65 research outputs found
Calcium Sulfate and Platelet-Rich Plasma make a novel osteoinductive biomaterial for bone regeneration
BACKGROUND: With the present study we introduce a novel and simple biomaterial able to induce regeneration of bone. We theorized that nourishing a bone defect with calcium and with a large amount of activated platelets may initiate a series of biological processes that culminate in bone regeneration. Thus, we engineered CS-Platelet, a biomaterial based on the combination of Calcium Sulfate and Platelet-Rich Plasma in which Calcium Sulfate also acts as an activator of the platelets, therefore avoiding the need to activate the platelets with an agonist. METHODS: First, we tested CS-Platelet in heterotopic (muscle) and orthotopic (bone) bone regeneration bioassays. We then utilized CS-Platelet in a variety of dental and craniofacial clinical cases, where regeneration of bone was needed. RESULTS: The heterotopic bioassay showed formation of bone within the muscular tissue at the site of the implantation of CS-Platelet. Results of a quantitative orthotopic bioassay based on the rat calvaria critical size defect showed that only CS-Platelet and recombinant human BMP2 were able to induce a significant regeneration of bone. A non-human primate orthotopic bioassay also showed that CS-Platelet is completely resorbable. In all human clinical cases where CS-Platelet was used, a complete bone repair was achieved. CONCLUSION: This study showed that CS-Platelet is a novel biomaterial able to induce formation of bone in heterotopic and orthotopic sites, in orthotopic critical size bone defects, and in various clinical situations. The discovery of CS-Platelet may represent a cost-effective breakthrough in bone regenerative therapy and an alternative or an adjuvant to the current treatments
Aberrant epigenetic changes and gene expression in cloned cattle dying around birth
<p>Abstract</p> <p>Background</p> <p>Aberrant reprogramming of donor somatic cell nuclei may result in many severe problems in animal cloning. To assess the extent of abnormal epigenetic modifications and gene expression in clones, we simultaneously examined DNA methylation, histone H4 acetylation and expression of six genes (<it>β-actin</it>, <it>VEGF</it>, <it>oct4</it>, <it>TERT</it>, <it>H19 </it>and <it>Igf2</it>) and a repetitive sequence (<it>art2</it>) in five organs (heart, liver, spleen, lung and kidney) from two cloned cattle groups that had died at different stages. In the ED group (early death, n = 3), the cloned cattle died in the perinatal period. The cattle in the LD group (late death, n = 3) died after the perinatal period. Normally reproduced cattle served as a control group (n = 3).</p> <p>Results</p> <p>Aberrant DNA methylation, histone H4 acetylation and gene expression were observed in both cloned groups. The ED group showed relatively fewer severe DNA methylation abnormalities (p < 0.05) but more abnormal histone H4 acetylations (p < 0.05) and more abnormal expression (p < 0.05) of the selected genes compared to the LD group. However, our data also suggest no widespread gene expression abnormalities in the organs of the dead clones.</p> <p>Conclusion</p> <p>Deaths of clones may be ascribed to abnormal expression of a very limited number of genes.</p
Tailored treatment including radical prostatectomy and radiation therapy + androgen deprivation therapy versus exclusive radical prostatectomy in high-risk prostate cancer patients: results from a prospective study
Purpose To evaluate outcomes of patients with high risk prostate cancer (PCa) who underwent radical prostatectomy (RP) in a context of a multidisciplinary approach including adjuvant radiation (RT) + androgen deprivation therapy (ADT). Matherials and Methods 244 consecutive patients with high risk localized PCa underwent RP and bilateral extended pelvic lymph node dissection at our institution. Adjuvant RT + 24 months ADT was carried out in subjects with pathological stage ≥ T3N0 and/or positive surgical margins or in patients with local relapse. Results After a median follow-up was 54.17 months (range 5.4-117.16), 13 (5.3%) subjects had biochemical progression, 21 (8.6%) had clinical progression, 7 (2.9%) died due to prostate cancer and 15 (6.1%) died due to other causes. 136 (55.7%) patients did not receive any adjuvant treatment while 108 (44.3%) received respectively adjuvant or salvage RT+ADT. Multivariate Cox proportional hazard analysis showed that pre-operative PSA value at diagnosis is a significant predictive factor for BCR (HR: 1.04, p < 0.05) and that Gleason Score 8-10 (HR: 2.4; p<0.05) and PSMs (HR: 2.01; p < 0.01) were significant predictors for clinical progression. Radical prostatectomy group was associated with BPFS, CPFS, CSS and OS at 5-years of 97%, 90%, 95% and 86% respectively, while adjuvant radiation + androgen deprivation therapy group was associated with a BPFS, CPFS and CSS at 5-years of 91%, 83%, 95% and 88%, without any statistical difference. Conclusions Multimodality tailored treatment based on RP and adjuvant therapy with RT+ADT achieve similar results in terms of OS after 5-years of follow-up
Effect of heparin derived fractions on the proliferation and protein synthesis of cells in culture.
We investigated the effect of sulfated oligosaccharides derived from depolymerization of heparin on the proliferation and protein synthesis of smooth muscle cells (SMC), hamster kidney (BHK-21) and lung (V-79) fibroblasts, rat hepatoma cells (FAO) and human promyelocytes (HL-60). BHK-21 and FAO showed the highest sensitivity to heparin; V-79 and HL-60 cells were completely resistant. LMWH (Low Molecular Weight Heparin) (MW 4.5 kD) was as effective as unfractionated heparin in reducing cell proliferation. The oligo-derivative 381/1 (MW 2 kD) was effective only on FAO and BHK-21 cells; oligo-derivative 381/2 (MW 1KD) had a negligible effect. The anti-proliferative effect was associated with an increased secretion of some protein classes. This effect was not present in heparin-resistant cells. In conclusion when the molecular size of heparin derivative is reduced below 2 kD (i.e. the size of a hexasaccharide) the anti-proliferative activity decreases dramatically
Effect of the desulfation of heparin on its anticoagulant and anti-proliferative activity
Some glycosaminoglycans (GAGs), such as heparin and heparin-like compounds inhibit the proliferation of several cell types, including smooth muscle cells, cervical epithelial cells and fibroblasts (1-3). In order to establish which domain of the hepar-in molecule is specifically responsible for the anti-proliferative activity, several strategies have been adopted such as: chemical modification or fractionation of the heparin molecule into low molecular weight fragments or synthesis of oligosaccharides with a defined chemical structure (4-6). In the present study we attempted to determine the role of N- and 0- linked sulfate groups on the anti-proliferative and anticoagulant effect of heparin. To that purpose we modified the molecule to produce N-desulfated, 0-desulfated compounds. The anti-proliferative activity of these modified heparins was compared to that of low molecular weight heparins obtained by depolymerization, heparan sulfate as N-acetylated compound with glucuronic acid and heparin. Since the anti-proliferative effect of heparin depends also on the cell type, we used two different cell types: BHK-21 (hamster fibroblasts) and human arterial SMC (smooth muscle cells), that were found to exhibit a high or intermediate sensitivity to heparin (3,7)
Modulation of the synthesis of apolipoproteins in rat hepatoma cells.
The present study was designed to investigate whether plasma lipoproteins and albumin can affect the basal synthetic rate of apolipoproteins in differentiated rat hepatoma cells (Fao) incubated in serum-free medium. The synthesis of apolipoproteins was measured by the incorporation of [35S]methionine into medium lipoproteins isolated by density gradient ultracentrifugation. Under all the experimental conditions used, Fao cells synthesized almost exclusively apolipoprotein E. When cells were incubated in the presence of 5-10% rat plasma the synthesis of apolipoprotein E increased 2-3-fold; lipoprotein-deficient serum had a negligible effect. Fatty acid-poor bovine serum albumin (BSA), which had been found to reduce very-low-density lipoprotein secretion in isolated rat hepatocytes, did not modify the synthesis of apolipoprotein E. When Fao cells were incubated in medium containing rat plasma lipoprotein fractions, the synthesis of apolipoprotein E increased. The d less than 1.090 g/ml plasma lipoprotein fraction had the major stimulatory effect. Increased apolipoprotein E synthesis was observed when cells were incubated in the presence of lipids extracted from rat plasma lipoproteins. These results suggest that the intracellular accumulation of lipoprotein-lipids plays an important role in regulating apolipoprotein E synthesis in Fao cells
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