral substrates. Pre-steady-state data, analyzed in the framework of the three-step model, show that for b. beta-trypsin, b. thrombin, h.u. kallikrein, and h. urokinase the acylation step (k2) is rate limiting above pH 6 and the deacylation step (k3) below pH 4 in the hydrolysis of ZLysONp and of ZAlaONp in the presence of acetamidine or ethylamine. In the catalyzed hydrolysis of ZAlaONp, in the absence of acetamidine or ethylamine, the acylation step (k2) is rate limiting all over the pH range from 3 to 8. The change in the rate-limiting step with pH is always absent, for the same substrates, in the b. alpha-chymotrypsin catalysis. The results of kinetic and spectral measurements indicate that b. beta-trypsin, b. thrombin, h.u. kallikrein, and h. urokinase, but not b. alpha-chymotrypsin, contain a similarly located ionizable group with a pKa of 4.50 +/- 0.1, in the free enzyme, the ionization of which affects the binding of cationic substrates and ligands, the spectral properties of the pancreas, and the rate of the acylation step in catalysis.

Broad-spectrum toxicological analysis of hair based on capillary zone electrophoresis–time-of-flight mass spectrometry

The coupling of capillary electrophoresis-electrospray ionization and time-of-flight mass spectrometry, combining efficiency and speed of separation with high mass accuracy and fast scanning capability, was for the first time applied to the determination of drugs of abuse (amphetamine, methamphetamine, MDA, MDMA, ephedrine, cocaine, morphine, codeine) and their metabolites in hair (6-MAM, benzoylecgonine). Experimental conditions were as follows. Separation: voltage 15 kV, uncoated fused-silica capillary (75 microm ID, 100 cm total length), running electrolyte 25 mM ammonium formate, pH 9.5, field-amplified sample stacking injection. Forensic drugs could be identified by exact mass determination (mass accuracy typically < or = 5 ppm) and by match of the isotopic pattern. The method was fully validated, showing limit of detections (LODs) suitable for the determination of all the compounds below the cut-off usually adopted for hair analysis (0.1 ng/mg). Analytical precision in real matrices (tested at 0.1 and 1.0 ng/mg) was typically characterized by CV's < or = 24% in both intra-day and day-to-day experiments. Quantitative determination was also tested by using a single internal standard (folcodine). Results, although with a moderate accuracy, conceivably depending on the lack of deuterated internal standards, proved useful for diagnostic use of the results from hair analysis. A single liquid-liquid extraction procedure was applied for all analytes, allowing the detection of a broad spectrum of basic drugs and their major metabolites.

Autoantibody prevalence in chronic hepatitis B virus infection: effect in interferon alfa

The most effective treatment of chronic hepatitis B virus (HBV) infection is interferon alfa (IFN-alpha), a potentially severe side effect of which is the induction of autoimmunity. To assess whether IFN-alpha causes clinical or serological autoimmune manifestations, we studied 61 children randomized to receive 5 MU/m2 of IFN-alpha three times per week for 12 weeks, with or without steroid priming or no treatment. Autoantibodies to antinuclei (ANA), smooth muscle (SMA), gastric parietal cell (GPC), liver kidney microsomal type 1, mitochondrial, liver cytosolic antigen, thyroid microsomal, and thyroid globulin were detected by standard techniques. Over a median of 4 years (range, 1-5 years) from randomization, no clinical signs of autoimmunity were observed. Autoantibody positivity for nuclei, smooth muscle, and/or gastric parietal cells was observed on at least one occasion in 42 of 61 children (69%), with no overall difference in the prevalence between patients treated with interferon alone (19 of 24 [79%]), steroids plus interferon (13 of 20 [65%]), or untreated controls (10 of 17 [59%]). There was also no difference in the autoantibody prevalence before, during, and at follow-up after cessation of treatment in both interferon-treated and interferon-untreated patients. Autoantibodies are common in chronic HBV infection, and their prevalence is uninfluenced by IFN-alpha.

Recent advances in the applications of CE to forensic sciences (2001–2004)

The present article reviews the applications of CE in forensic science covering the period from 2001 until the first part of 2005. The overview includes the most relevant examples of analytical applications of capillary electrophoretic and electrokinetic techniques in the following fields: (i) Forensic drugs and poisons, (ii) explosive analysis and gunshot residues, (iii) small ions of forensic interest, (iv) forensic DNA and RNA analysis, (v) proteins of forensic interest, and (vi) ink analysis.

Purification, inhibitory properties, amino acid sequence and identification of the reactive site of a new serine proteinase inhibitor from oil-rape (Brassica napus) seed

A new serine proteinase inhibitor, rapeseed trypsin inhibitor (RTI), has been isolated from rapeseed (Brassica napus var. oleifera) seed. The protein inhibits the catalytic activity of bovine beta-trypsin and bovine alpha-chymotrypsin with apparent dissociation constants of 3.0 x 10(-10) M and 4.1 x 10(-7) M, at pH 8.0 and 21 degrees C, respectively. The stoichiometry of both proteinase-inhibitor complexes is 1:1. The amino acid sequence of RTI consists of 60 amino acid residues, corresponding to an M(r) of about 6.7 kDa. The P1-P1' reactive site bond has been tentatively identified at position Arg20-Ile21. RTI shows no similarity to other serine proteinase inhibitors except the low molecular weight mustard trypsin inhibitor (MTI-2). RTI and MTI-2 could be members of a new class of plant serine proteinase inhibitors.

Evaluation and optimization of capillary zone electrophoresis with different dynamic capillary coatings for the determination of carbohydrate-deficient transferrin in human serum

Serum transferrin (Tf) comprises several isoforms with up to two complex oligosaccharide chains containing zero to eight sialic acid residues and neutral sugars. The major glycoform, known as tetrasialo-Tf, contains four sialic acid residues and accounts for about 80% of whole Tf in human serum. Carbohydrate-deficient transferrin (CDT) encompasses isoforms that are deficient in carbohydrate chains and consequently in sialic acid residues (including asialo-, monosialo- and disialo-Tf) and is a well known marker for chronic alcohol abuse. Recently capillary zone electrophoresis (CZE) has been reported as a tool extremely effective for the simultaneous, individual, quantitative determination of CDT isoforms. Three CZE methods that feature different dynamic capillary coatings were evaluated and optimized for CDT determination in human serum of alcohol abusers and control subjects. CZE separation was performed in alkaline borate buffers after serum sample saturation with iron, electropherograms were detected at 200 nm, data were evaluated as % area of disialo-Tf in relation to tetrasialo-Tf and peak identification was accomplished via relative migration times to tetrasialo-Tf, immunosubtraction and enzymatic sequential cleavage of sialic acid residues. Dynamic capillary coatings with diaminobutane, spermine and a double coating produced by commercially available proprietary agents were investigated and found to be suitable for determination of CDT in human serum. For all three approaches, best results were obtained in 50 microm I.D. fused-silica capillaries of 50 cm effective length and a capillary cartridge temperature of 20-25 degrees C. Using 3 mM 1,4-diaminobutane or 0.02 mM spermine in a borate-based running buffer of pH 8.3 provided data of remarkable similarity with resolution of di-, tri-, tetra- and pentasialo-Tf within 15-18 min. With the double coating, asialo-Tf and Tf isoforms with two to six sialic acid residues were baseline separated. Compared to the two amine-based procedures, the run times were found to be somewhat shorter, the detector signals higher, the applied power level significantly lower and the reproducibility better.