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We present a set of low-frequency electrical conductivity measurements of solutions of differently charged, salt-free polyelectrolytes in poor- and in good-solvent conditions, in the semidilute concentration regime. The data have been analyzed and discussed in light of the necklace model for hydrophobic polyelectrolytes recently proposed by Dobrynin et al. [Macromolecules 29, 2974 (1996)] that predicts the chains to collapse into spheroidal cores connected by narrow strings. By varying the quality of the solvent, we have measured the polyion equivalent conductance λp in an extended concentration range in the semidilute regime and have demonstrated that this parameter is influenced by the polyion chain conformation, giving further support, when the poor-solvent condition prevails, to the picture of a string of electrostatic blobs. On the contrary, in good-solvent condition, the electrical conductivity data are in reasonable good agreement with the picture of an extended chain consisting of a collection of electrostatic blobs. These electrical conductivity measurements, in light of scaling theory, furnish new experimental support for the necklace model for hydrophobic polyions in poor solvents. [ABSTRACT FROM AUTHOR]

The effect of a cationic lipid [DOTAP] on both the thermotropic phase behavior and the structural organization of aqueous dispersions of dipalmitoyl-phosphatidylcholine [DPPC] is examined by using high-sensitivity differential scanning calorimetry and dynamic light scattering measurements. The self-assembling restructuring from an aqueous multilamellar structure toward a liposomal phase can be obtained by decreasing the phospholipid phase transition temperature and by increasing the temperature of the system.

Background Bullous pemphigoid (BP) is an autoimmune skin disease in which patient autoantibodies react with BP180 and BP230 proteins. In addition to IgG, IgE has been shown to play a role in the disease. Objectives To evaluate the feasibility of detecting IgE and IgG against the immunodominant BP180 NC16A domain (BP180) using a microarray system. Methods BP180 was immobilized on an experimental version of the ISAC® microarray (Exp96). The BP study group and the controls were all tested on the commercial ISAC 103 version and on the Exp96. IgG and IgE were measured in a single run. BP180 IgG and IgE results were compared with those using an enzyme-linked immunosorbent assay (ELISA). Results All results obtained using the IgG ELISA on the 31 patients with BP were replicated with the ISAC IgG. Five of eight BP sera tested by ELISA showed similar results with ISAC IgE. Twenty-nine (94%) and 19 (61%) of the 31 patients with BP were IgG and IgE positive to BP180, respectively, whereas four (3%) and six (4%) of 138 normal donors were IgG and IgE positive, respectively. Interestingly, the levels of IgG against BP180 detected using the ISAC system were related to the disease severity. Patients with BP showed a peculiar profile of IgE recognition toward some groups of allergens, which was absent in a group of allergic individuals. A significant, higher prevalence of hen's egg recognition was observed in patients with BP who had specific IgE to BP180. Conclusions The present preliminary study indicates that the ISAC microarray system is suitable for detecting IgG and IgE autoantibodies in patients with BP. Notably, this system allows the assessment of IgE and IgG autoantibodies at the same time, could be employed for the detection of autoantibodies to other autoantigens, and allows profiling for specific IgE to allergens. [ABSTRACT FROM AUTHOR]

Allergic reactions caused by 9kDa Lipid Transfer Proteins (9k-LTP), such as Pru p 3, have been widely investigated, whereas a possible contribution of components of 7kDa LTP (7k-LTP) sub-family in triggering allergic symptoms has been overlooked so far. With the aim to investigate the contribution of 7k-LTPs to the food allergies, we have identified, isolated and characterised a tomato seed 7k-LTP (Sola l 7k-LTP). The protein was purified by chromatographic separations, identified by direct protein sequencing and mass spectrometry and a molecular model was built. Functional evaluation of the allergen has been performed by skin testing. Sola l 7k-LTP consists of 68 amino acids producing a molecular mass of 7045Da and displays 41% sequence identity with Pru p 3, the allergenic 9k-LTP from peach. IgE antibodies specifically recognising Sola l 7k-LTP were found within the population claiming tomato ingestion-related symptoms, but also in subjects tolerant on tomato exposure. A few subjects were mono-sensitised to Sola l 7k-LTP, which is biologically active as shown by the positive skin test. In line with the immunological results, the molecular model shows structural similarities between the IgE binding regions of the two sub-families. Therefore, Sola l 7k-LTP shares some structural and immunological features with Pru p 3, but it also displays individual features that could be responsible for mono-specific IgE binding. In conclusion, Sola l 7k-LTP is a new identified allergenic LTP, the description of which may contribute to the improvement of allergy diagnosis and to the formulation of a safe and personalised diet. In addition, to avoid current confusing classifications, a new nomenclature policy for LTP sub-families is proposed in this paper. We now suggest that 7-kDa LTP (so far named LTP2) be renamed 7k-LTP and 9-kDa LTP (so far named LTP1) be renamed 9k-LTP., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Kiwellin (Act d 5) is an allergenic protein contained in kiwifruit pulp in high amounts. The aim of this study was to investigate the three-dimensional structure of the natural molecule from green kiwifruit and its possible function. Kiwellin was crystallized, and its structure, including post-translational modifications, was elucidated. The molecular weight and structural features, in solution, were analyzed by gel filtration and circular dichroism, respectively. Although structurally similar to expansin, kiwellin lacks expansin activity and carbohydrate binding. A specific algorithm was applied to investigate any possible IgE reactivity correlation between kiwellin and a panel of 102 allergens, including expansins and other carbohydrate-binding allergens. The available data suggest a strong dependence of the kiwellin structure on the environmental/experimental conditions. This dependence therefore poses challenges in detecting the correlations between structural, functional, and immunological features of this protein.

Background & Aims: Therapeutic antibodies against tumor necrosis factor α (anti-TNF) are effective in patients with Crohn's disease (CD). Mucosal healing is a surrogate marker of efficacy, but little is known about the effects of anti-TNF agents on structural damage in the intestine. Small-intestine contrast ultrasonography (SICUS) is a valuable tool for assessing CD lesions. A new sonographic quantitative index (the sonographic lesion index for CD [SLIC]) was developed to quantify changes in CD lesions detected by SICUS. We explored whether the SLIC can be used to monitor transmural bowel damage in CD patients during anti-TNF therapy., Methods: We performed a prospective study of 29 patients with ileal or ileocolonic CD treated with anti-TNF agents; patients underwent SICUS before and after scheduled induction and maintenance therapy. To determine whether changes that can be detected by SICUS occur independently of anti-TNF therapy, 7 patients with ileal CD treated with mesalamine were enrolled as controls. A clinical response was defined as steroid-free remission, with CD activity index scores less than 150., Results: We observed significant improvements in SLIC scores and subscores after induction and maintenance therapy with anti-TNFs, compared with before therapy. SLIC scores and subscores and index classes were improved significantly in patients with vs without clinical responses. Controls had no improvements in terms of CD activity index or SLIC scores, or index classes., Conclusions: Sonographic assessment using the quantitative index SLIC can be used to monitor changes in transmural bowel damage during anti-TNF therapy for CD., (Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.)

A comparative analysis of three different estimation methods of cocaine use in Milan, Italy, is carried out, including an analysis of the size and trends of the underlying reference population. The three cocaine use estimates are derived from wastewater analysis, a "street" survey and one-source capture-recapture analysis of administrative sanctions for drug possession. All three data sources span several years during the decade 2000-2010. For each method, assumptions and limitations are discussed. It is concluded, although the amount of data regarding cocaine use in Milan during the years 2000-2010 is considerable, that none of the estimates is completely reliable, mainly because of the many assumptions needed for inference to the whole community, that all three estimates however agree on a substantial reduction in cocaine use and users between the years 2007 and 2010. The recently developed wastewater analysis technique yields estimates comparable to those derived from the street based survey, while capture-recapture analysis of administrative data on identification by law enforcement agencies as cocaine user probably targets only a subpopulation of all users.

Small intestine contrast ultrasonography (SICUS) has emerged as a valuable tool in the detection of intestinal damage in Crohn's disease (CD). Our aim was to develop a numerical index quantitating small bowel damage as detected by SICUS in patients with an established diagnosis of CD. One hundred and ten patients with ileal or ileocolonic CD were prospectively enrolled and followed up for one year. Disease activity was assessed by CDAI and CRP levels. Study variables included bowel wall thickness, lumen diameter, lesion length and number of lesion site. Fistula, mesenteric adipose tissue alteration, abscess and lymphnodes were also considered. Bowel segments were considered as a hollow cylinder. Standardized variations of variables were combined into a statistical and mathematical model to create an algorithm scoring an index value ranging from 0 to 200. Index was subdivided into a severity scale with 5 classes from the lower (A) to the higher score (E). Median lesion index value was significantly higher (p<0.005) in patients with a CDAI>150 and in patients with CRP>5 mg/l (p=0.003). Patients classified in class E and D at SICUS underwent surgery within one year follow up more frequently than those in class C, B and A (p<0.0001). We propose a new index for assessment of small bowel lesions in CD (SLIC: sonographic lesion index for CD) developed by using SICUS. This index may turn ultrasonography in CD from a descriptive qualitative assessment to a quantitative numerical index suitable for comparison studies., (Copyright © 2012 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.)

Background & Aims: The combined role of immunomodulators (IMM) and clinical characteristics of Inflammatory Bowel Disease (IBD) in determining the cancer risk is undefined. The aim was to assess whether clinical characteristics of IBD are independent risk factors for cancer, when considering thiopurines and anti-TNFs use., Methods: In a single-center cohort study, clinical characteristics of IBD patients with IBD duration ≥1 year and ≥2 visits from 2000 to 2009 were considered. Tests for crude rates and survival analysis methods were used to assess differences of incidence of cancer between groups. The methods were adjusted for the time interval between diagnosis and immunomodulatory treatments., Results: IBD population included 1222 patients :615 Crohn's disease (CD), 607 ulcerative colitis (UC). Cancer was diagnosed in 51 patients (34 CD,17 UC), with an incidence rate of 4.3/1000 pt/year. The incidence rate of cancer was comparable between CD and UC (4.6/1000 pt/year vs 2.9/1000 pt/year ;p=n.s.). Cancer most frequently involved the breast, the GI tract, the skin. Lymphoma was diagnosed in CD (1HL, 1NHL,0 HSTCL). Risk factors for cancer included older age at diagnosis of IBD (CD: HR 1.25;95%CI 1.08-1.45; UC:HR 1.33;95%CI 1.15-1.55 for an increase by 5 years; p=0.0023; p=0.0002), fistulizing pattern in CD (HR 2.55; 95%CI 1.11-5.86,p=0.0275), pancolitis in UC (HR 2.79;95%CI 1.05-7.40 p=0.0396 vs distal). IMM and anti-TNFs did not increase the cancer risk in CD, neither IMM in UC (anti-TNFs risk in UC not feasible as no cases observed)., Conclusions: Fistulizing pattern in CD, pancolitis in UC and older age at diagnosis of IBD are independent risk factors for cancer., (Copyright © 2011 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.)

Background: From patients' reports and our preliminary observations, a fully maturated cheese (Parmigiano-Reggiano; PR) seems to be well tolerated by a subset of cow's milk (CM) allergic patients., Objective and Methods: To biochemically and immunologically characterize PR samples at different maturation stage and to verify PR tolerability in CM allergic children. Seventy patients, with suspected CM allergy, were enrolled. IgE to CM, α-lactalbumin (ALA), β-lactoglobulin (BLG) and caseins (CAS) were tested using ImmunoCAP, ISAC103 and skin prick test. Patients underwent a double-blind, placebo-controlled food challenge with CM, and an open food challenge with 36 months-maturated PR. Extracts obtained from PR samples were biochemically analyzed in order to determine protein and peptide contents. Pepsin and trypsin-chymotrypsin-pepsin simulated digestions were applied to PR extracts. Each PR extract was investigated by IgE Single Point Highest Inhibition Achievable assay (SPHIAa). The efficiency analysis was carried out using CM and PR oral challenges as gold standards., Results: The IgE binding to milk allergens was 100% inhibited by almost all PR preparations; the only difference was for CAS, mainly α(S1)-CAS. Sixteen patients sensitized to CM tolerated both CM and PR; 29 patients tolerated PR only; 21 patients, reacted to both CM and PR, whereas 4 patients reactive to CM refused to ingest PR. ROC analysis showed that the absence of IgE to BLG measured by ISAC could be a good marker of PR tolerance. The SPHIAa using digested PR preparations showed a marked effect on IgE binding to CAS and almost none on ALA and BLG., Conclusions: 58% of patients clinically reactive to CM tolerated fully maturated PR. The preliminary digestion of CAS induced by PR maturation process, facilitating a further loss of allergenic reactivity during gut digestion, might explain the tolerance. This hypothesis seems to work when no IgE sensitization to ISAC BLG is detected.

Background & Aims: The diagnostic role of Small Bowel Capsule Endoscopy (SBCE) in Crohn's Disease (CD) is under investigation. In a prospective study we investigated the diagnostic role of SBCE in patients with symptoms highly compatible with CD and undefined diagnosis after conventional techniques., Methods: From September 2005 to May 2009, all patients with clinically suspected CD and not conclusive diagnosis after Ileocolonoscopy (IC), Small Bowel Follow Through (SBFT) and Small Intestine Contrast Ultrasonography (SICUS) were enrolled. Findings compatible with CD included: bowel wall thickness (BWT) >3mm (for SICUS), ulcers, stenosis/strictures, fistulae (for SICUS, SBFT); >5 aphtoid ulcers, deep ulcers and/or strictures (for SBCE)., Results: Conventional techniques did not lead to a conclusive diagnosis in 30 patients (19 F, median age 31 years, range 8-57), showing chronic diarrhoea (n=27), abdominal pain (n=23), weight loss (n=5), fever (n=5), Iron Deficiency Anaemia (IDA)(n=5) and/or perianal disease (n=4). Findings compatible but not diagnostic for small bowel CD were detected in 19 (63%) by IC in 12 (40%) by SICUS and in 15 (50%) by SBFT. SBCE showed ileal lesions in 15 (50%) patients, including findings compatible with CD in 12 (40%). SBCE retention requiring surgery was observed in 1 patient. A significant concordance was observed between SBCE and IC k=0.33 C(k)=[0.25;0.42], but not between SBCE and SICUS k=0.13 IC(k)=[0.045;0.22] and between SBCE and SBFT k=0 IC(k)=[-0.089;0.089]., Conclusions: SBCE may detect lesions compatible with small bowel CD in almost one third of patients with symptoms highly compatible with CD and not conclusive diagnosis by using conventional techniques., (Copyright © 2010 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.)