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8.
Front Bioeng Biotechnol ; 12: 1355950, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139296

RESUMO

The most recent progress in reconstructive therapy for the management of periodontitis and peri-implantitis bone defects has relied on the development of highly porous biodegradable bioaerogels for guided bone regeneration. The objective of this work was to evaluate in vitro the osteoinduction of periodontal-originating cells (human dental follicle mesenchymal cells, DFMSCs) promoted by a nano-hydroxyapatite/chitosan (nHAp/CS) bioaerogel, which was purified and sterilized by a sustainable technique (supercritical CO2). Moreover, the in vivo bone regeneration capacity of the nHAp/CS bioaerogel was preliminarily assessed as a proof-of-concept on a rat calvaria bone defect model. The quantification of DNA content of DFMSCs seeded upon nHAp/CS and CS scaffolds (control material) showed a significant increase from the 14th to the 21st day of culture. These results were corroborated through confocal laser scanning microscopy analysis (CLSM). Furthermore, the alkaline phosphatase (ALP) activity increased significantly on the 21st day, similarly for both materials. Moreover, the presence of nHAp promoted a significantly higher expression of osteogenic genes after 21 days when compared to CS scaffolds and control. CLSM images of 21 days of culture also showed an increased deposition of OPN over the nHAp/CS surface. The in vivo bone formation was assessed by microCT and histological analysis. The in vivo evaluation showed a significant increase in bone volume in the nHAp/CS test group when compared to CS and the empty control, as well as higher new bone formation and calcium deposition within the nHAp/CS structure. Overall, the present study showed that the nHAp/CS bioaerogel could offer a potential solution for periodontal and peri-implant bone regeneration treatments since the in vitro results demonstrated that it provided favorable conditions for DFMSC proliferation and osteogenic differentiation, while the in vivo outcomes confirmed that it promoted higher bone ingrowth.

9.
Braz J Microbiol ; 55(2): 1451-1463, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38656427

RESUMO

Antarctic temperature variations and long periods of freezing shaped the evolution of microorganisms with unique survival mechanisms. These resilient organisms exhibit several adaptations for life in extreme cold. In such ecosystems, microorganisms endure the absence of liquid water and exhibit resistance to freezing by producing water-binding molecules such as antifreeze proteins (AFP). AFPs modify the ice structure, lower the freezing point, and inhibit recrystallization. The objective of this study was to select and identify microorganisms isolated from different Antarctic ecosystems based on their resistance to temperatures below 0 °C. Furthermore, the study sought to characterize these microorganisms regarding their potential antifreeze adaptive mechanisms. Samples of soil, moss, permafrost, and marine sediment were collected on King George Island, located in the South Shetland archipelago, Antarctica. Bacteria and yeasts were isolated and subjected to freezing-resistance and ice recrystallization inhibition (IR) tests. A total of 215 microorganisms were isolated, out of which 118 were molecularly identified through molecular analysis using the 16S rRNA and ITS regions. Furthermore, our study identified 24 freezing-resistant isolates, including two yeasts and 22 bacteria. A total of 131 protein extracts were subjected to the IR test, revealing 14 isolates positive for AFP production. Finally, four isolates showed both freeze-resistance and IR activity (Arthrobacter sp. BGS04, Pseudomonas sp. BGS05, Cryobacterium sp. P64, and Acinetobacter sp. M1_25C). This study emphasizes the diversity of Antarctic microorganisms with the ability to tolerate freezing conditions. These microorganisms warrant further investigation to conduct a comprehensive analysis of their antifreeze capabilities, with the goal of exploring their potential for future biotechnological applications.


Assuntos
Proteínas Anticongelantes , Bactérias , Congelamento , Regiões Antárticas , Proteínas Anticongelantes/metabolismo , Proteínas Anticongelantes/química , Proteínas Anticongelantes/genética , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Ilhas , Filogenia , Leveduras/genética , Leveduras/classificação , Leveduras/isolamento & purificação , Leveduras/metabolismo , RNA Ribossômico 16S/genética , Ecossistema
10.
Braz J Biol ; 84: e273999, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451628

RESUMO

The production of seedlings of the passion fruit tree, usually, is sexual, and the seeds are not uniform in the seedling emergence, and soaking treatments of seeds can provide faster and more uniform germination. It was aimed to study the action of plant growth regulators and the mobilization of reserves in the stages of soaking of yellow passion fruit seeds. The seeds were soaked for five hours in solutions containing plant growth regulators, in a completely randomized design, in a factorial 8 x 4, with four replications. The first factor corresponds to eight plant growth regulators: T1 - distilled water (control); T2 - 6-benzylaminepurine ​​500 mg L-1; T3 - 4-(3-indolyl) butyric acid 500 mg L-1; T4 - gibberellic acid 500 mg L-1; T5 - spermine 250 mg L-1; T6 - spermine 750 mg L-1; T7 - spermidine 750 mg L-1; T8 - spermidine 1250 mg L-1; and the second factor, to the four soaking times: zero, four, 72 and 120 hours, corresponding, respectively, to the dry seed, and to phases I, II, and III of the imbibition curve. It was evaluated the biochemical composition of seeds (lipids, soluble sugars and starch). The seeds showed accumulation of lipids in phase III; the content of soluble sugars increased in phase I and decreased in phase II. The starch content increased until the phase II and decreased in phase III. Starch is the main reserve in the seeds and the main source of energy used in phase III; soaking the seeds in polyamines generates an accumulation of lipids in the seeds and soaking in plant growth regulators increases the burning of starch.


Assuntos
Passiflora , Reguladores de Crescimento de Plantas , Reguladores de Crescimento de Plantas/farmacologia , Frutas , Espermidina , Espermina , Ácido Butírico , Plântula , Amido , Açúcares
11.
Artigo em Inglês | MEDLINE | ID: mdl-38376470

RESUMO

Summary: Background. Bee venom allergy (BVA) can trigger local and systemic allergic reactions, including anaphylaxis. Recently, the molecular sensitization profile has gained importance in the reaction's stratification and venom immunotherapy (VIT). Methods. Retrospective analysis of patients with hypersensitivity to BVA, confirmed by specific sIgE to Apis mellifera ≥0.35 kU/L and/or positive skin tests to bee venom commercial extract, evaluated in specialized consultation. Demographic, clinical, and laboratory data (including molecular Api m 1, 4, and 10) were analyzed, looking for risk factors associated with the severity of the index reaction and reactions during VIT. Results. 93 patients were included (55.9% male; median age of 46 years), 57.3% with atopic comorbidities, and 23.4% with cardiovascular comorbidities. The median specific IgE to Apis mellifera was 6.7 kU/L (IQR 1.0-20.3) kU/L. Regarding the molecular profile, the median IgE to Api m 1 was 0.5 kU/L (57.5% positive out of all measurements); Api m 4 - 0.01 kU/L (11.9% positive), and Api m 10 - 0.3 kU/L (50.0% positive). No patient was monosensitized to Api m 4. The median age of the most severe sting reaction was 36 (IQR 26-48) years, with a median severity (Müeller scale) of 3 (IQR 2-3). Forty-seven patients (50.5%) underwent VIT, with 35.6% of reactions recorded. Allergic reactions during VIT were recorded in 35.6% of cases. The severity of the index reaction correlated positively with older ages (p=0.040; r=0.249), in contrast to monosensitization to Api m 1, which was an independent predictor of milder reactions (p=0.015). Sensitization to Api m 10 was associated with a higher likelihood of reactions during VIT (p=0.038) but potentially less systemic reactions at re-stings (p=0.097). Conclusions. Molecular sensitization profile appears to be relevant not only to the severity of index reactions but also during VIT. Studies of a large cohort of patients with molecular profiles are essential to validate these results and improve the clinical and therapeutic approach to BVA.

12.
Braz J Biol ; 83: e277437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422256

RESUMO

The use of residues from coffee production to obtain biochar is a sustainable approach, which aims to minimize the environmental impact of these materials. In this study, the effect of adding coffee straw biochar on the physiological quality of lettuce and sorghum seeds was investigated. Thus, the objective of this work was to study the effect of adding different concentrations of coffee biochar in the substrate composition on the physiological quality of lettuce (Lactuca sativa) and sorghum (Sorghum bicolor) seeds. The experimental design used was completely randomized, with five concentrations of biochar (0; 7.5; 15; 30 and 60%), conducted with four replications of 25 seeds. The use of biochar in the concentrations studied does not provide an increase in the average germination percentage and vigor of lettuce and sorghum seeds. The increase in the concentration of biochar caused less seed vigor, suggesting a toxic effect. For seed germination, there was no significant difference between lettuce and sorghum species, regardless of treatment. For the germination speed index, sorghum seeds have higher means, except for the treatment with the addition of 15% coffee straw biochar. Lettuce seeds have higher shoot length averages, except for treatment with 100% commercial substrate. The sorghum seeds have higher mean root length and dry mass than lettuce, regardless of the treatment.


Assuntos
Carvão Vegetal , Germinação , Sorghum , Café , Grão Comestível , Lactuca , Sementes/fisiologia
13.
PLoS One ; 19(1): e0285649, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38198443

RESUMO

On the edge of causing the sixth big mass extinction event, the development of positive attitudes towards the conservation of intraspecific diversity from early ages is essential to overcome the biodiversity crisis we currently face. However, there is no information available on elementary school students' attitudes toward intraspecific diversity conservation nor is there a framework available to perform such analysis. For this study we designed, implemented, and evaluated an educational activity planned for third graders (8 to 13 years old) to explore the intraspecific diversity of vegetables and promote healthy eating habits. Additionally, a framework was developed to evaluate students' attitudes towards intraspecific diversity conservation and applied to semi-structured interviews conducted with students before and after engaging in the educational activity. In this paper we present a reliable framework, developed aligned with the ABC model of attitudes, based on literature, and adapted to elementary school students' responses, to evaluate students' attitudes toward intraspecific diversity. Our results show that, before the educational activity, most students choose a non-biodiverse option, justifying this choice with the affective component of attitudes: mostly emotional factors but also aesthetic and social/cultural factors. After the educational activity, we observed a significant increase in the frequency of students that choose the biodiverse option and that justified it with the cognitive component of attitudes: mainly with biology and health knowledge factors, but also with economic and ethical knowledge factors. Our findings support the positive impact of educational activities that explore vegetable varieties on students' attitudes toward intraspecific diversity conservation. This activity may also be used to foster education for sustainability and address socioscientific issues aligned with diverse sustainable development goals.


Assuntos
Otimismo , Estudantes , Criança , Humanos , Adolescente , Escolaridade , Emoções , Biodiversidade , Verduras
16.
Braz J Biol ; 83: e274888, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38055577

RESUMO

Ateleia glazioveana Baill. is a pioneer, rustic and can be used for forest recovery. This work aimed to study the process of physiological maturation of this species. The research was carried out in the city of Alegre - ES, the trees were identified in the floral anthesis and accompanied during the filling of the fruits and development of the seeds until the complete maturation. The fruits were harvested at the following stages 7, 14, 21, 28, 35 and 42 days after anthesis, and characterized according to: morphometry, moisture, fresh and dry mass of fruits and seeds, germination, germination speed index, shoot and root length and dry mass of seedlings. The regression equations were adjusted for the main characteristics analyzed as a function of the harvest period. The point of physiological maturity of timbó occurred at 42 days after anthesis.


Assuntos
Fabaceae , Sementes , Germinação/fisiologia , Plântula , Frutas
17.
Braz J Biol ; 83: e275338, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970903

RESUMO

Simultaneous analysis studies of several agronomic traits in cultivated plants make it possible to identify phenotypic and genotypic differences due to environmental variations, such as altitude. Therefore, the objective was to evaluate, through multivariate analysis of agronomic, physicochemical and physiological characters, passion fruit hybrids cultivated in different environments. The hybrids used were Gigante Amarelo, Rubi do Cerrado and Sol do Cerrado, cultivated in the southern region of Espírito Santo in four municipalities/environments: Marataízes (41 m), Jerônimo Monteiro (104 m), Alegre (711 m), and Ibitirama (1016 m). The agronomic characters of the plants, the physical-chemical characteristics of the fruits and the physical, biochemical and physiological qualities of the seeds were analyzed. The Singh method was used to determine the most important differentiating characters between hybrids growing in different environments. Based on these characters, a dissimilarity matrix was generated and a principal coordinate analysis was performed. It was observed that the pulp yield was influenced by altitude. The three hybrids showed greater performance in terms of agronomic characters at altitude (41 m) than at altitude (104 m). The Sol do Cerrado hybrid showed high performance in the physical-chemical characteristics of the fruits at altitude (104 m).


Assuntos
Frutas , Passiflora , Frutas/genética , Passiflora/genética , Sementes , Agricultura , Análise Multivariada
19.
Immunol Lett ; 262: 7-17, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37634711

RESUMO

This study was designed to characterize mice bone marrow (BM) and bone marrow-derived dendritic cells (BMDC) and to compare the surface markers expression and inflammatory cytokine liberation in response to LPS and Bothrops jararacussu venom (BjV) stimulation. Typical morphology was observed in BM and BMDCs from the 4th up to the 8th day of culture using recombinant mouse GM-CSF and IL-4. A high basal level of MHC-II, CD1d, CD83, CD11c, CD80, and low CD86 was expressed by BM cells. After stimulation with GM-CSF/IL-4 for BMDCs differentiation, the BM cells differentiated into BMDCs presented MHC-II, CD1d, CD83, CD11c, CD86, and CD80 expression on the 4th - 8th day accompanied with high levels of TNF-α liberated. The difference between the surface markers' expression was observed in this time course in which CD1d, CD11c, and CD80 remained in high levels of expression, while MHC-II and CD83 showed moderate expression during the differentiation period. Also, cytokines liberation was monitored over the period of the BMDCs culture, and on the 6th day, low levels of IL-6 and IL-1ß were found, while high levels of TNF-α on the 4th and 8th days, both of which contributed to the maturity of the BMDCs. Maturation of DCs with LPS showed significant upregulation of surface markers (MHC-II, CD1d, CD83, CD86, CD80) and pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α) liberation. On the other hand, BjV induced a decrease in CD1d, CD11c, CD83, and CD86 expression in mature BMDCs which was not observed when LPS was used to stimulate BMDCs which probably induces impairment in T-cell activation.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos , Fator de Necrose Tumoral alfa , Animais , Camundongos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Medula Óssea , Interleucina-4 , Interleucina-6 , Lipopolissacarídeos , Venenos de Serpentes , Citocinas , Células Dendríticas
20.
Public Health Pract (Oxf) ; 6: 100419, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37608848

RESUMO

Objective: Assess the perceived protection afforded by a range of COVID-19 vaccines in immune-mediated inflammatory diseases patients previously vaccinated against SARS-CoV-2. Study design: Survey. Methods: On-line cross-sectional survey aimed at evaluating the perceived protection (and its determinants) afforded by a range of COVID-19 vaccines among immune-mediated inflammatory diseases previously vaccinated for COVID-19. Results: Out of 493 eligible respondents who lived in Brazil, 397 (80.5%) were confident that their primary vaccination series would protect them against severe COVID-19. In multivariate analysis, only overlapping immune-mediated inflammatory diseases remained (negatively) associated with the perception of protection. Conclusions: No influence was found between COVID-19 vaccine types and the perception of protection after initial vaccinations.

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