Birth weight and characteristics of endothelial and smooth muscle cell cultures from human umbilical cord vessels

<p>Abstract</p> <p>Background</p> <p>Low birth weight has been related to an increased risk for developing high blood pressure in adult life. The molecular and cellular analysis of umbilical cord artery and vein may provide information about the early vascular characteristics of an individual. We have assessed several phenotype characteristics of the four vascular cell types derived from human umbilical cords of newborns with different birth weight. Further follow-up studies could show the association of those vascular properties with infancy and adulthood blood pressure.</p> <p>Methods</p> <p>Endothelial and smooth muscle cell cultures were obtained from umbilical cords from two groups of newborns of birth weight less than 2.8 kg or higher than 3.5 kg. The expression of specific endothelial cell markers (von Willebrand factor, CD31, and the binding and internalization of acetylated low-density lipoprotein) and the smooth muscle cell specific α-actin have been evaluated. Cell culture viability, proliferation kinetic, growth fraction (expression of Ki67) and percentage of senescent cells (detection of β-galactosidase activity at pH 6.0) have been determined. Endothelial cell projection area was determined by morphometric analysis of cell cultures after CD31 immunodetection.</p> <p>Results</p> <p>The highest variation was found in cell density at the confluence of endothelial cell cultures derived from umbilical cord arteries (66,789 ± 5,093 cells/cm²vs. 45,630 ± 11,927 cells/cm², p < 0.05). Morphometric analysis indicated that the projection area of the artery endothelial cells (1,161 ± 198 and 1,544 ± 472 μm², p < 0.05), but not those derived from the vein from individuals with a birth weight lower than 2.8 kg was lower than that of cells from individuals with a birth weight higher than 3.5 kg.</p> <p>Conclusion</p> <p>The analysis of umbilical cord artery endothelial cells, which demonstrated differences in cell size related to birth weight, can provide hints about the cellular and molecular links between lower birth weight and increased adult high blood pressure risk.</p

Histological study of human periodontal tissue following biologically oriented preparation technique (BOPT)

The aim of this study was to conduct histological analysis of a human tooth resected with the periodontal insertion apparatus intact following treatment using biologically oriented preparation technique (BOPT). This descriptive histological dento-periodontal study used an anterior tooth extracted with the surrounding periodontal tissues intact, following prosthetic restoration with BOPT. The sample patient was recruited from among those attending the Department of Dental Medicine at the Faculty of Medicine and Dentistry, University of Valencia (Spain). Eight serial sections of the restored tooth were processed. The relative location and histological characteristics of the cemented prosthetic crown, the dental tissues of the tooth prepared by BOPT technique, and the periodontal tissues were analyzed. Structural analysis of the neoformed junctional epithelium showed that the number of layers decrease apically until there was a single row of cells perfectly adhered to the acellular cementum, and beneath the epithelium a connective tissue evidently free from inflammation. The tissues of the neoformed periodontium (gingival ligament, sulcular epithelium, junctional epithelium) presented histologic normality. Biologically oriented preparation technique is a reliable alternative to conventional horizontal finish lines

Effect on osseointegration of two implant macro-designs : a histomorphometric analysis of bicortically installed implants in different topographic sites of rabbit?s tibiae

To evaluate the effect of two different implant macro-designs on the sequential osseointegration at bicortically installed implants in the rabbit tibia. A further aim is to compare the osseointegration at different topographic zones. 27 New Zealand rabbits were implemented. Two implants, one for each macro-design (Ticare Inhex® or Ticare Quattro®, Mozo-Grau, Valladolid, Spain), were randomly implanted in the diaphysis or metaphysis of each tibia. The flaps were sutured to allow a submerged healing. The animals were sacrificed after 2, 4 or 8 weeks. Ground sections were prepared and analyzed. No statistically significant differences were found between the two groups for newly formed bone in contact with the implant surface, being about 16%, 19% and 33% in both groups, after 2, 4, and 8 weeks of healing. Bone apposition was slightly higher in the diaphysis, reaching values of 36.4% in the diaphysis, and 29.3% in the metaphysis at 8 weeks of healing. It was observed that the implant position showed a statistical significance regarding BIC values at 4 and 8 weeks (p<0.05). Multivariate analysis fails to detect statistical significant differences for the interaction between implant designs and topographic site. Ticare Quattro® design had a slight better BIC values at diaphysis sites across healing stages, but without reaching a statistical significance. The both implant macro-designs provided similar degrees of osseointegration. Bone morphometry and density may affect bone apposition onto the implant surface. The apposition rates were slightly better in diaphysis compared to metaphysis

Alginate-Agarose Hydrogels Improve the In Vitro Differentiation of Human Dental Pulp Stem Cells in Chondrocytes. A Histological Study

[EN] Matrix-assisted autologous chondrocyte implantation (MACI) has shown promising results for cartilage repair, combining cultured chondrocytes and hydrogels, including alginate. The ability of chondrocytes for MACI is limited by different factors including donor site morbidity, dedifferentiation, limited lifespan or poor proliferation in vitro. Mesenchymal stem cells could represent an alternative for cartilage regeneration. In this study, we propose a MACI scaffold consisting of a mixed alginate-agarose hydrogel in combination with human dental pulp stem cells (hDPSCs), suitable for cartilage regeneration. Scaffolds were characterized according to their rheological properties, and their histomorphometric and molecular biology results. Agarose significantly improved the biomechanical behavior of the alginate scaffolds. Large scaffolds were manufactured, and a homogeneous distribution of cells was observed within them. Although primary chondrocytes showed a greater capacity for chondrogenic differentiation, hDPSCs cultured in the scaffolds formed large aggregates of cells, acquired a rounded morphology and expressed high amounts of type II collagen and aggrecan. Cells cultured in the scaffolds expressed not only chondral matrix-related genes, but also remodeling proteins and chondrocyte differentiation factors. The degree of differentiation of cells was proportional to the number and size of the cell aggregates that were formed in the hydrogels.This work was funded by the Ministry of Economy and Competitiveness of the Spanish Government (PID2019-106099RB-C42, MM) and by the Generalitat Valenciana, Spain (PROMETEO/2020/069, CC). CIBER-BBN and CIBER-ER are financed by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and the Instituto de Salud Carlos III, with assistance of the European Regional Development Fund.Oliver-Ferrándiz, M.; Milián, L.; Sancho-Tello, M.; Martín De Llano, JJ.; Gisbert-Roca, F.; Martínez-Ramos, C.; Carda, C.... (2021). Alginate-Agarose Hydrogels Improve the In Vitro Differentiation of Human Dental Pulp Stem Cells in Chondrocytes. A Histological Study. Biomedicines. 9(7):1-22. https://doi.org/10.3390/biomedicines9070834S1229

31 visiones actuales de la transparencia

Treinta y una aportaciones de autores nacionales y extranjeros sobre la transparencia de las instituciones públicas y de los sujetos obligados por la Ley 19/2013 de 9 de diciembre y el derecho de acceso a la información pública

La histología en tiempos de pandemia y más allá

Conferencia virtual brindada en el marco del I Congreso de Educación en Ciencias Biológicas, llevado a cabo los días 27 y 28 de noviembre de 2020 en la Facultad de Odontología de la Universidad Nacional de La Plata.Para acceder al video y para su mejor visualización, hacer clic en "Enlace externo".Facultad de Odontologí

Changes in the proteolytic activities of proteasomes and lysosomes in human fibroblasts produced by serum withdrawal, amino-acid deprivation and confluent conditions.

The contribution of the main proteolytic pathways to the degradation of long-lived proteins in human fibroblasts grown under different conditions was investigated. The effects of various commonly used pharmacological inhibitors of protein degradation were first analysed in detail. By choosing specific inhibitors of lysosomes and proteasomes, it was observed that together both pathways accounted for 80% or more of the degradation of cell proteins. With lysosomal inhibitors, it was found that serum withdrawal or amino-acid deprivation strongly stimulated macroautophagy but not other lysosomal pathways, whereas confluent conditions had no effect on macroautophagy and slightly activated other lysosomal pathways. Prolonged (24 h) serum starvation of confluent cultures strongly decreased the macroautophagic pathway, whereas the activity of other lysosomal pathways increased. These changes correlated with electron microscopic observations and morphometric measurements of lysosomes. With proteasomal inhibitors, it was found that, in exponentially growing cells in the absence of serum, activity of the ubiquitin-proteasome pathway increases, whereas under confluent conditions the contribution (in percentage) of proteasomes to degradation decreases, especially in cells deprived of amino acids. Interestingly, in confluent cells, the levels of two components of the 19 S regulatory complex and those of an interchangeable beta-subunit decreased. This was associated with a marked increase in the levels of components of PA28-immunoproteasomes. Thus confluent conditions affect proteasomes in a way that resembles treatment with interferon-gamma. Altogether, these results show that the activity of the various proteolytic pathways depends on the growth conditions of cells and will be useful for investigation of the specific signals that control their activity