The coeliac iceberg in Italy. A multicentre antigliadin antibodies screening for coeliac disease in school-age subjects

BACKGROUND

Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy.

PATIENTS AND METHODS

Fifteen centres screened 17,201 students aged 6-15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency.

RESULTS

Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 x 1000 (95% CI 3.79-5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 x 1000 (95% CI 4.57-6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7.

CONCLUSIONS

These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched.

Infliximab heals intestinal inflammatory lesions and restores growth in children with Crohn's disease

BACKGROUND

Infliximab has recently emerged as an efficacious agent for patients with severe Crohn's disease. There are only few studies on the use of infliximab in children with Crohn's disease: most of them are retrospective and deal only with the clinical response to the drug.

AIM

We aimed at assessing the efficacy of infliximab in children and adolescents with severe Crohn's disease recruited consecutively and followed up prospectively at a single centre. Clinical response, intestinal inflammation and growth pattern were evaluated.

PATIENTS

Eighteen patients entered into the trial (median age: 13 years, range: 6-18). They were referred because of severe symptoms with unsatisfactory response to conventional drugs.

METHODS

All patients received a baseline schedule of three intravenous infusions of infliximab (0, 2 and 6 weeks), 5 mg/kg. Paediatric Crohn's Disease Activity Index, nutritional and activity serum variables, and ileocolonoscopy (with histology) were evaluated before and 8 weeks after beginning the therapy. All patients had long-term administration of azathioprine (2 mg/kg per day). After the baseline schedule, eight patients had a retreatment infusion of infliximab (5 mg/kg) every 8 weeks. Weight and height Z scores were measured before starting the baseline infusion programme and after 6 months.

RESULTS

After 8 weeks of therapy, there was a dramatic improvement in Paediatric Crohn's Disease Activity Index, in nutritional and activity blood parameters, as well as in endoscopic and histological scores; 10 patients had a clinical remission (Paediatric Crohn's Disease Activity Index < or = 10), 12 patients had an inflammatory remission (decrease in both endoscopic and histological scores for > or = 50% as compared to baseline values). In all patients corticosteroids were stopped within 4 weeks after beginning infliximab therapy. After 6 months of therapy, Paediatric Crohn's Disease Activity Index was markedly lower than the pre-treatment value; however, it was significantly lower in patients on retreatment than in those who received only three infusions of infliximab. Furthermore, a significant increase in both weight and height Z scores was observed 6 months after beginning of the baseline infusion programme. Moreover, weight and height gain was significantly higher in patients on retreatment rather than in those treated only with three baseline infusions of infliximab. Mild infusion reactions controlled by slowing infusion rate were observed in four patients. No delayed hypersensitivity-like reactions were seen.

CONCLUSIONS

In children with severe Crohn's disease, infliximab is a safe and valuable treatment in inducing remission, in healing inflammatory lesions of the gut, as documented by endoscopy and histology, and in promoting growth. Retreatment infusions of infliximab may be suggested in childhood-onset Crohn's disease to maintain remission and reverse growth failure.

AAV-mediated photoreceptor transduction of the pig cone-enriched retina

Recent success in clinical trials supports the use of adeno-associated viral (AAV) vectors for gene therapy of retinal diseases caused by defects in the retinal pigment epithelium (RPE). In contrast, evidence of the efficacy of AAV-mediated gene transfer to retinal photoreceptors, the major site of inherited retinal diseases, is less robust. In addition, although AAV-mediated RPE transduction appears efficient, independently of the serotype used and species treated, AAV-mediated photoreceptor gene transfer has not been systematically investigated thus so far in large animal models, which also may allow identifying relevant species-specific differences in AAV-mediated retinal transduction. In the present study, we used the porcine retina, which has a high cone/rod ratio. This feature allows to properly evaluate both cone and rod photoreceptors transduction and compare the transduction characteristics of AAV2/5 and 2/8, the two most efficient AAV vector serotypes for photoreceptor targeting. Here we show that AAV2/5 and 2/8 transduces both RPE and photoreceptors. AAV2/8 infects and transduces photoreceptor more efficiently than AAV2/5, similarly to what we have observed in the murine retina. The use of the photoreceptor-specific rhodopsin promoter restricts transgene expression to porcine rods and cones, and results in photoreceptor transduction levels similar to those obtained with the ubiquitous promoters tested. Finally, immunological, toxicological and biodistribution studies support the safety of AAV subretinal administration to the large porcine retina. The data presented here on AAV-mediated transduction of the cone-enriched porcine retina may affect the development of gene-based therapies for rare and common severe photoreceptor diseases.

Prevalence of coeliac disease in idiopathic dilated cardiomyopathy

We examined 52 patients with idiopathic cardiomyopathy (IDCM) for coeliac disease. Three of them had coeliac disease, suggesting that prevalence of coeliac disease in IDCM patients is increased.

The squalene-2,3-epoxide cyclase as a model for the development of new drugs

The 2,3-oxido squalene (SO) cyclases represent a group of enzymes which convert SO into polycyclic triterpenoids such as lanosterol, cycloartenol, cucurbitadienol and beta-amyrin. Taking into account the postulated model of the enzymatic cyclization of SO, we have investigated the possibility of designing compounds that would be selective and potent inhibitors of SO cyclases. Due to the fundamental role of sterols in animal, higher plant and fungal tissues, these inhibitors might behave as very selective (ipocholesterolemic, antifungal or phytotoxic) drugs. Our first approach was the synthesis and biological evaluation of 2-aza-2,3-dihydrosqualene and its derivatives which, being protonated at physiological pH, would present some similarities to the C-2 carbon ion generated by the opening of the oxirane ring of SO. Microsomes from different sources (germinated pea cotyledons, maize seedlings, rat liver and yeasts) were utilized to determine the inhibition values (I50: concentration of inhibitor producing 50% inhibition at a given substrate concentration). From the results obtained so far we conclude that 2-aza-2-dihydrosqualene and its derivatives strongly inhibited the cyclases, the site of the enzyme responsible for binding to the inhibitor is quite sensitive to the steric hindrance, and the degree of the inhibitory activity is greater in higher plants than in rat liver or fungi.

2,3-Epoxy-10-aza-10,11-dihydrosqualene, a high-energy intermediate analogue inhibitor of 2,3-oxidosqualene cyclase

2,3-Epoxy-10-aza-10,11-dihydrosqualene, a high-energy intermediate analogue inhibitor of 2,3-oxidosqualene (SO) cyclase was obtained by total synthesis. This involved the preparation of three main building blocks: (1) C17 squalenoid N-methylamine, (2) 3-(diphenylphosphinoyl)propanal, and (3) 5,6-epoxy-6-methylheptan-2-one. The final stages of the reconstruction of the 6E double bond were obtained by a Wittig-Horner reaction which was modified for poorly reactive systems. This compound was designed to mimic the C-8 carbonium ion formed during SO cyclization. Its inhibitory activity on various SO cyclases was evaluated and compared with the 6 Z isomer which has an unfavorable geometry. Only isomer 6 E, the carbocation analogue, was active on SO cyclases from rat liver, pig liver, S. cerevisiae, and C. albicans microsomes, with an I50 varying from 3 to 5 microM. Both E and Z isomers were inactive on squalene epoxidase at the higher concentrations tested.

Vinyl sulfide derivatives of truncated oxidosqualene as selective inhibitors of oxidosqualene and squalene-hopene cyclases

Various vinyl sulfide and ketene dithioacetal derivatives of truncated 2,3-oxidosqualene were developed. These compounds, having the reactive functions at positions C-2, C-15 and C-19 of the squalene skeleton, were studied as inhibitors of pig liver and Saccharomyces cerevisiae oxidosqualene cyclases (OSC) (EC 5.4.99.7) and of Alicyclobacillus acidocaldarius squalene hopene cyclase (SHC) (EC 5.4.99.-). They contain one or two sulfur atoms in alpha-skeletal position to carbons considered to be cationic during enzymatic cyclization of the substrate and should strongly interact with enzyme nucleophiles of the active site. Most of the new compounds are inhibitors of the OSC and of SHC, with various degrees of selectivity. The methylthiovinyl derivative, having the reactive group at position 19, was the most potent and selective inhibitor of the series toward S. cerevisiae OSC, with a concentration inhibiting 500% of the activity of 50 nM, while toward the animal enzyme it was 20 times less potent. These results could offer new insight for the design of antifungal drugs.

Idiopathic dilated cardiomyopathy associated with coeliac disease: the effect of a gluten-free diet on cardiac performance

An increased incidence of coeliac disease has recently been reported in patients with idiopathic dilated cardiomyopathy. This report deals with three patients with idiopathic dilated cardiomyopathy and coeliac disease who underwent clinical and laboratory evaluation to establish the effect of a gluten-free diet on cardiac performance. Two patients observed the gluten-free diet regimen very strictly, and, after a 28-month follow-up period, showed an improvement in echocardiographic parameters as well as in cardiological features and quality of life, as evaluated by the Minnesota Living with Heart Failure questionnaire and the Gastrointestinal Symptom Rating Scale questionnaire. The third patient did not observe the gluten-free diet and presented a worsening in the echocardiographic parameters and cardiological symptoms which required supplementary drug therapy. These preliminary data appear to suggest that the gluten-free diet may have a beneficial effect on cardiac performance in patients with idiopathic dilated cardiomyopathy.

HCV core immunodominant region analysis using mouse monoclonal antibodies and human sera: characterization of major epitopes useful for antigen detection

Monoclonal antibodies (MAbs) were generated by immunizing mice with a truncated recombinant protein corresponding to the immunodominant region (residues 1-120) of hepatitis C virus (HCV) nucleocapsid protein. The specific recognition by either human sera or mouse monoclonal antibodies of overlapping peptides spanning the core region 1-120 as well as the comparison with epitopes described earlier allowed the fine mapping of HCV core. Within the region 1-120, the major antigenic domain could be restricted to the first 45 amino acids. Indeed, the peptide S42G (residues 2-45) allowed the detection of an anti-HCV core response by all anticore-positive human sera examined. According to their epitope localization, three groups of mouse MABs could be evidenced that were directed against different regions of core. Group II MAbs recognized a strictly linear epitope (QDVKF, residues 20-24), whereas group I MABs were directed against a conformational epitope mainly located at the amino acid residues (QIVGG, 29-33). The epitope of group III MABs was also conformational (PRGRRQPI, residues 58-65). These three epitopes appeared close but different from the three major human epitopes RKTKRNTN, VYLLPR, and GRTWAQPGYPWPLY (residues 7-17, 34-39, and 73-86, respectively). Group II MAB 7G12A8 and group I MAB 19D9D6 were used in a sandwich ELISA for the capture and the detection, respectively, of viral core antigen in sera of patients with chronic HCV infection. After treatment of sera with triton x 100 in acidic conditions, amounts of viral antigen as low as 20 pg/ml of sera could be detected.

Azide, cyanide, fluoride, imidazole and pyridine binding to ferric and ferrous native horse heart cytochrome c and to its carboxymethylated derivative: a comparative study

Azide, cyanide, fluoride, imidazole, and pyridine binding to ferric and ferrous native horse heart cytochrome c and to its carboxymethylated derivative has been investigated, from the thermodynamic viewpoint, at pH 7.5 and 25.0 degrees C. Ligand affinity for ferric and ferrous carboxymethylated cytochrome c is higher by about 30- and 400-fold, respectively, than that observed for the native protein. The results here reported: (i) allow the estimation, for the first time, of the ligand-independent free energy associated with the heme-iron sixth coordination bond in ferric and ferrous native cytochrome c, which turns out to be +8.4 kJ mol-1 and +14.6 kJ mol-1, at 25.0 degrees C, respectively, and (ii) suggest an interplay between redox, structural, ligand binding, and recognition properties of cytochrome c.

Inhibition of sterol biosynthesis in Saccharomyces cerevisiae by N,N-diethylazasqualene and derivatives

The ability of some azasqualene derivatives to inhibit yeast cell growth was compared with their inhibition activity on squalene-2,3-oxide cyclase (EC 5.4.99.7) both in living cells and in microsome preparations. Among the compounds tested, N,N-diethylazasqualene showed the best correlation between the activity on squalene-2,3-oxide cyclase and its inhibition of yeast growth. The N-oxide derivative, N,N-diethylazasqualene N-oxide, which was as active as the amine in microsomes, was much less active in living cells, probably because it could not easily penetrate the cell wall. Kinetic analysis of the inhibitory activity of compounds on squalene-2,3-oxide cyclase revealed a sharp difference between N,N-diethylazasqualene and its N-oxide; the former showed a non-competitive-type inhibition, whereas the latter behaved as a competitive inhibitor.

Subcellular localization of oxidosqualene cyclases from Arabidopsis thaliana, Trypanosoma cruzi, and Pneumocystis carinii expressed in yeast

Cycloartenol synthase from Arabidopsis thaliana and lanosterol synthase from Trypanosoma cruzi and Pneumocystis carinii were expressed in yeast, and their subcellular distribution in the expressing cells was compared. Determination of enzymatic (oxidosqualene cyclase, OSC) activity and SDS-PAGE analysis of subcellular fractions proved that enzymes from T. cruzi and A. thaliana have high affinity for lipid particles, a subcellular compartment rich in triacylglycerols, and steryl esters, harboring several enzymes of lipid metabolism. In lipid particles of strains expressing the P. carinii enzyme, neither OSC activity nor the electrophoretic band at the appropriate M.W. were detected. Microsomes from the three expressing strains retained some OSC activity. Affinity of enzymes from A. thaliana and T. cruzi for lipid particles is similar to that of OSC of Saccharomyces cerevisiae, which is mainly located in this compartment. A different distribution of OSC in yeast cells suggests that they differ in some structural features critical for the interaction with the surface of lipid particles. Computer analysis supports the hypothesis of the structural difference since OSC from S. cerevisiae, A. thaliana, and T. cruzi lack or contain only one transmembrane spanning domain (a structural feature that makes a protein poorly inclined to associate with lipid particles), whereas OSC from P. carinii possesses six transmembrane domains. In the strain expressing cycloartenol synthase from A. thaliana, the accumulation of lipid particles largely exceeded that of the other strains.

Drug design based on biosynthetic studies: synthesis, biological activity, and kinetics of new inhibitors of 2,3-oxidosqualene cyclase and squalene epoxidase

Various classes of inhibitor of 2,3-oxido squalene cyclase have been synthesized and tested on rat liver and Saccharomyces cerevisiae microsomes, 3T3 fibroblast cultures, and various bacteria, fungi, and yeasts. The compounds include azasqualenes, azasqualanes, bis-azasqualenes, bis-azasqualanes, and N-oxide and ammonium derivatives of squalene. In order to better mimic the transition state involved in the SN2-like opening of 2,3-oxidosqualene, we synthesized squalene N-methyloxaziridine. Other derivatives tested were N-methylimine, aminalic hydroperoxide, and N-methylamide. We also attempted to produce new "suicide" inhibitors of SO cyclase, such as a squalenoid epoxide vinyl ether. Many of the products described inhibited the various cyclases, the best having an IC50 of 0.3 microM on plants and 1.5 microM on rat liver microsomes, and good antibacterial and antifungal activity. In a search for inhibitors of squalene epoxidase, a series of mono- and bifunctional squalenoid acetylenes and allenes were synthesized. Some of them proved to be inhibitors of squalene epoxidase.

Inhibition of cholesterol biosynthesis in 3T3 fibroblasts by 2-aza-2,3-dihydrosqualene, a rationally designed 2,3-oxidosqualene cyclase inhibitor

The effect of 2-aza-2,3-dihydrosqualene, a new compound designed to inhibit the 2,3-oxidosqualene-lanosterol cyclase [A. Duriatti et al., Biochem. Pharmac. 34, 2765 (1985)] was studied as inhibitor of cholesterol biosynthesis in Swiss 3T3 fibroblasts. Treatment with the drug of cells which were grown for 2 days in a delipidated medium resulted in a marked decrease of [14C]acetate incorporation into the C27-sterol fraction. An IC50 = 0.3 microM was calculated when the cells were preincubated for a period of 4 hr with 2-aza-2,3-dihydrosqualene. This inhibition was correlated with an intracellular accumulation of 2,3-[14C]oxidosqualene and of 2,3:22,23-[14C]dioxidosqualene, indicating that the cyclase was indeed an intracellular target of the drug. A precursor-product relationship of the accumulated [14C]squalene oxide(s) and the [14C]sterols was demonstrated in chase experiments in the absence of drug. Sterols more polar than cholesterol were also detected in treated fibroblasts and in the cells which underwent chase experiments; they were mainly composed of 24,25-epoxycholesterol. The C27-[14C]sterols of [14C]acetate pulse labeled cells consisted in a mixture of desmosterol and cholesterol; treatment of the cells with 2-aza-2,3-dihydrosqualene resulted in a decreased conversion of desmosterol into cholesterol indicating that the delta 24-sterol reductase might be another target of the drug. 2-Aza-2,3-dihydrosqualene at 1 microM affected normal growth of 3T3 fibroblasts, this effect could be prevented by addition of exogeneous cholesterol (50 microM). Growth arrest of the treated cells was correlated with a decrease in cellular sterol content to less than 40% of controls. About 30% of the C27-sterol fraction, of the treated cells, was desmosterol. Our work demonstrates that 2-aza-2,3-dihydrosqualene is a valuable new inhibitor of cholesterol biosynthesis in mammalian cells.

Characterization and partial purification of squalene-2,3-oxide cyclase from Saccharomyces cerevisiae

The membrane nature of squalene oxide cyclase from Saccharomyces cerevisiae was investigated by comparing properties of the enzyme recovered from both microsomes and the soluble fraction of the yeast homogenate. The "apparent soluble" form and microsomal form of the enzyme were both stimulated by the presence of mammalian soluble cytoplasm and corresponded to one another in response to detergents Triton X-100 and Triton X-114. The observed strong dependence of the enzyme activity on the presence of detergents and the behavior of the enzyme after Triton X-114 phase separation were peculiar to a lipophilic membrane-bound enzyme. A study of the conditions required to extract the enzyme from microsomes confirmed the lipophilic character of the enzyme. Microsomes, exposed to ipotonic conditions to remove peripheral membrane proteins, retained most of the enzyme activity within the integral protein fraction. Quantitative dissociation of the enzyme from membranes occurred only if microsomes were treated with detergents (Triton X-100 or octylglucoside) at concentrations which alter membrane integrity. The squalene oxide cyclase was purified 140 times from yeast microsomes by (a) removal of peripheral proteins, (b) extraction of the enzyme from the integral protein fraction with octylglucoside, and (c) separation of the solubilized proteins by DEAE Bio-Gel A chromatography. Removal of the peripheral proteins seemed to be a key step necessary for obtaining high yields.

Inhibition of bovine beta-trypsin, human alpha-thrombin and porcine pancreatic beta-kallikrein-B by 4',6-diamidino-2-phenylindole, 6-amidinoindole and benzamidine: a comparative thermodynamic and X-ray structural study

The inhibitory effect of 4',6-diamidino-2-phenylindole (DAPI) and 6-amidinoindole on the catalytic properties of bovine beta-trypsin (trypsin), human alpha-thrombin (thrombin) and porcine pancreatic beta-kallikrein-B (kallikrein) was investigated (between pH 3.0 and 7.0, I = 0.1 M; T = 30.0 +/- 0.5 degrees C), and analyzed in parallel with that of benzamidine, commonly taken as a molecular inhibitor model of serine proteinases. Next, the X-ray crystal structure of the trypsin:DAPI complex was solved at 1.9 A resolution (R = 0.161). Over the whole pH range explored, values of the association inhibition constant (Ki) for DAPI and 6-amidinoindole binding to trypsin, thrombin and kallikrein are higher than those found for benzamidine association, suggesting a binding mode of DAPI to the enzyme primary specificity pocket-based on the indole moiety of the inhibitor. On lowering the pH from 5.5 to 3.0, the decrease in affinity for DAPI, 6-amidinoindole and benzamidine binding to trypsin, thrombin and kallikrein reflects the acidic pK shift of the Asp189 invariant residue, present at the bottom of the primary specificity subsite of the serine proteinases considered, from 4.5, in the free enzyme, to 3.7, in the proteinase:inhibitor complexes. Inspection of the refined crystal structure of the trypsin:DAPI complex, however, does not allow a unique interpretation of the inhibitor binding mode. The present data were analysed in parallel with those reported for related serine (pro)enzyme/inhibitor systems.

29-Methylidene-2,3-oxidosqualene derivatives as stereospecific mechanism-based inhibitors of liver and yeast oxidosqualene cyclase

Two pairs of isomers (18Z)- (8), (18E)-29-methylidene-2,3-oxidohexanorsqualene (21), and (18Z)- (31), (18E)-29-methylidene-2,3-oxidosqualene (34), have been obtained in a fully stereospecific manner, as inhibitors of rat and yeast oxidosqualene cyclase. A new method for the synthesis of C22 squalene aldehyde 2,3-epoxide is reported, as well as that of other 19-modified 2,3-oxidosqualene analogues. We found that the activity is the opposite in the two series: the (E)-hexanormethylidene 21 and the (Z)-methylidene 31 are potent and irreversible inhibitors of oxidosqualene cyclase, while (Z)-hexanormethylidene 8 and (E)-methylidene 34 are almost completely inactive. Reduction of the 18,19-double bond, such as in 39, eliminates the activity, while removal of both of the 19-linked groups such as in heptanor derivative 40 greatly reduces inhibition of the enzyme. (E)-Hexanormethylidene 21 results the first irreversible inhibitor of the series toward the yeast enzyme.

Inhibition of 2,3-oxidosqualene cyclase and sterol biosynthesis by 10- and 19-azasqualene derivatives

The inhibition of 2,3-oxidosqualene-lanosterol cyclase (EC 5.4.99.7) (OSC) by new azasqualene derivatives, mimicking the proC-8 and proC-20 carbocationic high-energy intermediates of the cyclization of 2,3-oxidosqualene to lanosterol, was studied using pig liver microsomes, partially purified preparations of OSC, and yeast microsomes. The azasqualene derivatives tested were: 6E- and 6Z-10aza-10,11-dihydrosqualene-2,3-epoxide 17 and 18, 19-aza-18,19,22,23-tetrahydrosqualene-2,3-epoxide 19 and its corresponding N-oxide 20, and 19-aza-18,19,22,23-tetrahydrosqualene 21. The compounds 17 and 19 (i.e. the derivatives bearing the 2,3-epoxide ring and the same geometrical configuration as the OSC substrate) were effective inhibitors, as shown by the Ki obtained using partially purified OSC: 2.67 microM and 2.14 microM, respectively. Compound 18, having an incorrect configuration and the 19-aza derivative 21, lacking the 2,3-epoxide ring, were poor inhibitors, with IC50 of 44 microM and 70 microM, respectively. Compound 21 was a competitive inhibitor of OSC, whereas 17 and 19 were noncompetitive inhibitors, and showed a biphasic time-dependent inactivation of OSC, their apparent binding constants being 250 microM and 213 microM, respectively. The inhibition of sterol biosynthesis was studied using human hepatoma HepG2 cells. The incorporation of [14C] acetate in the C27 sterols was reduced by 50% by 0.55 microM 17, 0.22 microM 19, and 0.45 microM 21, whereas 2 microM 18 did not affect sterol biosynthesis. In the presence of 17, 19 and 21, only the intermediate metabolites 2,3-oxidosqualene and 2,3,22,23-dioxidosqualene accumulated, demonstrating a very specific inhibition of OSC.

Infliximab for pediatric ulcerative colitis: a retrospective Italian multicenter study

BACKGROUND

Infliximab (IFX), the chimeric anti TNFalpha antibody, an established treatment for Crohn's disease in adults and in children, is used less frequently in ulcerative colitis (UC).

AIM OF THE STUDY

To report the clinical course of pediatric patients with active UC receiving IFX.

PATIENTS AND METHODS

Charts of 22 patients were reviewed (13 male, 9 female): 4 with a severe UC attack refractory to systemic corticosteroids (CS); 18 with a protracted course, of which 16 CS-dependent and 2 CS-resistant. The baseline therapeutic program consisted of 3 consecutive intravenous infusions (0, 2, 6 weeks) of IFX (5 mg/kg), followed by a retreatment schedule (infusion every 8 weeks); azathioprine (AZA) was administered chronically in all. Clinical evaluation was done with the Lichtiger Colitis Activity Index (LCAI). Follow-up was performed until week 54. LCAI >/= 9 was considered treatment failure; a LCAI

RESULTS

All 22 patients began the study with a LCAI > 9: 12 had a full response and were on remission at week 54 and did not receive CS (8 on IFX re-treatment and AZA, 4 on AZA alone); 6 had a partial response; 4 were non responders. Colectomy was performed in 7 patients, beyond the period of the acute attack in all but one.

CONCLUSIONS

In children with severe ulcerative colitis IFX is a valuable treatment for inducing remission, avoiding emergency colectomy; retreatment may be offered to maintain remission.

Collapse

Key Words Collapse

MESH Headings

• Adolescent
• Antibodies, Monoclonal/therapeutic use
• Azathioprine/therapeutic use
• Child
• Colitis, Ulcerative/drug therapy
• Drug Therapy, Combination
• Female
• Humans
• Immunosuppressive Agents/therapeutic use
• Infliximab
• Italy
• Male
• Remission Induction
• Retrospective Studies
• Salvage Therapy

Collapse

Grants Collapse

2,3-Oxidosqualene cyclase: from azasqualenes to new site-directed inhibitors

2,3-Oxidosqualene cyclases (OSC) are enzymes which convert 2,3-oxidosqualene (OS) into polycyclic triterpenoids such as lanosterol, cycloartenol, and alpha- and beta-amyrin. Our interest in the study of OSC is the development of new OSC inhibitors for potential use as hypocholesterolemic, antifungal, or phytotoxic drugs. In particular, we describe the biological activity and the mechanism of a series of acyclic azasqualene derivatives mimicking the C-2, C-8, and C-20 carbonium ions formed during OS cyclization. Some of these carbonium ion analogues are very promising as specific hypocholesterolemic agents. The toxicity, the biodistribution, and the pharmacokinetics of different azasqualene derivatives in mice are also presented. In order to obtain new, site-directed irreversible inhibitors of OSC, a series of squalene derivatives containing functional groups that can link covalently to an active-site thiol group was designed. Among these compounds, squalene maleimide was the most active toward mammalian OSC, whereas squalene Ellman behaved as an irreversible inhibitor of OSC from yeast.

Carnitine deficiency in patients with coeliac disease and idiopathic dilated cardiomyopathy

BACKGROUND AND AIMS

Idiopathic dilated cardiomyopathy (IDCM) and coeliac disease (CD) are two pathological conditions which may lead, by different mechanisms, to malabsorption of various micronutrients, including carnitine, active in cardiac metabolism. The aim of the present investigation was primarily to evaluate differences in serum concentrations of total carnitine between IDCM patients and patients with IDCM associated with CD and then also to evaluate, in the latter, the effect of a gluten-free diet on serum concentrations of total carnitine.

METHOD AND RESULTS

Serum carnitine was determined by enzymatic spectrophotometric assay in three groups of individuals: group A, 10 patients (5 males, 5 females), mean age 46.5+/-10.8 years, presenting isolated IDCM; group B, 3 patients (2 males, 1 female), mean age 34+/-8 years, with IDCM+CD; and group C, 10 healthy subjects (5 males, 5 females), mean age 38.6+/-11.1 years. All patients with IDCM belonged to class NYHA I-II. Mean concentrations of total serum carnitine in the group of patients with isolated IDCM (group A) were found to be lower than in the controls (group C). The concentrations in patients with IDCM associated with CD (group B) were lower than in the control group and also lower than in the isolated IDCM (group A). After 2 years on a gluten-free diet, patients presenting IDCM associated with CD showed a progressive increase in mean serum carnitine levels compared to values observed prior to the diet.

CONCLUSIONS

Patients presenting IDCM associated with CD show a greater decrease in serum total carnitine levels than patients presenting the isolated form of IDCM. A gluten-free diet, in these patients, leads to a progressive increase in serum levels of this substance.

Floating Gate, Organic Field-Effect Transistor-Based Sensors towards Biomedical Applications Fabricated with Large-Area Processes over Flexible Substrates

Organic Field-Effect Transistors (OFETs) are attracting a rising interest for the development of novel kinds of sensing platforms. In this paper, we report about a peculiar sensor device structure, namely Organic Charge-Modulated Field-Effect Transistor (OCMFET), capable of operating at low voltages and entirely fabricated with large-area techniques, i.e., inkjet printing and chemical vapor deposition, that can be easily upscaled to an industrial size. Device fabrication is described, and statistical characterization of the basic electronic parameters is reported. As an effective benchmark for the application of large-area fabricated OCMFET to the biomedical field, its combination with pyroelectric materials and compressible capacitors is discussed, in order to employ the proposed device as a temperature pressure sensor. The obtained sensors are capable to operate in conditions which are relevant in the biomedical field (temperature in the range of 18.5-50 °C, pressure in the range of 10²-10³ Pa) with reproducible and valuable performances, opening the way for the fabrication of low-cost, flexible sensing platforms.

A sub-150-nanometre-thick and ultraconformable solution-processed all-organic transistor

Recent advancements in the field of electronics have paved the way to the development of new applications, such as tattoo electronics, where the employment of ultraconformable devices is required, typically achievable with a significant reduction in their total thickness. Organic materials can be considered enablers, owing to the possibility of depositing films with thicknesses at the nanometric scale, even from solution. However, available processes do not allow obtaining devices with thicknesses below hundreds of nanometres, thus setting a limit. Here, we show an all-organic field effect transistor that is less than 150 nm thick and that is fabricated through a fully solution-based approach. Such unprecedented thickness permits the device to conformally adhere onto nonplanar surfaces, such as human skin, and to be bent to a radius lower than 1 μm, thereby overcoming another limitation for field-effect transistors and representing a fundamental advancement in the field of ultrathin and tattoo electronics.