Background
Parkinson’s disease (PD) is the second most common age-related neurodegenerative disorder. Levodopa (L-DOPA) remains the standard gold drug available for the treatment of PD. Curcumin has ...a wide range of pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, anti-amyloid, antitumor properties. Copolymers composed of poly(ethylene oxide) (PEO) and biodegradable polyesters like poly(ε-caprolactone) (PCL) that can self-assemble into nanoparticles (NP). This study describes the development of NH2-PEO-PCL diblock copolymer positively charged and modified by the addition of glutathione (GSH) on the outer surface, resulting in a synergistic delivery of L-DOPA and curcumin that would be able to pass the blood-brain barrier.
Methods
The NH2-PEO-PCL nanoparticles suspensions were prepared using a nanoprecipitation and solvent displacement method and were coated with GSH. NP was submitted to various characterizations assays, and to ensure the bioavailability, Vero and PC12 cells were treated with various concentrations of the loaded and unloaded NP to observe cytotoxicity.
Results
NP has successfully loaded L-DOPA and curcumin was stable after freeze-drying, capable of advancing into in vitro toxicity testing. After being treated up to 72 hours of various concentrations of L-DOPA and curcumin loaded NP Vero and PC12 cells, the viability of the treated cells maintained a high percentage indicating that the NPs are biocompatible.
Conclusions
NP consisting of NH2-PEO-PCL have been characterized as potential formulations for brain delivery of L-DOPA and curcumin, and obtained results also indicate that the developed biodegradable nanomicelles were blood compatible, presented low cytotoxicity even in longer exposure times.
Background: Tracheal lesions are pathologies derived from the most diverse insults that can result in a fatal outcome. Despite the number of techniques designed for the treatment, a limiting factor ...is the extent of the extraction. Therefore, strategies with biomaterials can restructure tissues and maintain the organ’s functionality, like decellularized Wharton’s jelly (WJ) as a scaffold. The aim is to analyze the capacity of tracheal tissue regeneration after the implantation of decellularized WJ in rabbits submitted to a tracheal defect. Methods: An in vivo experimental study was undertaken using twenty rabbits separated into two groups (n = 10). Group 1 submitted to a tracheal defect, group 2 tracheal defect, and implantation of decellularized WJ. The analyses were performed 30 days after surgery through immunohistochemistry. Results: Inner tracheal area diameter (p = 0.643) didn’t show significance. Collagen type I, III, and Aggrecan highlighted no significant difference between the groups (both collagens with p = 0.445 and the Aggrecan p = 0.4). Conclusion: The scaffold appears to fit as a heterologous implant and did not trigger reactions such as rejection or extrusion of the material into the recipient. However, these results suggested that although the WJ matrix presents several characteristics as a biomaterial for tissue regeneration, it did not display histopathological benefits in trachea tissue regeneration.
SARS-CoV-2 environmental monitoring can track the rate of viral contamination and can be used to establish preventive measures. This study aimed to detect by RT-PCR the presence of SARS-CoV-2 from ...inert surface samples in public health settings with a literature review about surface contamination and its burden on spread virus. Samples were collected from health settings in Curitiba, Brazil, between July and December 2020. A literature review was conducted using PRISMA. A total of 711 environmental surface samples were collected from outpatient areas, dental units, doctors' offices, COVID-19 evaluation areas, and hospital units, of which 35 (4.9%) were positive for SARS-CoV-2 RNA. The frequency of environmental contamination was higher in primary care units than in hospital settings. The virus was detected on doctors' personal items. Remarkably, the previously disinfected dental chair samples tested positive. These findings agree with those of other studies in which SARS-CoV-2 was found on inanimate surfaces. Detection of SARS-CoV-2 RNA on surfaces in public health settings, including those not meant to treat COVID-19, indicates widespread environmental contamination. Therefore, the intensification of disinfection measures for external hospital areas may be important for controlling community COVID-19 dissemination.
Periodontitis is a prevalent disease characterized by the loss of periodontal supporting tissues, bone, periodontal ligament, and cementum. The application of a bone tissue engineering strategy with ...Decellularized Human Amniotic Membrane (DAM) with adipose-derived stromal cells (ASCs) has shown to be convenient and valuable. This study aims to investigate the treatments of a rat periodontal furcation defect model with DAM, ASCs, and a mineralized extracellular matrix (ECM). Rat ASCs were expanded, cultivated on DAM, and with a bone differentiation medium for four weeks, deposited ECM on DAM. Periodontal healing for four weeks was evaluated by micro-computed tomography and histological analysis after treatments with DAM, ASCs, and ECM and compared to untreated defects on five consecutive horizontal levels, from gingival to apical. The results demonstrate that DAM preserves its structure during cultivation and healing periods, supporting cell attachment, permeation, bone deposition on DAM, and periodontal regeneration. DAM and DAM+ASCs enhance bone healing compared to the control on the gingival level. In conclusion, DAM with ASC or without cells and the ECM ensures bone tissue healing. The membrane supported neovascularization and promoted osteoconduction.
Background
Mesenchymal stem cells (MSCs) are undifferentiated cells and can be isolated from many tissues, including adipose tissue. MSCs neuronal differentiation ability has arisen interest in ...research with these cells in neurodegenerative diseases, such as Parkinson’s disease (PD). To differentiate MSCs in cells that produce dopamine that posteriorly potential to be a safe cell therapy for PD.
Methods
MSCs were isolated from adipose tissue, characterized by flow cytometry and trilineage differentiation, and cultivated seeded on natural functional biopolymer matrix (NFBX) to differentiate in neuronal precursors. Finally, a neural precursor was cultivated in the dopaminergic differentiation medium. The immunocytochemistry was performed with antibody anti-Nestin for precursor neural and antibodies anti-ß III-tubulin and hydroxylase tyrosine. Then, quantification of dopamine was made by the ELISA kit in the culture medium.
Results
The cytometric analysis of MSCs and the trilineage test to chondrocyte, osteocyte, and adipocyte demonstrated their pluripotency. Cells seeded and cultivated over NFBX have developed neurospheres, and their mechanical dissociated cells were Nestin positive. Dopaminergic differentiation was confirmed with positivity for ß-III tubulin and hydroxylase tyrosine. The dopamine concentration was very high in one sample (74.91 ng/mL). Without this sample, the media was 2.34 ± 2.13 ng/mL. The difference between dopamine concentrations was probably due to donors' metabolic characteristics.
Conclusions
The MSCs differentiated in neural precursor cells without genetic modification or growth factors, using only this NFBX. When these neural precursors were induced to differentiate, they were available to produce dopamine, demonstrating a functional neuronal differentiation.
Background
Considering the expressive number of individuals being diagnosed with diabetes worldwide, it is relevant to find medicines and treatments, in order to achieve diabetes complications, as ...diabetic retinopathy (DR) long-awaited regression and/or cure. The study aimed to evaluate cell therapy with human neural precursor cells (hNPCs) on induced diabetic retinopathy (DR) in Wistar rats.
Methods
Wharton's Jelly Mesenchymal stem cells (WJ-MSCs) were isolated, expanded, and seeded onto a biopolymer substrate without growth factors to develop neurospheres, then hNPCs were obtained and characterized by immunocytochemistry. The animals were divided into three groups; non-diabetic (ND) n = 4; diabetic without treatment (DM) n = 9; diabetic with cell therapy (DM + hNPCs) n = 9. Cells were transplanted by intravitreal injection (1 x 106 cel/µL) into each of Streptozotocin (STZ) induced diabetes rats. Evaluations by Optical Coherence Tomography (OCT) and Electroretinography (ERG) were done before and after diabetes induction and post cell therapy. Four weeks after treatment, eye enucleation allowed histopathological and immunohistochemistry (IHC) analysis.
Results
hNPCs increased the number of retina ganglion cells, ameliorated the photoreceptor layer, and decreased the microvessel points, evidenced by ERG, OCT, histopathological, and IHC findings. The most relevant differences in morphological analysis (treated vs untreated), exhibit the retinal improvement in many layers, notably in the retinal pigment epithelium and photoreceptors.
Conclusions
hNPCs reduced DR progression, as demonstrated by a neuroprotective effect and promotion of retinal regeneration.
This systematic review evaluated the transplantation of cells derived from adipose tissue for applications in dentistry. SCOPUS, PUBMED and LILACS databases were searched for in vitro studies and ...pre-clinical animal model studies using the keywords "ADIPOSE", "CELLS", and "PERIODONTAL", with the Boolean operator "AND". A total of 160 titles and abstracts were identified, and 29 publications met the inclusion criteria, 14 in vitro and 15 in vivo studies. In vitro studies demonstrated that adipose- derived cells stimulate neovascularization, have osteogenic and odontogenic potential; besides adhesion, proliferation and differentiation on probable cell carriers. Preclinical studies described improvement of bone and periodontal healing with the association of adipose-derived cells and the carrier materials tested: Platelet Rich Plasma, Fibrin, Collagen and Synthetic polymer. There is evidence from the current in vitro and in vivo data indicating that adipose-derived cells may contribute to bone and periodontal regeneration. The small quantity of studies and the large variation on study designs, from animal models, cell sources and defect morphology, did not favor a meta-analysis. Additional studies need to be conducted to investigate the regeneration variability and the mechanisms of cell participation in the processes. An overview of animal models, cell sources, and scaffolds, as well as new perspectives are provided for future bone and periodontal regeneration study designs.
Acellular amniotic membrane (AM) has been studied, with promising results on the reconstruction of lesioned tissues, and has become an attractive approach for tracheal repair. This study aimed to ...evaluate the repair of the trachea with human umbilical cord mesenchymal stem cells (hucMSCs) differentiated in chondrocytes, grown on an experimental model. Tracheal defects were induced by surgical tracheostomy in 30 New Zealand rabbits, and the acellular amniotic membrane, with or without cells, was covering the defect. The hucMSCs were isolated and cultivated with chondrogenic differentiation over the culture of 14 days, and then grown on the AM. In this study, the AM was biocompatible and hucMSCs differentiated into chondrocytes. Our results demonstrated an important role for AM with cultured cells in the promotion of immature collagen, known to produce tissue regeneration. In addition, cartilaginous tissue was found at the tracheal defects, demonstrated by immunohistology results. This study suggests that this biomaterial implantation can be an effective future therapeutic alternative for patients with tracheal injury.
Most transplanted organs are obtained from brain-dead donors. Inflammation results in a higher rate of rejection.
The objective of this animal model of brain death (BD) was to evaluate the effect of ...the progressive institution of volume expansion, norepinephrine, and combined hormone therapy on clinical, laboratory, and histological aspects.
Twenty rabbits were divided: A (control), B (induction of BD + infusion of crystalloid), C (BD + infusion of crystalloid and noradrenaline (NA)), and D (BD + infusion of crystalloid + vasopressin + levothyroxine + methylprednisolone + NA). The animals were monitored for four hours with consecutives analysis of vital signs and blood samples. The organs were evaluated by a pathologist.
In Group D, we observed fewer number and lesser volume of infusions (
= 0.032/0.014) when compared with groups B and C. Mean arterial pressure levels were higher in group D when compared with group B (
= 0.008). Group D had better glycemic control when compared with group C (
= 0.016). Sodium values were elevated in group B in relation to groups C and D (
= 0.021). In Group D, the organ perfusion was better.
The optimized strategy of management of BD animals is associated with better hemodynamic, glycemic, and natremia control, besides reducing early signs of ischemia.
To investigate the effect of transplantation of stem cells from the bone marrow mononuclear cells (BMMC) associated with 15d-PGJ2-loaded nanoparticles in a rat model of chronic MI. Chronic myocardial ...infarction (MI) was induced by the ligation of the left anterior descending artery in 40 male Wistar rats. After surgery, we transplanted bone marrow associated with 15d-PGJ2-loaded nanoparticle by intramyocardial injection (10
cells/per injection) seven days post-MI. Myocardial infarction was confirmed by echocardiography, and histological analyses of infarct morphology, gap junctions, and angiogenesis were obtained. Our results from immunohistochemical analyses demonstrated the presence of angiogenesis identified in the transplanted region and that there was significant expression of connexin-43 gap junctions, showing a more effective electrical and mechanical integration of the host myocardium. This study suggests that the application of nanoparticle technology in the prevention and treatment of MI is an emerging field and can be a strategy for cardiac repair.
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