1,721,005 research outputs found
Protein Analysis by FT-IR/ATR Spectroscopy
No full textFourier transform infrared spectroscopy (FT-IR) is a powerful tool for the study of inorganic and organic materials. In the past years, many efforts have been put forward for the use of FT-IR in living cells and tissues, and as a diagnostic tool to study pathology in vivo, ex vivo, and in vitro, due to its peculiar advantages, which include high sensitivity, small volume of samples, fast acquisition time, and broad range of compounds that can be analyzed. In orthopedic field, tissues, cells, and exosomes have been studied for applications in cartilage and osteoarthritis. For this application, FT-IR allows a fingerprint of the analyzed material to be obtained, providing information on the biological molecules that are contained (i.e., proteins, lipids, nucleic acids), in terms of quantity and organization, furnishing important information for studies on tissue pathophysiology, disease progression, and therapeutic evaluation
NEW MOLECULES FOR BONE TISSUE REGENERATION
No full textThe invention relates to compounds of general formula (I) and pharmaceutically acceptable salts thereof: (I) wherein Ri is selected from an SCN- group or is an RCONH- group; in particular, where Ri = RCONH, R is selected from an aromatic benzene ring substituted with an SCN- group in the ortho, meta or para position, according to the following formula: SCN- or R is a C1 -C4 alkyl chain, substituted with an SCN- group; n can be equal to 0 or else 1. The invention also relates to the use of such compounds for the treatment of osteoporosis and in general of bone pathologies characterised by a progressive loss of bone mass, for example rheumatoid arthritis, hyperparathyroidism or bone tumour metastase
3D Printed Perfusable Renal Proximal Tubule Model With Different Extracellular Matrix Compositions
No full textCartilage and bone serum biomarkers as novel tools for monitoring knee osteochondritis dissecans treated with osteochondral scaffold
No full textKnee osteochondritis dissecans (OCD) is a focal disease of the joint characterized by modifications of bone and cartilage tissues. Biomimetic osteochondral scaffolds are used to restore these tissues. The aim of this prognostic prospective cohort study was to evaluate serum biomarkers of cartilage (fragments or propeptide of type II collagen: CTXII, C2C, and CPII) and bone (tartrate-resistant acid phosphatase (TRAP) 5b and osteocalcin (OC)) turnover during follow-up of patients treated with an osteochondral scaffold, to identify which were related to healing outcome and clinical score. We found that cartilage (CPII) and bone (OC) synthetic biomarkers were significantly increased during the first-year follow-up, while the respective degradative markers (CTXII, C2C, and TRAP5b) were not modulated. Only CTXII/CPII and C2C/CPII cartilage ratios were significantly modulated, evidencing a higher remodeling of cartilage compared to bone tissue. Cartilage and bone single biomarkers or ratios at one-year follow-up showed values close to or similar to those of healthy subjects. International Knee Documentation Committee (IKDC) score significantly increased from T0 to T2, while the Tegner score did not. Taking into consideration an IKDC score > 70 as clinical success, we found that all OCD cases with both CPII (> 300 pg/ml) and C2C/CPII (<0.35) presented IKDC scores of clinical success. OCD patients treated with an osteochondral scaffold showed an improvement at one-year follow-up, evidenced by both clinical and serum cartilage biomarkers. These data confirmed that cartilage and bone remodeling took place and showed that systemic biomarkers represent a sensitive tool for monitoring OCD patients during the follow-up
CCL20/CCR6 chemokine/receptor expression in bone tissue from osteoarthritis and rheumatoid arthritis patients: different response of osteoblasts in the two groups
No full textSubchondral bone remodeling in osteoarthritis (OA) and rheumatoid arthritis (RA) is mainly characterized by the formation of osteophytes/fibrosis and by the presence of infiltrating cells associated to bone resorption. In this study we analyzed CC (cysteine cysteine motif) chemokine ligand (CCL)20 and CC chemokine receptor (CCR)6 function in subchondral bone tissue and osteoblasts isolated from OA and RA patients. CCL20/CCR6 expression was evaluated by immunohistochemical techniques in bone tissue from OA and RA patients. CCL20-functional tests were performed on osteoblasts isolated from OA and RA patients to evaluate enzymatic response and cell proliferation. Moreover, we assessed Akt phosphorylation as the major signaling pathway for CCL20. In bone tissue biopsies we found that osteoblasts from both OA and RA patients expressed CCR6 while CCL20 was expressed only by RA osteoblasts. Both CCR6 and CCL20 were highly expressed in osteocytes and mononuclear cells from only RA patients. CCL20-stimulated OA osteoblasts showed a significant increase in beta-N-acetylhexosaminidase release compared to RA. Conversely, a significant increase in cellular proliferation was found only in CCL20-stimulated RA osteoblasts associated to Akt phosphorylation. These data were confirmed in bone tissue biopsies. This study demonstrates a different expression of CCL20-positive osteoblasts in OA versus RA disease that seem to be associated with the presence of infiltrating mononuclear cells. Moreover, CCL20 stimulation resulted in a greater proliferative response in RA osteoblasts compared to OA osteoblasts, mediated by Akt signaling, while OA osteoblasts showed increased enzymatic activity, thus suggesting a differential role of this chemokine in OA and RA
The regulation of cystathionine γ-lyase (CSE) gene expression in human primary osteoblasts from vertebral bone: a matter of gender?
No full textHydrogen sulfide (H2S) is endogenously generated by cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE). It acts as a gaseous mediator in multiple signaling pathways including those involved in bone metabolism. Previous studies indicate that its level in human body is critical to maintain bone homeostasis, so that its significant decrease was observed in post-menopausal osteoporosis.
Since CSE was recently found to majorly contribute to endogenous H2S production in primary osteoblasts, we are interested to study the regulation of its expression investigating CSE expression in different cell culture conditions and the activity of specific regulatory gene promoter regions. In particular, we focused on the issue regarding a gender-related H2S biosynthesis since, by using different experimental models, recent evidences support the interaction of CSE/H2S pathway with estrogen or androgen in specific districts including vascular and bone tissue.
For this study we used human primary osteoblasts (hOBs) obtained from male and female vertebral bone: they express comparable levels of CSE protein as demonstrated by Western blot analysis.
Bioinformatic analysis performed on the CSE gene promoter revealed the presence of putative Estrogen Responsive Elements, in addition to the Sp1 binding sites previously described.
In order to analyze the potential involvement of Estrogen Receptor alpha (ER) and SP1 in the CSE gene expression, a fragment of CSE genomic region (-592/+139), wich represents the core promoter, was cloned into the upstream of firefly luciferase gene in the pGL3-Basic vector (pGL3-731). The construct was transiently transfected into hOBs under different conditions. Measuring luciferase activity by Luc assay we showed that the (-592/+139) construct presents similar activity respect to pGL3-Basic in all hOBs analyzed, but was differently affected by co-transfection with ER and Sp1 expression vectors. Specifically, in all hOBs, exogenous Sp1 overexpression as well as estrogen exposure did not significantly alter the luciferase reporter activity. On the contrary, ER overexpression together 10 nM 17-estradiol treatment deeply increased promoter activity in female hOBs but not in male hOBs. In the next step, the functional significance of ER and Sp1 on CSE gene regulation was investigated by “in vivo” chromatin immunoprecipitation (ChIP) assay. For this purpose male and female hOBs were properly cultured and collected for ChIP assay using antibodies against hERα and hSp1, and combined with semi-quantitative PCR detection. ChIP analyses revealed that both Sp1 and ER were recruited into the proximal region of CSE promoter. However, the ER recruitment was stronger in female hOBs than in male hOBs.
In conclusion, we demonstrated, for the first time, that Estrogen Receptor alpha transcription factor regulates CSE promoter activity and is recruited at specific regulatory sites in hOBs.
We are now investigating i. the possibility that male and female hOBs differ in production of co-regulators of estrogen-mediated CSE transcription regulation, and ii. whether also in osteoprogenitors (such as mesenchymal stem cells, MSCs) CSE expression is affected by this estrogen dependent regulation. Even though preliminary, our results results open an interesting scenario for evaluating the sexual hormones impact on H2S production and on functional activity of CSE enzyme in the bone physiopathological context
Reinforcement of injectable hydrogels through melt electro-written structures: Influence of shape and pore size on the injection force
Full text linkHydrogels are commonly used for tissue engineering applications due to their high water content, biocompatibility, injectability, and ability to mimic the extracellular matrix of native tissues. However, their weak mechanical properties limit their use, especially in load-bearing applications. In this study, we developed fibrous architectures with a pre-defined shape using melt electro-writing (MEW) to strengthen injectable hydrogels. We assessed the injection forces required to successfully extrude the hydrogel reinforced with MEW-printed structures, varying their geometry (square/hexagonal pores) and pore sizes (0.6, 0.8, 1.0 mm) through needles having a size compatible with clinical applications. Our findings indicate that MEW structures with hexagonal pores exhibit a higher tensile modulus than those with square pores. Additionally, the injection forces required to extrude hydrogels embedding MEW structures through needles were greater for hexagonal pores. Thinner pores and smaller needle diameters resulted in higher injection forces; a few conditions among the ones tested were compatible with the limits defined by the EU ISO 7886–1:2018 standard. After injection and crosslinking, hydrogels reinforced with MEW structures showed improved mechanical properties (up to 6.34-fold), particularly when structures with hexagonal pores were used
In Situ Extrusion of Biomaterials Through an Arthroscopic Tool: Characterization and Numerical Analyses
No full textHigh Circulating Levels of IL-4 and IL-10 in Progressive Pseudorheumatoid Dysplasia Patient
No full textNo abstract availabl
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