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Quantitative positron emission tomography (PET) heart studies require the accurate localization of regions of interest (ROIs) on the myocardial wall (MW) and left ventricle (LV). The procedure is often inaccurate, especially when there is low tracer uptake. We implemented a data processing technique to improve the accuracy of the localization of ROIs on the MW and LV in fluorine-18 labelled deoxyglucose ([F]FDG) PET heart studies. This technique combines transmission data, acquired before tracer administration and used for attenuation correction, and dynamic emission data (DY), acquired to obtain myocardial time-activity curves and used to calculate regional myocardial glucose utilization, to generate a new set of 'transmission' images (TRDY) with enhanced contrast between MW and LV. These new transmission images identify the extravascular myocardial tissue and can be used for ROI placement. Validation of the method was performed in 25 patients, studied after an oral glucose load, by drawing irregular ROIs on three transaxial slices outlining the septum and anteriorapical and lateral wall on the last frame of the DY images (steady state) and then on the TRDY images. Two kinds of analysis were performed on a total of 225 myocardial segments: (1) mean counts per pixel in the DY images from ROIs independently drawn on DY and TRDY images were compared; (2) TRDY ROIs were copied onto DY images and repositioned in the event of mismatch between ROIs and myocardial tissue edge. Mean counts per pixel in the DY images from the original and the repositioned TRDY ROIs were compared. An excellent correlation was found in both cases (using TRDY and DY ROIs: y=0.908 x+0.068, r=0.97; using TRDY ROIs alone: y=0.975 x+0.006, r=0.99). This technique can be used for clinical applications in physiological and pathological conditions in which the myocardial [F]FDG uptake is reduced or minimal, including diabetes and myocardial infarction. [ABSTRACT FROM AUTHOR]

Prejudices on psychiatric disorders frequently turn into stigmatizating attitudes, also among health care providers. The Opening Minds Stigma Scale for Health Care Providers (OMS-HC) was introduced in 2012 to measure stigma. No Italian versions of this tool exist so far. We wanted to investigate stigma among healthcare students in Italy, and to prepare an Italian version of the scale. A multicentric, cross-sectional study was conducted on a sample of Nursing, Physiotherapy, Occupational therapy, and Dietistics students. The Italian version of the scale was obtained through back-translation.
561 students were enrolled, median age 21 years, IQR [20;23], 62.22% females (n = 349). 262 students declared having met subjetcs affected by psychiatric disorders during their training; 50 had one or more psychiatric disorders in their lives. The Italian version proved valid and reliable. Older students had lower stigma scores. No differences existed between stigma scores according to gender and personal experience of mental illness.

In total 1095 samples from 675 pork products, 210 swine colon contents, and 210 swine carcass sponge swabs were collected in Umbria and Marche regions of Italy and examined for the presence of Shiga toxin-producing Escherichia coli (STEC), also known as Verotoxin-producing E. coli (VTEC). After an enrichment step, each sample was analysed by real-time PCR to detect the stx1, stx2, and eae genes. stx-Positive samples were further tested for the "top five" serogroup markers (O157, O26, O103, O111, O145) and cultured onto selective media. The isolates were assigned to stx subtypes and tested for the presence of aaiC and aggR genes. Out of 420 swine samples, 38.6% faecal samples and 13.8% carcass sponge swabs were stx-positive. In total, 33 E. coli STEC isolates were obtained from 30 samples (4 carcasses and 26 colon contents) indicating a culture-positive rate of 7.1%. A higher culture-positive rate was observed in faecal samples (12.4%) than in carcass sponge swabs (1.9%). Out of 675 pork samples, 19 (2.8%) were stx-positive. No STEC strains were isolated from stx-positive pork products. We concluded that STEC isolation from foodstuffs remains difficult, despite the application of ISO/TS 13136:2012. Furthermore, in accordance with the results of studies conducted in other countries, we observed that most of swine STEC strains carried stx2e gene and lacked of virulence genes, such as eae, aaiC and aggR, indicative of potential pathogenic characteristics for humans. Although the majority of STEC isolates did not express virulence factors correlating with severe human diseases, the association between swine STEC strains and human illness requires further investigations., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

This study investigated two foodborne outbreaks of gastroenteritis that occurred 10 days apart among individuals who had meals at the restaurant of a farm holiday resort. Mild gastrointestinal symptoms were reported and none of the patients needed hospitalization. Mean incubation times were 45 and 33 h, and the overall attack rates were 43.5 and 58.3%, respectively. Stool sample examination was negative for common enteric pathogens in both outbreaks. Specimens from 13 people involved in the second outbreak and 3 restaurant staff were examined for diarrhoeagenic Escherichia coli. An enteroaggregative E. coli (EAEC) strain of serotype O92:H33 was isolated from six participants and one member of staff. In particular, the EAEC strain was isolated from five of the six cases of diarrhoea examined. The strain showed an aggregative pattern of adherence to HEp-2 cells, did not produce a biofilm and possessed the virulence-related genes aat, aggR, aap and set1A, but not the astA gene. A retrospective cohort study indicated a pecorino cheese made with unpasteurized sheep milk as the possible source (P<0.001). Samples of the cheese had E. coli counts higher than 10(6) c.f.u. g(-1), but the outbreak EAEC strain was not isolated. This report confirms that EAEC infections are probably underdiagnosed because of the limited availability of laboratories capable of identifying this group of pathogenic E. coli.

A hybrid method for attenuation correction (HAC) in positron emission tomography (PET) brain studies is proposed. The technique requires the acquisition of two short (1 min) transmission scans immediately before or after the emission study, with the patient and the head fixation system in place and after removing the patient from the scanner with the head fixation system alone. The method combines a uniform map of attenuation coefficients for the patient's head with measured attenuation coefficients for the head fixation system to generate a hybrid attenuation map. The HAC method was calibrated on 30 PET cerebral studies for comparison with the conventional measured attenuation correction method by ROI analysis. Average differences of less than 3% were found for cortical and subcortical regions. The HAC technique is particularly suitable in a PET clinical environment, allowing a reduction of the total study time, greater comfort for patients and an increase in patient throughput.

Functional tissue heterogeneity, i.e., inclusion of tissues with different rates of blood flow and metabolism within a single region of interest, is an unavoidable problem with PET. Errors in determination of regional cerebral glucose utilization (rCMRglc) with [18F]FDG have resulted from the currently used simplifying assumption that all regions examined are homogeneous. We have established an optimal, yet practical procedure to minimize errors due to tissue heterogeneity in determination of rCMRglc. Effects of applying the three-rate constant kinetic model designed for homogeneous tissues with both dynamic and single-scan procedures and the Patlak plot were evaluated in normal subjects in experimental periods up to 120 min following tracer injection. The procedure with a single scan carried out any time within the interval between 60 and 120 min following tracer injection, combined with population average rate constants determined over a 120-min period, was found to be optimal for quantitative rCMRglc studies.

A procedure for patient repositioning and compensation for misalignment between transmission and emission data in positron emission tomography (PET) heart studies has been developed. Following the transmission scan (TR1), patients are moved from the scanner bed for the administration of the tracer, and repositioned when ready for the emission scan (EM1). A short postinjection transmission scan (TR2) is performed at the end of the EM1 study. TR1 and TR2 images are compared to recognize misalignment between transmission and emission studies. TR1 sinograms are compensated for misalignment to allow for a proper attenuation correction. The procedure has been tested on phantom and [18F]FDG PET heart studies. Misalignments down to 2.5 mm translation and 1 degree rotation in the transaxial plane and 4 mm in the axial direction can be recognized and compensated for. The procedure is suitable for clinical purposes, allowing reduction of patient time on the scanner bed, increased patient comfort and significant increase of patient throughput.