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1.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 69(2): 272-278, Feb. 2023. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1422634

ABSTRACT

SUMMARY OBJECTIVE: One of the most important factors that adversely affects the outcome of peripheral nerve surgery is the formation of epineural and extraneural scar tissue after surgery. Many surgical methods and pharmacological and chemical agents have been used to prevent the formation of epineural scar tissue, but satisfactory results have not been achieved in clinical applications. The purpose of this study was to investigate the combined effect of fat graft and platelet-rich fibrin on the formation of epineural scar tissue and on nerve healing in the mature rat model. METHODS: A total of 24 female Sprague-Dawley rats were used. A circumferential segment of epineurium was excised from both bilateral sciatic nerves. The epineurectomized right nerve segment was wrapped with a combination of fat graft and platelet-rich fibrin (experimental group), while the left nerve segment did not receive any surgical procedure other than the epineurectomy (sham group). Notably, 12 randomly selected rats were sacrificed in the fourth week for histopathological examination of early results. The other 12 rats were sacrificed in the eighth week for late results. RESULTS: The formation of fibrosis, inflammation, and myelin degeneration were less common in the experimental group, while nerve regeneration was found to be higher at both 4 and 8 weeks. CONCLUSION: The intraoperative application of a combination of fat graft and platelet-rich fibrin appears to be effective on nerve healing after surgery at both the early and late periods.

2.
Braz. dent. sci ; 26(1): 1-10, 2023. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1412861

ABSTRACT

Objective: to evaluate the differentiation and gene expression of transcripts related to osteogenesis in a primary culture of Mesenchymal Stem Cells (MSCs) derived from rat femurs submitted to radiotherapy and the installation of pure titanium implants. Material and Methods: fifty-four rats received titanium implants in both femurs and were divided into three groups: Control: implant surgery (C); Implant + immediate irradiation (IrI), and Implant + late irradiation (IrL). Euthanasia occurred 3, 14, and 49 days after surgery. The bone marrow MSCs from the femurs were isolated and cultivated. The cell viability, total protein content, alkaline phosphatase (ALP) activity, and the formation of mineralization nodules and cellular genotoxicity were analyzed. The gene expression of Alkaline Phosphatase (phoA), Collagen 1 (COL1), Runt-related transcription factor 2 (RUNX2), Osterix (OSX), Osteopontin (OPN), Integrin ß1(ITGB1), Bone Sialoprotein (BSP), Osteonectin (SPARC), Osteocalcin (Bglap), Transforming Growth Factor ß-type (TGF-ß), Granulocyte Macrophage Colony Stimulating Factor (GM-CSF), Interleukin-6 (IL-6), Apolipoprotein E (APOE) and Prostaglandin E2 synthase (PGE2) were evaluated by qRT- PCR. Results: ionizing radiation suppresses the gene expression of essential transcripts for bone regeneration, as well as cellular viability, as observed in the IrI and IrL groups. Conclusion: although this can lead to the loss of osseointegration and failure of the implant, the MSCs showed more activity at 49 days than at 3 and 14 days. (AU)


Objetivo: avaliar a diferenciação e expressão gênica de transcritos relacionados à osteogênese em cultura primária de MSCs derivadas de fêmures de ratos submetidos à radioterapia e instalação de implantes de titânio puro. Material e Métodos: cinquenta e quatro ratos receberam implantes de titânio em ambos os fêmures e foram divididos em três grupos: Controle: cirurgia de implante (C); Implante + irradiação imediata (IrI) e Implante + irradiação tardia (IrL). A eutanásia ocorreu 3, 14 e 49 dias após a cirurgia. As MSCs de medula óssea dos fêmures foram isoladas e cultivadas. Foram analisadas a viabilidade celular, teor de proteína total, atividade da fosfatase alcalina (ALP), formação de nódulos de mineralização e genotoxicidade celular. A expressão gênica de Fosfatase Alcalina (phoA), Colágeno 1 (COL1), fator de transcrição relacionado a Runt 2 (RUNX2), Osterix (OSX), Osteopontina (OPN), Integrina ß1 (ITGB1), Sialoproteína Óssea (BSP), Osteonectina (SPARC), Osteocalcina (Bglap), Fator de Crescimento Transformador tipo ß (TGF-ß), Fator Estimulante de Colônia de Granulócitos-Macrófagos (GM-CSF), Interleucina-6 (IL-6), Apolipoproteína E (APOE) e Prostaglandina E2 sintase (PGE2) foram avaliados por qRT-PCR. Resultados: a radiação ionizante suprime a expressão gênica de transcritos essenciais para a regeneração óssea, bem como a viabilidade celular, como observado nos grupos IrI e IrL. Conclusão:embora isso possa levar à perda da osseointegração e falha do implante, as MSCs apresentaram maior atividade aos 49 dias do que aos 3 e 14 dias (AU)


Subject(s)
Animals , Rats , Osteogenesis , Bone Regeneration , Dental Implants , Clinical Protocols , Osseointegration , Neoplasms
3.
Biosci. j. (Online) ; 39: e39022, 2023.
Article in English | LILACS-Express | LILACS | ID: biblio-1425132

ABSTRACT

Resistance to acetolactate synthase (ALS) inhibitors have increased recently in South Brazil where the major weeds of flooded rice (barnyardgrass and weedy rice) have evolved resistance to imazapyr+imazapic. The aim of this research was to evaluate a growth medium for tissue regeneration of tillers in barnyardgrass, as well as an agar-based bioassays test (also from tillers) to detect susceptible and resistant biotypes of weedy rice and barnyardgrass to imazapyr+imazapic in vitro. Greenhouse experiments were conducted to detect ALS-resistant (R) and susceptible (S) weedy rice and barnyardgrass biotypes, and bioassays were carried out to evaluate an adequate growth medium for barnyardgrass tiller regeneration and determine the concentration of herbicide to distinguish R and S plants. The culture medium that provided a suitable barnyardgrass growth was MS 50% with the addition of benzylamino-purine. The tissue regeneration in vitro with the growth medium containing imazapyr+imazapic allowed to discriminate between R and S barnyardgrass and weedy rice plants. The concentration required for satisfactory control of susceptible barnyardgrass and weedy rice explants grown in vitro was 0.9 µM and 1.3 µM of imazapyr+imazapic herbicide, respectively. The bioassay in vitro using tiller regeneration provides an opportunity to predict effectively imazapyr+imazapic resistance in barnyardgrass and weedy rice.

4.
Braz. j. biol ; 83: e244732, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1278538

ABSTRACT

Abstract Some studies report the positive effect of organic residues from ant nests on soil properties and on the structure of the adjacent plant community in field experiments, but there is a gap about the effect on individual species. The purpose of the present study was to compare the soil nutrient content and the development of Turnera subulata Smith, an ornamental species, in the presence of the nest refuse (basically composed of fragments of grass leaves and the symbiotic fungus) produced by the leaf-cutting ant Acromyrmex balzani (Emery, 1890) or in control soil through a greenhouse pot experiment. The experiment was carried out with two treatments: control soil and soil with 25% of nest refuse. The plants were kept in 1L pots for 90 days. We evaluated the parameters: plant height, stem diameter, root length, number of leaves, dry weight of the root, dry and fresh aboveground biomass. Additionally, the relative chlorophyll content and leaf nutrients were used as nutritional parameters. As a result, plants that grew in the soil with nest refuse showed significant higher values of all parameters evaluated when compared to the control treatment (p < 0.001). We conclude that this biofertilizer contributed to the production of more vigorous plants, being able to act on the local dynamics of nutrients in the ecosystems where A. balzani occurs. As it is relatively abundant and easy to collect, the refuse of A. balzani has the potential to be used as an alternative substrate in the production of shortlife cycle plants.


Resumo Alguns estudos relatam o efeito positivo de resíduos orgânicos de formigueiros nas propriedades do solo e na estrutura da comunidade de plantas adjacentes em experimentos de campo, mas há uma lacuna sobre o efeito em espécies individuais. O objetivo do presente estudo foi comparar o desenvolvimento de Turnera subulata Smith, uma espécie ornamental, na presença do substrato de descarte (SD) de formigueiros produzido pela formiga cortadeira Acromyrmex balzani (Emery, 1890) por meio de experimento em casa de vegetação. O experimento foi conduzido com dois tratamentos: solo controle e solo com 25% de SD. As plantas foram mantidas em vasos de 1L por 90 dias. Foram avaliados os parâmetros: altura da planta, diâmetro do caule, comprimento da raiz, número de folhas, massa seca da raiz, biomassa seca e fresca da parte aérea. Além disso, o conteúdo relativo de clorofila e os nutrientes foliares foram usados como parâmetros fisiológicos. Como resultado, as plantas que cresceram no solo com SD apresentaram valores significativamente maiores de todos os parâmetros avaliados quando comparadas ao tratamento controle (p < 0.001). Concluímos que esse biofertilizante contribuiu para a produção de plantas mais vigorosas, podendo atuar na dinâmica local de nutrientes nos ecossistemas onde A. balzani ocorre. Além disso, por ser relativamente abundante e fácil de coletar, o SD de A. balzani tem potencial para ser utilizado como biofertilizante na produção de plantas de ciclo de vida curta.


Subject(s)
Animals , Ants , Turnera , Plants , Soil , Symbiosis , Ecosystem , Plant Leaves
5.
Acta cir. bras ; 38: e380623, 2023. tab, graf
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1419861

ABSTRACT

ABSTRACT Purpose: To evaluate the in vivo efficiency of commercial polymeric membranes for guided bone regeneration. Methods: Rat calvarial critical size defects was treated with LuminaCoat (LC), Surgitime PTFE (SP), GenDerm (GD), Pratix (PR), Techgraft (TG) or control (C-) and histomorphometric analysis determined the percentage of new bone, connective tissue and biomaterial at 1 or 3 months. Statistical analysis used ANOVA with Tukey's post-test for means at same experimental time and the paired Student's t test between the two periods, considering p < 0.05. Results: New bone at 1 month was higher for SP, TG and C-, at 3 months there were no differences, and between 1 and 3 months PR had greater increase growthing. Connective tissue at 1 month was higher for C-, at 3 months for PR, TG and C-, and between 1 and 3 months C- had sharp decline. Biomaterial at 1 month was higher for LC, in 3 months for SP and TG, and between 1 and 3 months, LC, GD and TG had more decreasing mean. Conclusions: SP had greater osteopromotive capacity and limitation of connective ingrowth, but did not exhibit degradation. PR and TG had favorable osteopromotion, LC less connective tissue and GD more accelerated biodegradation.

6.
STOMATOLOGY ; (12): 88-91, 2023.
Article in Chinese | WPRIM | ID: wpr-965347

ABSTRACT

@#Chondroitin sulfate is an important component of extracellular matrix (ECM) in animal and human body. In recent years, chondroitin sulfate has been proven to have potential efficacy in biomedical application and has been widely used in bone regeneration and osteogenesis, especially in craniofacial reconstruction and dental medicine. Research shows that chondroitin sulfate derivatives and chondroitin sulfate composite scaffolds have great potential in promoting osteogenesis and biomineralization. However, due to the variety of chondroitin sulfate and various application forms, study on its mechanism of osteogenic repair is still insufficient. In this paper, biological characteristics, bone regeneration and osteogenesis of chondroitin sulfate, its application in different biomaterial design and future prospect are discussed.

7.
STOMATOLOGY ; (12): 11-17, 2023.
Article in Chinese | WPRIM | ID: wpr-965109

ABSTRACT

@#With the development of dental implant techniques, dental rehabilitation of partially or totally edentulous patients with oral implants has become a common practice. Adequate bone volume in the implant area is a key factor for the success of implant restoration. However, insufficient bone volume in the implant area is very common in clinical practice, which jeopardizes the structural, functional, and esthetic outcomes of implant treatment. Bone augmentation with bone grafts is one of the methods commonly used in clinical practice to meet the requirements of implantation. Properties of bone grafts, such as biocompatibility,osteoconduction, osteoinduction and osteogenesis, are important to the success of bone augmentation. This paper reviews current research on dental bone grafts about their clinically relevant capabilities, classification and their potential development in the future, in order to provide theoretical reference for clinical application of bone grafts and successful implant restoration.

8.
International Eye Science ; (12): 369-374, 2023.
Article in Chinese | WPRIM | ID: wpr-964231

ABSTRACT

AIM: To investigate the expression changes of MMP-12 during the long-term axon regeneration induced by the lens injury after the optic nerve clamp trauma in sprague-dawley(SD)rats.METHODS: The optic nerve injury model and lens injury model of SD rats were established, and the 24 experimental animals were divided into control group; lens injury group; optic nerve injury group; lens injury combined with optic nerve injury group, with 6 rats in each group. Reference transcriptome sequencing was used to analyze the expression changes of differentially expressed genes in the injured optic nerve region, and relevant differentially expressed genes with high expression were screened. Quantitative real-time polymerase chain reaction(qRT-PCR)and enzyme-linked immunosorbent assay(ELISA)were used to quantify the expression changes of matrix metalloproteinase-12(MMP-12)in the injured optic nerve region.RESULTS: The Principal Component Analysis of transcriptome sequencing indicated that lens injury combined with optic nerve injury was the principal component of gene expression change. Analysis of gene expression differences showed that the expression of MMP-12 gene was up-regulated in the lens injury combined with optic nerve injury group. The mRNA expression level of MMP-12 in the lens injury combined optic nerve injury group was up-regulated compared with the control group, the optic nerve injury group and the lens injury group at 14d and 21d after successful modeling(P<0.05). At 7, 28d, there was no difference in expression among all groups. The protein expression level of MMP-12 in the lens injury combined with optic nerve injury group was up-regulated compared with the control group and optic nerve injury group at 7, 14 and 21d after successful modeling(P<0.05), and it was up-regulated in the lens injury group combined with optic nerve injury group compared with optic nerve injury group at 21d(P<0.05). At 28d, there was no difference in expression among all groups.CONCLUSION: The up-regulated expression of MMP-12 may be involved in the long-term regeneration of the optic nerve after lens injury.

9.
Article in Chinese | WPRIM | ID: wpr-961335

ABSTRACT

Objective@# To analyze the current status, hotspots, and trends in the field of stem cell therapies for periodontal tissue engineering based on bibliometric analysis.@*Methods @# The literature on stem cell therapies for periodontal tissue engineering in animal experiments and clinical studies was searched in the Web of Science core database up to December 31, 2021. The bibliometric analysis of the relevant literature data was carried out by using the "Bibliometrix" package of R language.@*Results @#A total of 304 articles were included, and the number of publications and the citation frequency are increasing. The number of related studies from China ranks first in the world with 166 publications; the institution with the largest number of publications is the Fourth Military Medical University; the author with the largest number of publications is Jin Y; and Tissue Engineering Part A had the most related publications. The hotspots of stem cell therapies for periodontal tissue engineering are mainly focused on tissue engineering and periodontal ligament regeneration, while the frontiers are mainly focused on exosomes, gold nanoparticles, and angiogenesis. @*Conclusion@#Research on stem cell therapies for periodontal tissue engineering continues to expand, and the academic influence is gradually increasing. Future research directions should focus on periodontal ligament regeneration, exosomes, gold nanoparticles and angiogenesis.

10.
Article in Chinese | WPRIM | ID: wpr-961109

ABSTRACT

@#Basic research on pulp regeneration requires in vivo experiments. The PubMed database was searched for in vivo models of stem cell-based pulp regeneration using the following keywords: "pulp regeneration", "stem cell" and "animal model". The retrieved models were classified into ectopic, semiorthotopic and orthotopic regeneration models and their characteristics and clinical values were reviewed. This literature review indicated that the ectopic regeneration model is the most widely used model for the simple steps. However, this model does not accurately capture clinical situations. The semiorthotopic regeneration model, which is an improvement of the ectopic regeneration model, can create a more realistic regeneration environment. The orthotopic regeneration model can simulate clinical procedures that more closely resemble application, but it is less commonly used for difficult operations and long experimental periods. The applicability of the above three animal models depend on the stage of the animal experiment: the ectopic regeneration model is suitable to test the regenerative effect and biocompatibility of the implant complex; the semiorthotopic regeneration model is suitable to more persuasively evaluate the regeneration effect of the implant complex; and the orthotopic regeneration model is suitable to confirm the regeneration effect and practicability of the regenerative implant complex prior to clinical study.

11.
Article in Chinese | WPRIM | ID: wpr-960873

ABSTRACT

@#Ideal sutures can provide great fixation, wound closure and a stable environment for healing of the surgical site. Tension-free apposition sutures are important for tissue regeneration and could tackle insufficient amounts of soft and hard tissue, especially in missing tooth sites that require implantation. The internal horizontal mattress suture, similar to the conventional horizontal mattress suture, forms a rectangle that can be bisected by the incision with both intrusion and extrusion of the needle on each side. On the basis of the rectangle, the internal horizontal mattress suture emphasizes that the suture should be located below the incision, so the eversion of the wound margin is the highlight of this procedure. The internal horizontal mattress suture could stabilize the graft on the targeting tissue, realize the fixation of the collagen membrane, apically repositioned flap and soft tissue graft, reduce the tension on the incision, and further release the tension of the incision margin. Beyond the primary need for fixation and wound closure, internal horizontal mattress sutures can also achieve stress interruption that reduces the interference of the surrounding muscle and can better master wound tension with the assistance of interrupted sutures. Given the above advantages, horizontal internal mattress sutures have great potential in the application of implant-related regenerative surgery. In this review, according to our experience in clinical practice and the literature, we summarize the advantages of internal horizontal mattress sutures in tissue augmentation. In addition, the sites and sequence to insert the needle and the spatial relationship between the suture and incision are clarified with the rationale of the naming pattern, which is conducive to experience exchange and clinical practice.

12.
Arq. ciências saúde UNIPAR ; 27(3): 1493-1511, 2023.
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1426466

ABSTRACT

Os cistos residuais são definidos como cistos inflamatórios, revestidos por epitélio e em seu interior apresentam um conteúdo semifluido ou fluido, que em sua dominância ocorrem na maxila. Em geral não apresentam sintomas e se não tratado corretamente pode ocasionar uma reabsorção óssea e enfraquecimento da maxila ou mandíbula. O principal objetivo deste trabalho é relatar o caso de uma paciente do sexo feminino, que compareceu a Clinica Odontológica relatando um cisto na região dos incisivos centrais superiores. No exame clinico, notou-se um aumento de volume na porção vestibular do processo alveolar, sendo sua consistência macia e sintomatologia dolorosa a palpação. Portanto, optou-se por sua enucleação cirúrgica da lesão, seguida de uma minuciosa descontaminação mecanica e quimica, seguida de regeneração óssea guiada utilizando um enxerto ósseo sintético a base de fosfato de cálcio e hidroxiapatia sendo seu diagnóstico confirmado através de exame histopatológico. Contudo neste relato pode-se observar que a enucleação do cisto residual seguida por uma boa descontaminação mecanica e quimica, associado a regeneração óssea guiada se mostrou eficaz no tratamento deste caso, não ocorrendo recidivas no periodo de acompanhamento. PALAVRAS-CHAVE: Cistos Residuais; Cistos Odontogênicos; Biópsia; Regeneração Óssea Guiada; Enxerto Ósseo.


Residual cysts are defined as inflammatory cysts, covered by epithelium and in their interior they have a semi-fluid or fluid content, which in their dominance occur in the maxilla. In general, they do not have symptoms and if not treated correctly, it can cause bone resorption and weakening of the maxilla or mandible. The main objective of this work is to report the case of a female patient, who attended the Dental Clinic reporting a cyst in the region of the upper central incisors. On clinical examination, an increase in volume was noted in the vestibular portion of the alveolar process, with a soft consistency and painful symptoms on palpation. Therefore, we opted for its surgical enucleation of the lesion, followed by a thorough mechanical and chemical decontamination, followed by guided bone regeneration using a synthetic bone graft based on calcium phosphate and hydroxyapathy, the diagnosis being confirmed through histopathological examination. However, in this report, it can be seen that the enucleation of the residual cyst followed by good mechanical and chemical decontamination, associated with guided bone regeneration, proved to be effective in the treatment of this case, with no recurrences occurring during the follow-up period.


Los quistes residuales se definen como quistes inflamatorios, recubiertos por epitelio y en su interior tienen un contenido semilíquido o líquido, que en su predominio se presentan en el maxilar. Por lo general, no presentan síntomas y si no se tratan correctamente, pueden causar reabsorción ósea y debilitamiento del maxilar o la mandíbula. El objetivo principal de este trabajo es reportar el caso de una paciente de sexo femenino, que acudió a la Clínica Odontológica por presentar un quiste en la región de los incisivos centrales superiores. Al examen clínico se aprecia aumento de volumen en la porción vestibular del proceso alveolar, de consistencia blanda y sintomatología dolorosa a la palpación. Por ello, se optó por su enucleación quirúrgica de la lesión, seguida de una exhaustiva descontaminación mecánica y química, seguida de regeneración ósea guiada mediante injerto óseo sintético a base de fosfato cálcico e hidroxiapatía, confirmándose el diagnóstico mediante examen histopatológico. Sin embargo, en este reporte se puede ver que la enucleación del quiste residual seguida de una buena descontaminación mecánica y química, asociada a la regeneración ósea guiada, demostró ser eficaz en el tratamiento de este caso, sin que se presentaran recurrencias durante el seguimiento período de subida.

13.
Braz. j. otorhinolaryngol. (Impr.) ; 89(1): 79-89, Jan.-Feb. 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1420933

ABSTRACT

Abstract Objectives: The benefit of corticosteroids following facial nerve neurorrhaphy in the setting of complete transection is questionable. This systematic review and meta-analysis aimed to evaluate corticosteroid efficacy on facial nerve regeneration and functional recovery after complete disruption and neurorrhaphy. Methods: Randomized controlled trials on both human and animal models from Ovid MEDLINE and Ovid EMBASE studying corticosteroid efficacy in complete facial nerve disruption followed by neurorrhaphy were included. Data were extracted and pooled for meta-analysis. The outcomes were evaluated from electrophysiology, histology, and functional recovery. However, no randomized controlled trial in human was performed. Possibly, performing human trials with histopathology may not be feasible in clinical setting. Results: Six animal studies (248 participants) met inclusion criteria. Electrophysiologic outcomes revealed no differences in latency (Standardized Mean Difference (SMD) = −1.97, 95% CI −7.38 to 3.44, p = 0.47) and amplitude (SMD = 0.37, 95% CI −0.44 to 1.18, p = 0.37) between systemic corticosteroids and controls. When analysis compared topical corticosteroid and control, the results provided no differences in latency (Mean Difference (MD)=0.10, 95% CI −0.04 to 0.24, p = 0.16) and amplitude (SMD = 0.01, 95% CI −0.08 to 0.10, p = 0.81). In histologic outcomes, the results showed no differences in axon diameter (MD = 0.13, 95% CI −0.15 to 0.41, p = 0.37) between systemic corticosteroid and control; however, the result in myelin thickness (MD = 0.06, 95% CI 0.04 to 0.08, p < 0.05) favored control group. When comparing systemic corticosteroid with control in eye blinking, the results favored control (MD= 1.33, 95% CI 0.60 to 2.06, p = 0.0004). Conclusions: This evidence did not show potential benefits of systemic or topical corticosteroid deliveries after facial nerve neurorrhaphy in complete transection when evaluating electrophysiologic, histologic, and functional recovery outcomes in animal models.

14.
Biol. Res ; 562023.
Article in English | LILACS-Express | LILACS | ID: biblio-1429915

ABSTRACT

Background Splenectomy may lead to severe postoperative complications, including sepsis and cancers. A possible solution to this problem is heterotopic autotransplantation of the spleen. Splenic autografts rapidly restore the regular splenic microanatomy in model animals. However, the functional competence of such regenerated autografts in terms of lympho- and hematopoietic capacity remains uncertain. Therefore, this study aimed to monitor the dynamics of B and T lymphocyte populations, the monocyte-macrophage system, and megakaryocytopoiesis in murine splenic autografts. Methods The model of subcutaneous splenic engraftment was implemented in C57Bl male mice. Cell sources of functional recovery were studied using heterotopic transplantations from B10-GFP donors to C57Bl recipients. The cellular composition dynamics were studied by immunohistochemistry and flow cytometry. Expression of regulatory genes at mRNA and protein levels was assessed by real-time PCR and Western blot, respectively. Results Characteristic splenic architecture is restored within 30 days post-transplantation, consistent with other studies. The monocyte-macrophage system, megakaryocytes, and B lymphocytes show the highest rates, whereas the functional recovery of T cells takes longer. Cross-strain splenic engraftments using B10-GFP donors indicate the recipient-derived cell sources of the recovery. Transplantations of scaffolds populated with splenic stromal cells or without them afforded no restoration of the characteristic splenic architecture. Conclusions Allogeneic subcutaneous transplantation of splenic fragments in a mouse model leads to their structural recovery within 30 days, with full reconstitution of the monocyte-macrophage, megakaryocyte and B lymphocyte populations. The circulating hematopoietic cells provide the likely source for the cell composition recovery.

15.
J. appl. oral sci ; 31: e20220427, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1430628

ABSTRACT

Abstract Objective To investigate the angiogenesis in human umbilical vein endothelial cells (HUVEC) under high glucose concentration, treated with exosomes derived from stem cells from human exfoliated deciduous teeth (SHED). Methodology SHED-derived exosomes were isolated by differential centrifugation and were characterized by nanoparticle tracking analysis, transmission electron microscopy, and flow cytometric assays. We conducted in vitro experiments to examine the angiogenesis in HUVEC under high glucose concentration. Cell Counting Kit-8, migration assay, tube formation assay, quantitative real-time PCR, and immunostaining were performed to study the role of SHED-derived exosomes in cell proliferation, migration, and angiogenic activities. Results The characterization confirmed SHED-derived exosomes: size ranged from 60-150 nm with a mode of 134 nm, cup-shaped morphology, and stained positively for CD9, CD63, and CD81. SHED-exosome significantly enhanced the proliferation and migration of high glucose-treated HUVEC. A significant reduction was observed in tube formation and a weak CD31 staining compared to the untreated-hyperglycemic-induced group. Interestingly, exosome treatment improved tube formation qualitatively and demonstrated a significant increase in tube formation in the covered area, total branching points, total tube length, and total loop parameters. Moreover, SHED-exosome upregulates angiogenesis-related factors, including the GATA2 gene and CD31 protein. Conclusions Our data suggest that the use of SHED-derived exosomes potentially increases angiogenesis in HUVEC under hyperglycemic conditions, which includes increased cell proliferation, migration, tubular structures formation, GATA2 gene, and CD31 protein expression. SHED-exosome usage may provide a new treatment strategy for periodontal patients with diabetes mellitus.

16.
Rev. Univ. Ind. Santander, Salud ; 54: e801, Dec. 2022. graf
Article in Spanish | LILACS | ID: biblio-1407045

ABSTRACT

Resumen Debido a los diferentes problemas existentes a la hora de realizar procedimientos implantológicos por la calidad del remanente óseo y el estado de los tejidos periodontales en la zona a rehabilitar, existen opciones de regeneración ósea inducida que muestran tasas de éxito considerablemente favorables al ser empleadas en casos donde es necesario una regeneración ósea extensa capaz de soportar un implante dental. El objetivo del presente estudio es describir el éxito en la regeneración ósea por medio de alternativas combinadas de fibrina rica en plaquetas y modificación biológica con tetraciclina. Reporte del caso clínico: paciente femenina de 67 años que consulta por inflamación, supuración y dolor en la zona antero-superior. Es diagnosticada como absceso periapical crónico, se hace cirugía de extracción de órganos dentales, posterior a eso se hace descontaminación y adaptación de los alveolos con tetraciclina para realizar la regeneración ósea guiada con fibrina rica en plaquetas, hueso tipo Lumina Bone Porous y Lumina Coat, luego se espera el proceso de evolución para colocación de implantes dentales. El éxito obtenido con el uso de fibrina rica en plaquetas y la biomodificacion ósea como coadyuvante en la desinfección de la zona a tratar, logró mostrar resultados altamente favorables en el proceso de regeneración ósea guiada.


Abstract As the different problems that exist when carrying out implant procedures due to the quality of the bone remnant and the state of the existing periodontal tissues in the area to be rehabilitated, there are induced bone regeneration options that show considerably favorable success rates as they are used in cases where extensive bone regeneration is necessary to support a dental implant. The objective of the present study is to describe the success in bone regeneration using combined alternatives of platelet-rich fibrin and biological modification with tetracycline. Report of the clinical case: 67-year-old female patient consulted for inflammation and suppuration and pain in the upper antero-superior area, she was diagnosed as chronic periapical abscess, dental organ extraction surgery was performed, after that decontamination and adaptation of the alveoli was performed with tetracycline to perform guided bone regeneration with platelet-rich fibrin, Coat membrane and Lumina bone criteria, then wait for the evolution process to place dental implants. The success obtained with the use of FRP and bone biomodification as an adjuvant in the disinfection of the area to be treated achieved to show highly favorable results in the guided bone regeneration process.


Subject(s)
Humans , Female , Aged , Platelet-Rich Fibrin , Periapical Abscess , Biological Products , Bone Regeneration , Dental Implants , Antisepsis
17.
Medicentro (Villa Clara) ; 26(4): 985-994, oct.-dic. 2022. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1405687

ABSTRACT

RESUMEN La técnica de preservación de papilas en el tratamiento de las periodontitis ofrece ventajas en cuanto a la protección del sitio del defecto cuando en este se pretende realizar cirugía ósea aditiva. La combinación de este proceder con la regeneración tisular guiada garantiza mayor protección a la membrana colocada con este fin. Se presenta el caso de un paciente de 47 años de edad, masculino, cibernético de profesión, que recibió tratamiento periodontal pero no acudió a su fase de mantenimiento y en este momento lo hace por presentar movilidad y sangrado gingival manifestado fundamentalmente al realizar los procedimientos de higiene bucal. Se le realizó un colgajo con preservación de papilas, entre los incisivos centrales superiores, colocándole un injerto de Bio-Oss y una membrana de colágeno, con lo que se obtuvo una mayor altura del hueso y una disminución de la profundidad de la bolsa.


ABSTRACT The papillae preservation technique in the treatment of periodontitis offers advantages in terms of protecting the defect site when additive bone surgery is intended to be performed on it. The combination of this procedure with guided tissue regeneration guarantees greater protection for the membrane placed for this purpose. We present a 47-year-old male patient, computer engineer as a profession, who received periodontal treatment but did not attend his maintenance phase; he does so due to mobility and gingival bleeding manifested mainly when performing oral hygiene procedures. A papilla-preserving flap was made between the upper central incisors, placing a Bio-Oss graft and a collagen membrane, which resulted in greater bone height and decreased pocket depth.

18.
Rev. chil. neuro-psiquiatr ; 60(4): 465-472, dic. 2022.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1423709

ABSTRACT

Los mecanismos moleculares fisiológicos asociados a la respuesta ante el estrés agudo y crónico permiten entender los cambios que éstos pueden producir en los diversos tejidos del cuerpo. Diversas investigaciones resaltan el papel del estrés crónico en el desarrollo de disfunciones que afectan el equilibrio corporal; sin embargo, hay que considerar que los mecanismos relacionados con el estrés agudo, también pueden influir en el desarrollo de patologías y de la progresión de las manifestaciones deletéreas del estrés crónico. Por otro lado, uno de los tejidos más estudiados en los últimos años ha sido el tejido óseo, ya que éste se encuentra influenciado por factores nerviosos, endocrinos e inmunológicos. Esta revisión busca analizar las bases neurocientíficas de los mecanismos moleculares del estrés y su relación en el proceso de reparación ósea. Para esto, se realizó una búsqueda de la literatura en las bases de datos de Pubmed, Scopus y ScienceDirect, concluyendo que el estrés modifica la liberación de neurotransmisores, la acción del sistema nervioso autónomo, la liberación de hormonas corticotrópicas y la actividad de diversas citocinas; lo que conlleva al desequilibrio de los procesos de regulación y reparación del tejido óseo sometido a carga o lesión.


The physiological molecular mechanisms associated with the response to acute and chronic stress allow us to understand the changes that these can produce in the various tissues of the body. Various investigations highlight the role of chronic stress in the development of dysfunctions that affect body balance; However, it must be considered that the mechanisms related to acute stress can also influence the development of pathologies and the progression of the deleterious manifestations of chronic stress. On the other hand, one of the most studied tissues in recent years has been bone tissue, since it is influenced by nervous, endocrine and immunological factors. This paper seeks to analyze the neuroscientific bases of the molecular mechanisms of stress and their relationship in the bone repair process. Therefore, a literature search was carried out in the Pubmed, Scopus and ScienceDirect databases. Concluding that stress modifies the release of neurotransmitters, the action of the autonomic nervous system, the release of corticotropic hormones and the activity of various cytokines; which leads to the imbalance of the regulation and repair processes of the bone tissue subjected to load or injury.


Subject(s)
Humans , Bone and Bones , Bone Regeneration , Neurosciences , Stress Disorders, Traumatic, Acute
19.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1421723

ABSTRACT

Introducción: La corticotomía corresponde a un procedimiento quirúrgico, basado en el Fenómeno de Aceleración Regional (RAP), que tiene por objetivo disminuir hasta en un tercio el tiempo del tratamiento ortodóncico. Esta técnica se puede ejecutar agregando un injerto óseo que aumenta el grosor alveolar, lo que se conoce como Ortodoncia Osteogénica Acelerada Periodontalmente (PAOO) permitiendo un movimiento más amplio y rápido. Objetivo: Determinar la condición final del tejido óseo vestibular en pacientes tratados con corticotomía que recibieron injerto óseo versus pacientes que no recibieron. Materiales y métodos: Se realiza una búsqueda electrónica en la Biblioteca Nacional de Medicina PUBMED bajo la estrategia: "orthodontics" OR "orthodontic treatment" and "osteotomy" OR "corticotomy" OR "periodontally accelerated" and "bone graft" OR "bone grafting" OR "augmented corticotomy" AND "tooth movement". Se realizó el análisis de riesgo de sesgo con la herramienta ROBINS-I. Resultados: La búsqueda arrojo un total de 92 artículos de los cuales 4 fueron elegidos para el análisis Conclusión: Existe una cantidad limitada de estudios sobre el tema, presentando riesgo de sesgo de moderado a alto. Considerando esto, la evidencia indica que la utilización de injerto óseo y membrana contribuye a mejorar las condiciones anatómicas, especialmente si esta última se utiliza fijada.


Introduction: Corticotomy is a surgical procedure based on the Regional Acceleratory Phenomenon (RAP), whose objective is to reduce up to a third the time of orthodontic treatment. This technique can be performed adding a bone graft for the augmentation of the alveolar width and allowing a broader movement. This is known as Periodontally accelerated osteogenic orthodontics (PAOO). Objective: To determine the final condition of the buccal bone tissue after treatment in patients who received corticotomy and bone graft versus corticotomy alone. Materials and methods: An electronic search in the National Library of Medicine PUBMED was performed utilizing the following strategy: "orthodontics" OR "orthodontic treatment" and "osteotomy" OR "corticotomy" OR "periodontally accelerated" and "bone graft" OR "bone grafting" OR "augmented corticotomy" AND "tooth movement". Risk of bias analysis was done utilizing the ROBINS-I tool. Results: The search yielded a total of 92 articles, of which 4 were considered for analysis. Conclusion: There is a limited number of studies regarding this topic and their risk of bias is moderate to high. Thus, the available evidence suggests that the use of bone graft and a resorbable membrane contributes to the improvement of the anatomical conditions, especially if the latter is fixed.

20.
Rev. Ciênc. Méd. Biol. (Impr.) ; 21(2): 292-301, out.2022. fig, tab
Article in Portuguese | LILACS | ID: biblio-1400243

ABSTRACT

A dentina e o osso alveolar apresentam muita semelhança em sua composição. Sendo assim, podemos considerar a utilização da dentina como recurso alternativo nas intervenções que buscam a regeneração tecidual óssea. Objetivo: o presente estudo realizou uma revisão integrativa da literatura sobre o uso da dentina como biomaterial para regeneração óssea. Metodologia: foi realizada uma busca por artigos, nas bases de dados Medline, via PubMed; Scielo, LILACS, BASE, Scopus e Science Direct, queavaliassem ou descrevessem o uso da dentina como biomaterial para regeneração óssea. Foram utilizados os seguintes descritores: "Dentin" AND "Bone Regeneration", sem delimitação de tempo. Os critérios de inclusão foram: estudos clínicos publicados em periódicos, oriundos de dados primários, sobre o uso de dentina como biomaterial. Os critérios de exclusão foram: revisões de literatura, estudos in vitro e em animais, estudos que não fosse possível o acesso na íntegra e estudos que associassem o uso da dentina com outros biomateriais sem que fosse possível relacionar os resultados apenas pelo uso da dentina. Resultados: vinte e três estudos foram selecionados para a presente revisão. As pesquisas demonstraram que há uma heterogenicidade relacionada ao tamanho da partícula de dentina obtida, que pode ser decorrente de diferentes métodos de processamento. Conclusão: a reutilização da dentina como biomaterial pode ser uma alternativa promissora ao enxerto autógeno. Sugere-se, então, que protocolos de processamento da partícula de dentina sejam melhor estabelecidos e estudos longitudinais precisam ser realizados para a garantia de procedimentos seguros, eficazes e práticos.


The dentin and the alveolar bone are very similar in composition, therefore, it's usage as an alternative resource in interventions that seek tissue regeneration can be considered. Objective: the aim of the present study was to carry out an integrative review of the literature on the use of dentin as a biomaterial for bone regeneration. Methodology: a search for articles was carried out in the Medline databases, via PubMed; Scielo, LILACS, BASE, Scopus and Science Direct, which evaluated or described the use of dentin as a biomaterial for bone regeneration. The following descriptors were used: "Dentin" AND "Bone Regeneration", without time limits. The inclusion criteria were: clinical studies published in journals, derived from primary data, on the use of dentin as a biomaterial. Exclusion criteria were: literature reviews, in vitro and in animal studies, studies that were not possible to be accessed in full and studies that associated the usage of dentin with other biomaterials and that it was not possible to relate the results just by using the dentin. Results: twenty-three studies were selected for the present review. Researches have shown that there is heterogeneity related to the size of the obtained dentin particle, which may be due to different processing methods. Conclusion: the reuse of dentin as a biomaterial can be a promising alternative to autogenous graft. It is suggested, then, that dentin particle processing protocols should are better established and longitudinal studies need to be carried out to the in order to ensure safe, effective and practical procedures.


Subject(s)
Humans , Animals , Male , Female , Adult , Middle Aged , Transplantation, Autologous , Biocompatible Materials , Bone Regeneration , Dentin
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