In vitro and in vivo uroselectivity of B8805-033, an antagonist with high affinity at prostatic alpha1A- vs. alpha1B- and alpha1D-adrenoceptors

We have investigated the pharmacological properties of B8805-033 [(+/-)- 1,3,5-trimethyl-6-[[3-[4-((2,3-dihydro-2-hydroxymethyl)-1,4-benzodioxin-5-yl)-1-piperazinyl]propyl] amino]-2,4(1H,3H)-pyrimidinedione], a new alpha1A-adrenoceptor (AR) selective antagonist. In radioligand binding studies, B8805-033 was 150- to 1200-fold selective for alpha1A-ARs (pKi rat cerebral cortex 8.70, cloned human receptor 7.71) relative to alpha1B-ARs (pKi rat cerebral cortex 5.60, rat liver 5.39, cloned human receptor 5.16) and alpha1D-ARs (pKi cloned human receptor 5.49). B8805-033 inhibited noradrenaline (NA) induced contractions mediated by alpha1A-ARs in rat vas deferens and rabbit and human prostate (pA2 7.62-8.40) much more potently than those mediated by alpha1B-ARs in guinea pig and mouse spleen or by alpha1D-ARs in rat aorta and pulmonary artery (pA2 5.21-5.52). With the exception of a high agonist affinity at 5-HT1A receptors (pKi 9.74 in pig cortex, pD2 6.82 for contraction of rabbit basilar artery) and a moderate to low affinity at histamine H1-receptors (pA2 6.74) and beta1-ARs (pA2 5.75), B8805-033 did not interact with a number of other neurotransmitter receptors (pKi or pA2<5.0). From the i.v. doses of B8805-033 to either inhibit the urethral pressure response to NA by 50% (29 nmol/kg) or to evoke a fall in diastolic blood pressure by 25% (1.54 micromol/kg) in anaesthetized dogs, an urethral/ vascular selectivity ratio of 52 was obtained, far exceeding that found for the nearly unselective prazosin (ratio 1.8). We conclude that B8805-033 is a highly alpha1A-AR selective antagonist, which may potentially be useful as pharmacological tool to investigate alpha1-AR heterogeneity and in the treatment of benign prostatic hyperplasia.

Influence of pump compliance (peristaltic vs. infusion) on urodynamic measurement during cystometry in conscious rats

Cystometry, employing natural or pump-induced bladder filling, is the most widely used method for studying bladder reflexes and micturition in conscious rats. However, discrepancies in basal values of urodynamic parameters are often reported, especially for micturition pressure. The aim of this study was to establish whether the type of pump used (peristaltic or infusion) might yield different urodynamic parameters. Differences between natural filling (evaluated in water-loaded animals and considered "physiological micturition") and pump-evoked cystometrograms, as well as the compliance of these systems, and the effects of pharmacologically diverse drugs (prazosin, oxybutynin, and naproxen) acting on the bladder voiding were evaluated. Micturition pressure recorded from pump-evoked cystometrograms showed differences from natural micturition that were related to the total compliance of the system (pump + tube) and not only to the nature of the pump used. Drug-induced changes of micturition pressure during natural micturition resembled those recorded during bladder infusion with a peristaltic pump more than those with an infusion pump. Other basal values and drug-induced changes of bladder capacity were the same during natural and pump-evoked micturition. The present findings indicate that cystometrographic parameters obtained during pump-evoked micturition with a system at high compliance (peristaltic pump) are equivalent to those observed during physiological micturition.

Long-term follow up of chronic hepatitis C patients after alpha-interferon treatment: a functional study

AIM

To evaluate the long-term functional outcome of chronic hepatitis C (CHC) patients treated with interferon (IFN) therapy.

METHODS

Thirty-six patients with CHC were followed up for a mean of 36 months (+/- 19, SD) after a course of IFN therapy. Biochemical, virological (qualitative hepatitis C virus (HCV)-RNA and HCV genotype), and functional (monoethylglycinexylidide (MEGX) test) evaluations were carried out at the time of liver biopsy. Patients were divided into long-term responders (LTR), relapsers (RR), or non-responders (NR) according to IFN therapy outcome. At the end of follow up, patients were non-invasively re-evaluated by means of biochemistry, qualitative HCV-RNA, MEGX test, and liver ultrasonography.

RESULTS

A significant decrease in MEGX values was observed in all patients. However, when patients were examined according to treatment outcome, only NR and RR showed a significant decrease in liver function as compared to pretreatment levels (MEGX30, 80.5 +/- 26.8-62.9 +/- 24.2 ng/mL, P< 0.01; MEGX60, 72.9 +/- 18.1-60.5 +/- 19.7 ng/mL, P< 0.05; MEGXAUC, 3,816 +/- 1,243-3,095 +/- 1,205 ng/mL per h, P< 0.05). On the contrary, LTR patients showed no significant modifications in MEGX values at each sampling time (MEGX,5, 72.9 +/- 31.4-70.3 +/- 29.7 ng/mL; MEGX30, 84.0 +/- 27.6-71.5 +/- 21.8 ng/ mL; MEGX60, 69.5 +/- 26.8-63.2 +/- 14.4 ng/mL; MEGXAUC 4028 +/- 1,378-3,620 +/- 1,041 ng/mL per h). At the end of follow up, LTR patients showed normal liver biochemistry and negativity of serum HCV-RNA, while NR and RR patients showed a significant decrease in platelets.

CONCLUSIONS

In CHC patients long-term response to IFN therapy, besides favoring positive clinical and virologic long-term outcome, results in maintaining preserved liver function. Furthermore, IFN therapy seems to determine a decrease in the rate of functional disease progression, even in NR and RR. The MEGX test may be considered as a useful tool for performing serial follow up of CHC patients.

Vitamin E intake reduces plasminogen activator inhibitor type 1 in T2DM patients

Previous studies hypothesised that vitamin E could protect against coronary heart disease and vascular complications in diabetes, but no studies have been performed regarding its eventual effects on fibrinolysis. Nevertheless, in Type 2 diabetes mellitus (T2DM) a profound reduction in the fibrinolytic activity has been demonstrated to be involved in vascular complications, probably due to plasminogen activator inhibitor type 1 (PAI-1) overproduction. On this basis we aimed to verify whether an antioxidant treatment with vitamin E is able to lower PAI-1 plasma levels in T2DM. Thirteen T2DM patients (9 males and 4 females; mean age+/-SD, 64.4+/-3.3 yr) were selected through strict admission criteria. These patients were treated with vitamin E (500 IU/die) for 10 weeks. Glyco-lipometabolic, oxidative and haemocoagulative parameters were evaluated at baseline and after 5, 10, 30 and 60 weeks. Vitamin E levels at different times were [median (interquartile range)] 6.1 (5.3-7.7), 8.5 (7.3-9.9), 9.7 (8.9-12.9), 5.6 (4.4-6.8), 5.7 (4.5-7.1) microg/ml, respectively. Significant differences were found for PAI-1 antigen (p=0.006), PAI-1 activity (p=0.028), apolipoprotein B (p=0.015) and antioxidant defence, evaluated as ferric reducing ability of plasma (FRAP) values (p=0.005). Particularly, decrements were detected for PAI-1 antigen between baseline and the 10th week (p<0.05), followed by an increase back to basal at the 30th week. Similar behaviour was found for PAI-1 activity. Regarding the antioxidant defence, FRAP values increased until the 30th week (p<0.05) with a decrease at the 60th week. These results demonstrate that vitamin E is able to lower PAI-1 levels in diabetic patients but this effect does not seem related to improvements of glycometabolic data or to the increase in FRAP values, suggesting that PAI-1 overproduction can be decreased by other effects of vitamin E on endothelial cells.

Increased levels of gammaGT suggest the presence of bile duct lesions in patients with chronic hepatitis C: absence of influence of HCV genotype, HCV-RNA serum levels, and HGV infection on this histological damage

Damage to bile ducts in chronic hepatitis C is a characteristic histological lesion. Moreover, the presence of abnormal levels of gammaGT in these patients is also a common finding. Assessing whether the presence of bile duct lesions is indicated by biochemical abnormalities or whether virological characteristics can influence their development may help in the definition of clinical-histological relationships in chronic hepatitis C. In this study we evaluated the relationships among routine biochemical parameters, serum bile acids, and pi-class glutathione S-transferase levels, and the presence of bile duct lesions in 60 patients with chronic hepatitis C. Furthermore, we assessed whether the presence of bile duct lesion might be related to HCV genotype, HCV-RNA serum levels, and positivity for HGV-RNA. We found that gammaGT was the only parameter related to the presence of bile duct lesions. Although a trend towards higher serum bile acids and pi-class glutathione S-transferase levels was observed in patients with bile duct lesions, this trend did not reach statistical significance. Different HCV genotypes and RNA levels, and HGV-RNA positivity did not seem to influence the presence of bile duct damage. In conclusion we found that gammaGT levels point out the presence of bile duct lesions in patients with chronic hepatitis C. Since we observed a different pattern of alteration of gammaGT, serum bile acids, and pi-class glutathione S-transferase, we suggest that these various biochemical alterations reflect a more complex damage to bile duct structures, which is not likely represented by the common assessment of bile duct lesions. Viral factors such as HCV genotype and RNA levels as well as HGV-RNA positivity are probably not the main cause of this histological damage.

Fast, simple and cost-effective determination of thiopental in human plasma by a new HPLC technique

BACKGROUND

Thiopental is an anaesthetic drug that is largely used in both short-term and long-term infusion. After long-term infusion of thiopental, non-linear and inter-individual-dependent pharmacokinetics occur because of the saturation and/or induction of the metabolism. Clinical monitoring is important so that therapeutic adjustments can be made in many of the different pharmacological treatments, especially when long-term infusion is required. We describe a new, rapid HPLC method for the determination of plasma thiopental.

METHODS

Sample preparation involved precipitation of plasma proteins using a mixture of methanol, zinc sulfate and ethylene glycol, and containing the internal standard 5-ethyl-5-p-tolyl-barbituric acid. After adding trichloroacetic acid, the sample was centrifuged and the supernatant was injected into a C(18) reversed-phase column. The mobile phase used was water-methanol-acetonitrile (50:40:10, v/v). The eluent was monitored at 290 nm.

RESULTS

The calibration curve was linear from 0.2 to 100 microg/mL. Precision, calculated as the coefficient of variation (%), was in the range of 3.62-0.70% for the within-day assay and 5.77-1.51% for the between-day assay. The absolute recoveries obtained from supplemented samples were never less than 100%.

CONCLUSIONS

This technique shows good reliability and seems to be suitable for a very fast and simple therapeutic monitoring of plasma thiopental.

Age-dependent changes of serum oxygen radical scavenger capacity and haemoglobin glycosylation in non-insulin-dependent diabetic patients

BACKGROUND

Contradictory results have been reported in the literature concerning the correlation between glycosylated haemoglobin (HbA1c) and peroxidation level in serum of diabetic patients.

OBJECTIVE

To evaluate this correlation in type 2 diabetic patients by comparing the level of HbA1c with the oxygen radical absorbance capacity (ORAC(OH)) of serum.

METHODS

One hundred and five type 2 diabetic patients were enrolled for the study. After having obtained informed consent, venous blood samples were drawn after overnight fast at the time of routine diabetic check-ups. The blood was collected in plain and EDTA (1 mg/ml) tubes. Glycosylated haemoglobin (HbA1c) was determined by cation-exchange chromatography (HPLC), and spectrophotometric detection (Diamat Analyzer, BioRad). Serum was used for biochemical determinations performed by standard laboratory procedures and for ORAC(OH) analysis. This last parameter was determined measuring the loss of beta-phycoerytrin fluorescence due to oxidation by hydroxyl radicals generated by Cu(2+) and H(2)O(2), in the presence and absence of serum. Seventy-eight control age-matched subjects were obtained from the personnel staff of our Research Department and old healthy subjects, selected on the basis of Senieur Protocol, were relatives of the above mentioned personnel.

RESULTS

When the population of diabetic patients was taken as a whole, a decrease of ORAC(OH) has been observed compared to the controls. Moreover, negative correlations were found comparing ORAC(OH) either with HbA1c (r = -0.213; p = 0.029) and with the age of patients (r = -0.27; p = 0.005). To better understand the effect of age, the data were re-examined dividing the diabetics into two populations, i.e. under and over 65 years of age. An age-dependent decrease of ORAC(OH) and an increase in HbA1c levels has been observed comparing these two populations; however, the correlation between the two parameters remained statistically significant only in the oldest group (r = -0.31; p = 0.026).

CONCLUSIONS

Present data point to an involvement of oxidative stress in the glycation of haemoglobin especially in old diabetic patients, and provide support for the potential use of an antioxidant therapy in these patients, irrespective of their glycaemic control.

Effect of different 5-hydroxytryptamine receptor subtype antagonists on the micturition reflex in rats

OBJECTIVE

To evaluate the effects of antagonists of different subfamilies of 5-hydroxytryptamine (5-HT) receptors on bladder function in anaesthetized and conscious rats. MATEERIALS AND METHODS: The urinary bladder of female anaesthetized rats was catheterized urethrally and filled with physiological saline until spontaneous bladder contractions occurred. Infravesical pressure was measured by a pressure transducer and displayed continuously on a chart recorder. The time of bladder quiescence (to the disappearance of rhythmic contractions) after injection with different compounds tested was recorded. Conscious rats underwent cystometry with chronically (infravesical) implanted catheters to continuously record bladder capacity (evaluated as amount of saline infused between voiding cycles) and maximal voiding pressure. The affinity for the human recombinant serotoninergic 5-HT1A subtype (inhibition of specific binding of [3H]8-hydroxy-2-(di-n-propylamino) tetralin) and the effects on the [35S]guanosine 5'-(gamma-thio) triphosphate (GTPgammaS) binding in HeLa cells was also evaluated.

RESULTS

Among the compounds tested, only 4-(2'-methoxy-phenyl)-1-[2'-(n-2"-pyridinyl)-p-iodobenzamido]-ethyl-piperazine (p-MPPI) and methiothepin showed nanomolar affinity for the 5-HT1A receptors, the former being a neutral antagonist and the latter an inverse agonist in the [35S]GTPgammaS binding model. Intravenous injection of low doses of p-MPPI and methiothepin induced a dose-dependent disappearance of isovolumic bladder contractions in anaesthetized rats (> 10 min). At the highest doses, the dose-response curves were bell-shaped. The amplitude of bladder contractions was not markedly altered. The tested antagonists of 5-HT2, 5-HT3, 5-HT4, and 5-HT6 serotoninergic subtypes were poorly active or inactive in the model. Similarly, these compounds were inactive on cystometry in conscious rats, whereas p-MPPI and methiothepin induced a consistent increase in bladder capacity. Methiothepin also decreased the voiding pressure, whereas p-MPPI did not affect this variable.

CONCLUSIONS

These findings confirm that only selective 5-HT1A receptor antagonists have favourable effects on the bladder, inducing an increase in bladder capacity with no derangement of bladder contractility.

Serum pro-collagen III peptide levels are related to lobular necrosis in untreated patients with chronic hepatitis C

OBJECTIVE

Liver biopsy is mandatory for correctly grading and staging chronic hepatitis activity. Nevertheless, serum markers of fibrogenesis may be useful to help us understand the mechanisms of the fibrogenic process, to follow-up patients, and to establish the efficacy of therapy. In this study, our aim was to identify the relationships between pro-collagen III peptide (PIIIP) serum levels and detailed liver histology in a group of untreated patients with chronic hepatitis C (CHC).

METHODS

We studied 147 CHC patients. Correlation analysis of PIIIP serum levels was performed in 109 patients, after having excluded those with alcohol abuse or concomitant hepatitis B virus infection. PIIIP serum levels were assessed using an assay that measures both Col 1-3 peptide (reflecting collagen synthesis) and Col 1 peptide (reflecting collagen degradation). Relationships of serum PIIIP with histology was carried out by evaluating grading and staging separately. Moreover, each component of the necro-inflammatory score was also taken into consideration.

RESULTS

PIIIP levels were abnormal in 101 patients (93%). Moreover, PIIIP levels were no different between patients with (12.1 +/- 6.3 ng/ml) or without (13 +/- 5.8 ng/ml) fibrosis. In univariate analysis, no relationship was observed with fibrosis (rs = 0.033, not significant), while PIIIP levels were significantly correlated with lobular necrosis only (rs = 0.295, P = 0.0020). Multivariate analysis confirmed this latter finding (P = 0.0150). Among biochemical parameters, PIIIP showed relationships with aminotransferase (AST, rS = 0.294, P = 0.0022; ALT, rs = 0.236, P = 0.0142) and alkaline phosphatase (rs = 0.146, P = 0.0223).

CONCLUSIONS

In patients with CHC, serum PIIIP levels reflect histological parameters strictly related to fibrogenesis. Therefore, PIIIP is a useful tool to evaluate ongoing fibrogenic activity of CHC. A complete histological score is needed in order to understand the relationships between biochemical markers of fibrogenesis and histology.

Clinical evidence for myocardial derecruitment downstream from severe stenosis: pressure-flow control interaction

To verify the interaction between coronary pressure (CP) and blood flow (CBF) control, we studied nine candidates for angioplasty of an isolated lesion of the left anterior descending coronary artery [i.e. , percutaneous transluminal coronary angioplasty (PTCA)]. CBF (i.e., flow velocity x coronary cross-sectional area at the Doppler tip) and CP were monitored during washout of 2-5 mCi of (133)Xe after bolus injection into the left main artery before and after PTCA. Xe mean transit time (MTT) was calculated as the area under the time-activity curve, acquired by a gamma camera, divided by the dose obtained from a model fit of the Xe curve in the anterior wall. CBF response to intracoronary adenosine (2 mg) was also assessed. PTCA increased baseline CBF (from 14.5 +/- 9.4 to 20 +/- 8 ml/min, P < 0.01), coronary flow reserve (from 1.52 +/- 0.24 to 2.33 +/- 0.8, P < 0.01), and CP (from 64 +/- 9 to 100 +/- 10 mmHg, P < 0.05). MTT decreased from 89 +/- 32 to 70 +/- 19 s (P < 0.05) after PTCA; however, MTT and CBF changes were not correlated (r = -0.09, not significant). Inasmuch as MTT is the ratio of distribution volume to CBF, MTT x CBF was used as an index of perfused myocardial volume. Volume increased after PTCA from 23 +/- 18 to 56 +/- 30 ml. A direct correlation was observed between the percent increase in distal CP and percent increase in perfused volume (r = 0.91, P < 0.01). Thus low CP was not associated with exhaustion of flow reserve but, rather, with reduction of perfused myocardial volume. These data suggest that, in the presence of a severe coronary stenosis, derecruitment of vascular units occurs that is proportional to the decrease in driving pressure. Residual perfused units maintain a vasomotor tone, thus explaining the paradoxical persistence of coronary reserve.

Leptin has no role in determining severity of steatosis and fibrosis in patients with chronic hepatitis C

OBJECTIVE

The presence of steatosis is a common histological finding in patients with chronic hepatitis C (CHC). The causes of the severity of this condition are not yet clear, although both metabolic and viral factors supposedly are involved. In this study our aim was to examine the possible influence that leptin levels, hepatitis C virus (HCV) RNA levels, and hepatitis G virus (HGV) infection have on the severity of steatosis and on the presence and degree of fibrosis in patients with CHC.

METHODS

One hundred eighty-two CHC patients with histological findings of steatosis were chosen from among a cohort of patients referred to our center for staging of liver disease. Among them 48 CHC patients were accurately selected so as to rule out possible confounding factors for the presence of steatosis (diabetes mellitus, hyperlipemia, obesity, alcohol). Leptin levels, HCV RNA levels, and HCV genotype, and the presence of HGV RNA were assessed in these patients and related to histological findings.

RESULTS

We found that leptin levels in CHC patients were similar to those in healthy subjects. No relationship was found between leptin levels and severity of steatosis. HCV RNA levels, HCV genotype, and the presence of HGV infection were no different among CHC patients with various degrees of steatosis. Leptin was not related to different degrees of fibrosis, whereas higher viral load was the only parameter associated to higher fibrosis scores.

CONCLUSIONS

These findings suggest that the degree of steatosis in patients with CHC does not seem to depend on serum leptin levels or on viral factors, at least as far as HCV viremia and genotype and HGV infection are concerned. The severity of fibrosis does not seem to be influenced by leptin levels, whereas HCV viral load does seem to play some role.

Leptin has no role in determining severity of steatosis and fibrosis in patients with chronic hepatitis C

OBJECTIVE

The presence of steatosis is a common histological finding in patients with chronic hepatitis C (CHC). The causes of the severity of this condition are not yet clear, although both metabolic and viral factors supposedly are involved. In this study our aim was to examine the possible influence that leptin levels, hepatitis C virus (HCV) RNA levels, and hepatitis G virus (HGV) infection have on the severity of steatosis and on the presence and degree of fibrosis in patients with CHC.

METHODS

One hundred eighty-two CHC patients with histological findings of steatosis were chosen from among a cohort of patients referred to our center for staging of liver disease. Among them 48 CHC patients were accurately selected so as to rule out possible confounding factors for the presence of steatosis (diabetes mellitus, hyperlipemia, obesity, alcohol). Leptin levels, HCV RNA levels, and HCV genotype, and the presence of HGV RNA were assessed in these patients and related to histological findings.

RESULTS

We found that leptin levels in CHC patients were similar to those in healthy subjects. No relationship was found between leptin levels and severity of steatosis. HCV RNA levels, HCV genotype, and the presence of HGV infection were no different among CHC patients with various degrees of steatosis. Leptin was not related to different degrees of fibrosis, whereas higher viral load was the only parameter associated to higher fibrosis scores.

CONCLUSIONS

These findings suggest that the degree of steatosis in patients with CHC does not seem to depend on serum leptin levels or on viral factors, at least as far as HCV viremia and genotype and HGV infection are concerned. The severity of fibrosis does not seem to be influenced by leptin levels, whereas HCV viral load does seem to play some role.

Plasma glycohydrolase levels in patients with type 1 diabetes at onset and in subjects undergoing an intravenous glucose tolerance test

The effect of hyperglycemia and insulin deficiency on the plasma level of lysosomal glycohydrolases, namely N-acetyl-beta-D-glucosaminidase, beta-D-glucuronidase, alpha-D-galactosidase, and alpha-D-glucosidase, was investigated. Two patient groups were assessed: (1) 28 children with type 1 diabetes at onset (fasting blood glucose, 444+/-154 mg/100 mL; hemoglobin A1c, 11.9%+/-2.4%; symptom duration, 15.9+/-8 days; and absence of complications), (2) 14 adult subjects undergoing an intravenous glucose tolerance test (IVGTT), consisting of 8 non-obese subjects (body mass index, 26+/-0.04 kg/m2; fasting blood glucose, 82+/-13 mg/100 mL; blood insulin, 6+/-0.04 mU/L) and 6 obese subjects (fasting blood glucose, 97+/-3.5 mg/100 mL; blood insulin, 27+/-6 mU/L, with normal oral glucose tolerance test). Enzyme activity was determined with the fluorimetric method. The mean level of all evaluated enzymes was significantly increased in patients with type 1 diabetes at diagnosis compared with normal controls. Increased enzyme levels were also detected in the group of adults undergoing an IVGTT in whom hyperglycemia was accompanied by insulin resistance (ie, obese subjects). Glycohydrolase abnormalities appear to be related to insulin deficiency rather than hyperglycemia. Lysosomal apparatus abnormalities seem to be an inherent feature of diabetes that is present at disease onset. The possible role of insulin in the regulation of plasma glycohydrolase levels is discussed.

Fibronectin and lipoprotein(a) are inversely related to plasminogen activator inhibitor type-1 levels in Type 2 diabetic patients without complications

Plasminogen activator inhibitor type-1 (PAI-1), the most important physiological fibrinolysis inhibitor, is considered an independent factor of cardiovascular risk in Type 2 diabetes mellitus (T2DM). In previous papers we demonstrated that a T2DM population without complications presents: 1) PAI-1 not increased with respect to a control group; and 2) a negative correlation between PAI-1 and lipoprotein(a) [Lp(a)], suggesting that in these subjects PAI-1 levels could be modulated by the "endothelial stress" induced by Lp(a) and diabetes. This work has been performed in order to better verify this intriguing hypothesis, and the endothelial stress has been evaluated through a marker of endothelial damage, fibronectin (FNC). For this purpose we chose a T2DM population without complications (n=73) and a control group (n=46). Plasma concentrations of FNC, Lp(a), PAI-1 antigen and activity, and the main parameters of lipo- and glycometabolic balance were determined. Fibronectin was significantly higher in diabetics with respect to controls (p<0.01). As expected, significant correlation between PAI-1 antigen, PAI-1 activity and Lp(a) (r=-0.54,p<0.01 and r=-0.39,p<0.01, respectively) was found only in diabetic patients. In the same group FNC showed a significant correlation with PAI-1 antigen and activity (r=-0.49,p<0.01 and r=-0.47; p<0.01, respectively), while no relationship was found between Lp(a) and FNC. Multiple regression analysis showed statistically significant correlation between PAI-1 antigen and PAI-1 activity with FNC and Lp(a) in diabetic patients without complications (p<0.05). These data suggest that in absence of complications, the endothelium is able to modulate PAI-1 levels, favouring in that way the fibrinolytic pathway and, subsequently, the recovery of the endothelial integrity. This modulation seems to be related to parameters such as Lp(a) and FNC, although the mechanisms of the endothelial stress of these two molecules seem to be different.

Influence of Helicobacter pylori eradication therapy on 13C aminopyrine breath test: comparison among omeprazole-, lansoprazole-, or pantoprazole-containing regimens

OBJECTIVE

Proton pump inhibitors and antimicrobial agents are widely used to eradicate Helicobacter pylori (H. pylori) infection. In the general population the prevalence of infection and of polypharmacy increases the possibility of drug-drug interactions during H. pylori eradication therapy. The purpose of the present study was to assess the prevalence, degree, and clinical relevance of metabolic interference with the cytochrome P450 enzymatic system occurring during 1 wk of administration of omeprazole, lansoprazole, or pantoprazole followed by the association of clarithromycin and metronidazole for another week. The 13C aminopyrine breath test (ABT) was chosen to screen for possible interactions.

METHODS

We studied 30 patients referred to our Unit for H. pylori eradication therapy. They were randomized to receive either omeprazole (20 mg b.i.d.), lansoprazole (30 mg b.i.d.), or pantoprazole (40 mg b.i.d.) for 2 wk. During the second week clarithromycin (250 mg b.i.d.) and metronidazole (500 mg b.i.d.) were added. ABT was performed before, and at the end of the first and second week of therapy. Percentage of the administered dose of 13C recovered per hour at the peak (percent 13C dose/h at the peak) and cumulative percentage of administered dose of 13C recovered over time at 120 min (percent 13C dose cum120) were the ABT evaluated parameters.

RESULTS

At baseline all patients showed a normal liver function. In individual patients during treatment we observed various liver metabolic interactions both as inhibition and induction, as well as after the first and the second week of therapy. However, mean modifications of the ABT parameters during the 2 weeks of therapy were not statistically significant compared to baseline values. None of the patients who had ABT variations complained of side effects.

CONCLUSIONS

H. pylori eradication therapy interferes with cytochrome P450-dependent liver metabolic activity. However, the clinical relevance of these metabolic interactions is not yet apparent, and further investigation is needed. H. pylori eradication therapy appears safe, but these interactions should be considered in the choice of proton pump inhibitor and antimicrobial agents.

Does surveillance for hepatocellular carcinoma in HCV cirrhotic patients improve treatment outcome mainly due to better clinical status at diagnosis?

BACKGROUND/AIMS

Cirrhotic patients with hepatitis C virus infection are a group at higher risk for hepatocellular carcinoma. Conventional screening programs detect only few early hepatocellular carcinomas that are eligible for radical treatment. Our aim was to compare characteristics of patients, modality of treatment, and outcome in anti-HCV positive cirrhotics with hepatocellular carcinoma diagnosed during follow-up, or incidentally.

METHODOLOGY

Sixty-one hepatocellular carcinomas were consecutively diagnosed in cirrhotic anti-HCV patients from 1993-1998 among which 34 during biannual ultrasonographic-biochemical follow-up and the others incidentally. Child-Pugh's score, alpha-fetoprotein levels, uni- or multifocality of the tumor, and treatment and survival of the patients were then analyzed on the basis of modality of diagnosis.

RESULTS

Surgical treatment was feasible only in a minority of patients. Radical and palliative treatment was more frequent among patients with HCC diagnosed during follow-up. Child-Pugh's score was lower in these patients, moreover their survival rate was better. Analysis of survival of patients treated with the same procedure and grouped by modality of diagnosis did not demonstrate any differences. Regression analysis showed that patients with a lower Child-Pugh's score, one nodule, with a tumor diagnosed during follow-up and who were treated had a better survival rate.

CONCLUSIONS

In our population surveillance did not detect a higher percentage of curable HCC. Nevertheless the results of palliative treatment and of curative treatment overlapped. Overall better outcome was observed in patients with preserved liver function whatever the treatment. Surveillance allowed us to diagnose HCC in patients with these characteristics thus leading to an improved survival rate.

The monoethylglycinexylidide test does not impair psychometric performance in patients with chronic hepatitis or cirrhosis

Lidocaine (LID) is an aminoethylamide used in hepatology to perform the monoethylglycinexylidide (MEGX) test for the evaluation of liver function in patients with cirrhosis (CIR) or chronic hepatitis (CH). The authors evaluated whether the MEGX test changes psychometric performance in patients with chronic liver disease and, in particular, whether it might trigger subclinical portosystemic encephalopathy in patients with CIR. Thirty patients with CIR and 20 patients with CH were studied. They underwent a standard-dose MEGX test, before and after which a psychometric test was administered and blood pressure, heart rate, and adverse effects were recorded. The MEGX test did not modify psychometric performance. Mean arterial blood pressure and heart rate did not change at the end of the MEGX test in either patients with CH or CIR. Adverse effects were present in 66% of all patients during lidocaine injection and lasted up to 3 minutes afterwards. They were more frequent in patients with CH than in patients with CIR (85% vs 53%). No relationship was found between adverse effects and lidocaine dosage, nor between adverse effects and MEGX or lidocaine concentration at 15 minutes. Standard-dose MEGX test does not worsen or trigger portosystemic encephalopathy in CIR. Adverse effects were frequent but mild.

Histologic determinants of monoethylglycinexylidide formation in patients with chronic hepatitis C

Patients affected by chronic hepatitis C (CHC) display a peculiar histologic picture characterized by the presence of steatosis and bile duct damage in addition to evidence of inflammation, necrosis, and fibrosis. In the staging of these patients, functional evaluation may be considered a complementary tool. The monoethylglycinexylidide (MEGX) test has been used in diagnostic and prognostic assessment of chronic liver disease as a quantitative liver function test. In this study the authors evaluated whether different sampling times for the test could reflect different histologic patterns. The authors studied 82 patients with biopsy-proven CHC who underwent functional evaluation by means of MEGX test. The authors found that MEGX15 better reflected the histologic findings of necrosis and inflammation, and MEGX60 the presence of fibrosis. Neither steatosis nor bile duct damage showed a strong correlation with either sampling time. Moreover, MEGX levels showed a progressive decrease as histologic grading of chronic hepatitis progressively increased. Stepwise regression analysis identified necrosis and inflammation as histologic variables associated with both MEGX15 and MEGX30, and fibrosis as a variable associated with MEGX60. These results suggest that a decline in liver metabolic function corresponds to a progressive increase in liver damage, and that this circumstance should be taken into account when prescribing drugs to patients with CHC.