Publications by authors named "TOURNIER P"

Aging is marked by a decline in tissue regeneration, posing significant challenges to an increasingly older population. Here, we investigate age-related impairments in calvarial bone healing and introduce a novel two-part rejuvenation strategy to restore youthful repair. We demonstrate that aging negatively impacts the calvarial bone structure and its osteogenic tissues, diminishing osteoprogenitor number and function and severely impairing bone formation.

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One of the most common shoulder injuries is the rotator cuff tear (RCT). The risk of RCTs increases with age, with a prevalence of 9.7% in those under 20 years old and up to 62% in individuals aged 80 years and older.

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Bioprinting is a booming technology, with numerous applications in tissue engineering and regenerative medicine. However, most biomaterials designed for bioprinting depend on the use of sacrificial baths and/or non-physiological stimuli. Printable biomaterials also often lack tunability in terms of their composition and mechanical properties.

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Osteoarthritis (OA) is the most common debilitating joint disease, yet there is no curative treatment for OA to date. Delivering mesenchymal stromal cells (MSCs) as therapeutic cells to mitigate the inflammatory symptoms associated with OA is attracting increasing attention. In principle, MSCs could respond to the pro-inflammatory microenvironment of an OA joint by the secretion of anti-inflammatory, anti-apoptotic, immunomodulatory and pro-regenerative factors, therefore limiting pain, as well as the disease development.

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The Notch pathway is an evolutionarily preserved signaling pathway involved in a variety of vital cell functions. Additionally, it is one of the key regulators of inflammation, and controls the differentiation and function of different cells. Moreover, it was found to be involved in skeletal development and bone remodeling process.

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Article Synopsis
  • Dynamic hydrogels are versatile materials with properties like self-healing and injectability, making them valuable for biomedical uses, but their performance can be limited by issues like swelling and instability.
  • Research focused on boronate ester-based hydrogels, which are formed through reactions between phenylboronic acid derivatives and diols, to address these challenges, although they struggle to form effectively at physiological pH.
  • The study identified a combination of Wulff-type PBA and glucamine as an effective method to create stable, minimally swelling hydrogels that are long-lasting, tunable in mechanical characteristics, and compatible with cells, showcasing their potential in medical applications.
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The cellular microenvironment plays a major role in the biological functions of cells. Thus, biomaterials, especially hydrogels, which can be design to mimic the cellular microenvironment, are being increasingly used for cell encapsulation, delivery, and 3D culture, with the hope of controlling cell functions. Yet, much remains to be understood about the effects of cell-material interactions, and advanced synthetic strategies need to be developed to independently control the mechanical and biochemical properties of hydrogels.

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Autologous bone grafts (BGs) remain the reference grafting technique in various clinical contexts of bone grafting procedures despite their numerous peri- and post-operative limitations. The use of allogeneic bone is a viable option for overcoming these limitations, as it is reliable and it has been widely utilized in various forms for decades. However, the lack of versatility of conventional allogeneic BGs (e.

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In skeletal surgical procedures, bone regeneration in irregular and hard-to-reach areas may present clinical challenges. In order to overcome the limitations of traditional autologous bone grafts and bone substitutes, an extrudable and easy-to-handle innovative partially demineralized allogenic bone graft in the form of a paste has been developed. In this study, the regenerative potential of this paste was assessed and compared to its clinically used precursor form allogenic bone particles.

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Finding alternative strategies for the regeneration of craniofacial bone defects (CSD), such as combining a synthetic ephemeral calcium phosphate (CaP) implant and/or active substances and cells, would contribute to solving this reconstructive roadblock. However, CaP's architectural features (i.e.

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The ion influx isotherms obtained by measuring unidirectional influx across root membranes with radioactive or stable tracers are mostly interpreted by enzyme-substrate-like modeling. However, recent analyses from ion transporter mutants clearly demonstrate the inadequacy of the conventional interpretation of ion isotherms. Many genetically distinct carriers are involved in the root catalytic function.

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The polypeptide of aa 130-230 of the G protein (G2Na) of respiratory syncytial virus (RSV) was fused to BB, the albumin-binding region of streptococcal G protein, producing BBG2Na, which induced protective immune responses in rodent models. Evaluation of the immune response in mice immunized with BBG2Na in the adjuvant alhydrogel revealed high amounts of interleukin (IL)-5 and some IL-4 in splenocytes restimulated in vitro. This is compatible with a Th2 response.

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An immune adherence hemadsorption test for the rapid group-specific identification of adenoviruses is described. The test was performed directly on the cell culture isolate in less than 1 h, by the sequential addition of the antiserum of any adenovirus serotype, complement, and then C3b receptor-rich human erythrocytes. Microscopic examination revealed the presence of erythrocytes adhering firmly to the infected cell sheet.

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An enzyme-linked immunosorbent assay (ELISA) for the detection of IgG and IgM antibodies against Mycoplasma pneumoniae, performed with commercial antigen and reagents, is compared with the complement fixation test (CF) in a serological study of 209 human sera. Concordant results were usually obtained by CF test and by IgG ELISA in sera from patients with recent M pneumoniae infection. In contrast, when used for an immunological survey of a general population, approximately 27% of the sera negative in the CF test were positive for IgG by the ELISA, and sera with low CF titres were found to have a broad range of IgG titre by the ELISA.

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Transformation of a steroidogenic mouse adrenal cell line (Y-1) by simian adenovirus SA7 produced a cell line with low apparent steroidogenic activity. The effect of ACTH and cholera toxin on cyclic AMP production was similar in both not transformed and virus-transformed cells and activity of cyclic AMP-dependent protein kinase was also similar in both cells. In transformed cells, cholesterol was metabolized to delta 5-3 beta-hydroxysteroids, mainly 20 alpha-dihydropregnenolone while in not transformed cells, the major metabolites were delta 4-3 ketosteroids (20 alpha-dihydro- and 11 beta-hydroxy-20 alpha-dihydroprogesterone).

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Simian adenovirus 7 gave an abortive infection in simian marmoset lymphoblastoid cells, B 95-8 and M 81 (transformed by Epstein Barr Virus) whereas non transformed simian lymphocytes could not replicate this virus. Electron dense incomplete particles with a lower density than standard virus in CsCl gradients were isolated. Virus yields were low and the percentage of cells containing viral antigen as measured by immunofluorescence was 0.

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Hemagglutination inhibition (HI), single radial hemolysis (SRH) and enzyme-linked immuno sorbent assay (ELISA), performed with commercial antigen and reagents are described and were compared in the three distinct situations that require rubella antibody detection. Determination of immunity status was carried out on 156 sera. A degree of correlation greater than 0.

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Seventy five patients referred with a diagnosis of pneumonia underwent transtracheal puncture. In 76% of cases this examination led to discovery of an organism in infected patients. In 50% of cases, the bacteriological diagnosis was sufficiently accurately oriented by direct examination to permit rapid and effective treatment.

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Simian adenovirus 7, either complete virus or its capsid subunits, agglutinates Rat (Sprague-Dowley) red blood cells in the presence of heterotypical antiserum. Haemagglutination takes place at 4 degrees C and room temperature. The antigen could not be eluted and its haemagglutinin properties are heat-stable.

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