427 research outputs found

    Argosomes A Potential Vehicle for the Spread of Morphogens through Epithelia

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    AbstractThe formation of morphogen gradients is essential for tissue patterning. Morphogens are released from producing cells and spread through adjacent tissue; paradoxically, however, many morphogens, including Wingless, associate tightly with the cell membrane. Here, we describe a novel cell biological mechanism that disperses membrane fragments over large distances through the Drosophila imaginal disc epithelium. We call these membrane exovesicles argosomes. Argosomes are derived from basolateral membranes and are produced by many different regions of the disc. They travel through adjacent tissue where they are found predominantly in endosomes. Wingless protein colocalizes with argosomes derived from Wingless-producing cells. The properties of argosomes are consistent with their being a vehicle for the spread of Wingless protein

    Compression-based classification of biological sequences and structures via the Universal Similarity Metric: experimental assessment

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    <p>Abstract</p> <p>Background</p> <p>Similarity of sequences is a key mathematical notion for Classification and Phylogenetic studies in Biology. It is currently primarily handled using alignments. However, the alignment methods seem inadequate for post-genomic studies since they do not scale well with data set size and they seem to be confined only to genomic and proteomic sequences. Therefore, alignment-free similarity measures are actively pursued. Among those, USM (Universal Similarity Metric) has gained prominence. It is based on the deep theory of Kolmogorov Complexity and <it>universality </it>is its most novel striking feature. Since it can only be approximated via data compression, USM is a methodology rather than a formula quantifying the similarity of two strings. Three approximations of USM are available, namely UCD (Universal Compression Dissimilarity), NCD (Normalized Compression Dissimilarity) and CD (Compression Dissimilarity). Their applicability and robustness is tested on various data sets yielding a first massive quantitative estimate that the USM methodology and its approximations are of value. Despite the rich theory developed around USM, its experimental assessment has limitations: only a few data compressors have been tested in conjunction with USM and mostly at a qualitative level, no comparison among UCD, NCD and CD is available and no comparison of USM with existing methods, both based on alignments and not, seems to be available.</p> <p>Results</p> <p>We experimentally test the USM methodology by using 25 compressors, all three of its known approximations and six data sets of relevance to Molecular Biology. This offers the first systematic and quantitative experimental assessment of this methodology, that naturally complements the many theoretical and the preliminary experimental results available. Moreover, we compare the USM methodology both with methods based on alignments and not. We may group our experiments into two sets. The first one, performed via ROC (Receiver Operating Curve) analysis, aims at assessing the <it>intrinsic </it>ability of the methodology to discriminate and classify biological sequences and structures. A second set of experiments aims at assessing how well two commonly available classification algorithms, UPGMA (Unweighted Pair Group Method with Arithmetic Mean) and NJ (Neighbor Joining), can use the methodology to perform their task, their performance being evaluated against gold standards and with the use of well known statistical indexes, i.e., the F-measure and the partition distance. Based on the experiments, several conclusions can be drawn and, from them, novel valuable guidelines for the use of USM on biological data. The main ones are reported next.</p> <p>Conclusion</p> <p>UCD and NCD are indistinguishable, i.e., they yield nearly the same values of the statistical indexes we have used, accross experiments and data sets, while CD is almost always worse than both. UPGMA seems to yield better classification results with respect to NJ, i.e., better values of the statistical indexes (10% difference or above), on a substantial fraction of experiments, compressors and USM approximation choices. The compression program PPMd, based on PPM (Prediction by Partial Matching), for generic data and Gencompress for DNA, are the best performers among the compression algorithms we have used, although the difference in performance, as measured by statistical indexes, between them and the other algorithms depends critically on the data set and may not be as large as expected. PPMd used with UCD or NCD and UPGMA, on sequence data is very close, although worse, in performance with the alignment methods (less than 2% difference on the F-measure). Yet, it scales well with data set size and it can work on data other than sequences. In summary, our quantitative analysis naturally complements the rich theory behind USM and supports the conclusion that the methodology is worth using because of its robustness, flexibility, scalability, and competitiveness with existing techniques. In particular, the methodology applies to all biological data in textual format. The software and data sets are available under the GNU GPL at the supplementary material web page.</p

    The diagnostic usefulness of the combined COMPASS 31 questionnaire and electrochemical skin conductance for diabetic cardiovascular autonomic neuropathy and diabetic polyneuropathy.

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    The study investigated the diagnostic performance for diabetic cardiovascular autonomic neuropathy (CAN) and diabetic polyneuropathy (DPN) of the combined use of composite autonomic symptom score (COMPASS) 31, validated questionnaire for autonomic symptoms of CAN, and electrochemical skin conductance (ESC), proposed for detecting DPN and CAN. One-hundred and two participants with diabetes (age 57 ± 14 years, duration 17 ± 13 years) completed the COMPASS 31 before assessing cardiovascular reflex tests (CARTs), neuropathic symptoms, signs, vibratory perception threshold (VPT), thermal thresholds (TT), and ESC using Sudoscan. Two patterns were evaluated: (a) the combined abnormalities in both tests (COMPASS 31+ESC), and (b) the abnormality in COMPASS 31 and/or ESC (COMPASS 31 and/or ESC). CAN (≥1 abnormal CART) and confirmed CAN (≥2 abnormal CARTs) were present in 28.1% and 12.5%, DPN (two abnormalities among symptoms, signs, VPT, and TT) in 52%, abnormal COMPASS 31 (total weighted score &gt;16.44) in 48% and abnormal ESC (hands ESC &lt;50 μS and/or feet ESC &lt;70 μS) in 47.4%. Both the patterns—COMPASS 31+ESC and COMPASS 31 and/or ESC—were associated with CAN and DPN (P &lt; .01). COMPASS 31 and ESC reached a sensitivity of 75% and 83% for confirmed CAN, and a specificity of 65% and 67% for DPN. When combining the tests, the sensitivity for CAN rose by up to 100% for CAN and the specificity up to 89% for DPN. The combination of the tests can allow a stepwise screening strategy for CAN, by suggesting CAN absence with combined normality, and prompting to CARTs with combined abnormality

    Metodi e soluzioni per ambienti inclusivi. Esperienze didattiche dell'UniversitĂ  di Pavia in collaborazione con ANIE AssoAscensori

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    Questa pubblicazione raccoglie le esperienze di un triennio di attività svolte da un gruppo di ricercatori di Architettura Tecnica afferenti al Dipartimento di Ingegneria Civile e Architettura (DICAr) dell’Università di Pavia in collaborazione con ANIE AssoAscensori. Le idee, i progetti e i contenuti che emergono in questo lavoro, orientati alla diffusione di una cultura progettuale inclusiva e senza barriere (architettoniche e culturali) sia alla scala urbana sia alla scala del manufatto edilizio storico, sintetizzano perfettamente le tre missioni dell’Ateneo: didattica, ricerca e terza missione

    “Ri-Generiamoci”: un progetto per promuovere la Solidarietà Intergenerazionale nel settore della cura all’anziano

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    Ri-Generiamoci is one research-action project promoted and coordinated by INRCA (National Institute for the Retirement and Care of Aged People, based in Ancona as part of a Retirement and Care Institute with Scientific Purposes). Its aim is that of making teenagers and aged people relate to the topic of the care of the elders. Since this objective is vital to intergenerationalknowledge and understanding, some educational activities have been identified, so that their cognitive or emotional character could reveal effective.In fact, the project is based on the assumption that personal relationships and cooperation are the only way to foster solidarity, thus preventing intolerance and abuse. This project includes: 8th grade students, aged people living in a multipurpose facility (residential and quasi-residential), and associations of volunteers. It was born out of the necessity to provide a clear answer to the needs of a category of people that is overexposed to abuse,as stated in “Abuel: abuse of elder in Europe.” Moreover, it complies with the requests of those who made contact with the Abused Elder People Line (TAM TAM). Both Abuel and TAM TAM are initiatives undertaken by INRCA in the Marche region.Il progetto Ri-Generiamoci è una ricerca-azione promossa e coordinata dall’INRCA (Istituto Nazionale di Ricovero e Cura per Anziani, Istituto di Ricovero e Cura a Carattere Scientifico – IRCCS – con sede ad Ancona), con l’obiettivo di mettere in relazione adolescenti ed anziani rispetto ad una tematica, quella della cura degli anziani, con cui le nuove generazioni vengono sempre più raramente a contatto. Al fine di perseguire questo obiettivo, cruciale per stimolare la conoscenza e comprensione intergenerazionale, sono state individuate una serie di attività pedagogiche di tipo sia cognitivo sia emotivo-esperienziale, certi che il rapporto umano e la collaborazione siano le uniche strade percorribili per l’educazione alla solidarietà e la prevenzionedi atti di intolleranza e di maltrattamento. Questo progetto pilota,che coinvolge studenti di terza media, gli anziani ospiti di una struttura re-sidenziale e semi-residenziale nonché due associazioni di volontariato, nasce dalla volontà di proporre una risposta concreta e lungimirante alle esigenze della popolazione anziana fragile, spesso maltrattata e a rischio di abuso, così come emerso dallo studio “Abuel: abuse of elder in Europe” e dalle richieste avanzate da coloro che hanno fatto ricorso al Telefono AnzianiMaltrattati (TAM TAM), due recenti iniziative condotte dall’INRCA nella regione Marche

    Effect of Estradiol and Progesterone on ovine Amniotic Epithelial Cells

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    This study was designed to clarify Estradiol (E2) and Progesterone (P4) steroid effects on ovine Amniotic Epithelial Cells (oAECs) that has a conserved plasticity and highly self-renewable capacity (Parolini et al., Stem Cells, 26(2), 300–311, 2008; Barboni et al., Stem Cell Rev Rep, 10:725–741, 2014). Based on their conserved immunomodulatory properties, oAECs are suitable for allo and xeno-transplantation (Barboni et al., Cell Transplant, 21(11), 2377–2395, 2012; Muttini et al., Res Vet Sci, 94(1),158–169, 2013). To date, no information is present on the effects of prolonged steroid exposition on AECs. oAECs were cultured as previously reported (Barboni et al., Cell Transplant. 21(11), 2377–2395, 2012) and treated with 12.5μM and 25μM of E2 or P4 (Sigma-Aldrich, Milan, Italy), alone and in both combinations, for three passages. Untreated cells were marked control (CTR). At 70% confluency, cells were detached for doubling time (DT) evaluation. Cells at fourth passage were differentiated for 21 days in osteogenic media (DM) (Mattioli et al., Cell Biol Int 36(1):7-19, 2012) without steroid. Alizarin Red and Alcian-Blue (Sigma-Aldrich, Milano, Italy) stainings were performed. RNA and cDNA were obtained as previously reported (Barboni et al., Cell Transplant. 21(11), 2377–2395, 2012). Real Time for NANOG, SOX2 ,OCT4 stemness genes expression were performed by SensiFast SYBR (Bioline, Aurogene, Rome, Italy) using specific primers (Mattioli et al., Cell Biol Int. 36(1):7-19, 2012).The protocol was: 5 min at 95°C, 30 cycles at 95°C for 15 sec, 60°C for 30 sec, 72°C for 15 sec. Comparative Ct 2-ΔΔC(t) normalization to GAPDH was applied. IHC analyses were carried out for Cytokeratin 8 and αSMA expression as previously reported (Barboni et al. PLoS ONE 7(2): e30974, 2012). Data expressed as mean (±SD), compared by one-way ANOVA followed by Tukey’s test (GraphPad Prism 5). Significant values for P &lt; 0.05. Steroids treated ovine AECs proliferate with significant differences between concentrations. While P4 treated cells showed cuboidal shape and Cytokeratin expression until third passage, CTR and E2 treated cells showed a rapid downregulation of Cytokeratin and increased αSMA expression. oAECs with E2+P4 showed both cell type morphology. Steroids modified stemness genes based on the concentration. 12.5 μM E2, 25μM P4 and 25μM of both E2+P4 treatments maintained higher OCT4, NANOG and SOX2 expressions in treated cells despite their progressive downregulation in the CTR. Moreover, compared to CTR, after Alizarin staining, steroid pretreated cells suffered morphological changes under DM acquiring Alcian Blue-positive chondrogenic-like morphology. AECs stemness properties and plasticity can be modified by prolonged steroidal treatment. These data improve our knowledge, opening new prospective on oAEC use in stem cell-based therapy. Acknowledgments. Research supported by H2020-MSCA ITN EJD-REP BIOTECH 675526

    Substrate Type and Concentration Differently Affect Colon Cancer Cells Ultrastructural Morphology, EMT Markers, and Matrix Degrading Enzymes

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    : Aim of the study was to understand the behavior of colon cancer LoVo-R cells (doxorubicin-resistant) vs. LoVo-S (doxorubicin sensitive) in the initial steps of extracellular matrix (ECM) invasion. We investigated how the matrix substrates Matrigel and type I collagen-mimicking the basement membrane (BM) and the normal or desmoplastic lamina propria, respectively-could affect the expression of epithelial-to-mesenchymal transition (EMT) markers, matrix-degrading enzymes, and phenotypes. Gene expression with RT-qPCR, E-cadherin protein expression using Western blot, and phenotypes using scanning electron microscopy (SEM) were analyzed. The type and different concentrations of matrix substrates differently affected colon cancer cells. In LoVo-S cells, the higher concentrated collagen, mimicking the desmoplastic lamina propria, strongly induced EMT, as also confirmed by the expression of Snail, metalloproteases (MMPs)-2, -9, -14 and heparanase (HPSE), as well as mesenchymal phenotypes. Stimulation in E-cadherin expression in LoVo-S groups suggests that these cells develop a hybrid EMT phenotype. Differently, LoVo-R cells did not increase their aggressiveness: no changes in EMT markers, matrix effectors, and phenotypes were evident. The low influence of ECM components in LoVo-R cells might be related to their intrinsic aggressiveness related to chemoresistance. These results improve understanding of the critical role of tumor microenvironment in colon cancer cell invasion, driving the development of new therapeutic approaches

    Fetal alcohol spectrum disorders in pediatrics. FASD and the pediatrician

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    Fetal alcohol syndrome (FAS) is a complex and malformative condition due to the teratogenic effect of alcohol consumed during pregnancy. Several epidemiological studies have shown that maternal alcohol use during pregnancy is the most common preventable cause of mental retardation in childhood. The effects of alcohol on the fetus range from abortion to a spectrum of clinical manifestations called Fetal Alcohol Spectrum Disorders (FASD) that includes partial FAS (PFAS), neonatal Alcohol Related Birth Defects (ARBD) and Alcohol Related Neurodevelopmental Disorders (ARND) up to the most severe disease which is the so-called FAS
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