Tissue engineering offers attractive strategies to develop three-dimensional scaffolds mimicking the complex hierarchical structure of the native bone. The bone is formed by cells incorporated in a ...molecularly organized extracellular matrix made of an inorganic phase, called biological apatite, and an organic phase mainly made of collagen and noncollagenous macromolecules. Although many strategies have been developed to replicate the complexity of bone at the nanoscale in vitro, a critical challenge has been to control the orchestrated process of mineralization promoted by bone cells in vivo and replicate the anatomical and biological properties of native bone. In this study, we used type I collagen to fabricate mineralized scaffolds mimicking the microenvironment of the native bone. The sulfated polysaccharide κ-carrageenan was added to the scaffolds to fulfill the role of noncollagenous macromolecules in the organization and mineralization of the bone matrix and cell adhesion. Scanning electron microscopy images of the surface of the collagen/κ-carrageenan scaffolds showed the presence of a dense and uniform network of intertwined fibrils, while images of the scaffolds’ lateral sides showed the presence of collagen fibrils with a parallel alignment, which is characteristic of dense connective tissues. MC3T3-E1 osteoblasts were cultured in the collagen scaffolds and were viable after up to 7 days of culture, both in the absence and in the presence of κ-carrageenan. The presence of κ-carrageenan in the collagen scaffolds stimulated the maturation of the cells to a mineralizing phenotype, as suggested by the increased expression of key genes related to bone mineralization, including alkaline phosphatase (Alp), bone sialoprotein (Bsp), osteocalcin (Oc), and osteopontin (Opn), as well as the ability to mineralize the extracellular matrix after 14 and 21 days of culture. Taken together, the results described in this study shed light on the potential use of collagen/κ-carrageenan scaffolds to study the role of the structural organization of bone-mimetic synthetic matrices in cell function.
The notes I share in this article are the result of research conducted within the framework of the Doctoral Program in Rule of Law and Global Governance at the University of Salamanca. This research, ...based on a queer theoreticalepistemological approach, seeks to analyse and bring together the Spanish and Brazilian legal overviews regarding the recognition of trans rights, in view of reconstructing policies that contemplate the demands of trans movements. The starting point for my research is a depathologising and human rights perspective. In the first part of this article I present the content of my investigation as well as its delimitation, object and objectives. Then, I address the difficulties that arise when bringing a queer analysis closer to the study of legislation, case law and public policies - as well as the strategies that can be developed from that. Finally, I present a series of suggestions to queer the study of law; that is, how to combine research methods to encompass different objectives and favour a trans/disciplinary dialogue, as well as how to embrace existing contradictions in a critical legal investigation.
Little is known regarding the prognostic implications of variant histology in upper tract urothelial carcinoma (UTUC). We sought to evaluate the impact of variant histology UTUC on patient survival ...outcomes at our institution.
We identified 705 patients who underwent nephroureterectomy for UTUC at our institution between January 1995 and December 2018. We tested the association between variant histology and cancer-specific survival (CSS) and overall survival (OS) using separate multivariable Cox models after adjusting for pathological stage.
Forty-seven patients (6.7%) had variant histology, with prevalence increasing over time (p=0.003). Other demographic and surgical characteristics were similar between variant histology and pure urothelial carcinoma groups. While patients with variant histology were more likely to receive neoadjuvant chemotherapy (38% vs 15%, p <0.001), they were also more likely to have a higher pathological T stage (p <0.001). Variant histology was associated with significantly worse CSS (HR: 2.14; 95% CI 1.33, 3.44; p=0.002) and OS (HR: 1.74; 95% CI 1.15, 2.63; p=0.008). After adjusting for pathological T stage, variant histology was not significantly associated with CSS (HR: 1.17; 95% CI 0.72, 1.89; p=0.5) or OS (HR: 1.20; 95% CI 0.79, 1.84; p=0.4).
Variant histology UTUC is associated with advanced stage and poor survival, and could serve as a useful biomarker for high-risk disease when pathological stage is unknown. However, the inferior CSS and OS with variant histology can be explained by the higher tumor stage on nephroureterectomy. Thus, finding variant histology on surgical pathology does not provide additional prognostic information beyond stage.
Leptospirosis is an emerging zoonotic disease caused by bacteria of the genus
Leptospira
. Wild animals may present acute disease or become chronic hosts. The present study aimed to identify
...Leptospira
spp. infection and determine circulating serogroups in free-ranging sambar deer (
Rusa unicolor
) in a fragment of peri-urban tropical forest in northeastern Brazil. Blood samples were collected and subjected to microscopic agglutination testing (MAT) and PCR analysis (genes
lipL32
and
secY
). Anti-
Leptospira
antibodies were detected in 60% of the animals tested, with serogroups Cynopteri (33.4%), Hebdomadis (22.2%) and Grippotyphosa (22.2%) identified as most prevalent. DNA corresponding to the pathogenic species
Leptospira interrogans
was detected in 2/15 (13.3%) of the samples tested. Sambar deer experience a high level of exposure to
Leptospira
spp. in our epidemiological setting. It is important to emphasize the implementation of effective measures (i.e., maintaining habitats and reducing human contact) for the conservation of endangered species.
The success of a biomaterial relies on an appropriate interaction between the surface of that biomaterial and the surrounding environment; more specifically, the success of a biomaterial depends on ...how fluids, proteins, and cells interact with the foreign material. For this reason, the surface properties of biomaterial, such as composition, charge, wettability, and roughness, must be optimized for a desired application to be achieved. In this review we highlight different bioinspired approaches that are used to manipulate and fine-tune the interfacial properties of biomaterials. Inspired by noteworthy natural processes, researchers have developed materials with a functional anatomy that range from hierarchical hybrid structures to self-cleaning interfaces. In this review we focus on (1) the creation of particles and modified surfaces inspired by the structure and composition of biogenic mineralized tissues, (2) the development of biofunctional coatings, (3) materials inspired by biomembranes and proteins, and (4) the design of superwettable materials. Our intention is to point out different bioinspired methodologies that have been used to design materials for biomedical applications and to discuss how interfacial properties modified by manipulation of these materials determine their final biological response. Our objective is to present future research directions and to highlight the potential of bioinspired materials. We hope this review will provide an understanding of the interplay between interfacial properties and biological response so that successful biomaterials can be achieved.
The research for alternative irrigating solutions is ongoing, since no “ideal” solution has yet been found. Octenidine dihydrochloride (OCT) has been indicated as an endodontic irrigant because it ...has adequate antimicrobial and biological properties. The present study aimed to assess the effects of OCT on proliferation, migration, and induction of the osteogenic phenotype of stem cells from human dental pulp and apical papilla.
Cells were collected from human third molars and exposed to different doses of OCT, chlorhexidine (CHX), sodium hypochlorite (NaOCl), and ethylenediaminetetraacetic acid (EDTA) to determine cell viability by alamarBlue assay; proliferation by bromodeoxyuridine incorporation; migration by the Transwell assay; alkaline phosphatase activity by thymolphthalein release; and production of mineralized nodules by alizarin red staining. The results were analyzed by 1- or 2-way analysis of variance and Tukey (α = .05).
CHX promoted lower cell viability, followed by OCT, NaOCl, and EDTA, especially at intermediate doses (P < .05). Cells exposed to CHX had less proliferation than the other groups (P < .05). The Transwell assay revealed no differences among OCT, EDTA, and culture medium (control group) (P > .05). OCT and EDTA induced greater migration than CHX and NaOCl (P < .05). OCT and EDTA induced higher alkaline phosphatase activity than NaOCl and CHX (P < .05). No difference was detected among the groups using alizarin red staining (P > .05).
OCT induced high migration, proliferation, and alkaline phosphatase activity of stem cells from human dental pulp and apical papilla, which could be advantageous for regenerative endodontic procedures.
Osteoma is a benign tumor of the bones, which can be classified as central or peripheral. The occurrence in the jawbones is uncommon, but when it occurs, there is a greater prevalence of the ...mandible. The etiology is still unknown, and the hypothesis of its development is debated.
A 35-year-old Caucasian man presenting a tumor lesion in the right jawbone that had been growing for 8 years sought medical service complaining of speaking impairment. According to the patient, the tumor appeared shortly after a minor trauma caused by tooth extraction. The diagnosis of the lesion was made through clinical, radiographic, and histological methods, and the surgical treatment was successful and satisfactory for the patient as well as the surgical team, despite a short follow-up.
Etiopathogenesis of osteoma is not determined in the majority of cases. In the present report, it was possible to hypothesize the association between a minor trauma and the development of the tumor, reinforcing the reactive theory of tumor development. The uncommon location of the osteoma, as well the possibility of identifying the possible cause of the lesion, makes this case particularly interesting.
Limited information exists on the potential link between levels of mindfulness and cognitive performance in seniors with low education. This cross-sectional study aims to explore the association ...between mindfulness levels and cognitive performance in older adults with different years of education. Participants were grouped by education levels and assessed for cognitive performance (ACE-R; Digit Span test), levels of mindfulness (Langer Mindfulness Scale-21), and depressive symptoms (Geriatric Depression Scale-15). Group comparisons, correlations, and linear and logistic regression analyses were conducted (p < .05). Cognitive performance, mindfulness levels, and depressive symptoms differed between groups, and correlations were found between mindfulness levels, ACE-R, and Digit Span scores. After controlling for education, the association between mindfulness levels and ACE-R performance remained significant. Logistic regression revealed that higher education and mindfulness levels increased the likelihood of scoring above the ACE-R cut-off. This study underscores the association between levels of mindfulness and cognitive performance in older adults.
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