Epigenetic Reprogramming and Somatic Cell Nuclear Transfer.

Epigenetics is an area of genetics that studies the heritable modifications in gene expression and phenotype that are not controlled by the primary sequence of DNA. The main epigenetic mechanisms are DNA methylation, post-translational covalent modifications in histone tails, and non-coding RNAs. During mammalian development, there are two global waves of epigenetic reprogramming.

Differentially methylated regions identified in bovine embryos are not observed in adulthood.

The establishment of epigenetic marks during the reprogramming window is susceptible to environmental influences, and stimuli during this critical stage can cause altered DNA methylation in offspring. In a previous study, we found that low levels of sulphur and cobalt (low S/Co) in the diet offered to oocyte donors altered the DNA methylome of bovine embryos. However, due to the extensive epigenetic reprogramming that occurs during embryogenesis, we hypothesized that the different methylation regions (DMRs) identified in the blastocysts may not maintain in adulthood.

Biomaterials and Adipose-Derived Mesenchymal Stem Cells for Regenerative Medicine: A Systematic Review.

The use of biological templates for the suitable growth of adipose-derived mesenchymal stem cells (AD-MSC) and "neo-tissue" construction has exponentially increased over the last years. The bioengineered scaffolds still have a prominent and biocompatible framework playing a role in tissue regeneration. In order to supply AD-MSCs, biomaterials, as the stem cell niche, are more often supplemented by or stimulate molecular signals that allow differentiation events into several strains, besides their secretion of cytokines and effects of immunomodulation.

Procaine and S-Adenosyl-l-Homocysteine Affect the Expression of Genes Related to the Epigenetic Machinery and Change the DNA Methylation Status of Cultured Bovine Skin Fibroblasts.

Cloning using somatic cell nuclear transfer (SCNT) has many potential applications such as in transgenic and genomic-edited animal production. Abnormal epigenetic reprogramming of somatic cell nuclei is probably the major cause of the low efficiency associated with SCNT. Strategies to alter DNA reprogramming in donor cell nuclei may help improve the cloning efficiency.

DNA methylation of the endogenous retrovirus Fematrin-1 in fetal placenta is associated with survival rate of cloned calves.

Introduction: The expression of retroviral envelope proteins in the placenta facilitates generation of the multinuclear syncytiotrophoblast as an outer cellular layer of the placenta by fusion of the trophoblastic cells. This process is essential for placenta development in eutherians and for successful pregnancy.

Methods: We tested the hypothesis that alterations in DNA methylation and gene expression profiles of the endogenous retroviruses (ERVs) and genes related to epigenetic reprogramming in placenta of cloned calves result in abnormal offspring phenotypes.

DNA methylation and functional characterization of the XIST gene during early embryo development in cattle.

XIST, in association with the shorter ncRNA RepA, are essential for the initiation of X chromosome inactivation (XCI) in mice. The molecular mechanisms controlling XIST and RepA expression are well characterized in that specie. However, little is known in livestock.

DNA methylation profile at a satellite region is associated with aberrant placentation in cloned calves.

Introduction: Cloning via somatic cell nuclear transfer (SCNT) has been associated with a variety of pathologies, primarily in the placenta, and these alterations may be associated with aberrant epigenetic reprogramming of the donor cell genome. We tested the hypothesis that DNA methylation patterns are not appropriately established after nuclear transfer and that those altered patterns are associated with specific aberrant phenotypes.

Methods: We compared global and specific placental DNA methylation patterns between aberrant and healthy SCNT-produced calves.

The Promising Applications of Stem Cells in the Oral Region: Literature Review.

Introduction: For a long time researchers have tried to find out a way to grow tissues back to the human body in order to solve transplantation problems by offering the unique opportunity to have their organs back, working properly, in search of life dignity.

Literature Review: Stem cells seem to be present in many other tissues than researchers had once thought; and in some specific sites they can be easily collected, without the need of expensive interventions. The oral cavity is one of these regions where their collection can be accomplished, with plenty of accessible sites enriched with these precious cells.

Evaluation of the nasal shape after orthognathic surgery.

Introduction: Patients with dentofacial deformities may benefit from orthognathic surgery in the maxilla. Maxillary osteotomy may include procedures in the bone, cartilaginous, and soft tissues of the nose, leading to shape alterations.

Objective: To evaluate the anatomic alterations of the nasal region in patients undergoing a Le Fort I osteotomy for advancement or superior impaction.

The influence of composite resin restorations and lining on radiographic diagnosis and decision-making: an in vitro investigation.

The objective of this study was to evaluate the influence of resin-based restorations on the interpretation of digital and conventional radiographic images and to correlate the proposed diagnosis with decision-making. Class II cavities were prepared in one of the proximal surfaces of extracted human molars. Teeth were divided into five groups (n = 10) according to the restoratives used: Natural Flow (NF) and Filtek Supreme (FS); Filtek Flow (FF) and FS; Tetric Flow (TF) and FS; Protect Liner F (PLF) and FS; and FS alone.

Lymphangioma mimicking apical periodontitis.

Introduction: Lymphangiomas mimicking apical periodontitis, usually found in soft tissue of children and infants younger than 2 years, are extremely rare in aged patients, particularly in bone tissues.

Methods: An 81-year-old woman was seen in a radiological service to undergo imaging studies for the placement of dental implants. A panoramic radiograph showed a radiolucent multilocular structure in the left mandibular molar region, where teeth #17 and #18 had previously been treated endodontically.

Correlation of the radiographic and morphological features of the dental follicle of third molars with incomplete root formation.

The objective of this study was to determine the correlation of the radiographic and morphological features of the dental follicle of unerupted third molars with incomplete root formation. A cross-sectional study was carried out with 56 patients (105 teeth) aged 13 to 24 years. Panoramic radiography was used to determine the stage of root formation to locate and measure pericoronal radiolucency.

Oral complaints in progressive systemic sclerosis: two cases report.

Progressive systemic sclerosis is a chronic sclerotic disease which causes diffuse, increased deposition of extracellular matrix in connective tissue with vascular abnormalities, resulting in tissue hypoxia. Aesthetic and facial dysfunction are followed by important oral and facial manifestation of disturbances such as xerostomia, the lack of saliva in the mouth, and its associated complications. Most clinical manifestations begin with tongue rigidity.

Eosinophilic granuloma in the jaws.

Eosinophilic granuloma is the most common expression of Langerhans cell histiocytosis and corresponds with typical bone lesions. This disease is of importance to dental professionals because early clinical signs can occur in the jaw and can cause extensive destruction of the periodontal tissues. Pathological fracture is an unusual finding.

Obstruction of the left ventricular outflow tract after mitral valvuloplasty with implantation of Gregori's ring.

Mitral valvuloplasty is efficient for repairing mitral valve disease with few complications. In some cases, obstruction of the left ventricular outflow tract may occur due to systolic anterior motion of the mitral valve. We report the case of a patient with this complication and a pressure gradient between the left ventricle and the aorta of 130 mm Hg after mitral valvuloplasty with implantation of a Gregori's ring.