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1.
J Appl Oral Sci ; 32: e20230458, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38922241

RESUMO

OBJECTIVE: This study compared three protocols for developing artificial white spot lesions (WSL) using biofilm models. METHODOLOGY: In total, 45 human enamel specimens were sterilized and allocated into three groups based on the biofilm model: Streptococcus sobrinus and Lactobacillus casei (Ss+Lc), Streptococcus sobrinus (Ss), or Streptococcus mutans (Sm). Specimens were incubated in filter-sterilized human saliva to form the acquired pellicle and then subjected to the biofilm challenge consisting of three days of incubation with bacteria (for demineralization) and one day of remineralization, which was performed once for Ss+Lc (four days total), four times for Ss (16 days total), and three times for Sm (12 days total). After WSL creation, the lesion fluorescence, depth, and chemical composition were assessed using Quantitative Light-induced Fluorescence (QLF), Polarized Light Microscopy (PLM), and Raman Spectroscopy, respectively. Statistical analysis consisted of two-way ANOVA followed by Tukey's post hoc test (α=0.05). WSL created using the Ss+Lc protocol presented statistically significant higher fluorescence loss (ΔF) and integrated fluorescence (ΔQ) in comparison to the other two protocols (p<0.001). RESULTS: In addition, Ss+Lc resulted in significantly deeper WSL (137.5 µm), followed by Ss (84.1 µm) and Sm (54.9 µm) (p<0.001). While high mineral content was observed in sound enamel surrounding the WSL, lesions created with the Ss+Lc protocol showed the highest demineralization level and changes in the mineral content among the three protocols. CONCLUSION: The biofilm model using S. sobrinus and L. casei for four days was the most appropriate and simplified protocol for developing artificial active WSL with lower fluorescence, higher demineralization, and greater depth.


Assuntos
Biofilmes , Cárie Dentária , Esmalte Dentário , Lacticaseibacillus casei , Streptococcus mutans , Humanos , Streptococcus mutans/fisiologia , Cárie Dentária/microbiologia , Cárie Dentária/terapia , Esmalte Dentário/microbiologia , Esmalte Dentário/química , Lacticaseibacillus casei/fisiologia , Fatores de Tempo , Reprodutibilidade dos Testes , Streptococcus sobrinus/fisiologia , Análise Espectral Raman , Análise de Variância , Microscopia de Polarização , Estatísticas não Paramétricas , Remineralização Dentária/métodos , Valores de Referência , Saliva/microbiologia , Saliva/química , Desmineralização do Dente/microbiologia , Fluorescência
2.
J Clin Med ; 13(12)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38930099

RESUMO

Background and Objectives: Management of acetabular fractures is aimed at anatomically reducing and fixing all displaced or unstable fractures, as the accuracy of fracture reduction has been demonstrated to strongly correlate with clinical outcomes. However, there is a noticeable gap in the literature concerning the perioperative and postoperative care of patients with acetabular fractures, which ultimately can be potential risk factors for adverse outcomes and permanent disabilities. This study aimed to systematically review the available literature regarding rehabilitation practices, including weight-bearing protocols, across time points in surgically treated acetabular fracture patients and correlate these practices with functional outcomes. Methods: We systematically reviewed the Medline and PubMed databases and the Cochrane Central Register of Controlled Trials in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The inclusion criteria were studies with adult patients (19+ years), publications from the last 10 years, articles focusing on rehabilitation or mentioning any aspect related to rehabilitation (such as weight-bearing or muscle training), and describing the surgical management of acute, isolated acetabulum fractures. Specific information was collected, including the fracture classification, time to surgery, surgical approach, surgical time, blood loss, fixation strategy, quality of reduction, postoperative rehabilitation protocol, complication rate, type(s) of complication, and outcome measurement(s). The choice(s) of surgical approach, surgical time, blood loss, and fixation strategy were stratified based on the fracture classification. The complication rate and type(s) of complication were calculated for all studies. Fractures were classified based on the Letournel classification. Results: A total of 494 articles were identified from the initial search, of which 22 (1025 patients) were included in the final review. The most common rehabilitation protocol favored isometric quadriceps and abductor strengthening exercises starting on the first postoperative day, with passive hip movement at 1-3 days postoperatively and active hip movement ranging from the first postoperative day to 4 weeks postoperatively. Partial weight-bearing with a walker or a pair of crutches was permitted from 1 to 12 weeks after surgery, and full weight-bearing was allowed depending on the patient's general condition and fracture healing state (generally at the end of 3 months). In only three studies did the patients start bearing weight in the early postoperative period (≤1 week). Meta-regression analysis was not performed due to the discrepancy between studies that reported a weight-bearing protocol ≤1 week and >1 week postoperatively. Conclusions: Our study suggests that an accelerated postoperative rehabilitation protocol, including early permissive weight-bearing, does not appear to increase the risk of loss of reduction or the rate of complications after surgical treatment of acetabular fractures. However, a proper meta-analysis was not possible, and the heterogeneity of the included studies did not allow us to conclude anything about the potential biomechanical and clinical benefits nor the negative effects related to this rehabilitation regimen in terms of functional results. There is an inconsistent use of PROMs for objectively calculating the effect size of the accelerated protocol compared with restricted weight-bearing regimes. We pose the need for higher-level evidence to proof our hypothesis.

3.
Microbiol Resour Announc ; 13(7): e0042224, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38832805

RESUMO

Here, we report 27 metagenome-assembled bacterial genomes (MAGs) from litter samples of a secondary forest located in Brazil over an Amazonian Dark Earth pool. The data set includes members from the phyla Pseudomonadata (14 MAGs), Actinomycetota (7 MAGs), Bacteroidota (4 MAGs), Bacillota (1 MAG), and Bdellovibrionota (1 MAG).

4.
Int Orthop ; 48(5): 1351-1356, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38302595

RESUMO

In orthopaedic surgery, as well as other areas in medicine, it is common for a surgical technique to carry the original authors' name describing the procedure. The Judet family represents a unique history, since several orthopaedic procedures are known as "Judet's technique". The aim of this historic review is to outline the genealogy of the orthopaedic arm of the Judet family, while crediting each surgical procedure to the specific family member that described the technique.


Assuntos
Procedimentos Ortopédicos , Ortopedia , Humanos , Procedimentos Ortopédicos/efeitos adversos , Procedimentos Ortopédicos/métodos
5.
Braz J Microbiol ; 55(2): 1817-1828, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38358421

RESUMO

The Amazon rainforest, a hotspot for biodiversity, is a crucial research area for scientists seeking novel microorganisms with ecological and biotechnological significance. A key region within the Amazon rainforest is the Amazonian Dark Earths (ADE), noted for supporting diverse plant and microbial communities, and its potential as a blueprint for sustainable agriculture. This study delineates the isolation, morphological traits, carbon source utilization, and genomic features of Fictibacillus terranigra CENA-BCM004, a candidate novel species of the Fictibacillus genus isolated from ADE. The genome of Fictibacillus terranigra was sequenced, resulting in 16 assembled contigs, a total length of 4,967,627 bp, and a GC content of 43.65%. Genome annotation uncovered 3315 predicted genes, encompassing a wide range of genes linked to various metabolic pathways. Phylogenetic analysis indicated that CENA-BCM004 is a putative new species, closely affiliated with other unidentified Fictibacillus species and Bacillus sp. WQ 8-8. Moreover, this strain showcased a multifaceted metabolic profile, revealing its potential for diverse biotechnological applications. It exhibited capabilities to antagonize pathogens, metabolize multiple sugars, mineralize organic matter compounds, and solubilize several minerals. These insights substantially augment our comprehension of microbial diversity in ADE and underscore the potential of Fictibacillus terranigra as a precious resource for biotechnological endeavors. The genomic data generated from this study will serve as a foundational resource for subsequent research and exploration of the biotechnological capabilities of this newly identified species.


Assuntos
Composição de Bases , Genoma Bacteriano , Filogenia , Floresta Úmida , Genômica , RNA Ribossômico 16S/genética , Bacillaceae/genética , Bacillaceae/classificação , Bacillaceae/isolamento & purificação , Bacillaceae/metabolismo , Brasil , DNA Bacteriano/genética
6.
J. appl. oral sci ; J. appl. oral sci;32: e20230458, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564708

RESUMO

Abstract Creating artificial caries-like lesions that mimic the complex changes observed in natural caries is essential for properly evaluating new strategies, dental materials, and devices designed to arrest their progression and avoid more costly and invasive treatments. Objective This study compared three protocols for developing artificial white spot lesions (WSL) using biofilm models. Methodology In total, 45 human enamel specimens were sterilized and allocated into three groups based on the biofilm model: Streptococcus sobrinus and Lactobacillus casei (Ss+Lc), Streptococcus sobrinus (Ss), or Streptococcus mutans (Sm). Specimens were incubated in filter-sterilized human saliva to form the acquired pellicle and then subjected to the biofilm challenge consisting of three days of incubation with bacteria (for demineralization) and one day of remineralization, which was performed once for Ss+Lc (four days total), four times for Ss (16 days total), and three times for Sm (12 days total). After WSL creation, the lesion fluorescence, depth, and chemical composition were assessed using Quantitative Light-induced Fluorescence (QLF), Polarized Light Microscopy (PLM), and Raman Spectroscopy, respectively. Statistical analysis consisted of two-way ANOVA followed by Tukey's post hoc test (α=0.05). WSL created using the Ss+Lc protocol presented statistically significant higher fluorescence loss (ΔF) and integrated fluorescence (ΔQ) in comparison to the other two protocols (p<0.001). Results In addition, Ss+Lc resulted in significantly deeper WSL (137.5 µm), followed by Ss (84.1 µm) and Sm (54.9 µm) (p<0.001). While high mineral content was observed in sound enamel surrounding the WSL, lesions created with the Ss+Lc protocol showed the highest demineralization level and changes in the mineral content among the three protocols. Conclusion The biofilm model using S. sobrinus and L. casei for four days was the most appropriate and simplified protocol for developing artificial active WSL with lower fluorescence, higher demineralization, and greater depth.

7.
Diagnostics (Basel) ; 13(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38066761

RESUMO

Introduction: We investigated the biomechanical behaviour of different fixations of the tibial posterior malleolus (TPM), simulating distinct situations of involvement of the tibiotalar articular surface (TTAS) through a finite element model (FEM). Material and methods: A 3D computer-aided design model of the left ankle was obtained. The materials used were divided according to their characteristics into ductile and non-ductile, and all materials were assumed to be linear elastic, isotropic, and homogenous. Three different fracture lines of the TPM were defined, with sagittal angles of 10°, 25°, and 45°. For biomechanical comparison, different constructions using a trans-syndesmotic screw (TSS) only (Group T), a one-third tubular plate only with (Group PT) and without (Group PS) a TSS, and a locked compression plate with (Group LCPT) and without (Group LCPS) a TSS were tested. FEM was used to simulate the boundary conditions of vertical loading. Load application regions were selected in the direction of the 700 N Z-axis, 90% on the tibia and 10% on the fibula. Data on the displacement and stress in the FEM were collected, including the total principal maximum (MaxT) and total principal minimum (MinT) for non-ductile materials, total displacement (desT), localized displacement at the fragment (desL), localized displacement at syndesmosis (desS), and Von Mises equivalent stress for ductile materials. The data were analysed using ANOVA and multiple comparison LSD tests were used. Results: For TPM fractures with sagittal angles 10° and 25°, desL in the PT and LCP groups was significantly lower, as well as Von Mises stress in Group LCPT in 10°, and PT and LCPT groups in 25°. For TPM fractures with a sagittal angle of 45°, desL in the LCP group and Von Mises stress in Group LCPS and LCPT were significantly lower. We found that any TPM fracture may indicate instability of the distal tibiofibular syndesmosis, even when the fragment is small. Conclusion: Our study showed that in fragments involving 10% of the TTAS, the use of a TSS is sufficient, but when the involvement is greater than 25% of the TTAS, either a non-locked or locked plate must be used to buttress the TPM. In posterior fragments affecting 45% or more of the TTAS, the use of a locking plate is recommended.

8.
Polymers (Basel) ; 15(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38139897

RESUMO

Microplastic pollution is a growing public concern as these particles are ubiquitous in various environments and can fragment into smaller nanoplastics. Another environmental concern arises from widely used engineered nanoparticles. Despite the increasing abundance of these nano-sized pollutants and the possibility of interactions with organisms at the sub cellular level, with many risks still being unknown, there are only a few publications on this topic due to the lack of reliable techniques for nanoparticle characterization. We propose a multi-technique approach for the characterization of nanoparticles down to the 10 nm level using standard micro-Raman spectroscopy combined with standard atomic force microscopy. We successfully obtained single-particle spectra from 25 nm sized polystyrene and 9 nm sized TiO2 nanoparticles with corresponding mass limits of detection of 8.6 ag (attogram) and 1.6 ag, respectively, thus demonstrating the possibility of achieving an unambiguous Raman signal from a single, small nanoparticle with a resolution comparable to more complex and time-consuming technologies such as Tip-Enhanced Raman Spectroscopy and Photo-Induced Force Microscopy.

9.
PLoS One ; 18(12): e0293518, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38109440

RESUMO

This paper examines scaling behaviors of urban landscape and street design metrics with respect to city population in Latin America. We used data from the SALURBAL project, which has compiled and harmonized data on health, social, and built environment for 371 Latin American cities above 100,000 inhabitants. These metrics included total urbanized area, effective mesh size, area in km2 and number of streets. We obtained scaling relations by regressing log(metric) on log (city population). The results show an overall sub-linear scaling behavior of most variables, indicating a relatively lower value of each variable in larger cities. We also explored the potential influence of colonization on the current built environment, by analyzing cities colonized by Portuguese (Brazilian cities) or Spaniards (Other cities in Latin America) separately. We found that the scaling behaviors are similar for both sets of cities.


Assuntos
População Urbana , Humanos , Cidades , América Latina/epidemiologia , Brasil
10.
Microbiol Resour Announc ; 12(11): e0057423, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37811974

RESUMO

Here, we report 10 distinct bacterial genomes from Amazonian dark earths, including six identified as Paenibacillus polymyxa, while the remaining four were unique representatives of Paenibacillus vini, Bacillus cereus, Brevibacillus agri, and Fictibacillus sp., respectively. Each strain exhibited antagonistic activity against Fusarium oxysporum, underscoring their potential as sustainable agriculture resources.

11.
Radiat Res ; 200(4): 366-373, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37772737

RESUMO

Radiotherapy is a well-established cancer treatment; it is estimated that approximately 52% of oncology patients will require this treatment modality at least once. However, some tumors, such as triple-negative breast cancer (TNBC), may present as radioresistant and thus require high doses of ionizing radiation and a prolonged period of treatment, which may result in more severe side effects. Moreover, such tumors show a high incidence of metastases and decreased survival expectancy of the patient. Thus, new strategies for radiosensitizing TNBC are urgently needed. Red light therapy, photobiomodulation, has been used in clinical practice to mitigate the adverse side effects usually associated with radiotherapy. However, no studies have explored its use as a radiosensitizer of TNBC. Here, we used TNBC-bearing mice as a radioresistant cancer model. Red light treatment was applied in three different protocols before a high dose of radiation (60 Gy split in 4 fractions) was administered. We evaluated tumor growth, mouse clinical signs, total blood cell counts, lung metastasis, survival, and levels of glutathione in the blood. Our data showed that the highest laser dose in combination with radiation arrested tumor progression, likely due to inhibition of GSH synthesis. In addition, red light treatment before each fraction of radiation, regardless of the light dose, improved the health status of the animals, prevented anemia, reduced metastases, and improved survival. Collectively, these results indicate that red light treatment in combination with radiation could prove useful in the treatment of TNBC.


Assuntos
Radiossensibilizantes , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/radioterapia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Modelos Animais de Doenças , Linhagem Celular Tumoral , Radiossensibilizantes/farmacologia , Luz
12.
PLoS One ; 18(8): e0288515, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37561781

RESUMO

Urban parks have been studied for their effects on health and the environment. Accessing park data from reliable and comparable sources remains challenging, reinforcing the importance of standardized search tools, notably in Latin America. We designed a systematized methodology to identify processes of accessing, collecting, verifying, and harmonizing urban park spatial data in all Brazilian capitals included in the Urban Health in Latin America (SALURBAL) project. We developed a research protocol using official and non-official sources combining the results of Google Maps (GMaps) points and OpenStreetMap (OSM) polygons-GMaps-OSM. Descriptive analyses included the frequency of the distribution of parks before and after harmonization stratified by data source. We used the intraclass correlation coefficient (ICC) to assess agreement in the area between official and GMaps-OSM data. Official data were obtained for 16 cities; for the remaining 11 capitals, we used GMaps-OSM. After verification and harmonization, 302 urban parks were obtained from official data and 128 from GMaps-OSM. In a sub-study of the 16 cities with official data (n = 302 parks), we simulated a collection of non-official data using GMaps-OSM and OSM only. From GMaps-OSM, we obtained 142 parks, and from OSM, 230 parks. Statistical analysis showed a better agreement between official data and OSM. After completing verification and harmonization, the complete dataset (official and GMaps-OSM) included 430 urban parks with a total area of 145.14 km2. The mean number of parks across cities was 16, with a mean size area of 0.33 km2. The median number of parks was nine, with a median area of 0.07 km2. This study highlights the importance of creating mechanisms to access, collect, harmonize, and verify urban park data, which is essential for examining the impact of parks on health. It also stresses the importance of providing reliable urban park spatial data for city officials.


Assuntos
Parques Recreativos , Saúde da População Urbana , Humanos , Brasil , Cidades , Coleta de Dados , População Urbana
13.
J Fungi (Basel) ; 9(7)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37504706

RESUMO

In recent years, Candida auris has emerged as a hazardous hospital-acquired pathogen. Its resistance to antifungal treatments makes it challenging, requiring new approaches to manage it effectively. Herein, we aimed to assess the impact of photodynamic inactivation mediated by methylene blue (MB-PDI) or 1,9-dimethyl MB (DMMB-PDI) combined with a red LED against C. auris. To evaluate the photoinactivation of yeasts, we quantified colony-forming units and monitored ROS production. To gain some insights into the differences between MB and DMMB, we assessed lipid peroxidation (LPO) and mitochondrial membrane potential (ΔΨm). After, we verified the effectiveness of DMMB against biofilms by measuring metabolic activity and biomass, and the structures were analyzed through scanning electron microscopy and optical coherence tomography. We also evaluated the cytotoxicity in mammalian cells. DMMB-PDI successfully eradicated C. auris yeasts at 3 µM regardless of the light dose. In contrast, MB (100 µM) killed cells only when exposed to the highest dose of light. DMMB-PDI promoted higher ROS, LPO and ΔΨm levels than those of MB. Furthermore, DMMB-PDI was able to inhibit biofilm formation and destroy mature biofilms, with no observed toxicity in fibroblasts. We conclude that DMMB-PDI holds great potential to combat the global threat posed by C. auris.

14.
Rev Bras Ortop (Sao Paulo) ; 58(3): 507-513, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37396077

RESUMO

Objective To evaluate the biomechanical capacity of two forms of fixation for Pipkin type-II fractures, describing the vertical fracture deviation, the maximum and minimum principal stresses, and the Von Mises equivalent stress in the syntheses used. Materials and Methods Two internal fasteners were developed to treat Pipkin type-II fractures through finite elements: a 3.5-mm cortical screw and a Herbert screw. Under the same conditions, the vertical fracture deviation, the maximum and minimum principal stresses, and the Von Mises equivalent stress in the syntheses used were evaluated. Results The vertical displacements evaluated were of 1.5 mm and 0.5 mm. The maximum principal stress values obtained in the upper region of the femoral neck were of 9.7 KPa and 1.3 Kpa, and the minimum principal stress values obtained in the lower region of the femoral neck were of -8.7 KPa and -9.3 KPa. Finally, the peak values for Von Mises stress were of 7.2 GPa and 2.0 GPa for the fixation models with the use of the 3.5-mm cortical screw and the Herbert screw respectively. Conclusion The fixation system with the Herbert screw generated the best results in terms of reduction of vertical displacement, distribution of the maximum principal stress, and the peak Von Mises equivalent stress, demonstrating mechanical superiority compared to that of the 3.5-mm cortical screw in the treatment of Pipkin type-II fractures.

15.
Eur J Trauma Emerg Surg ; 49(5): 2057-2069, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37160440

RESUMO

PURPOSE: To systematically review the currently available existing evidence related to the presentation and management of simultaneous floating hip and knee injuries to identify injury characteristics, treatment strategies, and complications. METHODS: Data sources: Relevant articles were identified by searching Medline, PubMed, and Google Scholar databases with no language restrictions. Manual searches of other relevant databases (SciELO and grey literature databases) and reference lists of primary articles found from initial searches were also conducted. STUDY SELECTION: All types of study designs published from January 1st, 2000 to October 1st, 2022 involving skeletally mature patients with simultaneous floating hip and knee injuries were included. DATA EXTRACTION: Basic information and specific injury-related information were collected. RESULTS: Eight case reports were included. No study adequately reported the case with sufficient detail to allow other investigators to make inferences, nor was the result properly calculated, nor was the follow-up considered adequate for adequate functional assessment to occur in 80% of the studies. CONCLUSION: The exact treatment strategy and the follow-up time are not uniform across the included studies; therefore, they are not sufficient to adequately recommend surgical approach, timing of fixation, and fixation method. Our findings warrant the need for better documentation and reporting information about the mode of treatment of simultaneous floating hip and knee injuries.


Assuntos
Traumatismos do Joelho , Articulação do Joelho , Humanos , Articulação do Joelho/cirurgia , Traumatismos do Joelho/cirurgia , Fixação de Fratura/métodos , Extremidades
16.
Acta Ortop Bras ; 31(2): e259557, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37151730

RESUMO

Objective: To determine, by biomechanical analysis, safe patellar cut limits in anterior cruciate ligament (ACL) reconstruction that minimize fracture risks. Methods: From three-dimensional reconstruction, triangular cuts were made in the patella, with a depth of 6.5 mm and variable width and length (10 to 20 mm and 8 to 12 mm, respectively, both with an interval of 1 mm). The combinations of cuts constituted 55 models for tests, with five variations in width and 11 variations in length, tested with the finite element method (FEM). Results: The mean of the localized principal maximum (traction force) values was 4.36 Pa (SD 0.87 ± 0.76) and the localized principal minimum (compression force) was -4.33 Pa (SD 1.05 ± 1.11). Comparing width and length to the tension force of the values of the main maximum, we found statistical significance from 11 mm for width and 13 mm for length. Conclusion: In ACL reconstruction, the removal of the patellar bone fragment is safe for fragments smaller than 11 mm in width and 13 mm in length, which corresponds to 24% of the width and 28% of the length of the patella used. Level of Evidence II, Comparative Prospective Study.


Objetivo: Determinar, por meio de análise biomecânica, os limites de corte patelar seguros para a reconstrução do ligamento cruzado anterior (LCA) e que minimizem riscos de fratura. Métodos: A partir de reconstrução tridimensional, foram feitos cortes triangulares na patela, com profundidade de 6,5 mm e largura e comprimento variáveis (8 a 12 mm e 10 a 20 mm), respectivamente, com intervalo de 1 mm). As combinações dos cortes constituíram 55 modelos para ensaios, com 5 variações de largura e 11 variações de comprimento, ensaiados por meio do método dos elementos finitos (MEF). Resultados: A média dos valores da máxima principal localizada (força de tração) foi de 4,36 Pa (DP 0,87 ± 0,76), e a mínima principal localizada (força de compressão) foi de −4,33 Pa (DP 1,05 ± 1,11). Comparando largura e comprimento à força de tensões dos valores da máxima principal, houve significância estatística a partir de 11 mm para largura e 13 mm para comprimento. Conclusão: Na reconstrução do LCA, a retirada do fragmento ósseo patelar mostrou-se segura para fragmentos menores que 11 mm de largura e 13 mm de comprimento, o que corresponde a 24% da largura e 28% do comprimento da patela utilizada. Nível de Evidência II, Estudo Prospectivo Comparativo.

17.
Rev. Bras. Ortop. (Online) ; 58(3): 507-513, May-June 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1449817

RESUMO

Abstract Objective To evaluate the biomechanical capacity of two forms of fixation for Pipkin type-II fractures, describing the vertical fracture deviation, the maximum and minimum principal stresses, and the Von Mises equivalent stress in the syntheses used. Materials and Methods Two internal fasteners were developed to treat Pipkin type-II fractures through finite elements: a 3.5-mm cortical screw and a Herbert screw. Under the same conditions, the vertical fracture deviation, the maximum and minimum principal stresses, and the Von Mises equivalent stress in the syntheses used were evaluated. Results The vertical displacements evaluated were of 1.5mm and 0.5mm. The maximum principal stress values obtained in the upper region of the femoral neck were of 9.7 KPa and 1.3 Kpa, and the minimum principal stress values obtained in the lower region of the femoral neck were of-8.7 KPa and -9.3 KPa. Finally, the peak values for Von Mises stress were of 7.2 GPa and 2.0 GPa for the fixation models with the use of the 3.5-mm cortical screw and the Herbert screw respectively. Conclusion The fixation system with the Herbert screw generated the best results in terms of reduction of vertical displacement, distribution of the maximum principal stress, and the peak Von Mises equivalent stress, demonstrating mechanical superiority compared to that of the 3.5-mm cortical screw in the treatment of Pipkin type-II fractures.


Resumo Objetivo Avaliar a capacidade biomecánica de duas formas de fixação de fraturas tipo II de Pipkin descrevendo o desvio da fratura no sentido vertical, as tensões máxima e mínima principais, e a tensão equivalente de Von Mises nas sínteses utilizadas. Materiais e Métodos Dois fixadores internos foram desenvolvidos para tratar a fratura tipo II de Pipkin por meio de elementos finitos: parafuso cortical de 3,5 mm e parafuso de Herbert. Sob as mesmas condições, foram avaliados o desvio da fratura no sentido vertical, as tensões máxima e mínima principais, e a tensão equivalente de Von Mises nas sínteses utilizadas. Resultados Os deslocamentos verticais avaliados foram de 1,5 mm e 0,5 mm. Os valores de tensão máxima obtidos na região superior do colo femoral foram de 9,7 KPa e 1,3 KPa, e os valores de tensão mínima obtidos na região inferior do colo femoral foram de -8,7KPa e -9,3 KPa. Por fim, os valores de pico da tensão equivalente de Von Misesforam de 7,2 GPa e2,0 GPa paraosmodelos de fixação com o uso do parafuso cortical de 3,5 mm e do parafuso de Herbert, respectivamente. Conclusão Osistema de fixação com parafuso de Herbert gerou os melhores resultados em termos de redução do deslocamento vertical, distribuição da tensão máxima e do pico da tensão equivalente de Von Mises, o que demonstra sua superioridade mecânica comparada à do parafuso cortical de 3,5 mm no tratamento da fratura tipo II de Pipkin.


Assuntos
Humanos , Parafusos Ósseos , Cabeça do Fêmur/cirurgia , Fraturas do Quadril/cirurgia
18.
Nanomaterials (Basel) ; 13(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36839111

RESUMO

Nd3+-doped GeO2-PbO glass with silver (Ag) nanoparticles (NPs) are produced with double line waveguides through fs laser processing for photonic applications. A Ti:sapphire fs laser at 800 nm was used to write the waveguides directly into the glass 0.7 mm beneath the surface. This platform is based on pairs of parallel lines with spacing of 10 µm, each pair being formed by two identical written lines but in two different configurations of 4 or 8 separately processed lines, which are coincident. The results of optical microscopy, absorbance measurements, refractive index change, beam quality factor (at 632 and 1064 nm), photoluminescence, propagation losses, and relative gain at 1064 nm are presented. The structural changes in the glass due to the presence of Ag NPs were investigated by Raman spectroscopy. At 632 and 1064 nm, x,y-symmetrical guiding was observed, and for both kinds of overlapping pulses, a refractive index alteration of 10-3 was found in both directions. Photoluminescence growth of ~47% at 1064 nm was observed due to the plasmonic effect of Ag NPs. In dual waveguides containing Ag NPs, the relative gain obtained increased by 40% and 30% for four and eight overlapping lines, respectively, at 600 mW of 808 nm pump power, when compared to waveguides without those metallic NPs. We highlight the resultant positive internal gains of 5.11 and 7.12 dB/cm that showed a growth of ~40% and ~30%, respectively, with respect to the samples without Ag NPs. The increase in photoluminescence and relative gain were related to the local field growth produced by Ag NPs. The present results show that the addition of Ag NPs impacts positively on the optical performance at 1064 nm of double line waveguides processed by fs laser writing in Nd3+-doped GeO2-PbO glass, opening news perspectives for photonics.

19.
Probiotics Antimicrob Proteins ; 15(2): 287-299, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-34420188

RESUMO

Lectins are carbohydrate-binding proteins with several bioactivities, including antimicrobial properties. Portulaca elatior is a species found at Brazilian Caatinga and data on the biochemical composition of this plant are scarce. The present work describes the purification of P. elatior leaf lectin (PeLL) as well as the assessment of its antimicrobial activity and toxicity. PeLL, isolated by chromatography on a chitin column, had native liquid charge and subunit composition evaluated by electrophoresis. Hemagglutinating activity (HA) of PeLL was determined in the presence of carbohydrates or divalent cations, as well as after heating and incubation at different pH values. Changes in the lectin conformation were monitored by evaluating intrinsic tryptophan fluorescence and using the extrinsic probe bis-ANS. Antimicrobial activity was evaluated against Pectobacterium strains and Candida species. The minimal inhibitory (MIC), bactericidal (MBC), and fungicidal (MFC) concentrations were determined. Finally, PeLL was evaluated for in vitro hemolytic activity in human erythrocytes and in vivo acute toxicity in mice (5 and 10 mg/kg b.w. per os). PeLL (pI 5.4; 20 kDa) had its HA was inhibited by mannose, galactose, Ca2+, Mg2+, and Mn2+. PeLL HA was resistant to heating at 100 °C, although conformational changes were detected. PeLL was more active in the acidic pH range, in which no conformational changes were observed. The lectin presented MIC and MBC of 0.185 and 0.74 µg/mL for all Pectobacterium strains, respectively; MIC of 1.48 µg/mL for C. albicans, C. tropicalis, and C. krusei; MIC and MFC of 0.74 and 2.96 µg/mL for C. parapsilosis. No hemolytic activity or signs of acute toxicity were observed in the mice. In conclusion, a new, low-toxic, and thermostable lectin was isolated from P. elatior leaves, being the first plant compound to show antibacterial activity against Pectobacterium.


Assuntos
Anti-Infecciosos , Portulaca , Humanos , Animais , Camundongos , Lectinas , Anti-Infecciosos/toxicidade , Anti-Infecciosos/análise , Antibacterianos/toxicidade , Folhas de Planta/química , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia
20.
Eur J Orthop Surg Traumatol ; 33(3): 571-580, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36094673

RESUMO

INTRODUCTION: The standard treatment of anterior glenaoid fractures carrying > 20% of the glenoid fossa is open reduction and internal fixation (ORIF). In the herein study, we report our outcomes in a retrospective cohort of anterior and anteroinferior glenoid rim fractures using an accelerated postoperative rehabilitation protocol. A secondary aim is to describe the surgical steps for ORIF of anterior and anteroinferior glenoid rim fractures using the anterior axillary approach, describing the tricks, pearls, and pitfalls of this surgical technique. METHODS: A retrospective cohort of skeletally mature patients treated for an anterior glenoid rim fracture carrying > 20% of the glenoid fossa during a 10-year period were operated on using a vertical axillary incision, osteosynthesis with 2.0-mm cortical screws, and labral repair with small diameter metallic anchors and non-absorbable sutures. Rehabilitation began on the first postoperative day, including passive external rotation exercises and active-assisted flexion, adduction, and abduction exercises as tolerated. The exercises are performed with the patient sitting or lying down. Phase 1 is continued for 6-10 weeks until the patient regains painless, normal, or near-normal ROM. Usually by 10 weeks, the fracture and labrum are healed, so phase 2 rehabilitation begins with strengthening and ROM exercises. Radiologic and clinical outcomes, including active range of motion (ROM), glenohumeral stability, and visual analogue scale (VAS) were measured. RESULTS: About 33 patients (35 fractures) had complete medical records and pre- and post-operative imaging exams available for further analysis regarding the surgical protocol, with a mean of 4.8 years. The mean DASH questionnaire was 3.75 ± 9.0 and the mean CM score was 62.5 ± 0.1. Active flexion and internal rotation were recovered in all patients, while external rotation presented an average loss of 8° (p = 0.12) and abduction of 5° (p = 0.33). The mean VAS was 1.1 ± 0.8. No patient reported major or disabling symptoms, or great difficulty or inability to perform daily or recreational activities. No patient presented residual instability of the glenohumeral joint. CONCLUSION: In this retrospective cohort, ORIF using a vertical axillary incision, osteosynthesis with 2.0-mm screws, and labral repair with small diameter metallic anchors and non-absorbable sutures was a safe approach, with a minimal risk of complications and residual instability. The accelerated postoperative rehabilitation protocol, allowing immediate passive external rotation of the operated shoulder, resulted in a non-significant loss of ROM compared to the contralateral side. Therefore, we recommend this management strategy for anterior glenoid rim fractures in patients with unstable shoulder joint after traumatic glenohumeral dislocation. LEVEL OF EVIDENCE IV: Therapeutic Study (Surgical technique and Retrospective cohort).


Assuntos
Fraturas Ósseas , Instabilidade Articular , Luxação do Ombro , Articulação do Ombro , Humanos , Estudos Retrospectivos , Escápula/cirurgia , Fraturas Ósseas/cirurgia , Fraturas Ósseas/complicações , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Articulação do Ombro/cirurgia , Luxação do Ombro/cirurgia , Instabilidade Articular/etiologia , Amplitude de Movimento Articular , Artroscopia/métodos , Resultado do Tratamento
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