Diffusion kurtosis imaging probes cortical alterations and white matter pathology following cuprizone induced demyelination and spontaneous remyelination.

Although MRI is the gold standard for the diagnosis and monitoring of multiple sclerosis (MS), current conventional MRI techniques often fail to detect cortical alterations and provide little information about gliosis, axonal damage and myelin status of lesioned areas. Diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) provide sensitive and complementary measures of the neural tissue microstructure. Additionally, specific white matter tract integrity (WMTI) metrics modelling the diffusion in white matter were recently derived. In the current study we used the well-characterized cuprizone mouse model of central nervous system demyelination to assess the temporal evolution of diffusion tensor (DT), diffusion kurtosis tensor (DK) and WMTI-derived metrics following acute inflammatory demyelination and spontaneous remyelination. While DT-derived metrics were unable to detect cuprizone induced cortical alterations, the mean kurtosis (MK) and radial kurtosis (RK) were found decreased under cuprizone administration, as compared to age-matched controls, in both the motor and somatosensory cortices. The MK remained decreased in the motor cortices at the end of the recovery period, reflecting long lasting impairment of myelination. In white matter, DT, DK and WMTI-derived metrics enabled the detection of cuprizone induced changes differentially according to the stage and the severity of the lesion. More specifically, the MK, the RK and the axonal water fraction (AWF) were the most sensitive for the detection of cuprizone induced changes in the genu of the corpus callosum, a region less affected by cuprizone administration. Additionally, microgliosis was associated with an increase of MK and RK during the acute inflammatory demyelination phase. In regions undergoing severe demyelination, namely the body and splenium of the corpus callosum, DT-derived metrics, notably the mean diffusion (MD) and radial diffusion (RD), were among the best discriminators between cuprizone and control groups, hence highlighting their ability to detect both acute and long lasting changes. Interestingly, WMTI-derived metrics showed the aptitude to distinguish between the different stages of the disease. Both the intra-axonal diffusivity (Da) and the AWF were found to be decreased in the cuprizone treated group, Da specifically decreased during the acute inflammatory demyelinating phase whereas the AWF decrease was associated to the spontaneous remyelination and the recovery period. Altogether our results demonstrate that DKI is sensitive to alterations of cortical areas and provides, along with WMTI metrics, information that is complementary to DT-derived metrics for the characterization of demyelination in both white and grey matter and subsequent inflammatory processes associated with a demyelinating event.

Dioxin-like Compounds in Lake Fish Species: Evaluation by DR-CALUX Bioassay.

Fish consumption is the principal source of intake of organochlorinated compounds in humans. Compared with other types of foods of animal origin, fish contain the highest levels of polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p-dioxins, and polychlorinated dibenzofurans, all of which are classified as highly toxic organochlorine compounds. Currently, lakes and fish farms in northern Italy are not regularly monitored for PCBs and dioxins in areas contaminated by industrial sources, partially because of the high costs of traditional analytical methods that limit the number of samples to be analyzed. The DR-CALUX cell bioassay is based on the uptake of the cellular aryl hydrocarbon receptor (AhR) for dioxins and dioxin-like compounds. The aim of this study was to assess the levels of dioxins and dioxin-like PCB contamination in Lake Maggiore and Lake Como, two lakes in northwestern Italy, and in nearby areas. The levels were quantified using the cell bioassay DR-CALUX and reference controls in two wild fish species, perch ( Perca fluviatilis) and roach ( Rutilus rutilus), and in a farmed species, rainbow trout ( Oncorhynchus mykiss). Tissue samples collected from the farmed rainbow trout were also submitted to immunohistochemical analysis of CYP1A expression as a marker for environmental pollutant-induced liver damage. The levels of dioxins, furans, and dioxin-like PCBs were all below the maximum levels and action limits set by European Union Regulation, suggesting no risk for human health associated with the consumption of the fish species caught or farmed in these areas.

[Bacteremia in tonsillectomy: Sluder's technique versus dissection. Preliminary results]. / Batteriemia in corso di tonsillectomia: tecnica di Sluder versus dissezione. Risultati preliminari.

Fifty-one patients undergoing elective tonsillectomy for recurrent acute tonsillitis, 21 by dissection tonsillectomy (41%), and 30 guillotine tonsillectomy (59%). Positive post-operative blood cultures were obtained in 22 patients (43%), but only 4 in the dissection group (19%) and in 18 of the guillotine group (60%). Streptococci (21.5%) and Staphylococci (9.8%) are the commonest organisms cultured. This data are suggestive for the necessity of an antibiotic prophylaxis before tonsillectomy.

Identification by a proteomic approach of a plasma protein as a possible biomarker of illicit dexamethasone treatment in veal calves.

Corticosteroids have become the most widespread illegal growth promoters in veal calves and beef cattle. Testing for corticosteroids relies on either direct detection of compounds or their metabolites or indirect detection to identify changes in biological pathways. We used a comparative proteomic approach, based on two-dimensional electrophoresis (2DE), to identify plasma protein markers after short-term dexamethasone administration in veal calves. Twenty-three male Friesian veal calves were treated experimentally with dexamethasone sodium phosphate: 10 received low-dose administration of the drug (0.4 mg day⁻¹ per os) for 20 consecutive days (treatment group); 10 received the drug at therapeutic dosage (2-4 mg kg⁻¹ i.m.) for 3 consecutive days (comparison group). Three animals were not treated (control group). Plasma samples were collected from each animal at six time points (T1-T6; treatment and control group) and at four time points (T1-T4; comparison group) and stored at -80°C until analysis. Plasma proteins were quantified and analysed in triplicate by 2DE. The images were analysed with Bionumerics® software. Comparison of 2DE maps obtained from blood samples at T1 (before treatment) and at T6 (final sampling) showed a significant disappearance (p < 0.001) of two protein spots at T6 in the treatment group. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis and immunoblotting identified these isoforms as serum paraoxonase/arylesterase 1 precursor (PON1). Synthesised in the liver and released into the blood, PON1 has an important role in lipid metabolism. The absence of variation of this protein in the comparison group suggests that the marker has good specificity for detecting illicit corticosteroid treatment.

Acute complicated sphenoiditis in childhood. Case report and literature review.

In ENT practice, acute uncomplicated sphenoiditis is rarely diagnosed: very often diagnosis is involved for multiform and unspecific symptomatology, such as to sham nervous, visual and upper respiratory tract diseases. Only a careful differential diagnostics and an instrumental investigation consents to realise quickly a specific treatment, avoiding some complications, still frequent. This case-report, underlines that the polyspecialists' co-operation is necessary to make a correct diagnosis, and to avert important and dangerous complications into shapes of sphenoiditis.

[Air pollution in the daily environment: study of a school-children population]. / L'inquinamento atmosferico nei luoghi di vita quotidiana. Studio di una popolazione di bambini in etá scolare.

BACKGROUND: To evaluate the annual distribution of personal exposure to NO2 in a sample of school children and to study the determinants of such exposure. METHODS: Exposure to NO2 has been evaluated using Palmes Tubes in 310 school-children (aged 5-14) in Novara. The possible differences in personal measurements by means of ANOVA and Tuckey test were evaluated. Information on the sources of potential exposure and on respiratory symptoms have been collected through a questionnaire and a clinical diary. The relative risk for these variables has been assessed using a multiple regression model (Logit). RESULTS: The annual mean of the 6,200 measurements was 42.3 microgram/m3, with a significant difference among seasons and with higher values in winter. The only factor associated with a high exposure was identified for maternal school children living in houses close to high traffic density roads. Respiratory symptoms were non-related to NO2. CONCLUSIONS: The use of gas cookers and heaters is not enough to explain the variability of personal exposure. Between other specific determinants, the importance of living along busy streets, of ETS and of seasons explains the level of personal exposure. The opportunity of personal, rather than environmental, monitoring is confirmed, even if we stress the necessity of studying the short-term exposure to rapidly find clinical damages in the general population.