Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 198
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Naturwissenschaften ; 111(5): 44, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136793

RESUMO

Galls are plant neoformations induced by specialized parasites. Since gall inducers rely on reactive plant sites for gall development, variations in abiotic factors that affect plant phenology are expected to impact the life cycle of gall inducers. To test the hypothesis that different light conditions affect both host plant and gall inducer life cycles, we studied the system Eugenia uniflora (Myrtaceae) - Clinodiplosis profusa (Cecidomyiidae), comparing plants occurring in sunny and shaded environments. We mapped phenological differences among individuals of E. uniflora occurring in the two environments and related them to the influence of luminosity on the life cycle of the gall inducer. Shade plants showed lower intensity of leaf sprouting throughout the year compared to sun-exposed plants, especially during the rainy season. Young and mature galls are synchronized with the peak of leaf sprouting at the beginning of the rainy season, lasting longer in sun-exposed plants - approximately two months longer compared to shade plants. The greater light intensity positively impacts the formation and growth of leaves and galls, with an extended period available for their induction and growth. Thus, light is an important factor for the development of gallers, considering that variations in luminosity influenced not only the phenology of the host plant, but also determined the life cycle of gall inducers. Furthermore, changes in plant-environment interactions are expected to affect the life cycle and richness of other host plant-gall inducer systems.


Assuntos
Eugenia , Luz Solar , Eugenia/fisiologia , Animais , Tumores de Planta/parasitologia , Luz , Folhas de Planta/parasitologia , Folhas de Planta/fisiologia , Estações do Ano , Interações Hospedeiro-Parasita/fisiologia , Estágios do Ciclo de Vida/fisiologia
2.
J Mater Sci Mater Med ; 35(1): 12, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315254

RESUMO

The development of wound dressings from biomaterials has been the subject of research due to their unique structural and functional characteristics. Proteins from animal origin, such as collagen and chitosan, act as promising materials for applications in injuries and chronic wounds, functioning as a repairing agent. This study aims to evaluate in vitro effects of scaffolds with different formulations containing bioactive compounds such as collagen, chitosan, N-acetylcysteine (NAC) and ε-poly-lysine (ε-PL). We manufactured a scaffold made of a collagen hydrogel bioconjugated with chitosan by crosslinking and addition of NAC and ε-PL. Cell viability was verified by resazurin and live/dead assays and the ultrastructure of biomaterials was evaluated by SEM. Antimicrobial sensitivity was assessed by antibiogram. The healing potential of the biomaterial was evaluated in vivo, in a model of healing of excisional wounds in mice. On the 7th day after the injury, the wounds and surrounding skin were processed for evaluation of biochemical and histological parameters associated with the inflammatory process. The results showed great cell viability and increase in porosity after crosslinking while antimicrobial action was observed in scaffolds containing NAC and ε-PL. Chitosan scaffolds bioconjugated with NAC/ε-PL showed improvement in tissue healing, with reduced lesion size and reduced inflammation. It is concluded that scaffolds crosslinked with chitosan-NAC-ε-PL have the desirable characteristics for tissue repair at low cost and could be considered promising biomaterials in the practice of regenerative medicine.


Assuntos
Acetilcisteína , Anti-Infecciosos , Quitosana , Animais , Camundongos , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/química , Quitosana/química , Colágeno/química , Alicerces Teciduais/química , Cicatrização , Polilisina/química
3.
BMC Nurs ; 23(1): 376, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834990

RESUMO

BACKGROUND: The literature review notes that people in need of care from Rehabilitation Programs do not always see their continuity ensured. OBJECTIVE: This study aim to analyze the perspective of Specialists Nurse in Rehabilitation Nursing in relation to the organization and specialized intervention of transitional care for older people in need of rehabilitation programs. METHODS: This is a qualitative study within the interpretivist paradigm. A focus group with 8 nurses and 13 interviews with Portuguese nurses were carried out between April 2022 and February 2023. Content analysis was carried out. RESULTS: The triangulation of the data made it possible to identify 3 categories: Coordination of a transitional care program; Empowering the person to self-manage the transitional care process and Empowering the Informal Caregiver. CONCLUSIONS: It is imperative to promote the coordination of transitional care, increase the functional capacity of the person and empower the informal caregiver.

4.
Anal Chem ; 95(28): 10634-10643, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37347237

RESUMO

A simple fabrication method to make electrochemical sensors is reported. The electrodes were fabricated with a commercial filament based on polylactic acid and carbon black (PLA/CB). They were engineered with a three-dimensional (3D) printing pen and poly(methyl methacrylate) template. The optimization parameters included the thickness and diameters of the electrodes. The electrode diameter was restricted by the 3D printing pen's nozzle dimension, and larger diameters generated small cracks on the electrode surface, compromising their analytical signal. The electrode thickness can increase the electrical resistance, affecting their electrochemical response. The fabrication showed reproducibility (RSD = 4%). The electrode surface was easily renewed by sanding the electrodes, making them reusable. Additionally, the proposed sensor provided comparable electrochemical responses over traditional glassy carbon electrodes. Moreover, no (electro)chemical surface treatment was required for sensing applications due to the compromise between the thickness and diameters of the electrodes, effectively translating the filaments' electrical properties to resulting materials. The electrodes' analytical performance was shown for organic and inorganic species, including paraquat, Pb2+, and caffeic acid. As proof of concept, the analytical applicability was demonstrated for total polyphenolic quantification in tea samples. Therefore, this work provides an alternative to fabricating miniaturized electrodes, bringing valuable insights into PLA/CB 3D-printed sensors and opening possibilities for designing electrode arrays. Moreover, the proposed electrodes are promising platforms for paper-based microfluidic systems.

5.
Crit Rev Food Sci Nutr ; 63(28): 9217-9232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35467994

RESUMO

Ionic liquids (IL) are innovative alternative solvents to recover bioactive compounds from plant-based sources to replace toxic volatile organic solvents (VOS). ILs are tailored-made solvents with chemical and thermal stabilities, nonvolatile and noninflammable. Although ILs are versatile, cost-effective, and sustainable solutions, the European Commission (EC) has no current regulation to approve extracts obtained with ILs to be applied in foods. Herein, this paper aims to assess the overview of ILs, regulamentation, applications, and its toxic effects, to be used as solvents for extract different bioactive compounds. Studies have suggested novel applications for ILs, such as 1-butyl-3-methylimidazolium bromide, 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium tetrafluoroborate and others, to obtain bioactive compounds, for instance phenolic compounds, lignans, alkaloids, carotenoids, polysaccharides, using modern approaches as ultrasound and microwave-assisted extraction. New IL methods increase the efficiency of recovering target compounds and decrease the extraction time and VOS consumption regarding the traditional techniques. Furthermore, to promote the large-scale use of IL in foods, it is essential to investigate individually the toxicity of each IL used in the extraction processes, aiming to obtain a GRAS stamp, due to the currently lack of regulamentation.


Assuntos
Líquidos Iônicos , Solventes , Líquidos Iônicos/farmacologia , Solventes/toxicidade
6.
Naturwissenschaften ; 110(5): 49, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737319

RESUMO

Leaf-galling Eriophyidae (Acarina) may promote simple or complex alterations in the organs of their host plants, such as an increase in indumentum density or the reorganization of epidermis and ground system tissue patterns. To test if hairy galls of Eriophyidae on Avicennia schaueriana (Acanthaceae) are related to complex changes, leaf galls in distinct developmental phases were compared to non-galled leaves using anatomical, histochemical, and histometric analyses. Quantitative comparisons of preferential gall induction sites and gall area according to distinct leaf portions were made to evaluate if the impacts of gall formation can be related to the distinct potentialities of leaf microsites. The apical portion of the leaves and leaf margins were the sites with the highest occurrence of galls, but no relationship was detected between gall area and induction site. The gall anatomy revealed that epidermal features are influenced the most with the development of abnormal stomata and projected or sunken salt glands. The most striking change is the neoformation of elongated filiform trichomes on the abaxial surface (where the mites occur) that accumulate reducing sugars and proteins. The filiform trichomes may protect the inducers against abiotic stressors and enemies, and the primary metabolites that accumulate are important foods for mites. The mesophyll has simple alterations, only in the spongy parenchyma. Complex alterations occur only in abaxial epidermal cells close to feeding sites of the inducer. The number of inducers per gall seems to be the most important influence on gall size, since gall area is not related to the position in the leaves.


Assuntos
Avicennia , Animais , Epiderme , Folhas de Planta
7.
Mol Divers ; 27(1): 281-297, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35441971

RESUMO

Botrytis cinerea, Rhizoctonia solani and Hemileia vastatrix are three species of phytopathogenic fungi behind major crop losses worldwide. These have been selected as target models for testing the fungicide potential of a series of bis(ylidene) cyclohexanones. Although some compounds of this chemical class are known to have inhibitory activity against human pathogens, they have never been explored for the control of phytopathogens until now. In the present work, bis(ylidene) cyclohexanones were synthesized through simple, fast and low-cost base- or acid-catalyzed aldol condensation reaction and tested in vitro against B. cinerea, R. solani and H. vastatrix. bis(pyridylmethylene) cyclohexanones showed the highest activity against the target fungi. When tested at 200 nmol per mycelial plug against R. solani., these compounds completely inhibited the mycelial growth, and the most active bis(pyridylmethylene) cyclohexanone compound had an IC50 of 155.5 nmol plug-1. Additionally, bis(pyridylmethylene) cyclohexanones completely inhibited urediniospore germination of H. vastatrix, at 125 µmol L-1. The most active bis(pyridylmethylene) cyclohexanone had an IC50 value of 4.8 µmol L-1, which was estimated as approximately 2.6 times lower than that found for the copper oxychloride-based fungicide, used as control. Additionally, these substances had a low cytotoxicity against the mammalian Vero cell line. Finally, in silico calculations indicated that these compounds present physicochemical parameters regarded as suitable for agrochemicals. Bis(ylidene) cyclohexanones may constitute promising candidates for the development of novel antifungal agents for the control of relevant fungal diseases in agriculture.


Assuntos
Antifúngicos , Fungicidas Industriais , Humanos , Cicloexanonas , Doenças das Plantas/microbiologia , Fungos , Plantas
8.
Retina ; 43(10): 1680-1690, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37531971

RESUMO

PURPOSE: To evaluate the parafoveal macular microvasculature and the macular function in patients with retinal vasculitis associated with Behçet's uveitis. METHODS: In 14 patients with inactive Behçet's uveitis and 26 control individuals (13 with nonocular Behçet's syndrome and 13 healthy subjects), we analyzed the retinal nerve fiber layer, ganglion cell layer, full retinal thickness, foveal avascular zone area and sectorial parafoveal vascular density in the superficial vascular plexus, intermediate capillary plexus, and deep capillary plexus using SPECTRALIS optical coherence tomography (OCT) 2 and OCT angiography. Macular sensitivity was analyzed using an MP-3 microperimeter. RESULTS: Eighteen eyes (78%) had a best-corrected visual acuity ≥ 20/25. Significant differences were found in Behçet's uveitis in comparison with the controls on the OCT and OCT angiography: 14.8%, 22.4%, and 14.9% ganglion cell layer thinning in the global, nasal, and inferior sectors, respectively; 6%, 13.2%, and 7.5% full retinal thickness thinning in the superior, nasal, and inferior sectors; and 16.8%, 14.9%, 23.6%, 15.8%, and 12.6% mean deep capillary plexus density reduction in the global, superior, nasal, inferior, and temporal sectors. Microperimetry data demonstrated significant mean reductions of 21% and 23.6% in central and average macular sensitivities and 28.8%, 40.4%, 27.7%, and 24.2% in the superior, nasal, inferior, and temporal sectors, respectively. Outer plexiform layer elevations were observed in Behçet's uveitis (69.6%). CONCLUSION: Behçet's uveitis presented structural and functional macular damage despite good best-corrected visual acuity, mainly affecting the nasal sector and the deep capillary plexus. On OCT and OCT angiography, quantitative and qualitative changes can be valuable biomarkers of ocular involvement in Behçet's syndrome.


Assuntos
Síndrome de Behçet , Uveíte , Humanos , Síndrome de Behçet/diagnóstico , Tomografia de Coerência Óptica/métodos , Angiofluoresceinografia/métodos , Vasos Retinianos , Testes de Campo Visual , Retina , Uveíte/diagnóstico , Uveíte/etiologia , Biomarcadores
9.
Sensors (Basel) ; 23(14)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37514611

RESUMO

Accurate localization is a critical task in underwater navigation. Typical localization methods use a set of acoustic sensors and beacons to estimate relative position, whose geometric configuration has a significant impact on the localization accuracy. Although there is much effort in the literature to define optimal 2D or 3D sensor placement, the optimal sensor placement in irregular and constrained 3D surfaces, such as autonomous underwater vehicles (AUVs) or other structures, is not exploited for improving localization. Additionally, most applications using AUVs employ commercial acoustic modems or compact arrays, therefore the optimization of the placement of spatially independent sensors is not a considered issue. This article tackles acoustic sensor placement optimization in irregular and constrained 3D surfaces, for inverted ultra-short baseline (USBL) approaches, to improve localization accuracy. The implemented multi-objective memetic algorithm combines an evaluation of the geometric sensor's configuration, using the Cramer-Rao Lower Bound (CRLB), with the incidence angle of the received signal. A case study is presented over a simulated homing and docking scenario to demonstrate the proposed optimization algorithm.

10.
J Environ Manage ; 337: 117665, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36940604

RESUMO

The homogenization of fire regimes in a landscape may imply a temporal reduction in the availability of resources, such as flowers and fruits, which affect the fauna, as well as ecosystem services. We hypothesized that maintaining mosaic burning regimes, and thereby pyrodiversity, can diversify phenological patterns, ensuring year-round availability of flowers and fruits. Here we monitored open grassy tropical savanna phenology under different historical fire frequencies and fire seasons in a highly heterogeneous landscape in an Indigenous Territory in Brazil. We evaluated phenological patterns of tree and non-tree plants through monthly surveys over three years. These two life forms responded differently to climate and photoperiod variables and to fire. Different fire regimes led to a continuous availability of flowers and fruits, due to the complementarity between tree and non-tree phenologies. Late-season fires are supposed to be more devastating, but we did not detect a significant reduction in flower and fruit production, especially under moderate fire frequency. However, late burning in patches under high frequency resulted in a low availability of ripe fruits in trees. The fruiting of non-tree plants in patches under low fire frequency and early burning ensure ripe fruit, when there are practically no trees fruiting in the entire landscape. We conclude that maintaining a seasonal fire mosaic should be prioritized over historical fire regimes, which lead to homogenization. Fire management is best conducted between the end of the rainy season and the beginning of the dry season, when the risk of burning fertile plants is lower.


Assuntos
Ecossistema , Incêndios , Frutas , Pradaria , Reprodução , Flores
11.
Inflammopharmacology ; 31(3): 1539-1549, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37022573

RESUMO

Several species of the genus Ocotea are used in traditional medicine due to their anti-inflammatory and analgesic properties. In this work we sought to investigate the effects of biseugenol, the main component of the hexane extract from the leaves of Ocotea cymbarum (Lauraceae), during a chronic inflammatory process induced by polyester-polyurethane sponge in mice. In addition to the inflammatory component, sponge discs also allowed us to evaluate parameters associated with the formation of new blood vessels and the deposition and organization of the extracellular matrix, processes that are related to the chronification of the inflammatory response. Daily treatment with biseugenol (0.1, 1 or 10 µg in 10 µl of 0.5% DMSO) inhibited the synthesis of inflammatory cytokines (TNF-α, CXCL-1 and CCL2) and the neutrophil and macrophage infiltrate into to the implants, indirectly evaluated by the activity of myeloperoxidase and N-acetyl-ß-D-glycosaminidase enzymes, respectively. In implants treated with biseugenol, we observed a reduction in angiogenesis, assessed through histological quantification of mean number of blood vessels, the levels of the pro-angiogenic cytokines FGF and VEGF and the activity of metalloproteinases. Except for VEGF levels, all mentioned parameters showed significant reductions after treatment with biseugenol. Finally, the administration of the compound also reduced TGF-ß1 levels, collagen synthesis and deposition, in addition to modifying the organization of the newly formed matrix, presenting a potential anti-fibrotic effect. Therefore, our results demonstrate the potential therapeutic use of biseugenol for the treatment of a series of pathological conditions, where parameters associated with inflammation, angiogenesis and fibrogenesis are deregulated.


Assuntos
Lauraceae , Ocotea , Animais , Camundongos , Fator A de Crescimento do Endotélio Vascular , Neovascularização Patológica/tratamento farmacológico , Inflamação/tratamento farmacológico , Colágeno , Citocinas
12.
Molecules ; 28(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37446907

RESUMO

The present study aims to explore the anti-inflammatory potential activity of the hexane extract from branches (HEB) of Endlicheria paniculata (Lauraceae) and its main compound, methyldehydrodieugenol B, in the inflammatory response induced by a murine implant sponge model. HPLC-ESI/MS analysis of HEB led to the identification of six chemically related neolignans, with methyldehydrodieugenol B as the main compound. An in silico analysis of the pharmacokinetic parameters of the identified compounds suggested moderate solubility but good absorption and biodistribution in vivo. Thus, the treatment of mice with HEB using in vivo assays indicated that HEB promoted pro-inflammatory, antiangiogenic, and antifibrogenic effects, whereas treatment with methyldehydrodieugenol B caused anti-inflammatory, antifibrogenic, and antiangiogenic effects. The obtained results shown the therapeutic potential of HEB and methyldehydrodieugenol B in the treatment of pathologies associated with inflammation and angiogenesis, including chronic wounds.


Assuntos
Hexanos , Lauraceae , Camundongos , Animais , Distribuição Tecidual , Extratos Vegetais/farmacologia , Inflamação/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Lauraceae/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos
13.
Trop Anim Health Prod ; 55(3): 225, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37225948

RESUMO

Bovine brucellosis, mainly caused by Brucella abortus, is a worldwide distribution anthropozoonosis that causes great economic losses. In 2001, Brazil launched the National Program for the Control and Eradication of Brucellosis and Tuberculosis (PNCEBT). Contemporaneously, a great effort to characterize the epidemiology of the disease in Brazilian states was started. In the state of Rondônia, a first epidemiological study was carried out in 2004, revealing a prevalence of 35.2% of infected herds and 6.22% of seropositive females. In 2014, after a successful heifer vaccination program with strain 19 (S19), a second study detected a reduction in the prevalence of infected herds to 12.3% and of seropositive females to 1.9%. The present study aimed to quantify and compare the costs and benefits related to the control of bovine brucellosis in the state through an accounting analysis. Vaccinating heifers and performing serological tests to move animals were computed as private costs. The expenditures of the state official veterinary service for brucellosis control were considered public cost. The considered benefits of lowering prevalence were decreased cow replacement, decreased abortions, decreased perinatal and cow mortality, and increased milk production. Considering private and public costs, the net present value (NPV) was estimated at US$ 18.3 million, the internal rate of return (IRR) was calculated at 23%, and the benefit-cost ratio (BCR) was 1.7. When considering only the private costs, the NPV was US$34.9 million, the IRR was 49%, and the BCR was 3.0, meaning that the bovine producer had a return of 3 for each unit of currency invested. The results showed that the bovine brucellosis control measures implemented in the state of Rondônia, which had as its main strategy the vaccination of heifers with S19, produced highly advantageous economic results. The state should continue with its vaccination program, stimulating the use of the RB51 vaccine in addition to S19, to achieve further reductions in prevalence at low cost.


Assuntos
Brucelose Bovina , Brucelose , Doenças dos Bovinos , Gravidez , Animais , Bovinos , Feminino , Brasil/epidemiologia , Brucelose Bovina/epidemiologia , Brucelose Bovina/prevenção & controle , Brucella abortus , Brucelose/epidemiologia , Brucelose/prevenção & controle , Brucelose/veterinária , Vacinação/veterinária
14.
Mod Rheumatol ; 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37489771

RESUMO

OBJECTIVE: This study reported a family with most members affected by Czech dysplasia. We examined the patients' clinical, laboratory, and imaging characteristics and evaluated their functional capacity using the Stanford Health Assessment Questionnaire-Disability Index. METHODS: The method used was case series description and literature review. RESULTS: This study showed that the pathogenic variant c.823C>T in the COL2A1 gene, which is a characteristic of Czech dysplasia, was found in 12 Brazilian individuals. Half of the patients in this family met the criteria for rheumatoid arthritis (RA) based on the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria. Patients had arthritis in their hand joints, synovitis detected by ultrasound, and alterations in inflammatory tests. The Stanford Health Assessment Questionnaire-Disability Index assessment revealed that all patients exhibited moderate-to-severe functional disability. What distinguish Czech dysplasia from RA are an autosomal dominant inheritance pattern, platyspondyly, sensorineural hearing loss, and shortening of the metatarsal bones. CONCLUSIONS: It is important to consider Czech dysplasia as a potential differential diagnosis for RA. This autosomal dominant skeletal dysplasia is associated with normal height, short metatarsals, platyspondyly, hearing loss, enlarged epiphyses, and precocious osteoarthritis. Inflammatory findings such as arthritis, synovitis, and alteration of inflammatory markers may also be present in individuals with Czech dysplasia.

15.
Biotechnol Bioeng ; 119(2): 376-387, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34786710

RESUMO

Cis,cis-muconic acid (CCM) is a promising polymer building block. CCM can be made by whole-cell bioconversion of lignin hydrolysates or de novo biosynthesis from sugar feedstocks using engineered microorganisms. At present, however, there is no established process for large-scale CCM production. In this study, we developed an integrated process for manufacturing CCM from glucose by yeast fermentation. We systematically engineered the CCM-producing Saccharomyces cerevisiae strain by rewiring the shikimate pathway flux and enhancing phosphoenolpyruvate supply. The engineered strain ST10209 accumulated less biomass but produced 1.4 g/L CCM (70 mg CCM per g glucose) in microplate assay, 71% more than the previously engineered strain ST8943. The strain ST10209 produced 22.5 g/L CCM in a 2 L fermenter with a productivity of 0.19 g/L/h, compared to 0.14 g/L/h achieved by ST8943 in our previous report under the same fermentation conditions. The fermentation process was demonstrated at pilot scale in 10 and 50 L steel tanks. In 10 L fermenter, ST10209 produced 20.8 g/L CCM with a CCM yield of 0.1 g/g glucose and a productivity of 0.21 g/L/h, representing the highest to-date CCM yield and productivity. We developed a CCM recovery and purification process by treating the fermentation broth with activated carbon at low pH and low temperature, achieving an overall CCM recovery yield of 66.3% and 95.4% purity. In summary, we report an integrated CCM production process employing engineered S. cerevisiae yeast.


Assuntos
Engenharia Metabólica/métodos , Saccharomyces cerevisiae , Ácido Sórbico/análogos & derivados , Fermentação , Glucose , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Ácido Sórbico/química , Ácido Sórbico/isolamento & purificação , Ácido Sórbico/metabolismo
16.
Am J Bot ; 109(2): 209-225, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34730229

RESUMO

PREMISE: Gall-inducing organisms change the development of their host plant organs, resulting in ontogenetic patterns not observed in the non-galled plants. Distinct taxa induce galls on Schinus spp., manipulating meristematic patterns in the host plant in distinct ways. Here we report ontogenetic novelties induced in the lateral buds of S. engleri by Eucecidoses minutanus, a Cecidosidae, whose galls have been poorly understood. METHODS: The anatomy, histochemistry, and histometry of galls in distinct phases of development, non-galled buds, and stems of Schinus engleri were analyzed in parallel with the instars of E. minutanus to detail the morphogenetic changes in the host with each larval stage. RESULTS: Ontogenetic phases of the galls were intricately associated with larval development. First and second-instar larvae induced pericycle and pith cells to dedifferentiate into the gall inner meristem, where hyperplasia and cell hypertrophy characterized the growth and development phase of the gall. The innermost layers were lipid-rich nutritive cells that lined the larval chamber. Additional vascular bundle rows were produced in young galls. Third and fourth instar-larvae were associated with the gall maturation phase: centripetal lignification of the outer parenchyma cell layers, epidermal stratification, and activation of a cambium-like meristem (CLM). The CLM activity resulted in new layers of nutritive cells that differentiated inward as the first layers of nutritive cells were consumed by E. minutanus larvae, and, also, in more parenchyma cell layers that formed outward. All tissues between the innermost layer of nutritive tissue that surround the gall chamber and the outermost layer of the dermal system that externally covers the gall form the gall wall, and increased in thickness until the end of gall maturation. CONCLUSIONS: E. minutanus induces a structurally complex globoid stem gall, modifying all host plant tissues and stimulating a novel meristematic pattern in S. engleri. The gall developmental stages are each related to specific gall-inducing instars, as gall development progresses according to the development of E. minutanus.


Assuntos
Anacardiaceae , Animais , Larva , Meristema , Plantas
17.
An Acad Bras Cienc ; 94(2): e20210230, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830083

RESUMO

Wounds treated with TiO2 nanoparticles (TiO2-NPs) show an improvement in healing time. However, little is known about the parameters that can contribute to this result. On the other hand, the treatment of wounds with polyphenols is widely known. These compounds are found in the peel of Annona crassiflora fruit and have antioxidant, analgesic and anti-inflammatory properties. In this study, we evaluated the healing effect of TiO2 nanocrystals (TiO2-NCs), polyphenolic fractions obtained from ethanolic extract of A. crassiflora fruit peel (PFAC) and mix (PFAC + TiO2-NCs) on the parameters of wound closure, inflammation, collagen deposition, metalloproteinase activity (MMPs) and angiogenesis. TiO2-NCs and PFAC have activity for wound healing, showed anti-inflammatory action and a shorter wound closure time. These treatments also contributed to increased collagen deposition, while only treatment with TiO2-NCs increased MMP-2 activity, parameters essential for the migration of keratinocytes and for complete restoration of the injured tissue. The combination of PFAC + TiO2-NCs reduced the effectiveness of individual treatments by intensifying the inflammatory process, in addition to delaying wound closure. We conclude that the interaction between the hydroxyl groups of PFAC polyphenols with TiO2-NCs may have contributed to difference in the healing activity of skin wounds.


Assuntos
Annona , Nanopartículas , Annona/química , Anti-Inflamatórios/farmacologia , Colágeno , Nanopartículas/química , Polifenóis/farmacologia , Titânio , Cicatrização
18.
Plant Dis ; 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35971261

RESUMO

Hop - Humulus lupulus (Cannabaceae) - is an important and ancient, herbaceous, temperate, perennial crop. It is a vine which, although having other uses, is cultivated predominantly for the brewing industry (Laws 2013). Cultivation of hops in Brazil is relatively new and has increased in the last twenty years. There is only one published record of a fungal disease affecting hop in Brazil - powdery mildew (Fagherazzi et al 2021). In January 2021, leaf spots appeared on all eight hops plants ithe collection maintained in the Infectarium, a disease demonstration garden on the campus of the Universidade Federal de Viçosa (UFV), Viçosa, Minas Gerais, Brazil (https://www.infectario.ufv.br/). Symptoms were small, sub-circular to irregular spots, up to 5 mm, with a whitish to grayish center, surrounded by a dark brown necrotic margin, followed by a narrow yellowish outer margin. Older lesions became larger, grayish-brown, coalesced leading to extensive necrosis and stem dieback. A sample was collected, dried in a plant press, and deposited in the Herbarium of UFV (Acc. No VIC 47534). A dematiaceous fungus was found sporulating in the center of the lesions, when examined with a dissecting microscope. Fungal structures were scraped with a scalpel, mounted in lactoglycerol and observed with a light microscope (Olympus BX51). A pure culture was obtained after conidia were transferred onto PDA plates with a sterile fine-pointed needle. A representative isolate was deposited in the culture collection of the UFV (COAD 3368). The fungus had the following morphology: conidiophores cylindrical, geniculate, proliferating sympodially, 53 to 380 µm × 3 to 6.5 µm, 3 to 15-septate, smooth, with thickened and dark conidial scars, brown; conidia acicular to filiform, 47 to 210 µm × 2.5 to 5 µm, 3 to 17-septate, thin­walled, smooth, with thickened and dark hila, hyaline. This combination is typical of Cercospora apii sensu lato, as described by Crous and Braun (2003). Genomic DNA was extracted from a 7-day-old culture of COAD 3368 and three loci were PCR amplified, namely: actin (ACT), with 512-F and 783-R primers; calmodulin (CAL), using the primers 228F and 2Rd; and histone H3 gene (HIS3), with the primers CYLH3F and CYLH3R. PCR products were sequenced by Macrogen (Seoul, South Korea) and the resulting sequences were deposited in GenBank (OM677624, OM677625 and OM677626, respectively). A multilocus Bayesian phylogenetic grouped COAD 3368 with Cercospora 'sp. Q' (Groenewald et al. 2013). This is a yet unresolved species complex within C. apii. Six 6­month­old healthy hop plants (cv. Cascade) were sprayed with a COAD 3368 conidial suspension (105 conidia/ mL) whereas another group of six plants was sprayed with sterile distilled water, serving as controls. Plants were placed in a dew chamber for 5 days and then transferred to a greenhouse bench, where they were observed daily. Thirty days after inoculation, symptoms similar to those observed in the field had developed on all inoculated plants, whereas control plants remained healthy. The fungus growing on inoculated hops produced typical Cercospora conidiophores and conidia. Upon reisolation, pure cultures with the same morphology of COAD 3368 were obtained. There are no previous records of Cercospora 'sp. Q' on hops worldwide. Fungi in Cercospora 'sp. Q' are known to have a broad host-range. A previous record of Cercospora 'sp. Q' leaf spots was published from its observation on Dioscorea cayennensis in the Infectarium (Torres et al. 2016). Damage to the hop plants was severe and it is possible that Cercospora leaf spot will become an emerging threat to commercial hop plantations in Brazil.

19.
Sensors (Basel) ; 22(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36236304

RESUMO

In source localization problems, the relative geometry between sensors and source will influence the localization performance. The optimum configuration of sensors depends on the measurements used for the source location estimation, how these measurements are affected by noise, the positions of the source, and the criteria used to evaluate the localization performance. This paper addresses the problem of optimum sensor placement in a plane for the localization of an underwater vehicle moving in 3D. We consider sets of sensors that measure the distance to the vehicle and model the measurement noises with distance dependent covariances. We develop a genetic algorithm and analyze both single and multi-objective problems. In the former, we consider as the evaluation metric the arithmetic average along the vehicle trajectory of the maximum eigenvalue of the inverse of the Fisher information matrix. In the latter, we estimate the Pareto front of pairs of common criteria based on the Fisher information matrix and analyze the evolution of the sensor positioning for the different criteria. To validate the algorithm, we initially compare results with a case with a known optimal solution and constant measurement covariances, obtaining deviations from the optimal less than 0.1%. Posterior, we present results for an underwater vehicle performing a lawn-mower maneuver and a spiral descent maneuver. We also present results restricting the allowed positions for the sensors.

20.
Photochem Photobiol Sci ; 20(10): 1309-1321, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34562236

RESUMO

The initial objective of our work was to synthesize a series of 2-amino-4H-pyran-3-carbonitriles to be tested for their antifungal activities against economically relevant phytopathogenic fungi. Fourteen compounds were prepared in up to 94% yield and shown percentages of Botrytis cinerea inhibition above 70%. Despite the promising biological results, we observed that stock solutions prepared for biological tests showed color changing when kept for a few days on the laboratory bench, under room conditions, illuminated by common LED daylight tubes (4500-6000 k). This prompted us to investigate the possible photo-induced degradation of our compounds. FT-IR ATR experiments evidenced variations in the expected bands for functional of -amino-4H-pyran-3-carbonitriles stored under LED daylight. Following, HPLC-UV analysis showed reductions in the intensity of chromatographic peaks of 2-amino-4H-pyran-3-carbonitriles, and but not for solutions kept in the dark. A solution of (E)-2-amino-8-(4-nitrobenzylidene)-4-(4-nitrophenyl)-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile underwent 84.4% of conversion after 72 h of exposure to continuous LED daylight in a BOD chamber, and the reaction product was isolated in 36% yield and characterized as (E)-7-cyano-5-(4-nitrobenzylidene)-8-(4-nitrophenyl)bicyclo[4.2.0]oct-1(6)-ene-7-carboxamide (7*). Despite freshly prepared solutions of 2-amino-4H-pyran-3-carbonitriles produced antifungal activities, these solutions lost biological activity when left on the bench for a week. Besides, compound 7* formed from photo-induced degradation of 7 also showed no antifungal activity. With this, we hope to bring two contributions: (1) production of cyclobutenes through photochemical reactions of 2-amino-4H-pyran-3-carbonitriles can be carried out through exposure to simple white LED daylight; (2) biological applications of such 2-amino-4H-pyran-3-carbonitriles may be impaired by their poor photostability.


Assuntos
Antifúngicos/farmacologia , Botrytis/efeitos dos fármacos , Luz , Piranos/química , Antifúngicos/síntese química , Antifúngicos/química , Cromatografia Líquida de Alta Pressão , Conformação Molecular , Fotólise/efeitos da radiação , Piranos/síntese química , Piranos/farmacologia , Espectrofotometria Ultravioleta
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa