Burden of celiac disease in the Mediterranean area

AIM: To estimate the burden of undiagnosed celiac disease (CD) in the Mediterranean area in terms of morbidity, mortality and health cost. METHODS: For statistics regarding the population of each country in the Mediterranean area, we accessed authoritative international sources (World Bank, World Health Organization and United Nations). The prevalence of CD was obtained for most countries from published reports. An overall prevalence rate of 1% cases/total population was finally estimated to represent the f...     

Porphyromonas gingivalis cysteine proteinase inhibition by kappa-casein peptides

Porphyromonas gingivalis is a major pathogen associated with chronic periodontitis, an inflammatory disease of the supporting tissues of the teeth. The Arg-specific (RgpA/B) and Lys-specific (Kgp) cysteine proteinases of P. gingivalis are major virulence factors for the bacterium. In this study κ-casein(109-137) was identified in a chymosin digest of casein as an inhibiting peptide of the P. gingivalis proteinases. The peptide was synthesized and shown to inhibit proteolytic activity associated with P. gingivalis whole cells, purified RgpA-Kgp proteinase-adhesin complexes, and purified RgpB proteinase. The peptide κ-casein(109-137) exhibited synergism with Zn(II) against both Arg- and Lys-specific proteinases. The active region for inhibition was identified as κ-casein(117-137) using synthetic peptides. Kinetic studies revealed that κ-casein(109-137) inhibits in an uncompetitive manner. A molecular model based on the uncompetitive action and its synergistic ability with Zn(II) was developed to explain the mechanism of inhibition. Preincubation of P. gingivalis with κ-casein(109-137) significantly reduced lesion development in a murine model of infection.     

Platelets from children are hyper‐responsive to activation by thrombin receptor activator peptide and adenosine diphosphate compared to platelets from adults

Platelets are crucial subcellular elements of haemostasis at sites of vascular injury and are also known to be immune mediators in pathological thrombosis. Despite the integral role of platelets in many disease processes, there is very little information available on platelet function and response to agonists in healthy children. We recently reported important differences in the interaction of platelets with monocytes in the circulation, including increased formation of monocyte‐platelet aggregates (MPAs) without concomitant increase in P‐selectin expression. Our current study investigates parameters of platelet activation (PAC‐1 binding and P‐selectin expression) and MPA formation in response to a range of physiologically relevant platelet agonists in healthy children compared to healthy adults. All parameters were significantly higher in children in response to sub‐maximal concentrations of thrombin receptor activator peptide and adenosine diphosphate, reflecting an age‐specific difference in agonist‐stimulated platelet reactivity in children. The results of our study challenge the general assumption that platelet reactivity in children is similar to adults. This finding is fundamental to investigating the role of platelets in diseases of childhood and pathogenesis of adult‐based diseases that have their origins in childhood. Our findings underscore the need for age‐specific reference ranges for platelet function in children rather than extrapolation from adult data.     

Activated factor X and thrombin formation triggered by tissue factor on endothelial cell matrix in a flow model: effect of the tissue factor pathway inhibitor

The procoagulant subcellular matrix of stimulated endothelial cells that contains tissue factor (TF) was used to investigate the mechanism by which TF pathway inhibitor (TFPI) inhibits thrombin formation initiated by TF/factor VIIa (FVIIa) under flow conditions. Purified coagulation factors VII, X, and V and prothrombin were perfused at a wall shear rate of 100 s-1 through a flow chamber containing a coverslip covered with matrix of cultured human umbilical vein endothelial cells. This resulted in a TF- and FVII-dependent FXa and thrombin generation as measured in the effluent at the outlet of the system. Inhibition of this TF/FVIIa-triggered thrombin formation by TFPI purified from plasma was dependent on the amount of TF present on the endothelial cell matrix. The rate of prothrombinase assembly and steady-state levels of thrombin formation were decreased by TFPI. Because persistent albeit decreased steady-state levels of thrombin formation occurred in the presence of TFPI, we conclude that plasma- TFPI does not inhibit FXa present in the prothrombinase complex. The addition of FIX and FVIII to perfusates containing FVII and FX increased the FXa generation on endothelial matrices, and counteracted the inhibition of thrombin formation on endothelial cell matrices by TFPI. Our data provide further evidence for the hypothesis that the rapid inactivation of TF/FVIIa by TFPI in combination with the absence of either FVIII or FIX causes the bleeding tendency of patients with hemophilia A or B.     

Disease-free survival after autologous bone marrow transplantation in patients with acute myelogenous leukemia

Autologous bone marrow transplantation (ABMT) makes it possible to escalate the dose of cytotoxic treatment to a lethal range. Disease- free survival (DFS) following myeloablative therapy and ABMT has been shown to be superior to conventional treatment in high risk patients with acute myelogenous leukemia (AML). It was the purpose of the present study to compare hematopoietic reconstitution, actuarial DFS, and relapse rate of patients transplanted in first complete remission (CR) of AML with those in second or subsequent CR, and to evaluate transplant related mortality. Fifty-two patients with AML, 22 in first CR (low risk) and 30 in second or subsequent CR (high risk), underwent total body irradiation (12.1 to 16.7 Gy) and cyclophosphamide (CY) treatment (200 mg/kg) followed by ABMT. The autograft was incubated with the active CY derivative Mafosfamide (ASTA Werke, Bielefeld, Federal Republic of Germany) to reduce the number of possibly contaminating clonogenic tumor cells. All patients showed three lineage engraftments with platelet recovery observed as being the slowest. The transplant related death rate was low at 5.8%. There was no significant difference in the kinetics of polymorphonuclear (PMN) cell or platelet reconstitution between the low and high risk patient subgroups. The estimated probability of DFS (relapse) after ABMT in first CR was 61% (36%) compared with 34% (65%) in second or subsequent CR, the longest follow-up being 55 months and 57 months, respectively (median follow-up 31 months and 19 months, respectively). ABMT offers a stable long-term DFS when performed in first CR with no relapses occurring in over a year after transplantation. Six later relapses, however, were seen after ABMT in second or subsequent CR, although DFS was not statistically different from that of first remission patients (P = .72).     

Esophageal polyps in pediatric patients undergoing routine diagnostic upper gastrointestinal endoscopy: a multicenter study

Esophageal polyps are uncommon findings in pediatric patients, and reports have been limited to case reports. Esophageal polyps have been previously ascribed to esophagitis secondary to gastroesophageal reflux, medications, infections and recurrent vomiting. They have been associated with underlying conditions such as hiatal hernia, Barrett's esophagus, eosinophilic esophagitis and Crohn's disease. Presenting complaints of children with esophageal polyps have included vomiting, dysphagia, hematemesis and abdominal pain. The aim of this paper is to characterize the incidence, clinical presentation and progression, histologic subtypes and associated mucosal abnormalities in children with esophageal polyps. A retrospective multicenter study was performed at four institutions identifying diagnosis of esophageal polyps in pediatric patients (<21 years). Information was obtained from patient charts, endoscopy reports and histopathology reports. Specimens and slides were examined by experienced pediatric pathologists for all included cases. Esophageal polyps were identified in 13 patients (9 M) from 9438 esophagogastroduodenoscopies (0.14%). Mean age of subjects was 9.2 years. Vomiting was the most common indication for endoscopy. Polyp location was at the gastroesophageal junction in 7 of the 13 cases. Most polyps were inflammatory (n = 7). Esophagitis was noted in 69% of those with esophageal polyps. Repeat endoscopies in six patients at a mean interval of 8 months noted persistence of polyps in all six patients. This paper is the first to characterize esophageal polyps in pediatrics. These polyps are rare in children and often are associated with esophagitis. Presenting complaints seem to vary by age. Polyps did not consistently change with either time or acid suppression. The optimal management strategy has yet to be defined and likely depends on the underlying pathophysiologic process.     

Phase II trial of 2-chlorodeoxyadenosine for the treatment of cutaneous T-cell lymphoma [see comments]

We investigated the efficacy of 2-chlorodeoxyadenosine (2-CdA) therapy in patients with mycosis fungoides (MF) and the Sezary syndrome (SS). Between February 1991 and November 1993, 21 patients with relapsed or refractory MF/SS were treated with 2-CdA. 2-CdA was administered by continuous intravenous infusion at a dose of 0.1 mg/kg/d for 7 days initially (13 patients), but was subsequently reduced to 5 days (nine patients) due to hematologic toxicity. All patients had failed to respond to at least one prior treatment for MF/SS (median number of total prior therapies, five; median number of systemic prior therapies, three) and had an Eastern Cooperative Oncology Group performance status of two or better. Cycles were administered at 28-day intervals. Assessable patients received at least 5 days of 2-CdA. Fourteen patients received more than one cycle of 2-CdA. An overall response rate of 28% was achieved. Three patients (14%) had a complete response with a median duration of 4.5 months (range, 2.5 to 16). Three (14%) had a partial response with a median duration of 2 months (range, 2 to 4). Fifteen patients (72%) had no response. The most significant toxicities encountered were bone marrow suppression (62% of patients) and infectious complications (62% of patients). Thirty-eight percent of patients experienced no toxicity from 2-CdA. 2-CdA has activity as a single agent in patients with previously treated relapsed MF/SS. Studies in less heavily pretreated individuals with 2-CdA alone or in combination will be undertaken.     

Molecular basis of the heterogeneity of expression of glycosyl phosphatidylinositol anchored proteins in paroxysmal nocturnal hemoglobinuria

The purpose of these studies was to determine the molecular basis of the phenotypic mosaicism that is a defining feature of paroxysmal nocturnal hemoglobinuria (PNH). Analysis of T cell clones from a female patient revealed four distinct phenotypes based on surface expression of glycosyl phosphatidylinositol-anchored proteins (GPI-AP). When PIG-A (the gene that is mutant in PNH) from these clones was analyzed, four discrete somatic mutations were identified. Analysis of X chromosomal inactivation among the abnormal T cell clones was consistent with polyclonality. Together, these studies demonstrate that the phenotypic mosaicism that is characteristic of PNH is a consequence of genotypic mosaicism and that, at least in this case, PNH is a polyclonal rather than a monoclonal disease. That four distinct somatic mutations were present in a single patient suggests that in conditions that predispose to PNH PIG-A may be hypermutable.