siRNA-Mediated Knock-Down of P-Glycoprotein Expression Reveals Distinct Cellular Disposition of Anticancer Tyrosine Kinases Inhibitors.

Studies on the cellular disposition of targeted anticancer tyrosine kinases inhibitors (TKIs) have mostly focused on imatinib while the functional importance of P-glycoprotein (Pgp) the gene product of MDR1 remains controversial for more recent TKIs. By using RNA interference-mediated knockdown of MDR1, we have investigated and compared the specific functional consequence of Pgp on the cellular disposition of the major clinically in use TKIs imatinib, dasatinib, nilotinib, sunitinib and sorafenib. siRNA-mediated knockdown in K562/Dox cell lines provides a unique opportunity to dissect the specific contribution of Pgp to TKIs intracellular disposition. In these conditions, abrogating specifically Pgp-mediated efflux in vitro revealed the remarkable and statistically significant cellular accumulation of imatinib (difference in cellular levels between Pgp-expressing and silenced cells, at high and low incubation concentration, respectively: 6.1 and 6.6), dasatinib (4.9 and 5.6), sunitinib (3.7 and 7.3) and sorafenib (1.2 and 1.4), confirming that these TKIs are all substrates of Pgp. By contrast, no statistically significant difference in cellular disposition of nilotinib was observed as a result of MDR1 expression silencing (differences: 1.1 and 1.5) indicating that differential expression and/or function of Pgp is unlikely to affect nilotinib cellular disposition. This study enables for the first time a direct estimation of the specific contribution of one transporter among the various efflux and influx carriers involved in the cellular trafficking of these major TKIs in vitro. Knowledge on the distinct functional consequence of Pgp expression for these various TKIs cellular distribution is necessary to better appreciate the efficacy, toxicity, and potential drug-drug interactions of TKIs with other classes of therapeutic agents, at the systemic, tissular and cellular levels.

Liquid fructose down-regulates liver insulin receptor substrate 2 and gluconeogeneic enzymes by modifying nutrient sensing factors in rats

High consumption of fructose-sweetened beverages has been linked to a high prevalence of chronic metabolic diseases. We have previously shown that a short course of fructose supplementation as a liquid solution induces glucose intolerance in female rats. In the present work, we characterized the fructose-driven changes in the liver and the molecular pathways involved. To this end, female rats were supplemented or not with liquid fructose (10%, w/v) for 7 or 14 days. Glucose and pyruvate tolerance tests were performed, and the expression of genes related to insulin signaling, gluconeogenesis and nutrient sensing pathways was evaluated. Fructose-supplemented rats showed increased plasma glucose excursions in glucose and pyruvate tolerance tests and reduced hepatic expression of several genes related to insulin signaling, including insulin receptor substrate 2 (IRS-2). However, the expression of key gluconeogenic enzymes, glucose-6-phosphatase and phosphoenolpyruvate carboxykinase, was reduced. These effects were caused by an inactivation of hepatic forkhead box O1 (FoxO1) due to an increase in its acetylation state driven by a reduced expression and activity of sirtuin 1 (SIRT1). Further contributing to FoxO1 inactivation, fructose consumption elevated liver expression of the spliced form of X-box-binding-protein-1 as a consequence of an increase in the activity of the mammalian target of rapamycin 1 and protein 38-mitogen activated protein kinase (p38-MAPK). Liquid fructose affects both insulin signaling (IRS-2 and FoxO1) and nutrient sensing pathways (p38-MAPK, mTOR and SIRT1), thus disrupting hepatic insulin signaling without increasing the expression of key gluconeogenic enzymes.

Natural gene-expression variation in Down syndrome modulates the outcome of gene-dosage imbalance.

Down syndrome (DS) is characterized by extensive phenotypic variability, with most traits occurring in only a fraction of affected individuals. Substantial gene-expression variation is present among unaffected individuals, and this variation has a strong genetic component. Since DS is caused by genomic-dosage imbalance, we hypothesize that gene-expression variation of human chromosome 21 (HSA21) genes in individuals with DS has an impact on the phenotypic variability among affected individuals. We studied gene-expression variation in 14 lymphoblastoid and 17 fibroblast cell lines from individuals with DS and an equal number of controls. Gene expression was assayed using quantitative real-time polymerase chain reaction on 100 and 106 HSA21 genes and 23 and 26 non-HSA21 genes in lymphoblastoid and fibroblast cell lines, respectively. Surprisingly, only 39% and 62% of HSA21 genes in lymphoblastoid and fibroblast cells, respectively, showed a statistically significant difference between DS and normal samples, although the average up-regulation of HSA21 genes was close to the expected 1.5-fold in both cell types. Gene-expression variation in DS and normal samples was evaluated using the Kolmogorov-Smirnov test. According to the degree of overlap in expression levels, we classified all genes into 3 groups: (A) nonoverlapping, (B) partially overlapping, and (C) extensively overlapping expression distributions between normal and DS samples. We hypothesize that, in each cell type, group A genes are the most dosage sensitive and are most likely involved in the constant DS traits, group B genes might be involved in variable DS traits, and group C genes are not dosage sensitive and are least likely to participate in DS pathological phenotypes. This study provides the first extensive data set on HSA21 gene-expression variation in DS and underscores its role in modulating the outcome of gene-dosage imbalance.

Down-regulation of interferon signature in systemic lupus erythematosus patients by active immunization with interferon α-kinoid.

OBJECTIVE: We developed interferon-α-kinoid (IFN-K), a drug composed of inactivated IFNα coupled to a carrier protein, keyhole limpet hemocyanin. In human IFNα-transgenic mice, IFN-K induces polyclonal antibodies that neutralize all 13 subtypes of human IFNα. We also previously demonstrated that IFN-K slows disease progression in a mouse model of systemic lupus erythematosus (SLE). This study was undertaken to examine the safety, immunogenicity, and biologic effects of active immunization with IFN-K in patients with SLE. METHODS: We performed a randomized, double-blind, placebo-controlled, phase I/II dose-escalation study comparing 3 or 4 doses of 30 μg, 60 μg, 120 μg, or 240 μg of IFN-K or placebo in 28 women with mild to moderate SLE. RESULTS: IFN-K was well tolerated. Two SLE flares were reported as serious adverse events, one in the placebo group and the other in a patient who concomitantly stopped corticosteroids 2 days after the first IFN-K dose, due to mild fever not related to infection. Transcriptome analysis was used to separate patients at baseline into IFN signature-positive and -negative groups, based on the spontaneous expression of IFN-induced genes. IFN-K induced anti-IFNα antibodies in all immunized patients. Notably, significantly higher anti-IFNα titers were found in signature-positive patients than in signature-negative patients. In IFN signature-positive patients, IFN-K significantly reduced the expression of IFN-induced genes. The decrease in IFN score correlated with the anti-IFNα antibody titer. Serum complement C3 levels were significantly increased in patients with high anti-IFNα antibody titers. CONCLUSION: These results show that IFN-K is well tolerated, immunogenic, and significantly improves disease biomarkers in SLE patients, indicating that further studies of its clinical efficacy are warranted.

The complex SNP and CNV genetic architecture of the increased risk of congenital heart defects in Down syndrome.

Congenital heart defect (CHD) occurs in 40% of Down syndrome (DS) cases. While carrying three copies of chromosome 21 increases the risk for CHD, trisomy 21 itself is not sufficient to cause CHD. Thus, additional genetic variation and/or environmental factors could contribute to the CHD risk. Here we report genomic variations that in concert with trisomy 21, determine the risk for CHD in DS. This case-control GWAS includes 187 DS with CHD (AVSD = 69, ASD = 53, VSD = 65) as cases, and 151 DS without CHD as controls. Chromosome 21-specific association studies revealed rs2832616 and rs1943950 as CHD risk alleles (adjusted genotypic P-values <0.05). These signals were confirmed in a replication cohort of 92 DS-CHD cases and 80 DS-without CHD (nominal P-value 0.0022). Furthermore, CNV analyses using a customized chromosome 21 aCGH of 135K probes in 55 DS-AVSD and 53 DS-without CHD revealed three CNV regions associated with AVSD risk (FDR ≤ 0.05). Two of these regions that are located within the previously identified CHD region on chromosome 21 were further confirmed in a replication study of 49 DS-AVSD and 45 DS- without CHD (FDR ≤ 0.05). One of these CNVs maps near the RIPK4 gene, and the second includes the ZBTB21 (previously ZNF295) gene, highlighting the potential role of these genes in the pathogenesis of CHD in DS. We propose that the genetic architecture of the CHD risk of DS is complex and includes trisomy 21, and SNP and CNV variations in chromosome 21. In addition, a yet-unidentified genetic variation in the rest of the genome may contribute to this complex genetic architecture.

Sindrome metabolica e rischio di tumore mammario. [Metabolic syndrome and the risk of breast cancer].

Metabolic syndrome has been associated with an increased risk of various cancers. A multicenter study conducted in Italy and Switzerland on 3,869 cases of breast cancer in post-menopause reported a relative risk of 1.75 in women with the metabolic syndrome, confirming the results of other smaller epidemiological studies.

Indicadores cognitivos del proceso de envejecimiento en las personas con síndrome de Down

Fundamentos: el aumento de la esperanza de vida en las personas con síndrome de Down plantea nuevos interrogantes sobre el proceso de su envejecimiento. La revisión bibliográfica sobre el tema muestra acuerdo sobre algunos aspectos diferenciales respecto a la población con discapacidad psíquica y la población general. Entre ellos, destacamos dos: a) la precocidad del inicio del proceso y b) el aumento de la probabilidad de desarrollar un envejecimiento patológico a causa de la demencia tipo Alzheimer. El objetivo del presente estudio se centra en la aportación de datos que ayuden a delimitar los posibles indicadores del declive cognitivo de las personas adultas con síndrome de Down relacionados con un posible deterioro propio de la demencia tipo Alzheimer. Método: el estudio se realiza en una muestra de 84 personas adultas con discapacidad psíquica, 42 de las cuales presentan el síndrome de Down. La media de edad se sitúa entorno a los 40 años y su nivel de retraso mental es medio. Se aplica de forma longitudinal en un período de dos años el test d’Aptituds Cognitives per a Deficiència del 65% (Castelló, Carrillo y Barnosell, 1996). Se utiliza un diseño factorial mixto de medidas repetidas controlando las variables etiología, edad cronológica, nivel de retraso mental y paso del tiempo. Resultados: se observa con el paso del tiempo, un declive cognitivo significativo de las personas con síndrome de Down de más de 38 años y nivel de retraso mental ligero respecto al grupo con discapacidad psíquica de referencia. Los indicadores cognitivos se sitúan preferentemente en las áreas de lenguaje y coordinación visomotora. Conclusiones: las personas con síndrome de Down de más de 38 años y nivel de retraso mental ligero manifiestan una probabilidad mayor de desarrollar un declive cognitivo relacionado con un probable deterioro propio de la demencia Alzheimer.

Dyrk1A is dynamically expressed on subsets of motor neurons and in the neuromuscular junction: possible role in Down syndrome

Individuals with Down syndrome (DS) present important motor deficits that derive from altered motor development of infants and young children. DYRK1A, a candidate gene for DS abnormalities has been implicated in motor function due to its expression in motor nuclei in the adult brain, and its overexpression in DS mouse models leads to hyperactivity and altered motor learning. However, its precise role in the adult motor system, or its possible involvement in postnatal locomotor development has not yet been clarified. During the postnatal period we observed time-specific expression of Dyrk1A in discrete subsets of brainstem nuclei and spinal cord motor neurons. Interestingly, we describe for the first time the presence of Dyrk1A in the presynaptic terminal of the neuromuscular junctions and its axonal transport from the facial nucleus, suggesting a function for Dyrk1A in these structures. Relevant to DS, Dyrk1A overexpression in transgenic mice (TgDyrk1A) produces motor developmental alterations possibly contributing to DS motor phenotypes and modifies the numbers of motor cholinergic neurons, suggesting that the kinase may have a role in the development of the brainstem and spinal cord motor system.

Procurement and inventory management in product ramp down

Tuotteiden elinkaaret elektroniikkateollisuudessa ovat lyhentyneet entisestään. Paineet uusien kehittyneempien tuotteiden lanseeraamiselle ovat kasvaneet. Huonosti hoidettu tuotevaihto voi aiheuttaa merkittäviä kustannuksia yritykselle mikäli alasajon kustannusvaikutusta tulokseen aliarvioidaan. Työ käsittelee markkinoilta poistuvan tuotteen materiaalivirtojen hallintaa tuotevaihdon aikana. Lähtökohtana työssä oli kehittää toimintatapa miten tuotteen alasajon aikana tulisi toimia sekä mallintaa hankintaketju riskien ja pullonkaulojen löytämiseksi. Päätavoitteena oli materiaalivaraston arvon minimoiminen sekä ylijäämämateriaalien hyödyntäminen. Työn merkittävimpiä tuloksia oli hankintaketjun materiaalivirtojen seurantaan kehitetty Excel työkalu sekä alasajon liittyvien työvaiheiden kuvaaminen.

DOPPLERVELOCIMETRIA DO DUTO VENOSO NO CÁLCULO DE RISCO PARA SÍNDROME DE DOWN NO PRIMEIRO TRIMESTRE DA GRAVIDEZ

OBJETIVO: Investigar a validade da Dopplervelocimetria do duto venoso em detectar a síndrome de Down entre 10 e 14 semanas de gestação e propor novo cálculo de risco. PACIENTES E MÉTODOS: Foram estudados 491 fetos, consecutivamente. Em 132 casos realizou-se estudo citogenético no material obtido por biópsia de vilosidade coriônica e em 359 o resultado baseou-se no fenótipo do recém-nascido. Em todos os fetos realizaram-se, além da ultra-sonografia de rotina, a medida da translucência nucal e a Dopplervelocimetria do duto venoso. Na análise estatística foram utilizados o teste paramétrico T de "student", a análise de variância e a regressão linear. Posteriormente, calcularam-se: sensibilidade, especificidade, valores preditivos positivo e negativo, probabilidade de falso-positivo e razões de probabilidades. RESULTADOS: Ocorreram 21 casos de trissomia do cromossomo 21. Desses casos, o fluxo no duto venoso durante a contração atrial foi ausente em três casos e reverso em 17 - sensibilidade de 95,2%. No grupo de fetos normais (470 casos), oito avaliações mostraram alterações do Doppler do duto venoso (especificidade de 98,2%, valores preditivos positivo e negativo de 71,4% e 99,8%, respectivamente, e razões de probabilidades positiva e negativa de 56 e 0,1, respectivamente). CONCLUSÕES: Nossos resultados preliminares sugerem que a presença de síndrome de Down pode ser fortemente suspeitada se houver fluxo reverso ou ausente no duto venoso. Especulamos a possibilidade de cálculo de novo risco para trissomia do 21 com base no Doppler do duto venoso. Utilizando o programa de risco da Fetal Medicine Foundation como risco basal, teríamos um fator multiplicador de aproximadamente 0,1 (razão de probabilidade negativa), caso duto normal, ou de 50 (razão de probabilidade positiva), caso duto reverso ou ausente, e assim, teremos novo risco corrigido.