Testing for spatial autocorrelation: the regressors that make the power disappear

We show that for any sample size, any size of the test, and any weights matrix outside a small class of exceptions, there exists a positive measure set of regression spaces such that the power of the Cli-Ord test vanishes as the autocorrelation increases in a spatial error model. This result extends to the tests that dene the Gaussian power envelope of all invariant tests for residual spatial autocorrelation. In most cases, the regression spaces such that the problem occurs depend on the size of the test, but there also exist regression spaces such that the power vanishes regardless of the size. A characterization of such particularly hostile regression spaces is provided

AB0051 SERUM AMYLOID A AND PENTRAXIN 3: INNATE IMMUNE RESPONSE AND DISEASE ACTIVITY IN SYSTEMIC LUPUS ERYTHEMATOSUS

Background:Systemic Lupus Erythematosus (SLE) is an autoimmune disease that involves several molecular patterns with a wide spectrum of clinical manifestations and symptoms. Inflammation and related pathway play a role in SLE pathogenesis. The pentraxin superfamily including long and short pentraxin, C Reactive Protein CRP, Serum amyloid A (SAA), Pentraxin 3 (PTX3) are key components of innate immune system and induce a variety of inflammation associated pathway. However Literature provides several evidences that CRP serum levels not correlated with clinical and immunological manifestations. This situation affected clinical practice and the patient follow up. PTX3 have been identified as a component of inflammatory status in several autoimmune conditions. SAA is an acute phase protein secreted in large quantity during inflammation.Objectives:We want to evaluated SAA, PTX3 and CRP concentrations, their correlation between SLE Disease Activity Index (SLEDAI), that including complement fractions C3, C4.Methods:We enrolled fifty patients that fulfilled the SLE American College of Rheumatology criteria and fifty healthy subjects. The SLE disease activity was classified with the SLEDAI (0 to 12). Patients were divided into two groups according to SLEDAI score: inactive group (Group 1, 25 patients, 50%: SLEDAI < 4) and active group (Group 2, 25 patients, 50%: SLEDAI 5 to 12). PTX3 concentration was measured by a sandwich ELISA kit (Hycult) with 2.8 ng/mL cut-off point. SAA concentration was detected by nephelometry performed on a BN ProSpec System (Siemens, Germany), with assay kit based on polyclonal antibodies (Siemens Healthcare Diagnostics Products, Germany, 6.5 mg/L cut-off point). High sensitive CRP concentrations were determined using the ci8200 platform (Abbott Laboratories Chicago, Illinois).Results:Plasma PTX3 and serum SAA levels was significantly higher in SLE patients than in the healthy subjects (PTX311.5 ± 7.3 ng/mL vs 2.3 ± 1.1; p < 0.001; SAA: 87 ±77 mg/L vs 2.6±2.5; p < 0.001). These differences were not evident in CRP levels (8.5 ± 7.8 mg/L vs 6.2± 2.5). Considering two groups, there were statistical differences in PTX3 level (Group 2: 14.9 ± 12 ng/mL vs Group 1: 2.16 ±0.5 ng/mL, p<0,05) and SAA concentration (Group 2: 114 ± 89 ng/mL vs Group 1: 3.6 ±1.7 ng/mL, p<0,05) but not in CRP concentration (Group 2: 11.5 ± 8.4 mg/L vs Group 1: 9.5 ±3.5). There was a significantly negative correlation between C3, C4 fractions, PTX3 and SSA levels (respectively r = −0.74, p=<0.05, and r = −0.79, p<0.05). No statistical correlation were appeared between C3, C4 fractions and CRP serum levels (r= −0,12., p= 0.82, and r= −0.18, p= 0,21). We noted a positive significant correlation between SLEDAI, PTX3 and SAA concentration (r = 0.79, p < 0.05, 0.83, p < 0.05, respectively) an increase in PTX3 and SAA levels followed the lupus flare and symptoms. No significant correlation appeared between SLEDAI and CRP (r= 0.15, p=0.89)Conclusion:PTX3 and SAA concentration was significantly higher in SLE patients than the healthy control subjects and their levels reflected disease activity. We showed a direct correlation between PTX3 and SAA. In SLE patients PTX3 and SAA concentrations were correlated with SLEDAI. We suggest an integrate viewpoint in witch SAA and PTX3 may play a role as a biomarker of disease activity, with synergic work during SLE events. Evidences suggested that PTX3 and SAA could trigger the same molecular pathway, by TLR4, via NF-kB.References:[1]Assandri R, Monari M Montanelli A. Pentraxin 3 in Systemic Lupus Erithematosus: Questions to be Resolved, Translational Biomedicine (2015)Disclosure of Interests:None declare

0.5-50 GHz dielectric characterisation of breast cancer tissues

Cancer affects a significant percentage of people, and early detection techniques are important for prompt and effective treatment. The use of microwave frequencies to achieve non-invasive and non-destructive cancer detections is currently under investigation by several research groups. In this frequency range, the dielectric properties of the biological tissue determine the interactions of the tissue with electromagnetic fields. Knowledge of the dielectric properties of both the normal and the malignant human tissues is therefore a fundamental starting point. A dielectric spectroscopy system, based on the use of a reflectometry setup, was used to perform an extensive experimental campaign on fresh surgical specimens. The measurement system allowed achieving a broadband dielectric characterisation of biological tissues up to 50 GHz, thus including millmetre-wave (mm-wave) frequencies. In the case of breast tissues, the results showed that the malignant and normal tissues exhibit significantly different complex dielectric permittivities of up to 50 GHz, due to their respective high and low water content. This permittivity difference is well detectable, and this paves the way to new screening methods based on mm-wave imaging systems

Cerebellar neurons and glial cells are transducible by lentiviral vectors without decrease of cerebellar functions

Due to the profuse connections of the cerebellum to the rest of the central nervous system, cerebellar dysfunction impacts tremendously on movement coordination, maintenance of equilibrium, muscle tone and motor memory. Efficient gene transfer of therapeutic genes to this central nervous system structure would constitute a relevant step ahead the design of treatments to ameliorate cerebellar dysfunction. Lentiviral vectors (LVs) have been used as efficient vehicles to integrate transgenes into dividing and non-dividing cells, such as postmitotic adult neurons, with minimal toxicity and immune response. This study aimed to use LVs carrying green fluorescent protein (GFP) cDNA for transduction of cerebellar cells in vivo without compromising neurological cerebellar functions. Our results indicate that LVs, injected in the lobulus simplex, transduced different cerebellar neurons including stellate, Purkinje cells, granular neurons and glial cells such as astrocytes, oligodendrocytes, and that this gene transfer approach was not accompanied by cerebellar deficits