Some Probabilistic Results in a Bisexual Branching Process with Immigration

2000 Mathematics Subject Classification: 60J80.A bisexual branching process with immigration of females and males is introduced. It is allowed, in each generation, that the mating function and the probability distributions associated to the offspring and the immigration may change depending on the number of progenitor couples. Relationships among the probability generating functions involved in the model and some transition and stochastic monotony properties are established.This research has been supported by the Ministerio de Ciencia y Tecnologia and the FEDER through the Plan Nacional de Investigacion Cientifica, Desarrollo e Innovaci on Tecnologica, grant BFM2003-06074

Estimation of the Offspring and Immigration Mean Vectors for Bisexual Branching Processes with Immigration of Females and Males

2000 Mathematics Subject Classification: 60J80, 62M05.This paper concerns with the bisexual branching model with immigration of females and males in each generation introduced in [4]. For this model the problem of estimating the offspring and immigration mean vectors is dealt. The estimation is considered in two sample situations, depending on the ability to observe the number of female and male immigrants or the impossibility to do it. The asymptotic properties of the proposed estimators are investigated in the supercritical case. The behaviour of the estimators is illustrated through a simulated example.Research supported by the Ministerio de Ciencia e Innovacion and the FEDER through the Plan Nacional de Investigacion Cientıfica, Desarrollo e Innovacion Tecnologica, grant MTM2009-13248

Versatile Graphene-Based Platform for Robust Nanobiohybrid Interfaces

Technologically useful and robust graphene-based interfaces for devices require the introduction of highly selective, stable, and covalently bonded functionalities on the graphene surface, whilst essentially retaining the electronic properties of the pristine layer. This work demonstrates that highly controlled, ultrahigh vacuum covalent chemical functionalization of graphene sheets with a thiol-terminated molecule provides a robust and tunable platform for the development of hybrid nanostructures in different environments. We employ this facile strategy to covalently couple two representative systems of broad interest: metal nanoparticles, via S-metal bonds, and thiol-modified DNA aptamers, via disulfide bridges. Both systems, which have been characterized by a multi-technique approach, remain firmly anchored to the graphene surface even after several washing cycles. Atomic force microscopy images demonstrate that the conjugated aptamer retains the functionality required to recognize a target protein. This methodology opens a new route to the integration of high-quality graphene layers into diverse technological platforms, including plasmonics, optoelectronics, or biosensing. With respect to the latter, the viability of a thiol-functionalized chemical vapor deposition graphene-based solution-gated field-effect transistor array was assessed

Kidins220 deficiency causes ventriculomegaly via SNX27-retromer-dependent AQP4 degradation

Several psychiatric, neurologic and neurodegenerative disorders present increased brain ventricles volume, being hydrocephalus the disease with the major manifestation of ventriculomegaly caused by the accumulation of high amounts of cerebrospinal fluid (CSF). The molecules and pathomechanisms underlying cerebral ventricular enlargement are widely unknown. Kinase D interacting substrate of 220 kDa (KIDINS220) gene has been recently associated with schizophrenia and with a novel syndrome characterized by spastic paraplegia, intellectual disability, nystagmus and obesity (SINO syndrome), diseases frequently occurring with ventriculomegaly. Here we show that Kidins220, a transmembrane protein effector of various key neuronal signalling pathways, is a critical regulator of CSF homeostasis. We observe that both KIDINS220 and the water channel aquaporin-4 (AQP4) are markedly downregulated at the ventricular ependymal lining of idiopathic normal pressure hydrocephalus (iNPH) patients. We also find that Kidins220 deficient mice develop ventriculomegaly accompanied by water dyshomeostasis and loss of AQP4 in the brain ventricular ependymal layer and astrocytes. Kidins220 is a known cargo of the SNX27-retromer, a complex that redirects endocytosed plasma membrane proteins (cargos) back to the cell surface, thus avoiding their targeting to lysosomes for degradation. Mechanistically, we show that AQP4 is a novel cargo of the SNX27-retromer and that Kidins220 deficiency promotes a striking and unexpected downregulation of the SNX27-retromer that results in AQP4 lysosomal degradation. Accordingly, SNX27 silencing decreases AQP4 levels in wild-type astrocytes whereas SNX27 overexpression restores AQP4 content in Kidins220 deficient astrocytes. Together our data suggest that the KIDINS220-SNX27-retromer-AQP4 pathway is involved in human ventriculomegaly and open novel therapeutic perspectives

Andrea Chénier

Programa de les funcions d'"Andrea Chénier" d'U. Giordano amb llibret de L. Illica, que van tenir lloc al Gran Teatre del Liceu durant el mes de novembre de 1985. El repartiment va estar format per L. Bartolini com Andrea Chénier, V. Sarindero com a Carlo Gérard, E. Marton com a Maddalena, R. M. Ysàs com la mulata Bersi, C. Fondevila com la comtessa de Coigny, M. Aparici com a Madelon, A. Echeverría com a Roucher, V. Esteve com a Pietro Fleville i Fouquier Tinville, G. Tosi com el "sanculotto" Mathieu, Piero de Palma com un "incredibile", A. Heilbron com l'Abate i J. Castillón com a Schmidt, el majordom i DumasOrquestra del Gran Teatre del Liceu dirigida per Romano Gandolf

Combination of KIR2DS4 and FcγRIIa polymorphisms predicts the response to cetuximab in KRAS mutant metastatic colorectal cancer

Cetuximab is a standard-of-care treatment for RAS wild-type metastatic colorectal cancer (mCRC) but not for those harbor a KRAS mutation since MAPK pathway is constitutively activated. Nevertheless, cetuximab also exerts its effect by its immunomodulatory activity despite the presence of RAS mutation. The aim of this study was to determine the impact of polymorphism FcγRIIIa V158F and killer immunoglobulin-like receptor (KIR) genes on the outcome of mCRC patients with KRAS mutations treated with cetuximab. This multicenter Phase II clinical trial included 70 mCRC patients with KRAS mutated. We found KIR2DS4 gene was significantly associated with OS (HR 2.27; 95% CI, 1.08–4.77; P = 0.03). In non-functional receptor homozygotes the median OS was 2.6 months longer than in carriers of one copy of full receptor. Multivariate analysis confirmed KIR2DS4 as a favorable prognostic marker for OS (HR 6.71) in mCRC patients with KRAS mutation treated with cetuximab. These data support the potential therapeutic of cetuximab in KRAS mutated mCRC carrying non-functional receptor KIR2DS4 since these patients significantly prolong their OS even after heavily treatment. KIR2DS4 typing could be used as predictive marker for identifying RAS mutated patients that could benefit from combination approaches of anti-EGFR monoclonal antibodies and other immunotherapies to overcome the resistance mediated by mutation in RAS.This clinical trial was approved and supported by Merck S.L., an affiliate of Merck KGaA, Darmstadt. Germany [research project number 2010-023580-18, date: 05-06-2014

Excitotoxic inactivation of constitutive oxidative stress detoxification pathway in neurons can be rescued by PKD1

Excitotoxicity, a critical process in neurodegeneration, induces oxidative stress and neuronal death through mechanisms largely unknown. Since oxidative stress activates protein kinase D1 (PKD1) in tumor cells, we investigated the effect of excitotoxicity on neuronal PKD1 activity. Unexpectedly, we find that excitotoxicity provokes an early inactivation of PKD1 through a dephosphorylation-dependent mechanism mediated by protein phosphatase-1 (PP1) and dual specificity phosphatase-1 (DUSP1). This step turns off the IKK/NF-κB/SOD2 antioxidant pathway. Neuronal PKD1 inactivation by pharmacological inhibition or lentiviral silencing in vitro, or by genetic inactivation in neurons in vivo, strongly enhances excitotoxic neuronal death. In contrast, expression of an active dephosphorylation-resistant PKD1 mutant potentiates the IKK/NF-κB/SOD2 oxidative stress detoxification pathway and confers neuroprotection from in vitro and in vivo excitotoxicity. Our results indicate that PKD1 inactivation underlies excitotoxicity-induced neuronal death and suggest that PKD1 inactivation may be critical for the accumulation of oxidation-induced neuronal damage during aging and in neurodegenerative disorders