Amine functionalization of cholecyst-derived extracellular matrix with generation 1 PAMAM dendrimer

This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Biomacromolecules, copyright © American Chemical Society after peer review. To access the final edited and published work, see http://pubs.acs.org/doi/pdf/10.1021/bm701055k.A method to functionalize cholecyst-derived extracellular matrix (CEM) with free amine groups was established in an attempt to improve its potential for tethering of bioactive molecules. CEM was incorporated with Generation-1 polyamidoamine (G1 PAMAM) dendrimer by using N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide and N-hydroxysuccinimide cross-linking system. The nature of incorporation of PAMAM dendrimer was evaluated using shrink temperature measurements, Fourier transform infrared (FTIR) assessment, ninhydrin assay, and swellability. The effects of PAMAM incorporation on mechanical and degradation properties of CEM were evaluated using a uniaxial mechanical test and collagenase degradation assay, respectively. Ninhydrin assay and FTIR assessment confirmed the presence of increasing free amine groups with increasing quantity of PAMAM in dendrimer-incorporated CEM (DENCEM) scaffolds. The amount of dendrimer used was found to be critical in controlling scaffold degradation, shrink temperature, and free amine content. Cell culture studies showed that fibroblasts seeded on DENCEM maintained their metabolic activity and ability to proliferate in vitro. In addition, fluorescence cell staining and scanning electron microscopy analysis of cell-seeded DENCEM showed preservation of normal fibroblast morphology and phenotype

Long-Term Outcome and Quality of Life in Patients Treated for Head and Neck Sarcoma during Pediatric Age: Considerations from a Series of 4 Cases

Pediatric sarcomas are rare malignancies accounting for about 10% of solid tumors in childhood. Sarcomas represent a heterogeneous group of malignancies, especially they include Rhabdomyosarcoma (RMS) and Non-Rhabdomyosarcoma Type Sarcomas (STSNR). Therapeutic management of pediatric sarcomas is challenging. Multidisciplinary approach including chemotherapy, surgery and radiotherapy is the treatment of choice. The correct management of affected patients can be demanding, especially in terms of preserving a good quality of life (QoL). In the present study we described our experience with a series of patients diagnosed with head and neck non-metastatic sarcoma between January 1995 and December 2020, referred to Pediatric Oncology or to Maxillo-Facial Surgery of University Hospital of Modena and Reggio Emilia.The survivors were asked to complete questionnaires on health-related quality of life (HRQoL; PedsQL and EORTC QLQ-H&N 43). We found satisfactory results in terms of global HRQoL; although outstanding issues persist, such as deterioration in masticatory function, and speech. Long-term sequelae of multimodality treatment may lead to both significant aesthetic-functional and psychosocial implications that need to be further investigate during the whole the care pathway

Tendon Fascicle-Inspired Nanofibrous Scaffold of Polylactic acid/Collagen with Enhanced 3D-Structure and Biomechanical Properties

Surgical treatment of tendon lesions still yields unsatisfactory clinical outcomes. The use of bioresorbable scaffolds represents a way forward to improve tissue repair. Scaffolds for tendon reconstruction should have a structure mimicking that of the natural tendon, while providing adequate mechanical strength and stiffness. In this paper, electrospun nanofibers of two crosslinked PLLA/Collagen blends (PLLA/Coll-75/25, PLLA/Coll-50/50) were developed and then wrapped in bundles, where the nanofibers are predominantly aligned along the bundles. Bundle morphology was assessed via SEM and high-resolution x-ray computed tomography (XCT). The 0.4-micron resolution in XCT demonstrated a biomimetic morphology of the bundles for all compositions, with a predominant nanofiber alignment and some scatter (50-60% were within 12° from the axis of the bundle), similar to the tendon microstructure. Human fibroblasts seeded on the bundles had increased metabolic activity from day 7 to day 21 of culture. The stiffness, strength and toughness of the bundles are comparable to tendon fascicles, both in the as-spun condition and after crosslinking, with moderate loss of mechanical properties after ageing in PBS (7 and 14 days). PLLA/Coll-75/25 has more desirable mechanical properties such as stiffness and ductility, compared to the PLLA/Coll-50/50. This study confirms the potential to bioengineer tendon fascicles with enhanced 3D structure and biomechanical properties

Creating Micro- and Nanostructures on Tubular and Spherical Surfaces

The authors developed a new technique to create micro- and nanometer scale structures on curved free-standing objects by combining embossing/imprinting lithography approaches with mechanical loadings on elastic films. Embossing/imprinting generates small structures and mechanical loading determines shape or geometry of the final object. As a result, a portion of the tubes with a radius between 0.5 and 3.5 mm and a portion of the spheres with a radius between 2.4 and 7.0 mm were fabricated with grating line features (period of 700 nm) and microlens array features (lens radius of 2.5 µm) atop, respectively. It was found that both static analyses and finite element models can give good estimates on the radii of those curved objects, based on the dimension of the two layers, loading format, as well as mechanic strains. Thus, good control over shape and dimension of the free-standing structure can be achieved

EFFECTS OF MONOCARBOXYLIC AND DICARBOXYLIC-ACIDS ON MYOSIN ATPASE ACTIVITY TESTED BY LUMINOMETRIC PROCEDURE

L(+)Lactic acid enhances myosin ATPase in vitro. Different organic acids were tested for activation of myosin ATPase activity. L(+)Lactic is more effective in stimulating ATPase than D(-)Lactic. D(+) and L(-)Malic acids were also effective at the concentration of 2.5 x 10(-2)-5.0 x 10(-2) mmoles/l. At 3.0 x 10(-2) mmoles/l concentration the following acids are activators: acetic, oxalic, malonic, oxaloacetic, pyruvic, glyoxylic, glycolic; succinic is an inhibitor and acetoacetic is without effect. The activation is not in relation with the pKa of these acids. The inhibitory effects of organic acids are evident at the concentration of 5.0 x 10(-2) mmoles/l. This inhibitory effect is linearly increasing with their pKa. The results are discussed in connection with the possible role of these metabolites in controlling not only ATPase activity towards splitting of ATP, but also in controlling the removal of its hydrolytic products

Orchidopessi videolaparoscopica sec. Fowler-Stephens. Trattamento di scelta per il testicolo endoaddominale alto.

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