A bioprinted 3D gut model with crypt-villus structures to mimic the intestinal epithelial-stromal microenvironment

The intestine is a complex tissue with a characteristic three-dimensional (3D) crypt-villus architecture, which plays a key role in the intestinal function. This function is also regulated by the intestinal stroma that actively supports the intestinal epithelium, maintaining the homeostasis of the tissue. Efforts to account for the 3D complex structure of the intestinal tissue have been focused mainly in mimicking the epithelial barrier, while solutions to include the stromal compartment are scarce and unpractical to be used in routine experiments. Here we demonstrate that by employing an optimized bioink formulation and the suitable printing parameters it is possible to produce fibroblast-laden crypt-villus structures by means of digital light projection stereolithography (DLP-SLA). This process provides excellent cell viability, accurate spatial resolution, and high printing throughput, resulting in a robust biofabrication approach that yields functional gut mucosa tissues compatible with conventional testing techniques.Copyright © 2023 Elsevier B.V. All rights reserved

EXPLORACIONES EN ÑAWINPUKIO, AYACUCHO

El Instituto de Antropología de la Universidad de San Cristóbal de Huamanga desarrolló, entre los años 1963 y 1966, un Programa de Investigaciones Arqueológicas que tenía como finalidad el estudio de las sociedades prehispá- nicas desarrolladas en el actual departamento de Ayacucho, cuya área geográfica coincide con el área de influencia de dicha Universidad. Las investigaciones arqueológicas centraban su atención y preocupación en el esclarecimiento de “los modos de comportamiento social, con énfasis en el estudio de la definición de los rasgos culturales, la organización social, y los procesos de cambio” de los pueblos que vivieron y habitaron dentro de la zona de influencia en los tiempos prehispánicos. La organización y dirección del referido Programa de Investigaciones Arqueológicas estuvo a cargo del Dr. Luis G. Lumbreras, profesor de la Universidad de Huamanga en aquellos años

ARQUEOLOGÍA DE ÑAUPAS

Ñaupas es un yacimiento arqueológico ubicado en las cercanías del pueblo de Paqcha, dentro del distrito de Vinchos en el departamento de Ayacucho, sierra central del Perú. Culturalmente Ñaupas representa una unidad, por el conjunto de evidencias que hemos encontrado, pero se trata de dos conjuntos cercanos de estructuras que nos demuestran haber sido parte integrante de una población esparcida depositaria de una tradición cultural común

Controlling the Host-Guest Interaction Mode through a Redox Stimulus

A proof-of-concept related to the redox-control of the binding/releasing process in a host-guest system is achieved by designing a neutral and robust Pt-based redox-active metallacage involving two extended-tetrathiafulvalene (exTTF) ligands. When neutral, the cage is able to bind a planar polyaromatic guest (coronene). Remarkably, the chemical or electrochemical oxidation of the host-guest complex leads to the reversible expulsion of the guest outside the cavity, which is assigned to a drastic change of the host-guest interaction mode, illustrating the key role of counteranions along the exchange process. The reversible process is supported by various experimental data (1 H NMR spectroscopy, ESI-FTICR, and spectroelectrochemistry) as well as by in-depth theoretical calculations performed at the density functional theory (DFT) level

Bronchial responses to substance P after antigen challenge in the guinea-pig: in vivo and in vitro studies

The effect of antigen challenge on the airway responses to substance P and on the epithelial neutral endopeptidase (NEP) activity was investigated in aerosol sensitized guinea-pigs. In vivo, bronchial responses to aerosolized substance P were similar to the responses observed in antigen-challenged guinea-pigs and in the control groups. In contrast, when the guinea-pigs were pretreated with the NEP inhibitor, phosphoramidon, a significant increase in the airway responses to substance P was observed after antigen challenge in vivo. However, in vitro, the contractile responses of the tracheal smooth muscle to substance P were similar between groups of guinea-pigs, in respect to the presence or absence of the epithelium and/or phosphoramidon. Histological studies showed an accumulation of eosinophils in the tracheal submucosa after antigen challenge and intact epithelial cells. These results show that in vivo bronchial hyperresponsiveness to substance P after antigen challenge in the guinea-pig is not associated with increased responses of the smooth muscle to exogenous SP in vitro. In addition, the results with phosphoramidon suggest that loss of NEP activity cannot account for the in vivo bronchial hyperresponsiveness to substance P presently observed

Ptilomycalin A, crambescidin 800 and related new highly cytotoxic guanidine alkaloids from the starfishes Fromia monilis and Celerina heffernani

Two novel pentacyclic guanidine alkaloids, celeromycalin 3 and fromiamycalin 4, have been isolated from the New Caledonian starfishes Celerina heffernani and Fromia monilis, respectively. The new compounds exhibited an high cytotoxic activity like the previous crambescidins. These complex pentacyclic guanidines are typical sponges metabolites and their occurence in starfishes is noteworthy. Fromia monilis also contained the less active component 5, made up from an hydroxyspermidine residue linked to a long chain omega-hydroxyacid

Boot-insole effects on comfort and plantar loading at the heel and fifth metatarsal during running and turning in soccer

Plantar loading may influence comfort, performance and injury risk in soccer boots. This study investigated the effect of cleat configuration and insole cushioning levels on perception of comfort and in-shoe plantar pressures at the heel and fifth metatarsal head region. Nine soccer academy players (age 15.7 ± 1.6 years; height 1.80 ± 0.40 m; body mass 71.9 ± 6.1 kg) took part in the study. Two boot models (8 and 6 cleats) and two insoles (Poron and Poron/gel) provided four footwear combinations assessed using pressure insoles during running and 180° turning. Mechanical and comfort perception tests differentiated boot and insole conditions. During biomechanical testing, the Poron insole generally provided lower peak pressures than the Poron/gel insole, particularly during the braking step of the turn. The boot model did not independently influence peak pressures at the fifth metatarsal, and had minimal influence on heel loads. Specific boot-insole combinations performed differently (P < 0.05). The 8-cleat boot and the Poron insole performed best biomechanically and perceptually, but the combined condition did not. Inclusion of kinematic data and improved control of the turning technique are recommended to strengthen future research. The mechanical, perception and biomechanical results highlight the need for a multi-faceted approach in the assessment of footwear

Semiring and semimodule issues in MV-algebras

In this paper we propose a semiring-theoretic approach to MV-algebras based on the connection between such algebras and idempotent semirings - such an approach naturally imposing the introduction and study of a suitable corresponding class of semimodules, called MV-semimodules. We present several results addressed toward a semiring theory for MV-algebras. In particular we show a representation of MV-algebras as a subsemiring of the endomorphism semiring of a semilattice, the construction of the Grothendieck group of a semiring and its functorial nature, and the effect of Mundici categorical equivalence between MV-algebras and lattice-ordered Abelian groups with a distinguished strong order unit upon the relationship between MV-semimodules and semimodules over idempotent semifields.Comment: This version contains some corrections to some results at the end of Section

microRNAs and the evolution of complex multicellularity:Identification of a large, diverse complement of microRNAs in the brown alga Ectocarpus

There is currently convincing evidence that microRNAs have evolved independently in at least six different eukaryotic lineages: animals, land plants, chlorophyte green algae, demosponges, slime molds and brown algae. MicroRNAs from different lineages are not homologous but some structural features are strongly conserved across the eukaryotic tree allowing the application of stringent criteria to identify novel microRNA loci. A large set of 63 microRNA families was identified in the brown alga Ectocarpus based on mapping of RNA-seq data and nine microRNAs were confirmed by northern blotting. The Ectocarpus microRNAs are highly diverse at the sequence level with few multi-gene families, and do not tend to occur in clusters but exhibit some highly conserved structural features such as the presence of a uracil at the first residue. No homologues of Ectocarpus microRNAs were found in other stramenopile genomes indicating that they emerged late in stramenopile evolution and are perhaps specific to the brown algae. The large number of microRNA loci in Ectocarpus is consistent with the developmental complexity of many brown algal species and supports a proposed link between the emergence and expansion of microRNA regulatory systems and the evolution of complex multicellularity