Rotational Molding of Polyamide-6 Nanocomposites with Improved Flame Retardancy

The aim of this work was to develop polyamide-6/ organic-modified montmorillonite (omMMT) nanocomposites for the production of hollow parts by rotational molding. Particular emphasis was placed on the mechanical and flame retardancy properties needed for the fabrication of vessels for flammable liquids. The morphology of the melt compounded nanocomposites, produced by melt compounding, was investigated by X-ray diffraction measurements (WAXD), and Transmission Electron Microscopy (TEM) showed an exfoliated structure. Rheological measurements were used in order to verify whether the viscosity of materials was adequate for rotational molding. While thermomechanical analysis has revealed that neat PA6 and its nanocomposites were not suitable for rotational molding, due to the very low thermal stability of the polymer, the addition of a thermal stabilizer, shifted the onset of degradation to higher temperatures, thus widening the processing window of both PA6 and PA6 nanocomposites. Large-scale vessel prototypes were obtained by rotational molding of thermo-stabilized PA6 and its nanocomposites, and samples extracted from the rotomolded parts were characterized with respect to physical and mechanical properties. It was found that the PA6 nanocomposites exhibited significant improvements at cone calorimeter tests in comparison with neat PA6.

Vogt-Koyanagi-Harada syndrome

OBJECTIVES

The objectives of this study are to review our current knowledge of the aetiopathogenesis of Vogt-Koyanagi-Harada syndrome, including viral infection, genetic factors and immunomediated mechanisms, and to discuss pathogenesis and its relevance to pharmacotherapy.

SYSTEMATIC REVIEW METHODOLOGY

Relevant publications from 1965 to 2012 on the aetiopathogenesis and pharmacotherapy of VKHS were analysed.

RESULTS AND CONCLUSION

Vogt-Koyanagi-Harada syndrome (VKHS) is a rare multisystemic autoimmune disease that affects tissues containing melanin, including the eye, inner ear, meninges, and skin. The disease is characterised by bilateral uveitis associated with a varying constellation of auditory, neurological and cutaneous manifestations. The disease occurs more frequently among people with darker skin pigmentation. Asians, Native Americans, and Hispanics are most frequently affected. It predominates in patients aged between 20 and 50years, and females are affected more frequently, with a female:male ratio of 2:1. The classic clinical course is characterised by bilateral panuveitis, hypoacusis, and meningitis, in addition to cutaneous involvement with poliosis, vitiligo, and alopecia. Although the exact cause of VKH disease remains unknown, it is thought to be a T-cell-mediated autoimmune process directed against melanocytes. VKHS classically begins with vague systemic symptoms suggestive of a viral infection, although a clear association between a specific viral agent and the disease has not been established. Genetic factors may play an important role in the loss of self-tolerance in VKHS. The HLA-DRB1*0405 allele is the main susceptibility allele for VKHS. Early and aggressive systemic corticosteroids are still the primary initial therapy for VKHS. Ocular complications may require an intravitreous injection of corticosteroids. Despite proper treatment with steroids, a number of patients experience recurrent attacks or steroid-associated complications. Thus, non steroid immunomodulatory therapy (IMT) has become necessary for the treatment of VKHS.

Microarray demonstrates different gene expression profiling signatures between Waldenström macroglobulinemia and IgM monoclonal gammopathy of undetermined significance

Waldenström macroglobulinemia (WM) (symptomatic and indolent) and immunoglobulin M (IgM) monoclonal gammopathy of undetermined significance (IgMMGUS) can be identified based on the bone marrow (BM) infiltration and the existence of symptoms. The purpose of this study was to investigate the biological and genetic characteristics of both disorders comparing the molecular signature of WM versus IgMMGUS using microarray analysis. We investigated BM CD19(+) cells isolated from 21 WM patients and 10 IgMMGUS cases, and CD138(+) BM cells isolated from all of the WM patients and 4 of the IgMMGUS cases. Gene expression profiling of WM versus IgMMGUS CD19(+) cells highlighted 151 differently expressed genes and the comparison with CD138(+) cells demonstrated 43 differently expressed genes in WM versus IgMMGUS. Regulation of transcription, Janus kinase/signal transducer and activator of transcription, PI3K/Akt/mammalian target of rapamycin, mitogen-activated protein kinase signaling pathways are the relevant gene ontology biological processes occurring in CD19(+) cells, and immune response, cell activation, and signaling processes developing in CD138(+) cells mainly distinguish WM and IgMMGUS.

A Psychometric Evaluation of the Group Environment Questionnaire in a Sample of Professional Basketball and Soccer Players

Psychometric properties of the Group Environment Questionnaire were investigated in a large sample of soccer ( n = 222) and professional basketball players ( n = 375). Confirmatory factor analysis was performed both on the total sample and on the two subsamples through a multi-group approach; associations between cohesion and the duration of belonging to the team were also explored. Results confirmed the four-factor structure proposed by Carron's original model even though some items with low loadings were eliminated. No significant associations were found between team cohesion and the duration of belonging to the team.

Inhomogeneous kinetic effects related to intermittent magnetic discontinuities

A connection between kinetic processes and two-dimensional intermittent plasma turbulence is observed using direct numerical simulations of a hybrid Vlasov-Maxwell model, in which the Vlasov equation is solved for protons, while the electrons are described as a massless fluid. During the development of turbulence, the proton distribution functions depart from the typical configuration of local thermodynamic equilibrium, displaying statistically significant non-Maxwellian features. In particular, temperature anisotropy and distortions are concentrated near coherent structures, generated as the result of the turbulent cascade, such as current sheets, which are nonuniformly distributed in space. Here, the partial variance of increments (PVI) method has been employed to identify high magnetic stress regions within a two-dimensional turbulent pattern. A quantitative association between non-Maxwellian features and coherent structures is established.

Gene expression profiling identifies ARSD as a new marker of disease progression and the sphingolipid metabolism as a potential novel metabolism in chronic lymphocytic leukemia

BACKGROUND

Several studies demonstrated IGVH mutational status and ZAP70 expression as the most relevant prognostic markers in Chronic Lymphocytic Leukemia (CLL), suggesting the separation of two patient subgroups: with good mutated ZAP70 negative (MTZAP70(-) and poor unmutated ZAP70 positive (UMZAP70(+)) prognosis.

DESIGN AND METHODS

We determined the gene expression of B cells in 112 CLL patients divided into three classes: class 1 with MTZAP70(-), class 2 with UMZAP70(+), and class 3 included both UMZAP70(-) and MTZAP70(+).

RESULTS

We found LPL, AGPAT2, MBOAT1, CHPT1, AGPAT4, PLD1 genes encoding enzymes involved in lipid metabolism overexpressed in UMZAP70(+). In addition, this study identified ARSD, a gene belonging to the sphingolipid metabolism, as a new gene significantly overexpressed in UMZAP70(+) compared to MTZAP70(-). Western blots confirmed that ARSD protein levels were significantly different between the 3 classes of patients and normal controls. Statistical analysis identified a significant correlation between ARSD and IGVH; however, both ARSD protein level and IGVH were independently associated with the need for therapy of CLL patients.

CONCLUSIONS

ARSD is a novel prognostic factor as the time to start therapy is shorter in patients with high levels of ARSD protein and sphingolipid metabolism could represent a new biological mechanism in CLL.

Magnetic moment nonconservation in magnetohydrodynamic turbulence models

The fundamental assumptions of the adiabatic theory do not apply in the presence of sharp field gradients or in the presence of well-developed magnetohydrodynamic turbulence. For this reason, in such conditions the magnetic moment μ is no longer expected to be constant. This can influence particle acceleration and have considerable implications in many astrophysical problems. Starting with the resonant interaction between ions and a single parallel propagating electromagnetic wave, we derive expressions for the magnetic moment trapping width Δμ (defined as the half peak-to-peak difference in the particle magnetic moments) and the bounce frequency ω(b). We perform test-particle simulations to investigate magnetic moment behavior when resonance overlapping occurs and during the interaction of a ring-beam particle distribution with a broadband slab spectrum. We find that the changes of magnetic moment and changes of pitch angle are related when the level of magnetic fluctuations is low, δB/B(0) = (10(-3),10(-2)), where B(0) is the constant and uniform background magnetic field. Stochasticity arises for intermediate fluctuation values and its effect on pitch angle is the isotropization of the distribution function f(α). This is a transient regime during which magnetic moment distribution f(μ) exhibits a characteristic one-sided long tail and starts to be influenced by the onset of spatial parallel diffusion, i.e., the variance <(Δz)(2)> grows linearly in time as in normal diffusion. With strong fluctuations f(α) becomes completely isotropic, spatial diffusion sets in, and the f(μ) behavior is closely related to the sampling of the varying magnetic field associated with that spatial diffusion.

Meniere's disease might be an autoimmune condition?

OBJECTIVES

To review our current knowledge of the pathogenesis of Meniere's disease, including viral infection and immune system-mediated mechanisms, and to discuss the pathogenesis as it relates to pharmacotherapy.

SYSTEMATIC REVIEW METHODOLOGY

Relevant publications on the aetiopathogenesis, molecular biology, genetics and histopathology of Meniere's disease from 1861 to 2011 were analysed.

RESULTS AND CONCLUSIONS

Meniere's disease is characterised by intermittent episodes of vertigo, fluctuating sensorineural hearing loss, tinnitus, and aural pressure. The aetiology and pathogenesis remain unknown. Proposed theories of causation include viral infections and immune system-mediated mechanisms. The immune response in Meniere's disease is focused on inner ear antigens. Approximately one-third of Meniere's disease cases seem to be of an autoimmune origin although the immunological mechanisms involved are not clear. The diagnosis of autoimmune inner ear disease is based either on clinical criteria or on a positive response to steroids. The antiviral approach has virtually eliminated the use of various surgical methods used in the past. Steroid responsiveness is high, and with prompt treatment, inner ear damage may be reversible. The administration of etanercept improves or stabilises symptoms in treated patients. Treatment of antiphospholipid syndrome can be directed toward preventing thromboembolic events by using antithrombotic medications. Only warfarin has been shown to be effective. Gene therapy can be used to transfer genetic material into inner ear cells using viral vectors and to protect, rescue, and even regenerate hair cells of the inner ear.

Concomitant evaluation of flow-mediated vasodilation and epicardial fat thickness in idiopathic deep venous thrombosis

Flow mediated vasodilation (FMD) evaluates the endothelium-dependent vasodilation, is a reliable marker of arterial endothelial dysfunction and is related to coronary artery disease. Visceral fat predicts an unfavorable cardiovascular and metabolic risk profile in humans and echocardiographic assessment of epicardial fat (EF) is a reliable marker of visceral adiposity. We measured the FMD and EF thickness in 77 subjects, 38 without idiopathic deep vein thrombosis (DVT) (mean age 65.95 ± 16.29 years) and 39 with idiopathic DVT (mean age 65.49 ± 17.22 years). The purpose of this work is to investigate the presence of statistical association between FMD and DVT and between EF thickness and DVT. Furthermore, to account for possible atherosclerosis risk factor unbalances, comparison between FMD and DVT (and between EF and DVT) was assessed using a multivariate logistic regression model which included the following covariates: FMD, EF, age, sex, smoking and the presence of obesity. Subjects without DVT showed significant lower values of EF thickness (9.07 ± 1.89 mm vs 12.32 ± 1.73 mm, p=0.005) and borderline-significant greater values of FMD (9.01 ± 2.77 percent vs 7.47 ± 5.37 percent, p=0.058) as compared to those with DVT. In conclusion, the data presented indicate that subjects affected by spontaneous deep vein thrombosis may have an impaired endothelium-dependent vasodilation, a marker of arterial endothelial dysfunction related to coronary artery disease, and an increased epicardial adipose tissue, a marker of cardiometabolic risk.

On the deconvolution analysis of electrodermal activity in bipolar patients

People affected by bipolar disorders experience alternating states of depression with episodes of mania or hypomania. This mental can lead to a poor handling of daily routines, can worsen personal relationships, and often can be life-threatening. This preliminary study aims at investigating how the autonomic nervous system, in terms of electrodermal activity, responds to specific controlled emotional stimuli in bipolar patients. More specifically, we present here a method to deploy the analysis of ElectroDermal Activity (EDA) to discriminate clinical mood states. EDA was analyzed by using a deconvolution method to separate tonic from phasic components. The three subjects recruited and the experimental protocol used here is part of the European project PSYCHE. Preliminary results show that the bipolar mood states can be related to electrodermal tonic activity.

Time-Related Dynamics of Variation in Core Clock Gene Expression Levels in Tissues Relevant to the Immune System

Immune parameters show rhythmic changes with a 24-h periodicity driven by an internal circadian timing system that relies on clock genes (CGs). CGs form interlocked transcription-translation feedback loops to generate and maintain 24-h mRNA and protein oscillations. In this study we evaluate and compare the profiles and the dynamics of variation of CG expression in peripheral blood, and two lymphoid tissues of mice. Expression levels of seven recognized key CGs (mBmall, mClock, mPer1, mPer2, mCry1, mCry2, and Rev-erbα) were evaluated by quantitative RT- PCR in spleen, thymus and peripheral blood of C57BL/6 male mice housed on a 12-h light (L)-dark (D) cycle and sacrificed every 4 h for 24 h (3–4 mice/time point). We found a statistically significant time-effect in spleen (S), thymus (T) and blood (B) for the original values of expression level of mBmal1 (S), mClock (T, B), mPer1 (S, B), mPer2 (S), mCry1 (S), mCry2 (B) and mRev-Erbα (S, T, B) and for the fractional variation calculated between single time-point expression value of mBmal1 (B), mPer2 (T), mCry2 (B) and mRev-Erbα (S). A significant 24-h rhythm was validated for five CGs in blood (mClock, mPer1, mPer2, mCry2, mRev-Erbα), for four CGs in the spleen (mBmal1, mPer1, mPer2, mRev-Erbα), and for three CGs in the thymus (mClock, mPer2, mRev-Erbα). The original values of acrophases for mBmal1, mClock, mPer1, mPer2, mCry1 and mCry2 were very similar for spleen and thymus and advanced by several hours for peripheral blood compared to the lymphoid tissues, whereas the phases of mRev-Erbα were coincident for all three tissues. In conclusion, central and peripheral lymphoid tissues in the mouse show different sequences of activation of clock gene expression compared to peripheral blood. These differences may underlie the compartmental pattern of web functioning in the immune system.

Factors predicting transformation of asymptomatic IgM monoclonal gammopathy

We evaluated the risk of transformation of asymptomatic immunoglobulin (Ig) M monoclonal gammopathy (aIgM MG) into symptomatic lymphoproliferative disease in 287 patients all analyzed for bone marrow histopathology and immunophenotyping. This series included 201 patients with IgM MG of undetermined significance (IgM MGUS) and 86 with smoldering Waldenström's macroglobulinemia (sWM). After a median of 50 months (range, 12-322 months), 32 cases of aIgM-MG (11.1%) evolved into symptomatic malignant lymphoproliferative disease, as follows: symptomatic WM (n=26), non-Hodgkin lymphoma (n=6). The cumulative transformation percentage at 5 and 10 years was 8% and 19.5%, respectively. The parameters significantly correlated with evolution were, at univariate analysis, BM lymphoplasmacytic infiltration, high erythrocyte sedimentation rate, serum MC, serum IgM size, and serum IgA size. Among patients with aIgM-MG, those at high risk of evolution were patients with sWM, a distinct entity with serum IgM monoclonal protein≥3 g/dL and/or ≥10% bone marrow lymphoplasmacytic infiltration.

Alteration of circadian rhythmicity of CD3+CD4+ lymphocyte subpopulation in healthy aging

The CD4+ T helper/inducer and the CD8+ T suppressor/cytotoxic are major lymphocyte subsets that play a key role in cell-mediated immunity. Aging-related changes of immune function have been demonstrated. The purpose of this study is to analyze the dynamics of variation of these specific lymphocyte subsets in the elderly. In our study cortisol and melatonin serum levels were measured and lymphocyte subpopulation analyses were performed on blood samples collected every four hours for 24 hours from fifteen healthy young middle-aged subjects (age range 36-55 years) and fifteen healthy elderly male subjects (age range 67-79 years). A clear circadian rhythm was validated for the time-qualified changes of CD3+ and CD4+ cells with acrophase at night and for the time-qualified changes of CD8+ cells with acrophase at noon in young middle-aged subjects and for the time-qualified changes of CD3+ cells with acrophase at night and for the time-qualified changes of CD8+ cells with acrophase at noon in elderly subjects. No clear circadian rhythm was validated for the time-qualified changes of CD4+ cells in elderly subjects. No statistically significant correlation among lymphocyte subsets was found in elderly subjects. In elderly subjects CD3+ lymphocyte percentage was higher in the photoperiod and in the scotoperiod and cortisol serum level were higher in the scotoperiod in respect to young middle-aged subjects. In the elderly there is an alteration of circadian rhythmicity of T helper/inducer lymphocytes and this phenomenon might contribute to the aging-related changes of immune responses.

Increased levels of the Akt-specific phosphatase PH domain leucine-rich repeat protein phosphatase (PHLPP)-1 in obese participants are associated with insulin resistance

AIMS/HYPOTHESIS

We determined the contribution to insulin resistance of the PH domain leucine-rich repeat protein phosphatase (PHLPP), which dephosphorylates Akt at Ser473, inhibiting its activity. We measured the abundance of PHLPP in fat and skeletal muscle from obese participants. To study the effect of PHLPP on insulin signalling, PHLPP (also known as PHLPP1) was overexpressed in HepG2 and L6 cells.

METHODS

Subcutaneous fat samples were obtained from 82 morbidly obese and ten non-obese participants. Skeletal muscle samples were obtained from 12 obese and eight non-obese participants. Quantification of PHLPP-1 in human tissues was performed by immunoblotting. The functional consequences of recombinant PHLPP1 overexpression in hepatoma HepG2 cells and L6 myoblasts were investigated.

RESULTS

Of the 82 obese participants, 31 had normal fasting glucose, 33 impaired fasting glucose and 18 type 2 diabetes. PHLPP-1 abundance was twofold higher in the three obese groups than in non-obese participants (p = 0.004). No differences were observed between obese participants with normal fasting glucose, impaired fasting glucose or type 2 diabetes. PHLPP-1 abundance was correlated with basal Akt Ser473 phosphorylation (r = -0.48; p = 0.001), BMI (r = 0.44; p < 0.0001), insulin (r = 0.35; p < 0.0001) and HOMA (r = 0.38; p < 0.0001). PHLPP-1 abundance was twofold higher in the skeletal muscle of 12 obese participants than in that of eight non-obese participants (p < 0.0001). Insulin treatment of HepG2 cells resulted in a dose- and time-dependent upregulation of PHLPP-1. Overexpression of PHLPP1 in HepG2 cells and L6 myoblasts resulted in impaired insulin signalling involving Akt/glycogen synthase kinase 3, glycogen synthesis and glucose transport.

CONCLUSIONS/INTERPRETATION

Increased abundance of PHLPP-1, production of which is regulated by insulin, may represent a new molecular defect in insulin-resistant states such as obesity.