Priming effect in children with Type 1 Diabetes Mellitus

Previous studies have evidenced cognitive difficulties across various domains in Type 1 Diabetes Mellitus (T1DM) children, but the implicit memory system has not yet been systematically explored.Taking into account that the interplay between memory and perception may be modulated by the semantic category of the stimuli and their salience, we explored explicit and implicit memory using both object and food stimuli to verify whether for T1DM children there is a feebleness in performing the function of memory as a function of the stimuli used.Eighteen T1DM children and 47 healthy children performed an explicit recognition task in which they were requested to judge whether the presented image had already been shown ("old") or not ("new") and an identification priming task in which they were asked to name new and old pictures presented at nine ascending levels of spatial filtering.Results did not reveal any differences between controls and T1DM children in the explicit memory recognition task, whereas some differences between the two groups were found in the identification priming task. In T1DM children, the priming effect was observed only for food images.The dissociation between implicit and explicit memory observed in children with diabetes seems to be modulated by the category of the stimuli, and these results underscore the relevance of taking into account this variable when exploring cognitive functions.

Automatic and controlled attentional orienting in the elderly: A dual-process view of the positivity effect

The positivity effect in the elderly consists of an attentional preference for positive information as well as avoidance of negative information. Extant theories predict either that the positivity effect depends on controlled attentional processes (socio-emotional selectivity theory), or on an automatic gating selection mechanism (dynamic integration theory). This study examined the role of automatic and controlled attention in the positivity effect. Two dot-probe tasks (with the duration of the stimuli lasting 100 ms and 500 ms, respectively) were employed to compare the attentional bias of 35 elderly people to that of 35 young adults. The stimuli used were expressive faces displaying neutral, disgusted, fearful, and happy expressions. In comparison to young people, the elderly allocated more attention to happy faces at 100 ms and they tended to avoid fearful faces at 500 ms. The findings are not predicted by either theory taken alone, but support the hypothesis that the positivity effect in the elderly is driven by two different processes: an automatic attention bias toward positive stimuli, and a controlled mechanism that diverts attention away from negative stimuli.

Stress and brain functional changes in patients with Crohn's disease: A functional magnetic resonance imaging study

BACKGROUND

In Crohn's disease (CD) patients, stress is believed to influence symptoms generation. Stress may act via central nervous system pathways to affect visceral sensitivity and motility thus exacerbating gastrointestinal symptoms. The neural substrate underpinning these mechanisms needs to be investigated in CD. We conducted an explorative functional magnetic resonance imaging (fMRI) study in order to investigate potential differences in the brain stress response in CD patients compared to controls.

METHODS

17 CD patients and 17 healthy controls underwent a fMRI scan while performing a stressful task consisting in a Stroop color-word interference task designed to induce mental stress in the fMRI environment.

KEY RESULTS

Compared to controls, in CD patients the stress task elicited greater blood oxygen level dependent (BOLD) signals in the midcingulate cortex (MCC).

CONCLUSIONS & INFERENCES

The MCC integrate "high" emotional processes with afferent sensory information ascending from the gut. In light of these integrative functions, the stress-evoked MCC hyperactivity in CD patients might represent a plausible neural substrate for the association between stress and symptomatic disease. The MCC dysfunction might be involved in mechanisms of central disinhibition of nociceptive inputs leading to amplify the visceral sensitivity. Finally, the stress-evoked MCC hyperactivity might affect the regulation of intestinal motility resulting in exacerbation of disease symptoms and the autonomic and neuroendocrine regulation of inflammation resulting in enhanced inflammatory activity.

Prevalence of Fasciola hepatica in Galba truncatula detected by Multiplex PCR in the province of El Tarf (Algeria)

The prevalence of Fasciola hepatica infection in the snail Galba truncatula was studied for the first time in Algeria using Multiplex PCR. A total of 722 individuals were collected from 11 typical habitats (temporary ponds, road ditches and puddles) distributed in five localities of the El Tarf province, known for endemicity of fascioliasis. Snails were divided in 75 groups and DNA extraction was performed using Chelex® (Biorad, Nazareth Eke). Two primers were used, the first is specific for 124 bp DNA fragment of Fasciola sp and the second one represents the ITS-2 lymnaeids sequence (500-600 bp). The prevalence of the infection was estimated to be 46.66% for pools (35/75 were positive). The bursting out of the pools show that 75 snails were carriers of F. hepatica which gives an overall infection rate of about 10.74%. The results of snails infection according to their sizes showed significant differences in the studied size classes, thus snails of big sizes were the most infected. Based on these data, epidemiological implication of Multiplex PCR as a fully reliable technique to highlight high risks periods of fasciolosis will be of a great interest.

Molecular profiling of blastic plasmacytoid dendritic cell neoplasm reveals a unique pattern and suggests selective sensitivity to NF-kB pathway inhibition

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare disease of controversial origin recently recognized as a neoplasm deriving from plasmacytoid dendritic cells (pDCs). Nevertheless, it remains an orphan tumor with obscure biology and dismal prognosis. To better understand the pathobiology of BPDCN and discover new targets for effective therapies, the gene expression profile (GEP) of 25 BPDCN samples was analyzed and compared with that of pDCs, their postulated normal counterpart. Validation was performed by immunohistochemistry (IHC), whereas functional experiments were carried out ex vivo. For the first time at the molecular level, we definitely recognized the cellular derivation of BPDCN that proved to originate from the myeloid lineage and in particular, from resting pDCs. Furthermore, thanks to an integrated bioinformatic approach we discovered aberrant activation of the NF-kB pathway and suggested it as a novel therapeutic target. We tested the efficacy of anti-NF-kB-treatment on the BPDCN cell line CAL-1, and successfully demonstrated by GEP and IHC the molecular shutoff of the NF-kB pathway. In conclusion, we identified a molecular signature representative of the transcriptional abnormalities of BPDCN and developed a cellular model proposing a novel therapeutic approach in the setting of this otherwise incurable disease.

ARFI elastography in patients with chronic autoimmune liver diseases: A preliminary study

OBJECTIVE

Acoustic radiation force impulse (ARFI) is a new software-based technique that evaluates liver stiffness during B-mode ultrasonography. The purpose of this study was to evaluate the accuracy of ARFI in distinguishing patients with chronic autoimmune liver disease from healthy subjects.

MATERIAL AND METHODS

We enrolled 9 adult patients (8 women, 1 man; age 48.1 ± 12.8 years) with chronic autoimmune disease (primary biliary cirrhosis (PBC, n = 3), autoimmune hepatitis (AIH, n = 2), primary sclerosing cholangitis (PSC, n = 1) and overlap syndromes, (n = 3) who underwent a liver biopsy and 11 healthy volunteers (age 34.7 ± 10.4 years; 7 women, 4 men). Liver stiffness was evaluated and expressed as the shear wave velocity (SWV) in m/sec. We used a US scanner Siemens-Acuson S2000, evaluating the right liver lobe and the left liver lobe.

RESULTS

THE SWV WAS SIGNIFICANTLY HIGHER IN CASES (RIGHT LOBE: 1.51 ± 0.44; left lobe: 1.57 ± 0.40) than in controls (right lobe: 1.08 ± 0.10; left lobe: 1.12 ± 0.13) (right lobe: P = 0.002; left lobe: P = 0.013). We found no significant correlation between right and left lobe SWVs in cases (P = 0.779) or controls (P = 0.385). The SWV cut-off that best distinguished cases from controls was 1.25 m/sec (accuracy: AUC=0.885; sensitivity: 70.6%; specificity: 95.5%).

CONCLUSIONS

ARFI elastography is a noninvasive ultrasonographic technique that can differentiate healthy subjects from patients with fibrotic stages of chronic liver disease.

Real-time elastography as a noninvasive technique for quantification of fibrosis in patients with chronic viral liver disease: Preliminary findings

INTRODUCTION

Real-time elastography (RTE) is a novel technique for measuring tissue elasticity. The aims of this study were to prospectively measure liver stiffness with RTE in patients with chronic viral hepatitis and to evaluate the possible correlation between RTE data and the extent of fibrosis based on liver biopsy findings (Ishak score).

MATERIAL AND METHODS

Between February and October 2011, 26 patients (18M, 8F, mean age 41 ± 13 [standard deviation], range 22-62) with chronic viral hepatitis were prospectively evaluated with ultrasonography (US) that included RTE. All patients then underwent US-guided percutaneous liver biopsy (right lobe) for evaluation of fibrosis. Examinations were performed with a iU22 scanner (Philips, Bothell, WA, USA); a convex transducer (C5-1) was used for the US examination, and a linear transducer (L12-5) for RTE. In the RTE images, relative tissue stiffness is expressed according to a color scale with soft areas represented in green/red and hard areas in blue. Patients were examined in the supine position in suspended normal respiration; three loops of 20 RTE frames were recorded for each case. For each patient, we calculated the mean strain ratio (MSR) for the 3 loops. The Spearman correlation coefficient was used to assess correlation between the ASR and fibrosis stage (F) reflected by the Ishak score.

RESULTS

The Spearman coefficient showed significant correlation between the MSR and F (Rho = 0.470, p = 0.015).

CONCLUSIONS

RTE appears to be a useful tool for noninvasive evaluation of fibrosis in patients with chronic viral hepatitis although these findings need to be confirmed in larger case series.

Natural radioactivity in refractory manufacturing plants and exposure of workers to ionising radiation

This paper shows the results of a survey carried out at some refractory manufacturing plants. During the first part of the survey, the concentration of natural radioactivity in raw materials and end-products, coming from four plants, was assessed. Several raw materials and, as a consequence, some end-products as well have shown activity concentrations exceeding a few hundreds of Bq kg(-1) of (238)U and (232)Th. In some important raw materials, such as bauxite and corundums, a remarkable radioactive disequilibrium was observed; this is probably due to the high temperature processes undergone by these materials. The second part of the survey focussed on the measurements of ambient equivalent dose rates, airborne dust concentrations and radon indoor. On the basis of results obtained, the effective dose for the standard worker was estimated. Two different types of refractory plants were investigated. Effective doses for both plants were lower than 1 mSv y(-1).

Peripheral T cell lymphoma, not otherwise specified: the stuff of genes, dreams and therapies

Peripheral T cell lymphomas (PTCL) account for about 12% of lymphoid tumours worldwide. Almost half show such morphological and molecular variability as to hamper any further classification, and to justify their inclusion in a waste-basket category termed “not otherwise specified (NOS)”. The latter term is used for neoplasms with aggressive presentation, poor response to therapy and dismal prognosis. In contrast to B cell lymphomas, PTCL have been the subject of only a limited number of studies to elucidate their pathobiology and identify novel pharmacological approaches. Herewith, the authors revise the most recent contributions on the subject based on the experience they have gained in the extensive application of microarray technologies. PTCL/NOS are characterised by erratic expression of T cell associated antigens, including CD4 and CD52, which have recently been proposed as targets for ad hoc immunotherapies. PTCL/NOS also show variable Ki-67 marking, with rates >80% heralding a worse prognosis. Gene expression profiling studies have revealed that PTCL/NOS derive from activated T lymphocytes, more often of the CD4+ type, and bear a signature composed of 155 genes and related products that play a pivotal role in cell signalling transduction, proliferation, apoptosis and matrix remodelling. This observation seems to pave the way for the use of innovative drugs such as tyrosine kinase and histone deacetylase inhibitors whose efficacy has been proven in PTCL primary cell cultures. Gene expression profiling also allows better distinction of PTCL/NOS from angioimmunoblastic T cell lymphoma, the latter being characterised by follicular T helper lymphocyte derivation and CXCL13, PD1 and vascular endothelial growth factor expression.

Absolute dose measurements by means of a small cylindrical ionization chamber for very high dose per pulse high energy electron beams

Very high dose per pulse (3-13 cGy/pulse) high energy electron beams are currently produced by special linear accelerators (linac) dedicated to Intra Operative Radiation Therapy (IORT). The electron beams produced by such linacs are collimated by special Perspex applicators of various size and cylindrically shaped. The biggest problems from the dosimetric point of view are caused by the high dose-per-pulse values and the use of inclined applicators. In this work measurements of absolute dose for the inclined applicators were done by using a small cylindrical ionization chamber, type CC01 (Wellhofer), a parallel plane ionization chamber type Markus (PTW 23343) and radiochromic films type EBT. We show a method which allows calculating the quality correction factors for CC01 chamber with an uncertainty of 1% and the absolute dose value for the inclined applicators using CC01 with an uncertainty of 3.1% for electron beams of energy of 6 and 7 MeV produced by the linac dedicated to IORT Novac7.

Recognition of category-related visual stimuli in Parkinson's disease: Before and after pharmacological treatment

Visual-sensory dysfunctions and semantic processing impairments are widely reported in Parkinson's disease (PD) research. The present study investigated the category-specific deficit in object recognition as a function of both the semantic category and spatial frequency content of stimuli. In the first experiment, the role of dopamine in object-recognition processing was assessed by comparing PD drug naïve (PD-DN), PD receiving levodopa treatment (PD-LD), and control subjects. Experiment 2 consisted of a retest session for PD drug naïve subjects after a period of pharmacological treatment. All participants completed an identification task which displayed animals and tools at nine levels of filtering. Each object was revealed in a sequence of frames whereby the object was presented at increasingly less-filtered images up to a complete version of the image. Results indicate an impaired identification pattern for PD-DN subjects solely for animal category stimuli. This differential pharmacological therapy effect was also confirmed at retest (experiment 2). Thus, our data suggest that dopaminergic loss has a specific role in category-specific impairment. Two possible hypotheses are discussed that may account for the defective recognition of semantically different objects in PD.

Serratia marcescens prosthesis infection successfully treated with meropenem after imipenem failure

A 78-year-old woman developed an early knee-prosthesis infection due to multiresistant Serratia marcescens that was successfully treated with high-dose meropenem, after failure of a long-term therapy combining imipenem and multiple surgical interventions. Because of its lower neurotoxicity, meropenem might be preferred to imipenem/cilastatin for the treatment of osteo-articular infections due to multiresistant Gram-negative bacilli in the elderly.

Fast 3D-EM reconstruction using Planograms for stationary planar positron emission mammography camera

At the University of Pisa we are building a PEM prototype, the YAP-PEM camera, consisting of two opposite 6 x 6 x 3 cm3 detector heads of 30 x 30 YAP:Ce finger crystals, 2 x 2 x 30 mm3 each. The camera will be equipped with breast compressors. The acquisition will be stationary. Compared with a whole body PET scanner, a planar Positron Emission Mammography (PEM) camera allows a better, easier and more flexible positioning around the breast in the vicinity of the tumor: this increases the sensitivity and solid angle coverage, and reduces cost. To avoid software rejection of data during the reconstruction, resulting in a reduced sensitivity, we adopted a 3D-EM reconstruction which uses all of the collected Lines Of Response (LORs). This skips the PSF distortion given by data rebinning procedures and/or Fourier methods. The traditional 3D-EM reconstruction requires several times the computation of the LOR-voxel correlation matrix, or probability matrix {p(ij)}; therefore is highly time-consuming. We use the sparse and symmetry properties of the matrix {p(ij)} to perform fast 3D-EM reconstruction. Geometrically, a 3D grid of cubic voxels (FOV) is crossed by several divergent 3D line sets (LORs). The symmetries occur when tracing different LORs produces the same p(ij) value. Parallel LORs of different sets cross the FOV in the same way, and the repetition of p(ij) values depends on the ratio between the tube and voxel sizes. By optimizing this ratio, the occurrence of symmetries is increased. We identify a nucleus of symmetry of LORs: for each set of symmetrical LORs we choose just one LOR to be put in the nucleus, while the others lie outside. All of the possible p(ij) values are obtainable by tracking only the LORs of this nucleus. The coordinates of the voxels of all of the other LORs are given by means of simple translation rules. Before making the reconstruction, we trace the LORs of the nucleus to find the intersecting voxels, whose p(ij) values are computed and stored with their voxel coordinates on a hard disk. Only the non-zero p(ij) are considered and their computation is performed just once. During the reconstruction, the stored values are loaded and are available in the random access memory for all of the operations of normalization, backprojection and projection: these are now performed rapidly, because the application of the translation rules is much faster than the probability computations. We tested the algorithm on Monte Carlo data fully simulating the typical YAP-PEM clinical condition. The adopted algorithm gives an excellent positioning capability for hot spots in the camera FOV. To use all of the possible skew LORs in the FOV avoids the software rejection of collected data. Reconstructed images indicate that a 5mm diameter tumor of 37 kBq/cm3, in an active breast with a 10:1 Tissue to Background ratio (T/B), with a 10 min acquisition, for a head distance of 5 cm, can be detected by the YAP-PEM with a SNR of 8.7+/-1.0. The obtained SNR values depend linearly on the tumor volume. The algorithm allows one to discriminate between two hot sources of 5.0 mm diameter if they do not lie on the same axis. The YAP-PEM is now in the assembly stage.

Identification of a mitochondrial inhibitor of rat liver L-threonine dehydrogenase

In a previous paper, we showed inhibition of rat liver L-threonine dehydrogenase by a preparation obtained by dialysis and concentration from rat liver mitochondria stored at -20 degrees C for 7-10 days (Pagani, R., Leoncini, R., Guerranti, R. and Marinello, E. (1990) It. J. Biochem. 39, 106-114). The chemical composition of the fraction containing the unknown 'inhibitor' has now been studied and identified as D-3-hydroxybutyrate (D3HB).

In situ hybridization at the ultrastructural level: localization of cytomegalovirus DNA using digoxigenin labelled probes

We describe a procedure for detecting and localizing cytomegalovirus DNA sequences based on in situ hybridization at the ultrastructural level. A digoxigenin-labelled probe, identified with an anti-digoxigenin colloidal gold-labelled antiserum, was employed on infected cells embedded in a new acrylic resin (Bioacryl). The silver enhancement method on the same specimen was used to more easily reveal the reaction also at low magnification. The immunolocalization was characterized by high specificity with virtually no background staining and a good maintenance of submicroscopic cell features.