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Background: Niemann-Pick disease type C (NP-C) is a rare, autosomal recessive neurodegenerative disease caused by mutations in either the NPC1 or NPC2 genes. The diagnosis of NP-C remains challenging due to the non-specific, heterogeneous nature of signs/symptoms. This study assessed the utility of plasma chitotriosidase (ChT) and Chemokine (C-C motif) ligand 18 (CCL18)/pulmonary and activation-regulated chemokine (PARC) in conjunction with the NP-C suspicion index (NP-C SI) for guiding confirmatory laboratory testing in patients with suspected NP-C. Methods: In a prospective observational cohort study, incorporating a retrospective determination of NP-C SI scores, two different diagnostic approaches were applied in two separate groups of unrelated patients from 51 Spanish medical centers (n = 118 in both groups). From Jan 2010 to Apr 2012 (Period 1), patients with =2 clinical signs/symptoms of NP-C were considered ''suspected NP-C'' cases, and NPC1/NPC2 sequencing, plasma chitotriosidase (ChT), CCL18/PARC and sphingomyelinase levels were assessed. Based on findings in Period 1, plasma ChT and CCL18/PARC, and NP-C SI prediction scores were determined in a second group of patients between May 2012 and Apr 2014 (Period 2), and NPC1 and NPC2 were sequenced only in those with elevated ChT and/or elevated CCL18/PARC and/or NP-C SI =70. Filipin staining and 7-ketocholesterol (7-KC) measurements were performed in all patients with NP-C gene mutations, where possible. Results: In total across Periods 1 and 2, 10/236 (4%) patients had a confirmed diagnosis o NP-C based on gene sequencing (5/118 4.2%] in each Period): all of these patients had two causal NPC1 mutations. Single mutant NPC1 alleles were detected in 8/236 (3%) patients, overall. Positive filipin staining results comprised three classical and five variant biochemical phenotypes. No NPC2 mutations were detected. All patients with NPC1 mutations had high ChT activity, high CCL18/PARC concentrations and/or NP-C SI scores =70. Plasma 7-KC was higher than control cut-off values in all patients with two NPC1 mutations, and in the majority of patients with single mutations. Family studies identified three further NP-C patients. Conclusion: This approach may be very useful for laboratories that do not have mass spectrometry facilities and therefore, they cannot use other NP-C biomarkers for diagnosis.

It is shown that, apart from the neutron interaction contribution to the susceptibility of neutron stars, there is an additional contribution coming from the magnetic polarizability beta /sub n/ of individual neutrons. For beta /sub n/ approximately=10/sup -4/fm/sup 3 /, this part overwhelms the interaction contribution for k/sub F/>or approximately=3.5fm/sup -1/. No transition to ferromagnetic state is predicted in the interesting density region. (8 refs).

Se analiza el comportamiento de una ecuación de iteraciones del tipo armónico con parámetros dentro del argumento. Se observa que este mapa tiene varios atractores y competencia entre los mismos. Se calculan los coeficientes de Liapunov para cada zona de atracción Fil: Izaguirre, E.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales (UBA-FCEyN). Departamento de Física. Buenos Aires. Argentina Fil: Ferro Fontan, C.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales (UBA-FCEyN). Departamento de Física. Buenos Aires. Argentina Fil: Mancini, H.. Centro de Investigaciones en Láseres y Aplicaciones (CONICET –CITEFA). Buenos Aires. Argentina

Se analiza e implementa un sistema híbrido electroóptico realimentado en el cual la señal es discretizada. De esta manera su dinámica queda descripta en forma exacta por una ecuación de recurrencias armónica, con los parámetros de control dentro del argumento, (amplificación del lazo de realimentación y rotación de fase) Fil: Izaguirre, E.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales (UBA-FCEyN). Departamento de Física. Buenos Aires. Argentina Fil: Ferro Fontan, C.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales (UBA-FCEyN). Departamento de Física. Buenos Aires. Argentina Fil: Mancini, H.. Centro de Investigaciones en Láseres y Aplicaciones (CONICET –CITEFA). Buenos Aires. Argentina

A model for the annihilation of electron-positron pairs into hadrons for q/sup 2/=s>4 GeV/sup 2/ and up to the highest measured energies is developed. The main ingredients are point-like couplings between three resonances and photons and the high level of opening thresholds that follows from an effective Lagrangian formalism. The model gives an almost constant annihilation cross section, soft pions everywhere and at all energies, high multiplicities and a large absolute cross section. The details of all exclusive channels are also predicted. Other consequences of this point of view concern the discovery of hitherto ignored couplings in three resonances and photons and the high level of opening threshold that follows from an effective Lagrangian formalism. The model gives an almost constant annihilation cross section, soft pions everywhere and at all energies, high multiplicities and a large absolute crosssection. The details of all exclusive channels are also predicted. Other consequences of this point of view concern the discovery of hitherto ignored couplings in low-energy photon initiated reactions. It is argued that the energy regime explored by SPEAR is not the asymptopia and possible further constancy of the cross section in a range of s is discussed. (4 refs).