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2.
J Oral Pathol Med ; 52(2): 169-180, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36258298

RESUMO

BACKGROUND AND OBJECTIVE: Leucocyte- and platelet-rich fibrin has been developed to stimulate wound healing response. However, it is currently unknown whether smoking affects the biological responses elicited by leucocyte- and platelet-rich fibrin on periodontal ligament-derived mesenchymal stromal cells. This study analyzes the kinetics of biomolecule release from leucocyte- and platelet-rich fibrin derived from smokers and nonsmokers and their effect on periodontal ligament cell proliferation and migration as essential biological activities during wound healing. METHODS: Biomolecules present in leucocyte- and platelet-rich fibrin exudates and conditioned media collected from smokers and nonsmokers were analyzed by Luminex arrays. Periodontal ligament-derived mesenchymal stromal cell obtained from one nonsmoker were treated with leucocyte- and platelet-rich fibrin exudates or leucocyte- and platelet-rich fibrin conditioned media derived from both smokers and nonsmokers. The parameters evaluated included cell proliferation, determined by Ki67 immunostaining and migration assessed using transwell assays. Also, cells were treated with nicotine in the presence of fetal bovine serum 10% or leucocyte- and platelet-rich fibrin conditioned media. RESULTS: A similar biomolecular profile was detected in leucocyte- and platelet-rich fibrin exudates and leucocyte- and platelet-rich fibrin conditioned media from smokers and nonsmokers, stimulating (periodontal ligament-derived mesenchymal stromal cell) proliferation, and migration to a comparable degree. Nicotine reduced cell proliferation and migration of periodontal cells; however, this effect was recovered in the presence of leucocyte- and platelet-rich fibrin conditioned media. CONCLUSION: Leucocyte- and platelet-rich fibrin derived from smokers could be an autologous source of biomolecules to stimulate cell biological activities involved in wound healing in smokers who have difficulties in ceasing this habit. Clinical trials are required to evaluate the impact of leucocyte- and platelet-rich fibrin on healing responses in smokers.


Assuntos
Fibrina Rica em Plaquetas , Humanos , Ligamento Periodontal , Meios de Cultivo Condicionados/farmacologia , Nicotina/farmacologia , Fumar
3.
Environ Monit Assess ; 194(9): 614, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35895142

RESUMO

Aquatic ecosystems are affected by different land uses that modify gradients of environmental conditions. These impacts act directly on the community structure, especially the most sensitive ones, such as aquatic insects. Thus, dragonflies have been used as good models to assess these changes, since their suborders Anisoptera and Zygoptera have different ecophysiological and behavioral requirements. This study aimed to evaluate the following hypotheses: (1) dragonfly species composition differs along the environmental gradients of streams; therefore, we expect a higher proportion of species of the suborder Anisoptera in environments with a higher degree of disturbance, since these environmental conditions select heliothermic species with exophytic oviposition; (2) the reduction of habitat integrity and canopy cover will lead to a lower richness of the Zygoptera suborder, due to the restrictions of its thermoregulation and oviposition behavior in relation to Anisoptera, since the higher light input would favor heliothermic and exophytic species; (3) alterations in habitat integrity create ecological thresholds and points of change in the abundance and frequency of Odonata species, generating gradients in the environmental integrity conditions. Specimens were collected from 24 streams (first to third order), in a gradient of land uses. Canopy cover and stream width were predictors of taxonomic richness and abundance of the suborders Anisoptera and Zygoptera, with greater coverage and smaller width, positively affecting Zygoptera and negatively Anisoptera. The turning points were determined by a habitat integrity index, where below 0.38 there is an increase in generalist taxa and a decline in sensitive taxa. On the other hand, above 0.79, there was a sensitive taxa increase in detriment of generalists. Four individual taxa indicators were selected, two of which associated with a negative response (Perithemis tenera and Acanthagrion aepiolum) and two with positive responses (Epipleoneura metallica and Zenithoptera lanei) for habitat integrity. Our results are important to guide management strategies, recovery, and protection policies for areas of permanent protection, aiming to conserving biodiversity and natural resources essential to life quality maintenance.


Assuntos
Odonatos , Animais , Biodiversidade , Dipterocarpaceae , Ecossistema , Monitoramento Ambiental , Odonatos/fisiologia , Rios
4.
J Intensive Care Med ; 37(6): 753-763, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34812664

RESUMO

Objective: The aim of this study was to develop evidence-based recommendations for the diagnosis and treatment of sepsis in children in low- and middle-income countries (LMICs), more specifically in Latin America. Design: A panel was formed consisting of 27 experts with experience in the treatment of pediatric sepsis and two methodologists working in Latin American countries. The experts were organized into 10 nominal groups, each coordinated by a member. Methods: A formal consensus was formed based on the modified Delphi method, combining the opinions of nominal groups of experts with the interpretation of available scientific evidence, in a systematic process of consolidating a body of recommendations. The systematic search was performed by a specialized librarian and included specific algorithms for the Cochrane Specialized Register, PubMed, Lilacs, and Scopus, as well as for OpenGrey databases for grey literature. The GRADEpro GDT guide was used to classify each of the selected articles. Special emphasis was placed on search engines that included original research conducted in LMICs. Studies in English, Spanish, and Portuguese were covered. Through virtual meetings held between February 2020 and February 2021, the entire group of experts reviewed the recommendations and suggestions. Result: At the end of the 12 months of work, the consensus provided 62 recommendations for the diagnosis and treatment of pediatric sepsis in LMICs. Overall, 60 were strong recommendations, although 56 of these had a low level of evidence. Conclusions: These are the first consensus recommendations for the diagnosis and management of pediatric sepsis focused on LMICs, more specifically in Latin American countries. The consensus shows that, in these regions, where the burden of pediatric sepsis is greater than in high-income countries, there is little high-level evidence. Despite the limitations, this consensus is an important step forward for the diagnosis and treatment of pediatric sepsis in Latin America.


Assuntos
Sepse , Criança , Consenso , Cuidados Críticos/métodos , Humanos , América Latina , Sepse/diagnóstico , Sepse/terapia
5.
Risk Anal ; 42(1): 69-84, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34374448

RESUMO

We propose a Pandemic Risk Perception Scale. Our scale comprises two constructs, Dread Risk and Personal Exposure, divided into five dimensions: Infection Risk, Emotional Health Risk, Health System Risk,Financial Risk, and Alimentary Risk. Using multidimensional item response theory, confirmatory factor analysis, and structural equation modeling on two samples of respondents, our results show that Alimentary Risk, Health System Risk, and Emotional Health Risk are the main dimensions of risk perception for the COVID-19 pandemic. Furthermore, Infection Risk has a minor impact on the pandemic's risk perception, suggesting the presence of different dynamics between personal and general risk perceptions for the COVID-19 pandemic.


Assuntos
COVID-19/epidemiologia , Emoções/fisiologia , Pandemias , Percepção , Medição de Risco/métodos , SARS-CoV-2 , Inquéritos e Questionários , COVID-19/psicologia , Humanos
6.
Ciênc. rural (Online) ; 52(6): e20201067, 2022. tab
Artigo em Inglês | VETINDEX | ID: biblio-1350578

RESUMO

Society evolution is commonly followed by changes; however, some of them bring negative implications for the community. One of these consequences refers to environmental degradation, which has agricultural activity as one of its influencing agents, which is essentially characterized by man's predatory actions. Accordingly, this research analyzed the environmental degradation in 167 pattern in the agricultural world. Therefore, the Agricultural Environmental Degradation Index (IDAA) was used as a proxy for agricultural environmental degradation and the factor analysis technique. Results indicated that the most degraded country was Russia, which belongs to the European continent; however, the other positions were occupied predominantly by Africa, followed by North America and Oceania. Issues such as rural poverty and primitive natural settings can leverage this phenomenon. The lowest rates of degradation were concentrated on Central America and Europe, where agricultural activity was most incipient. In this sense, a directly proportional relationship between environmental degradation and agricultural practice was reported considering that countries dependent on this phenomenon had the most worrying results. Thereby, there is an emerging need for public policies that integrate economic and environmental dimensions that reduce negative impacts in the regions most degraded.


A evolução da sociedade comumente vem acompanhado de mudanças, no entanto, algumas delas têm trazido implicações negativas para a comunidade. Uma dessas consequências, diz respeito a degradação ambiental que tem como um de seus agentes influenciadores a atividade agropecuária, protagonizada essencialmente por ações predatórias do homem. Nesse sentido, o objetivo desse trabalho é analisar o padrão de degradação ambiental agropecuário de 167 países do mundo. Para tanto, foi utilizada a metodologia do Índice de Degradação Ambiental Agropecuária (IDAA) como proxy para a degradação ambiental agropecuária e a técnica de análise fatorial. Pelos resultados, identificou-se que o país mais degradado é a Rússia, pertencente ao continente europeu. Entretanto, as demais posições dos países mais degradados, foram predominantemente africanos, seguido do continente da América do Norte e Oceania. Questões como pobreza rural e cenários naturais primitivos podem alavancar esse fenômeno. Os menores índices de degradação concentraram-se nos continentes da América Central e Europa, onde a atividade agropecuária é mais incipiente. Nesse contexto, averiguou-se uma relação diretamente proporcional entre degradação ambiental e prática agropecuária, tendo em vista que países dependentes desse fenômeno foram os detentores de resultados mais preocupantes. Com isso, é emergente a necessidade de políticas públicas que integrem as dimensões econômicas e ambientais que atenuem os impactos negativos nas regiões mais degradadas.


Assuntos
Desequilíbrio Ecológico/políticas , Conservação dos Recursos Naturais/legislação & jurisprudência , Indústria Agropecuária/economia
7.
Biomed Res Int ; 2021: 9996071, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307687

RESUMO

BACKGROUND: Platelet concentrates like leucocyte- and platelet-rich fibrin (L-PRF) have been widely evaluated in different oral surgical procedures to promote the healing process. However, liquid L-PRF products such as liquid fibrinogen have been poorly explored, especially in the biomimetic functionalization of dental implants. The aim of this in vitro study is to evaluate the interaction between 5 different dental implant surfaces and liquid fibrinogen. METHODS: Five commercially available dental implants with different surfaces (Osseospeed™, TiUnite™, SLActive®, Ossean®, and Plenum®) were immersed for 60 minutes in liquid fibrinogen obtained from healthy donors. After this period, the implants were removed and fixed for scanning electron microscopy (SEM). RESULTS: All dental implants were covered by a fibrin mesh. However, noticeable noncontact areas were observed for the Osseospeed™, TiUnite™, and SLActive® surfaces. On the other hand, Ossean® and Plenum® surfaces showed a dense and uniform layer of fibrin covering almost the entire implant surface. The Osseospeed™, TiUnite™, and SLActive® surfaces presented with lower blood cell numbers inside the fibrin mesh compared with the others. Moreover, at higher magnification, thicker fibrin fibers were observed in contact with Ossean® and Plenum® surfaces. The Plenum ®surface showed the thickest fibers which also inserted and interconnect to the microroughness. CONCLUSION: The initial contact between an implant surface and the fibrin network differs significantly among different implant brands. Further studies are necessary to explore the clinical impact of these observations in the osseointegration process of dental implants.


Assuntos
Fibrinogênio/metabolismo , Implantes Dentários , Fibrina/metabolismo , Humanos , Microscopia Eletrônica de Varredura , Projetos Piloto
8.
Neotrop Entomol ; 50(3): 388-397, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33792857

RESUMO

Phenotypic variation in both morphology and symmetry of individuals may appear due to environmental stress caused by land-use changes. Here, we evaluated fluctuating asymmetry (FA) and wing size variations of two orchid bee species, Euglossa ignita Smith, 1874 and Eulaema meriana (Olivier, 1789), comparing 11 wing traits. We sampled the individuals from legal reserves (LR), areas of permanent protection (APP), and oil palm plantations (PALM) in Eastern Amazonia. We calculated FA as the absolute difference between the wing measurements made in the right and left wings of specimens and both species' wing size. We corrected each FA measure for possible directional asymmetry bias by subtracting the mean value of the mean FA signed difference to each FA measure. We compared FA and the size of each wing trait of each species between land-use types using one-way ANOVAs. We found no effect of FA between land-use types, but we observed individuals of both species from PALM areas having larger wings than those from LR areas. Our results demonstrate that there seems to be a pressure exerted by land-use change associated with palm oil cultivation favoring individuals with larger wings, although both species had shown substantial permeability of oil palm.


Assuntos
Abelhas/anatomia & histologia , Asas de Animais , Animais , Brasil , Fenótipo
9.
Ecol Lett ; 24(5): 1089-1102, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33617134

RESUMO

Despite the important roles of assortative mating for understanding evolutionary processes, our knowledge on the variation in assortative mating across populations and breeding periods has been overshadowed by the greater attention given to general patterns. Obtaining data on mating pairs are difficult for most species; therefore, researchers often group data from different populations or breeding periods, which can increase positive biases in detecting and estimating assortative mating. We used a meta-analytic approach to investigate the biases caused by spatially or temporally pooling data and the assortative mating consistency across populations and breeding periods. We describe assortative mating patterns across and within animal taxa. We performed a systematic review to search studies reporting measures of size-assortative mating (SAM). Grouping data from multiple populations and seasons incurred positive biases. Overall, assortative mating moderately exhibited low repeatability in space and time, but it was inconsistent for most taxa. After excluding pooled measures, the average estimate for assortative mating was moderate and positive. Thus, our findings demonstrate that pooling data can produce misleading results. We also highlight the importance of further investigation of hypotheses that explain spatial and temporal variation in assortative mating, after its detection. Our study reinforces the significance of investigating mating patterns at various spatial and temporal scales before drawing broad conclusions.


Assuntos
Preferência de Acasalamento Animal , Animais , Viés , Evolução Biológica , Reprodução , Estações do Ano
10.
J Oral Biol Craniofac Res ; 10(4): 625-628, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983856

RESUMO

OBJECTIVE: Quantify the effect of the osseodensification Densah® protocol on the insertion torque, ISQ, and the removal torque of conical BioHorizons® implants. MATERIALS AND METHODS: An ex vivo model over fresh pig tibia bone was used. Test group (TG) included 50 osteotomies using Densah® osseodensification protocol, and the control group (CG), 50 osteotomies using BioHorizons®'s recommended procedure. Conical BioHorizons® implants (3.8 × 10.5 mm) were implanted, verifying the insertion torque with a manual torque meter. ISQ values were registered with Ostell® device. Finally, implants were removed with manual reverse torque registering the values. Results were analyzed and compared with the Mann-Whitney test and t-test. RESULTS: Median and interquartile range per group were as follows: insertion torque, CG: 26 (12) Ncm; TG: 42 (26) Ncm, removal torque, CG: 25 (20) Ncm; TG: 40 (28) Ncm, ISQ value, CG: 69.25 (5.5); TG: 71.5 (4). All variables were significantly higher (p ≤ 0.05) in the osseodensification group. CONCLUSIONS: The Osseodensification technique may improve primary stability in the clinical scenario on tapered implants. Further human RCTs are necessary to validate this.

11.
PLoS One ; 15(2): e0229459, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32101578

RESUMO

On the latest 60 years the degradation and fragmentation of native habitats have been modifying the landscape in the eastern Brazilian Amazon. The adaptive plasticity of an organism has been crucial for its long-term survival and success in these novel ecosystems. In this study, we investigated the response of four endangered species of large terrestrial mammals to the variations in the quality of their original habitats, in a context of high anthropogenic pressure. The distribution of the Myrmecophaga tridactyla (Giant anteater), Priodontes maximus (Giant armadillo), Tapirus terrestris (Lowland tapir) and Tayassu pecari (White-lipped peccary) in all sampled habitats suggests their tolerance to degradation. However, the survival ability of each species in the different habitats was not the same. Among the four species, T. pecari seems to be the one with the least ability to survive in more altered environments. The positive influence of the anthropogenically altered habitats on abundances of three of the four species studied, as observed at the regeneration areas, can be considered as a potential indication of the ecological trap phenomenon. This study reinforces the importance of the forest remnants for the survival of endangered mammal species, in regions of high anthropogenic pressure, as in the eastern Brazilian Amazon.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Meio Ambiente , Mamíferos/classificação , Animais , Brasil , Espécies em Perigo de Extinção , Florestas , Densidade Demográfica
12.
Clin Oral Investig ; 24(3): 1151-1160, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31292776

RESUMO

OBJECTIVES: The aim of this study was to describe the histological and clinical outcome of "dentin block" (a mixture of autologous particulate dentin, leukocyte- and platelet-rich fibrin (L-PRF), and liquid fibrinogen) in alveolar ridge preservation. MATERIAL AND METHODS: Ten extraction sockets were grafted with "dentin block," a mixture of particulate autologous dentin with chopped leukocyte-platelet-rich fibrin (L-PRF) membranes at a 1:1 ratio, and liquid fibrinogen as a binder. Two grafted sites were followed at 4 and 5 months, and 6 sites at 6 months. Biopsies were taken from the core of the grafted site for histologic and histo-morphometric analysis. RESULTS: All patients completed the study without any adverse event. The vertical and horizontal dimensions of the alveolar ridge were preserved or even increased after 4, 5, or 6 months and remained stable after 6 months of the implant placement. The histological examination revealed a median relative percentage of bone, dentin, and connective tissue of 57.0, 0.9, and 39.3%, respectively. A comparison of samples at different time points (4, 5, and 6 months) showed a progressive increase in the proportion of bone with a decrease in the proportion of dentin. The bone was compact with normal osteocytes and moderate osteoblastic activity. In 4 out of 10 samples, no dentin was observed; in the other samples, it represented 1-5% (with geometric fragments). CONCLUSIONS: Dentin block showed to be a suitable bone substitute in an alveolar ridges preservation model. CLINICAL RELEVANCE: The promising results of dentin block as a bone substitute in alveolar ridge preservation could have an important clinical impact considering this biomaterial brings together the regenerative potential of three autologous products with excellent biological and clinical behavior, low risk of adverse effects, and feasible acquisition.


Assuntos
Aumento do Rebordo Alveolar , Substitutos Ósseos/uso terapêutico , Dentina/química , Fibrinogênio/química , Fibrina Rica em Plaquetas/química , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Extração Dentária , Alvéolo Dental
13.
J Cachexia Sarcopenia Muscle ; 10(5): 1045-1059, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31273954

RESUMO

BACKGROUND: Cachexia is a paraneoplastic syndrome related with poor prognosis. The tumour micro-environment contributes to systemic inflammation and increased oxidative stress as well as to fibrosis. The aim of the present study was to characterise the inflammatory circulating factors and tumour micro-environment profile, as potentially contributing to tumour fibrosis in cachectic cancer patients. METHODS: 74 patients (weight stable cancer n = 31; cachectic cancer n = 43) diagnosed with colorectal cancer were recruited, and tumour biopsies were collected during surgery. Multiplex assay was performed to study inflammatory cytokines and growth factors. Immunohistochemistry analysis was carried out to study extracellular matrix components. RESULTS: Higher protein expression of inflammatory cytokines and growth factors such as epidermal growth factor, granulocyte-macrophage colony-stimulating factor, interferon-α, and interleukin (IL)-8 was observed in the tumour and serum of cachectic cancer patients in comparison with weight-stable counterparts. Also, IL-8 was positively correlated with weight loss in cachectic patients (P = 0.04; r = 0.627). Immunohistochemistry staining showed intense collagen deposition (P = 0.0006) and increased presence of α-smooth muscle actin (P < 0.0001) in tumours of cachectic cancer patients, characterizing fibrosis. In addition, higher transforming growth factor (TGF)-ß1, TGF-ß2, and TGF-ß3 expression (P = 0.003, P = 0.05, and P = 0.047, respectively) was found in the tumour of cachectic patients, parallel to p38 mitogen-activated protein kinase alteration. Hypoxia-inducible factor-1α mRNA content was significantly increased in the tumour of cachectic patients, when compared with weight-stable group (P = 0.005). CONCLUSIONS: Our results demonstrate TGF-ß pathway activation in the tumour in cachexia, through the (non-canonical) mitogen-activated protein kinase pathway. The results show that during cachexia, intratumoural inflammatory response contributes to the onset of fibrosis. Tumour remodelling, probably by TGF-ß-induced transdifferentiation of fibroblasts to myofibroblasts, induces unbalanced inflammatory cytokine profile, angiogenesis, and elevation of extracellular matrix components (EMC). We speculate that these changes may affect tumour aggressiveness and present consequences in peripheral organs.


Assuntos
Caquexia/etiologia , Caquexia/metabolismo , Neoplasias/complicações , Neoplasias/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Idoso , Biomarcadores , Biópsia , Composição Corporal , Índice de Massa Corporal , Caquexia/patologia , Células Cultivadas , Citocinas/metabolismo , Feminino , Fibroblastos , Fibrose , Expressão Gênica , Humanos , Hipóxia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Estresse Oxidativo , Microambiente Tumoral
14.
Naturwissenschaften ; 106(7-8): 32, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31183554

RESUMO

Animals frequently use agonistic contests as a way to solve disputes over indivisible resources. Such agonistic contests often represent interactions between an owner and a non-owner of a resource. However, some behaviors adopted by rivals during agonistic interactions are similar to behaviors adopted in other types of interactions. Thus, the possibility exists that some interactions between individuals can be misinterpreted as actual agonistic contests. Herein, we synthesize information from prior studies that present interactions that may be confounded with actual agonistic contests. We also point potential problems when different types of confoundment occur and provide suggestions of how to distinguish between agonistic contests and alternative interactions. For this, we made a distinction between completely non-agonistic interactions and quasi-agonistic interactions (i.e., interactions in which at least one rival is not motivated to fight). We also show potential biases in the understanding of how rivals decide who is the winner of a contest for studies that consider non- or quasi-agonistic interactions as actual agonistic contests.


Assuntos
Comportamento Agonístico , Ecologia/métodos , Animais
15.
Biol Rev Camb Philos Soc ; 94(4): 1430-1442, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30916473

RESUMO

Since the 1970's, models based on evolutionary game theory, such as war of attrition (WOA), energetic war of attrition (E-WOA), cumulative assessment model (CAM) and sequential assessment model (SAM), have been widely applied to understand how animals settle contests. Despite the important theoretical advances provided by these models, empirical evidence indicates that rules adopted by animals to settle contests vary among species. This stimulated recent discussions about the generality and applicability of models of contest. A meta-analysis may be helpful to answer questions such as: (i) is there a common contest rule to settle contests; (ii) do contest characteristics, such as the occurrence of physical contact during the fight, influence the use of specific contest rules; and (iii) is there a phylogenetic signal behind contest rules? To answer these questions, we gathered information on the relationship between contest duration and traits linked to contestants' resource holding potential (RHP) for randomly paired rivals and RHP-matched rivals. We also gathered behavioural data about contest escalation and RHP asymmetry. In contests between randomly paired rivals, we found a positive relationship between contest duration and loser RHP but did not find any pattern for winners. We also found a low phylogenetic signal and a similar response for species that fight with and without physical contact. In RHP-matched rivals, we found a positive relationship between contest duration and the mean RHP of the pair. Finally, we found a negative relation between contest escalation and RHP asymmetry, even though it was more variable than the other results. Our results thus indicate that rivals settle contests following the rules predicted by WOA and E-WOA in most species. However, we also found inconsistencies between the behaviours exhibited during contests and the assumptions of WOA models in most species. We discuss additional (and relatively untested) theoretical possibilities that may be explored to resolve the existing inconsistencies.


Assuntos
Agressão/fisiologia , Comportamento Animal/fisiologia , Comportamento Competitivo , Modelos Biológicos , Animais
17.
Platelets ; 29(5): 468-475, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28727481

RESUMO

Chronic wounds (VLU: venous leg ulcer, DFU: diabetic foot ulcer, PU: pressure ulcer, or complex wounds) affect a significant proportion of the population. Despite appropriate standard wound care, such ulcers unfortunately may remain open for months or even years. The use of leukocyte- and platelet-rich fibrin (L-PRF) to cure skin ulcers is a simple and inexpensive method, widely used in some countries but unknown or neglected in most others. This auto-controlled prospective cohort study explored and quantified accurately for the first time the adjunctive benefits of topical applications of L-PRF in the management of such refractory ulcers in a diverse group of patients. Forty-four consecutive patients with VLUs (n = 28, 32 wounds: 17 ≤ 10 cm2 and 15 > 10 cm2), DPUs (n = 9, 10 wounds), PUs (n = 5), or complex wounds (n = 2), all refractory to standard treatment for ≥3 months, received a weekly application of L-PRF membranes. L-PRF was prepared following the original L-PRF method developed more than 15 years ago (400g, 12 minutes) using the Intra-Spin L-PRF centrifuge/system and the XPression box kit (Intra-Lock, Boca Raton, FL, USA; the only CE/FDA cleared system for the preparation of L-PRF). Changes in wound area were recorded longitudinally via digital planimetry. Adverse events and pain levels were also registered. All wounds showed significant improvements after the L-PRF therapy. All VLUs ≤ 10 cm2, all DFUs, as well as the two complex wounds showed full closure within a 3-month period. All wounds of patients with VLUs > 10 cm2 who continued therapy (10 wounds) could be closed, whereas in the five patients who discontinued therapy improvement of wound size was observed. Two out of the five PUs were closed, with improvement in the remaining three patients who again interrupted therapy (surface evolution from 7.35 ± 4.31 cm2 to 5.78 ± 3.81 cm2). No adverse events were observed. A topical application of L-PRF on chronic ulcers, recalcitrant to standard wound care, promotes healing and wound closure in all patients following the treatment. This new therapy is simple, safe and inexpensive, and should be considered a relevant therapeutic option for all refractory skin ulcers.


Assuntos
Úlcera da Perna/terapia , Leucócitos/metabolismo , Fibrina Rica em Plaquetas/metabolismo , Medicina Regenerativa/métodos , Estudos de Coortes , Feminino , Humanos , Úlcera da Perna/patologia , Masculino , Estudos Prospectivos
18.
J Endod ; 43(11): 1828-1834, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28965773

RESUMO

Regenerative endodontic procedures (REPs) associated with apical surgery could represent an alternative treatment strategy for patients whose teeth present incomplete root formation and extensive apical lesions. Leukocyte platelet-rich fibrin (L-PRF) has potential benefits in REPs; it could promote apical root formation and optimal bone healing. The aim of this case report was to describe innovative regenerative endodontic therapy using L-PRF in the root canal and an extensive apical lesion in an immature tooth with dens invaginatus and asymptomatic apical periodontitis. A healthy 20-year-old woman was referred to the dental clinic of the Universidad de Los Andes, Santiago, Chile, for endodontic treatment in tooth # 22 with incomplete root development and an extensive apical lesion. The diagnosis was asymptomatic apical periodontitis associated with dens invaginatus type II. The patient was treated with an innovative approach using L-PRF in REPs associated with apical surgery. Follow-ups were performed at 6 months and 1 year later. They included periapical radiographs, cone-beam computed tomographic imaging, sensitivity, and vitality tests. The clinical evaluations performed at 6 months and 1 year revealed an absence of symptoms. The radiographic evaluations showed that the apical lesion was resolved. The cone-beam images indicated that the root length increased and the walls had thickened. The sensitivity tests were positive, and the laser Doppler flowmetry showed positive blood flow after 1 year. The success of the results in this case report indicate that L-PRF can be used as a complement in apical surgery and REPs and could provide an innovative alternative treatment strategy for complex clinical cases like these.


Assuntos
Regeneração Tecidual Guiada/métodos , Leucócitos/fisiologia , Fibrina Rica em Plaquetas/fisiologia , Ápice Dentário/fisiologia , Terapia Combinada , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Periodontite Periapical/diagnóstico por imagem , Periodontite Periapical/cirurgia , Radiografia Dentária , Regeneração , Ápice Dentário/diagnóstico por imagem , Ápice Dentário/cirurgia , Adulto Jovem
19.
Sci Rep ; 7: 46452, 2017 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-28401929

RESUMO

More insight into the biological fundamentals of leukocyte platelet-rich fibrin (L-PRF) guided healing is necessary to recommend its application, in particular in deficient bone sites that need to support implants. This study investigated the short-term bone healing effect of L-PRF treatment in cylindrical non-critical sized bone defects with 3 mm diameter and 6 mm depth in tibiae of 18 adult male New Zealand White rabbits. After a randomization process, 96 bone defects were prepared and half of them were filled with a L-PRF membrane, while untreated defects in the opposite tibia served as control group. The rabbits were euthanized after 7, 14 or 28 days of healing. The bone healing of the cortical and medullary areas was investigated by micro-CT, while the expression of molecular markers (RUNX2, VEGFA, COL1A2 and BMP2) was assessed by qRT-PCR. Treatment with L-PRF did not affect the micro-structural bone characteristics of the repaired bone tissue, except for a decrease in the trabecular connectivity at the cortical level after 14 days of healing. At this time, RUNX2 and VEGFA mRNA levels were significantly lower in the treated defects. L-PRF membranes thus had a temporary negative influence on the bone microarchitecture (Tb.Pf) and on the RUNX2 and VEGFA expression during early bone healing. Overall, L-PRF treatment did not enhance bone regeneration in these non-critical size defects after 28 days.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Leucócitos , Fibrina Rica em Plaquetas , Tíbia/lesões , Cicatrização/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 2/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Coelhos , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Microtomografia por Raio-X
20.
Int J Otolaryngol ; 2017: 1231870, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29348753

RESUMO

BACKGROUND: Reconstruction of surgical defects following cranial base surgery is challenging. Others have demonstrated that leukocyte-platelet-rich fibrin (L-PRF) stimulates tissue healing and bone regeneration. However, these studies have addressed mostly maxillofacial surgical wounds. OBJECTIVE: The objective of this study was to assess the possible adjuvant role of L-PRF in inducing neoossification of the surgical bone defect in anterior skull base surgery. METHODS: We identified patients who had undergone an endoscopic endonasal surgery of the anterior skull base in which L-PRF membranes were used for the reconstruction of the bone defect and who were followed up with postoperative CT scans. CT findings were then correlated with baseline scans and with the CT scans of a patient who had undergone imaging and histologic analysis after maxillofacial surgery in which L-PRF was used and in which we demonstrated bone formation. RESULTS: Five patients fulfilled the inclusion criteria. In four patients, the CT scan demonstrated closure of the bony defect by neoosteogenesis; however, the bone appeared less dense than the surrounding normal bone. A comparison with the control patient yielded similar radiological features. CONCLUSION: This case series suggests that L-PRF may induce bone healing and regeneration at the surgical site defect. Multi-institutional studies with a larger series of patients are required to confirm this possibility.

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