3D bioprinted human cortical neural constructs derived from induced pluripotent stem cells

Bioprinting techniques use bioinks made of biocompatible non-living materials and cells to build 3D constructs in a controlled manner and with micrometric resolution. 3D bioprinted structures representative of several human tissues have been recently produced using cells derived by differentiation of induced pluripotent stem cells (iPSCs). Human iPSCs can be differentiated in a wide range of neurons and glia, providing an ideal tool for modeling the human nervous system. Here we report a neural construct generated by 3D bioprinting of cortical neurons and glial precursors derived from human iPSCs. We show that the extrusion-based printing process does not impair cell viability in the short and long term. Bioprinted cells can be further differentiated within the construct and properly express neuronal and astrocytic markers. Functional analysis of 3D bioprinted cells highlights an early stage of maturation and the establishment of early network activity behaviors. This work lays the basis for generating more complex and faithful 3D models of the human nervous systems by bioprinting neural cells derived from iPSCs

Introduzione alla Teoria Quantistica dei Campi: Spazi di Fock e il modello

La QFT è una teoria nata in ambito fisico per risolvere alcuni problematiche della teoria quantistica delle particelle, dando risultati sorprendenti. Nasce come teoria effettiva a cui fu successivamente necessario dare un rigore matematico. In generale le strutture matematiche teorizzate non risultano adeguate a modellare un ampio spettro di sistemi fisici. Esistono tuttavia dei modelli “giocattolo” perfettamente coerenti per i quali sono stati creati strumenti molto interessanti ed efficaci, come ad esempio gli spazi di Fock. In questa tesi oltre a una presentazione dettagliata degli spazi di Fock verrà descritto un esempio non banale della loro applicazione: il modello interattivo e ristretto ad una sola dimensione spazial

Effect on DNA relaxation of the single Thr718Ala mutation in human topoisomerase I: a functional and molecular dynamics study

The functional and dynamical properties of the human topoisomerase I Thr718Ala mutant have been compared to that of the wild-type enzyme using functional assays and molecular dynamics (MD) simulations. At physiological ionic strength, the cleavage and religation rates, evaluated on oligonucleotides containing the preferred topoisomerase I DNA sequence, are almost identical for the wild-type and the mutated enzymes, as is the cleavage/religation equilibrium. On the other hand, the Thr718Ala mutant shows a decreased efficiency in a DNA plasmid relaxation assay. The MD simulation, carried out on the enzyme complexed with its preferred DNA substrate, indicates that the mutant has a different dynamic behavior compared to the wild-type enzyme. Interestingly, no changes are observed in the proximity of the mutation site, whilst a different flexibility is detected in regions contacting the DNA scissile strand, such as the linker and the V-shaped α helices. Taken together, the functional and simulation results indicate a direct communication between the mutation site and regions located relatively far away, such as the linker domain, that with their altered flexibility confer a reduced DNA relaxation efficiency. These results provide evidence that the comprehension of the topoisomerase I dynamical properties are an important element in the understanding of its complex catalytic cycle

Collectiones medicinae

Места для инициалов пустые. На л. [1] маргиналии 15 или начала 16 век; Переплетено вместе с двумя медицинскими сочинениями 17 векаCIH 123; GW 862; IBP 189; Боброва 27; УС 89; H 806; BMC V344; Ce3 A-388; IGI 1459; BSB-Ink B-275Каталог инкунабул Научной библиотеки Томского университета 1Lichtenstädt J. R.ГПБ им. Салтыкова-Щедрина, Ленинград, СССРЭкслибрис: J. R. Lichtenstädt ; на корешке чернилами, скорописью заглавие, номер: XIV.6.39 и круглый синий ярлык без надписей;Надпись на экслибрисе зачеркнута, карандашом подписано: д. 122-124.4/15

Polyakov Effective Action from Functional Renormalization Group Equation

We discuss the Polyakov effective action for a minimally coupled scalar field on a two dimensional curved space by considering a non-local covariant truncation of the effective average action. We derive the flow equation for the form factor in $\int\sqrt{g}R c_{k}(\Delta)R$, and we show how the standard result is obtained when we integrate the flow from the ultraviolet to the infrared.Comment: 19 pages, 5 figure

The ACPATH Metric: Precise Estimation of the Number of Acyclic Paths in C-like Languages

NPATH is a metric introduced by Brian A. Nejmeh in [13] that is aimed at overcoming some important limitations of McCabe's cyclomatic complexity. Despite the fact that the declared NPATH objective is to count the number of acyclic execution paths through a function, the definition given for the C language in [13] fails to do so even for very simple programs. We show that counting the number of acyclic paths in CFG is unfeasible in general. Then we define a new metric for C-like languages, called ACPATH, that allows to quickly compute an very good estimation of the number of acyclic execution paths through the given function. We show that, if the function body does not contain backward gotos and does not contain jumps into a loop from outside the loop, then such estimation is actually exact

UN GENERATORE DI PETTINE DI FREQUENZE PER L’ECCITAZIONE DI RIVELATORI DI FOTONI A BASSA ENERGIA

Il lavoro qui presentato, che nasce dalla collaborazione tra l’LNTS (Laboratorio Nuove Tecnologie e Strumenti) dell’INGV e il Dipartimento di Fisica dell’Università di Roma “La Sapienza”, descrive lo strumento realizzato per fornire il pettine di frequenze atto ad eccitare un sistema sperimentale per otto risuonatori KID. In tale sistema il pettine di frequenze verrà traslato nella banda di frequenza dei KIDs (nell’ordine dei GHz) per poterne effettuare l’eccitazione e quindi riportato nella banda iniziale per effettuarne l’acquisizione e l’analisi

An albumin-derived peptide scaffold capable of binding and catalysis

We have identified a 101-amino-acid polypeptide derived from the sequence surrounding the IIA binding site of human albumin. The polypeptide contains residues that make contact with ligands as warfarin in the parent protein, and eight cysteine residues to form disulfide bridges, which stabilize the polypeptide structure. Seventy-four amino acids are located in six [alpha]-helical regions, with the remaining amino acids forming six connecting coil/loop regions. Codon usage optimization was used to express a GST fusion protein in E. coli in yields as high as 4 mg/l. This fusion protein retains its structural integrity and aldolase activity, the ability to direct the stereochemical outcome of a diketone reduction, and its binding capacity to warfarin and efavirenz. Notably, this newly cloned polypeptide represents a valuable starting point for the construction of libraries of binders and catalysts with improved proficiency