A network landscape model: stability analysis and numerical tests

Versão dos autores para este artigo.A Network Landscape Model (NLM) for the evaluation of the ecological trend of an environmental system is here presented and investigated. The model consists in a network of dynamical systems, here each node represents a single Landscape Unit (LU), endowed by a system of ODEs for two variables relevant to the production of bio-energy and to the percentage of green areas, respectively. The main goal of the paper consists in testing the relevance of connectivity between the LUs. For this purpose we consider rst the Single LU Model (SLM) and investigate its equilibria and their stability, in terms of two bifurcation parameters. Then the network dynamics is theoretically investigated by means of a bifurcation analysis of a proper simpli ed di erential system, that allows to understand how the coupling between di erent LUs modi es the asymptotic scenarios for the single LU model. Numerical simulations of NLM are performed, with reference to an environmental system in Northern Italy, and results are discussed in connection with SLM.GNFM - INdAM; FC

Inherited human gp91phox deficiency is associated with impaired isoprostane formation and platelet dysfunction

Platelet isoprostane 8-ISO-prostaglandin F2α (8-iso-PGF2α), a proaggregating molecule, is believed to derive from nonenzymatic oxidation of arachidonic acid. We hypothesized that NADPH is implicated in isoprostane formation and platelet activation

Hereditary Deficiency of gp91(phox) Is Associated With Enhanced Arterial Dilatation Results of a Multicenter Study

Background-NADPH oxidase is believed to modulate arterial tone, but its role in humans is still unclear. The objective of this study was to evaluate whether NADPH oxidase is involved in flow-mediated arterial dilation (FMD). Methods and Results-Twenty-five patients with hereditary deficiency of gp91(phox), the catalytic core of NADPH oxidase, (X-CGD), 25 healthy subjects, and 25 obese patients matched for sex and age were recruited. FMD, platelet gp91(phox), serum levels of nitrite and nitrate as markers of nitric oxide generation, oxidized low-density lipoprotein, and urinary excretion of isoprostanes as markers of oxidative stress were determined. Platelet gp91(phox) expression was downregulated in X-CGD patients (1.0+/-0.8 mean fluorescence; P<0.001) and upregulated in obese patients (4.1+/-2.2 mean fluorescence; P=0.01) compared with healthy subjects (2.9+/-1.7 mean fluorescence). Urinary excretion of isoprostanes was reduced in X-CGD patients (41.7+/-33.3 pg/mg creatinine; P = 0.04) and increased in obese patients (154.4+/-91 pg/mg creatinine; P<0.001) compared with healthy subjects (69.5+/-52.4 pg/mg creatinine). Obese patients had higher serum oxidized low-density lipoprotein than healthy subjects (35.3+/-6.7 versus 24.8+/-9.8 U/L; P<0.001) and X-CGD patients (28.5+/-7.2 U/L; P<0.001). X-CGD patients had significantly higher FMD (14.7+/-5.9%) compared with healthy subjects (7.9+/-2.5%; P<0.001); obese patients had lower FMD (5.3+/-3.0%; P+/-0.028) compared with healthy subjects. Serum nitrite and nitrate levels were significantly higher in patients with X-CGD (36.0+/-10.8+/-mol/L; P<0.016) and lower in obese patients (9.3+/-11.0 mu mol/L; P<0.001) compared with healthy subjects (27.1+/-19.1 mu mol/L). Serum nitrite and nitrate levels significantly correlated with FMD (R-s = 0.403, P<0.001) and platelet gp91(phox) (R-s = -0.515, P<0.001). FMD inversely correlated with platelet gp91(phox) (R-s = -0.502, P<0.001) and isoprostanes (R-s = -0.513, P<0.001). Conclusion-This study provides the first evidence that, in humans, gp91(phox) is implicated in the modulation of arterial ton

Intergenerational and intrafamilial phenotypic variability in 22q11.2 deletion syndrome subjects

BACKGROUND: 22q11.2 deletion syndrome (22q11.2DS) is a common microdeletion syndrome, which occurs in approximately 1:4000 births. Familial autosomal dominant recurrence of the syndrome is detected in about 8-28% of the cases. Aim of this study is to evaluate the intergenerational and intrafamilial phenotypic variability in a cohort of familial cases carrying a 22q11.2 deletion. METHODS: Thirty-two 22q11.2DS subjects among 26 families were enrolled. RESULTS: Second generation subjects showed a significantly higher number of features than their transmitting parents (212 vs 129, P = 0.0015). Congenital heart defect, calcium-phosphorus metabolism abnormalities, developmental and speech delay were more represented in the second generation (P < 0.05). Ocular disorders were more frequent in the parent group. No significant difference was observed for the other clinical variables. Intrafamilial phenotypic heterogeneity was identified in the pedigrees. In 23/32 families, a higher number of features were found in individuals from the second generation and a more severe phenotype was observed in almost all of them, indicating the worsening of the phenotype over generations. Both genetic and epigenetic mechanisms may be involved in the phenotypic variability. CONCLUSIONS: Second generation subjects showed a more complex phenotype in comparison to those from the first generation. Both ascertainment bias related to patient selection or to the low rate of reproductive fitness of adults with a more severe phenotype, and several not well defined molecular mechanism, could explain intergenerational and intrafamilial phenotypic variability in this syndrome

Activated phosphoinositide 3-dinase delta syndrome (APDS): An update

Activated phosphoinositide 3-kinase delta syndrome (APDS) is a recently described form of inborn error of immunity (IEI) caused by heterozygous mutations in PIK3CD or PIK3R1&nbsp;genes, respectively, encoding leukocyte-restricted catalytic p110\u3b4 subunit and the ubiquitously expressed regulatory p85 \u3b1 subunit of the phosphoinositide 3-kinase \u3b4 (PI3K\u3b4). The first described patients with respiratory infections, hypogammaglobulinemia with normal to elevated IgM serum levels, lymphopenia, and lymphoproliferation. Since the original description, it is becoming evident that the onset of disease may be somewhat variable over time, both in terms of age at presentation and in terms of clinical and immunological complications. In many cases, patients are referred to various specialists such as hematologists, rheumatologists, gastroenterologists, and others, before an immunological evaluation is performed, leading to delay in diagnosis, which negatively affects their prognosis. The significant heterogeneity in the clinical and immunological features affecting APDS patients requires awareness among clinicians since good results with p110\u3b4 inhibitors have been reported, certainly ameliorating these patients\u2019 quality of life and prognosis

Impaired natural killer cell functions in patients with signal transducer and activator of transcription 1 (STAT1) gain-of-function mutations

Gain-of-function (GOF) mutations affecting the coiled-coil domain or the DNA-binding domain of signal transducer and activator of transcription 1 (STAT1) cause chronic mucocutaneous candidiasis disease. This condition is characterized by fungal and bacterial infections caused by impaired generation of TH17 cells; meanwhile, some patients with chronic mucocutaneous candidiasis disease might also have viral or intracellular pathogen infections

Inherited defects in the complement system

open13noThe complement system plays an essential role in both innate and adaptive immune responses. Any dysregulation in this system can disturb normal host defense and alter inflammatory response leading to both infections and autoimmune diseases. The complement system can be activated through three different pathways. Inherited complement deficiencies have been described for all complement components and their regulators. Despite being rare diseases, complement deficiencies are often severe, with a frequent onset during childhood. We provide an overview of clinical disorders related to these disorders and describe current diagnostic strategies required for their comprehensive characterization and management.openLeonardi L.; La Torre F.; Soresina A.; Federici S.; Cancrini C.; Castagnoli R.; Cinicola B.L.; Corrente S.; Giardino G.; Lougaris V.; Volpi S.; Marseglia G.L.; Cardinale F.Leonardi, L.; La Torre, F.; Soresina, A.; Federici, S.; Cancrini, C.; Castagnoli, R.; Cinicola, B. L.; Corrente, S.; Giardino, G.; Lougaris, V.; Volpi, S.; Marseglia, G. L.; Cardinale, F

Primary atopic disorders and chronic skin disease

open13noPrimary atopic disorders (PADs) are monogenic diseases characterized by allergy or atopy-related symptoms as fundamental features. In patients with PADs, primary immune deficiency and immune dysregulation symptoms are usually coexist. Chronic skin disease, manifesting with erythroderma, severe atopic dermatitis or eczema, and urticaria, is one of the main features observed in PADs, such as hyper-IgE syndromes, Omenn syndrome, Wiskott-Aldrich syndrome, IPEX-linked syndrome, skin barrier disorders, as well as some autoinflammatory diseases. The recognition of PADs in the context of an allergic phenotype is crucial to ensure prompt diagnosis and appropriate treatment. This article provides an overview of the main PADs with skin involvement.openCinicola B.L.; Corrente S.; Castagnoli R.; Lougaris V.; Giardino G.; Leonardi L.; Volpi S.; La Torre F.; Federici S.; Soresina A.; Cancrini C.; Marseglia G.L.; Cardinale F.Cinicola, B. L.; Corrente, S.; Castagnoli, R.; Lougaris, V.; Giardino, G.; Leonardi, L.; Volpi, S.; La Torre, F.; Federici, S.; Soresina, A.; Cancrini, C.; Marseglia, G. L.; Cardinale, F