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1.
J Biol Inorg Chem ; 25(8): 1117-1128, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33104887

RESUMO

Invasive fungal infections (IFIs) are life threatening and existing antifungal drugs are not completely effective due to undesirable side effects and resistance emergence. Azoles are often the treatment of choice for IFIs and growing evidence suggests that copper can act synergistically with these drugs. In this work, we designed a compound bringing together azole and copper(II)-binding groups and studied the molecular mechanisms underlying its biological toxicity. Our results show that both the compound, 4, and its copper(II) complex, Cu.4, are active against Candida spp. We found that Cu.4 acts as a copper(II) ionophore, which results in the intracellular accumulation of reactive oxygen species (ROS), whereas compound 4 is an iron chelator and exerts its toxicity by decreasing iron bioavailability. Interestingly, while 4 is not very toxic to macrophages or HeLa cells, Cu.4 significantly affects their viability. Overall, this work provides evidence of how copper can be combined with azoles to deregulate copper homeostasis, opening new horizons for the development of bifunctional antifungals.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Cobre/química , Ionóforos/química , Triazóis/química , Triazóis/farmacologia , Antifúngicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Triazóis/toxicidade
2.
World J Microbiol Biotechnol ; 34(7): 87, 2018 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-29886562

RESUMO

Drought is one of the environmental factors that most affects peanut cultivation in semi-arid regions, resulting in economic losses to growers. However, growth promoting bacteria are able to reduce water deficit damage in some plant species. In this context, this study aimed to evaluate the interaction of Bradyrhizobium strains reducing water stress effects on peanut genotypes by antioxidant enzymes activities, leaf gas exchanges and vegetative growth, as well as to determine the taxonomic positioning of strain ESA 123. The 16S rRNA gene of ESA 123 was amplified by PCR and sequenced by dideoxy Sanger sequencing method. An experiment was performed in greenhouse with three peanut genotypes (BRS Havana, CNPA 76 AM and 2012-4), two Bradyrhizobium strains (SEMIA 6144 and ESA 123), a mineral source of N and an absolute control (without N) under two water regimes (with and without irrigation). Seeds of peanut were sown and the plants were grown until 30 days after emergence. On the 20th day, the water deficit plants group had their irrigation suspended for 10 days. At in silico analyzes, ESA 123 presented 98.97% similarity with the type strain of B. kavangense. Leaf gas exchange was affected by water deficit; as well as alteration of antioxidant activities and reduction of vegetative growth variables. However, some plants inoculated with SEMIA 6144 and ESA 123 strains presented lower reductions and increment of some evaluated variables, mainly the ones inoculated with the ESA 123 strain, Bradyrhizobium sp. from the semi-arid region of Northeast Brazil. This data suggests beneficial effects of the peanut-Bradyrhizobium interaction in a water stress condition, specially with the ESA 123 strain.


Assuntos
Arachis/microbiologia , Arachis/fisiologia , Bradyrhizobium/fisiologia , Secas , Antioxidantes , Arachis/crescimento & desenvolvimento , Bradyrhizobium/classificação , Bradyrhizobium/genética , Bradyrhizobium/isolamento & purificação , Brasil , Filogenia , Folhas de Planta/fisiologia , Raízes de Plantas/microbiologia , Brotos de Planta/microbiologia , RNA Ribossômico 16S/genética , Sementes , Microbiologia do Solo , Estresse Fisiológico , Simbiose , Água
3.
J Dairy Sci ; 100(6): 4565-4573, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28390718

RESUMO

The objective of this study was to evaluate 2 systems for covering corn silage in bunker silos. The first system consisted of a sheet of 45-µm-thick oxygen barrier film (OB, polyethylene + ethylene-vinyl alcohol) placed along the length of the sidewall before filling. After filling, the excess film was pulled over the wall on top of the silage, and a sheet of polyethylene was placed on top. The second system involved using a standard sheet (ST) of 180-µm-thick polyethylene film. Eight commercial bunker silos were divided into 2 parts lengthwise so that one-half of the silo was covered with OB and the other half with a ST system. During the filling, 3 net bags with chopped corn were buried in the central part (halfway between the top and bottom of the silo) of the bunkers (CCOR) in 3 sections 10 m apart. After filling, 18 net bags (9 per covering system) were buried 40 cm below the top surface of the 3 sections. These bags were placed at 3 distances from the bunker walls (0 to 50 cm, 51 to 100 cm, and 101 to 150 cm). During unloading, the bags were removed from the silos to determine the dry matter (DM) losses, fermentation end products, and nutritive value. The Milk2006 spreadsheet was used to estimate milk per tonne of DM. The model included the fixed effect of treatment (7 different locations in the bunker) and the random effect of the silo. Two contrasts were tested to compare silages in the top laterals (shoulders) with that in the CCOR (CCOR vs. OB and CCOR vs. ST). Three contrasts compared the corresponding distances of the silage covered by the 2 systems (OB50 vs. ST50, OB100 vs. ST100 and OB150 vs. ST150). Variables were analyzed with the PROC MIXED procedure of the SAS at the 5% level. The OB method produced well-fermented silages, which were similar to CCOR, whereas the OB system showed less lactic acid and greater pH and mold counts compared with CCOR. The ST method had 116.2 kg of milk/t less than the CCOR, as the OB system and the CCOR were similar (1,258.3 and 1,294.0 kg/t, respectively). Regarding the distances from the walls, the effects were more pronounced from 0 to 101 cm. The OB50 and OB100 silages had better quality and lower mold counts and DM losses than ST50 and ST100. The OB system reduced DM and nutrient losses at the shoulders in farm bunker corn silages compared with no sidewall plastic. The OB film should lap onto the crop for at least 200 cm so that 150 cm are covered outward from the wall.


Assuntos
Fermentação , Armazenamento de Alimentos/métodos , Valor Nutritivo , Oxigênio , Plásticos/química , Silagem , Zea mays , Criação de Animais Domésticos , Animais , Etanol , Armazenamento de Alimentos/instrumentação , Concentração de Íons de Hidrogênio , Ácido Láctico/análise , Polietileno , Compostos de Vinila
5.
Spinal Cord ; 54(6): 423-30, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26439843

RESUMO

STUDY DESIGN: Experimental study. OBJECTIVE: Several neuro-degenerative disorders such as Alzheimer's dementia, Parkinson's disease and amyotrophic lateral sclerosis (ALS) are associated with genetic mutations, and replacing or disrupting defective sequences might offer therapeutic benefits. Single gene delivery has so far failed to achieve significant clinical improvements in humans, leading to the advent of co-expression of multiple therapeutic genes. Co-transfection using two or more individual constructs might inadvertently result in disproportionate delivery of the products into the cells. To prevent this, and in order to rule out interference among the many promoters with varying strength, expressing multiple proteins in equimolar amounts can be achieved by linking open reading frames under the control of only one promoter. SETTING: Kazan, Russian Federation. METHODS: Here we describe a strategy for adeno-viral co-expression of vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF2) interconnected through picorna-viral 2A-amino-acid sequence in transfected human umbilical cord blood mono-nuclear cells (hUCB-MCs). RESULTS: Presence of both growth factors, as well as absence of immune response to 2A-antigen, was demonstrated after 28-52 days. Following injection of hUCB-MCs into ALS transgenic mice, co-expression of VEGF and FGF2, as well as viable xeno-transplanted cells, were observed in the spinal cord after 1 month. CONCLUSION: These results suggest that recombinant adeno-virus containing 2A-sequences could serve as a promising alternative in regenerative medicine for the delivery of therapeutic molecules to treat neurodegenerative diseases, such as ALS.


Assuntos
Esclerose Lateral Amiotrófica/terapia , Células Sanguíneas/metabolismo , Células Sanguíneas/transplante , Cisteína Endopeptidases/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Virais/metabolismo , Adenoviridae/genética , Esclerose Lateral Amiotrófica/genética , Animais , Cisteína Endopeptidases/genética , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Sangue Fetal/citologia , Fator 2 de Crescimento de Fibroblastos/genética , Vetores Genéticos/fisiologia , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Mutação/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Superóxido Dismutase-1/genética , Transfecção , Fator A de Crescimento do Endotélio Vascular/genética , Proteínas Virais/genética
6.
Genet Mol Res ; 14(3): 7386-94, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26214417

RESUMO

Gene sequences previously identified in Arabidopsis buds were used as references in order to estimate temporal and tissue expression in buds, leaves, stem, and root tissues in cotton plants. Buds were evaluated during 3 phases: 2-8, 10-12, and 14-20 mm. Primers were designed for the ARF6, ATFY, and SEUSS genes for use in semi-quantitative reverse transcription-polymerase chain reaction and quantitative reverse transcription-polymerase chain reaction. Different levels of expression of the 3 genes were confirmed in cotton buds as well as in other tissues. The peak of gene expression was observed in buds sized 10-12 mm, after which expression decreased in larger buds. The gene GhFYPP3 was the most promising for further prospection of promoter regions, with regular expression patterns observed in bud sizes 10-12 and 14-20 mm. This trait was not observed in others genes.


Assuntos
Gossypium/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência , Análise Espaço-Temporal , Transcriptoma
7.
Genet Mol Res ; 12(1): 37-43, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23359022

RESUMO

A subtractive cDNA library from cotton buds was constructed to prospect for differentially expressed genes related to early bud development. A library was constructed and 768 cDNA sequences were obtained, comprising 168 clusters, with 126 contigs and 42 singlets. Both the Gossypium as well as Arabidopsis databases were utilized for the in silico analysis, since some genes identified in cotton have not yet been studied for functionality, although they have homology with genes from other species. The transcriptome revealed a large number of transcripts, some of them with unknown function, and others related to pollen development, pollen tubes, ovules, and fibers at different stages. The most populated contig was identified as fiber from 0-10 days after anthesis, with 12 reads. The success and novelty rates generated from the library were 67 and 51%, respectively. The information obtained here will provide a framework for research on functional cotton genomics.


Assuntos
Regulação da Expressão Gênica de Plantas , Genes de Plantas , Gossypium/crescimento & desenvolvimento , Gossypium/genética , Fibra de Algodão , DNA Complementar/genética , Biblioteca Gênica , Transcriptoma/genética
8.
Braz J Med Biol Res ; 56: e12955, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37937602

RESUMO

Neuropathic pain is a condition with varying origins, including reduced dietary micronutrient intake. Phytate is a polyphosphate found in seeds and grains that can act as an antinutrient due to the ability of sequester essential divalent metals. Here we tested whether moderate dietary phytate intake could alter nociceptive pain. We subjected weaning mice to a chow supplemented with 1% phytate for eight weeks. Body weight gain, glycemic responses, food ingestion, water ingestion, and liver and adipose tissue weights were not altered compared to controls. We observed a decreased mechanical allodynia threshold in the intervention group, although there were no changes in heat- or cold-induced pain. Animals consuming phytate showed reduced spinal cord tumor necrosis factor (TNF), indicating altered inflammatory process. These data provide evidence for a subclinical induction of mechanical allodynia that is independent of phytate consumption in animals with otherwise normal phenotypic pattern.


Assuntos
Hiperalgesia , Neuralgia , Camundongos , Animais , Hiperalgesia/etiologia , Ácido Fítico , Medula Espinal , Fator de Necrose Tumoral alfa
9.
Braz J Biol ; 82: e235475, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105661

RESUMO

Plants that produce secondary metabolites with allelopathic activity or phytotoxicity can be biotechnologically important, serving as sources of allelochemicals, and thus contributing to the agroindustrial sector. Vismia japurensis (Hypericaceae) is an Amazonian species that grows in clumps called vismiais, from which most other plants are absent. Accordingly, the objective of this study was to identify possible phytotoxicity effects of hexane and methanol extracts of Vismia japurensis leaves and branches in vivo and from seedlings grown in vitro on Lactuca sativa. In addition, fresh and dry leaves were assayed by the sandwich method in order to determine their ability to release allelochemicals. The hexanic extract from in vitro seedlings reduced germination by 10%, while the methanol extract produced a 16% reduction in germination speed. Root growth of Lactuca sativa was inhibited by 64.7% when subjected to hexane leaf extract, by 39.3% under the influence of hexane branch extract, and by 96.09% for in vitro seedling hexanic extract. When analysed by thin layer chromatography and 1H nuclear magnetic resonance, extracts showed evidence of terpenes, anthraquinones and flavonoids, with greater intensity of signals in the aromatic region of in vitro seedling hexanic extract. Clearly, Vismia japurensis has a high biotechnological potential in terms of the production of substances of low polarity with capacity to interfere in plant development.


Assuntos
Clusiaceae , Germinação , Alelopatia , Extratos Vegetais/toxicidade , Folhas de Planta , Plântula
10.
Domest Anim Endocrinol ; 74: 106532, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32841886

RESUMO

Amylin is a pancreatic hormone cosecreted along with insulin and involved in pancreatic amyloidosis and ß-cell apoptosis in diabetic cats and humans. Amylin is usually elevated in early stages of type 2 diabetes but recently was found to be increased in acute and chronic pancreatitis in humans. Currently, there are little data about feline amylin propensity to fibrillate and no information on circulating levels of this hormone during feline pancreatitis. We compared 4 amylin analogues and found cat amylin to be more prone to amyloid fibrillation than human amylin, the triple-proline analogue pramlintide and rat amylin. We also measured plasma amylin levels in healthy lean cats, diabetic cats, and cats with pancreatitis. Plasma amylin was higher in diabetic cats compared with healthy lean cats (P < 0.001). Interestingly, amylin levels during pancreatitis were higher than those of both lean cats (P < 0.0001) and diabetic cats without pancreatitis (P < 0.005). These data support evidence of feline amylin being more prone to aggregation than human amylin in vitro, which may influence diabetes mellitus progression and ß-cell failure in vivo. Furthermore, our data show an increase in amylin levels during feline pancreatitis and the need for future research on the role of this hormone in the pathogenesis of pancreatic inflammation associated to feline diabetes mellitus.


Assuntos
Doenças do Gato/patologia , Diabetes Mellitus/veterinária , Polipeptídeo Amiloide das Ilhotas Pancreáticas/sangue , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Pancreatite/veterinária , Animais , Estudos de Casos e Controles , Doenças do Gato/sangue , Gatos , Diabetes Mellitus/sangue , Diabetes Mellitus/metabolismo , Feminino , Masculino , Pancreatite/sangue , Pancreatite/metabolismo , Agregação Patológica de Proteínas
11.
Minerva Stomatol ; 58(3): 93-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19357615

RESUMO

AIM: The aim of this in vitro study was to compare an ultrasonic diamond tip to a high-speed conventional diamond bur regarding the cutting effectiveness in enamel and dentin of human teeth. METHODS: Twenty permanent molars were longitudinally sectioned in the buccal-lingual plane giving 40 specimens, 20 for enamel and 20 for dentin groups. One cavity was performed in each specimen using a spherical diamond tip (83231, CVDentus(R), CVDVale, São José dos Campos, SP, Brazil) coupled with an ultrasound device or a conventional spherical diamond bur (1013, KG Sorensen, São Paulo, Brazil)) coupled with a high-speed turbine. A modified measurement analysis using the Radiocef 4.0 software (Radiocef Memory) was applied to determine the width and the depth of the cavities on scanning electron microscopy (SEM) at x50 magnification micrographs. The features of the cavities and the characteristics of the cutting instruments were also examined under different magnifications by SEM. RESULTS: Statistical analysis by Kruskal-Wallis non-parametric and Dunn post hoc tests (P < or = 0.05) showed that cavities prepared in enamel and dentin with the ultrasonic diamond tip were shallower and narrower than those prepared with conventional diamond bur. The internal walls of cavities prepared in dentin by the ultrasonic diamond tip reproduced the superficial aspect of the diamond, however, scratches were observed in the internal walls of the dentin cut by high-speed conventional diamond bur. CONCLUSIONS: Both instruments were effective in enamel and dentin cutting; however, cavities prepared with a high-speed conventional diamond bur showed more invasive characteristics.


Assuntos
Preparo da Cavidade Dentária/instrumentação , Equipamentos Odontológicos de Alta Rotação , Instrumentos Odontológicos , Ultrassom , Adolescente , Esmalte Dentário/ultraestrutura , Dentina/ultraestrutura , Diamante , Feminino , Humanos , Técnicas In Vitro , Masculino , Microscopia Eletrônica de Varredura , Dente Serotino/ultraestrutura , Distribuição Aleatória , Adulto Jovem
12.
Protein Pept Lett ; 15(9): 1022-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991781

RESUMO

The digestive system of P. interpunctella was characterized during its larval development to determination of carbohydrases using disaccharides (sucrose and maltose) and polysaccharides (starch and inulin) as substrate. At 6(th) instar larval, Invertase>alpha-amylase> maltase activities peaks were observed. Invertase was fractionated with acetone and isolated. The Invertase was 485.5 fold purified by Sephacryl S-200 and DEAE-Sephadex. Its kinetic parameters were K(m) of 6.6 mM, V(max) of 0.48, pH optimum of 5.5 and temperature optimum of 30 degrees C. This enzyme was activated by CaCl(2) and inhibited by EDTA. When analyzed by SDS-PAGE it showed one band of M(r) 34 kDa. The understanding of the digestive system of P. interpunctella could be a key step in the design of bioinsecticides.


Assuntos
Mariposas/enzimologia , beta-Frutofuranosidase/isolamento & purificação , beta-Frutofuranosidase/metabolismo , Animais , Eletroforese em Gel de Poliacrilamida , Ativadores de Enzimas/farmacologia , Inibidores Enzimáticos/farmacologia , Glicosídeo Hidrolases/isolamento & purificação , Concentração de Íons de Hidrogênio , Cinética , Larva/enzimologia , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Temperatura
13.
Braz. j. med. biol. res ; 56: e12955, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1520478

RESUMO

Neuropathic pain is a condition with varying origins, including reduced dietary micronutrient intake. Phytate is a polyphosphate found in seeds and grains that can act as an antinutrient due to the ability of sequester essential divalent metals. Here we tested whether moderate dietary phytate intake could alter nociceptive pain. We subjected weaning mice to a chow supplemented with 1% phytate for eight weeks. Body weight gain, glycemic responses, food ingestion, water ingestion, and liver and adipose tissue weights were not altered compared to controls. We observed a decreased mechanical allodynia threshold in the intervention group, although there were no changes in heat- or cold-induced pain. Animals consuming phytate showed reduced spinal cord tumor necrosis factor (TNF), indicating altered inflammatory process. These data provide evidence for a subclinical induction of mechanical allodynia that is independent of phytate consumption in animals with otherwise normal phenotypic pattern.

14.
Braz. j. biol ; 82: 1-7, 2022. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468482

RESUMO

Plants that produce secondary metabolites with allelopathic activity or phytotoxicity can be biotechnologically important, serving as sources of allelochemicals, and thus contributing to the agroindustrial sector. Vismia japurensis (Hypericaceae) is an Amazonian species that grows in clumps called vismiais, from which most other plants are absent. Accordingly, the objective of this study was to identify possible phytotoxicity effects of hexane and methanol extracts of Vismia japurensis leaves and branches in vivo and from seedlings grown in vitro on Lactuca sativa. In addition, fresh and dry leaves were assayed by the sandwich method in order to determine their ability to release allelochemicals. The hexanic extract from in vitro seedlings reduced germination by 10%, while the methanol extract produced a 16% reduction in germination speed. Root growth of Lactuca sativa was inhibited by 64.7% when subjected to hexane leaf extract, by 39.3% under the influence of hexane branch extract, and by 96.09% for in vitro seedling hexanic extract. When analysed by thin layer chromatography and 1H nuclear magnetic resonance, extracts showed evidence of terpenes, anthraquinones and flavonoids, with greater intensity of signals in the aromatic region of in vitro seedling hexanic extract. Clearly, Vismia japurensis has a high biotechnological potential in terms of the production of substances of low polarity with capacity to interfere in plant development.


Plantas que produzem metabólitos secundários com atividade alelopática ou fitotóxica podem ser biotecnologicamente importantes, servindo como fontes de aleloquímicos e, assim, contribuindo para o setor agroindustrial. Vismia japurensis (Hypericaceae) é uma espécie amazônica que cresce em grupos, formando vismiais. Assim, o objetivo deste estudo foi identificar possíveis efeitos fitotóxicos de extratos hexânicos e metanólicos de folhas e ramos de Vismia japurensis in vivo e de plântulas cultivadas in vitro sobre Lactuca sativa. Além disso, folhas frescas e secas foram analisadas pelo método sanduíche, a fim de determinar sua capacidade de liberação de aleloquímicos. O extrato hexânico de plântulas in vitro reduziu a germinação em 10% e o extrato metanólico promoveu uma redução de 16% na velocidade de germinação. O crescimento radicular de Lactuca sativa foi inibido em 64,7% quando submetido ao extrato hexânico das folhas, em 39,3% sob influência do extrato hexânico dos galhos e em 96,09% para o extrato de hexânico das plântulas in vitro. Quando analisados por cromatografia em camada delgada e ressonância magnética nuclear de 1H, os extratos mostraram evidências de terpenos, antraquinonas e flavonoides, com maior intensidade de sinais na região aromática do extrato hexânico das plântulas in vitro. Assim, Vismia japurensis possui elevado potencial biotecnológico em termos de produção de substâncias de baixa polaridade com capacidade de interferência no desenvolvimento de plantas.


Assuntos
Lactuca/efeitos dos fármacos , Antraquinonas , Clusiaceae/química , Clusiaceae/toxicidade , Terpenos , Técnicas In Vitro
15.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468669

RESUMO

Abstract Plants that produce secondary metabolites with allelopathic activity or phytotoxicity can be biotechnologically important, serving as sources of allelochemicals, and thus contributing to the agroindustrial sector. Vismia japurensis (Hypericaceae) is an Amazonian species that grows in clumps called vismiais, from which most other plants are absent. Accordingly, the objective of this study was to identify possible phytotoxicity effects of hexane and methanol extracts of Vismia japurensis leaves and branches in vivo and from seedlings grown in vitro on Lactuca sativa. In addition, fresh and dry leaves were assayed by the sandwich method in order to determine their ability to release allelochemicals. The hexanic extract from in vitro seedlings reduced germination by 10%, while the methanol extract produced a 16% reduction in germination speed. Root growth of Lactuca sativa was inhibited by 64.7% when subjected to hexane leaf extract, by 39.3% under the influence of hexane branch extract, and by 96.09% for in vitro seedling hexanic extract. When analysed by thin layer chromatography and 1H nuclear magnetic resonance, extracts showed evidence of terpenes, anthraquinones and flavonoids, with greater intensity of signals in the aromatic region of in vitro seedling hexanic extract. Clearly, Vismia japurensis has a high biotechnological potential in terms of the production of substances of low polarity with capacity to interfere in plant development.


Resumo Plantas que produzem metabólitos secundários com atividade alelopática ou fitotóxica podem ser biotecnologicamente importantes, servindo como fontes de aleloquímicos e, assim, contribuindo para o setor agroindustrial. Vismia japurensis (Hypericaceae) é uma espécie amazônica que cresce em grupos, formando vismiais. Assim, o objetivo deste estudo foi identificar possíveis efeitos fitotóxicos de extratos hexânicos e metanólicos de folhas e ramos de Vismia japurensis in vivo e de plântulas cultivadas in vitro sobre Lactuca sativa. Além disso, folhas frescas e secas foram analisadas pelo método sanduíche, a fim de determinar sua capacidade de liberação de aleloquímicos. O extrato hexânico de plântulas in vitro reduziu a germinação em 10% e o extrato metanólico promoveu uma redução de 16% na velocidade de germinação. O crescimento radicular de Lactuca sativa foi inibido em 64,7% quando submetido ao extrato hexânico das folhas, em 39,3% sob influência do extrato hexânico dos galhos e em 96,09% para o extrato de hexânico das plântulas in vitro. Quando analisados por cromatografia em camada delgada e ressonância magnética nuclear de 1H, os extratos mostraram evidências de terpenos, antraquinonas e flavonoides, com maior intensidade de sinais na região aromática do extrato hexânico das plântulas in vitro. Assim, Vismia japurensis possui elevado potencial biotecnológico em termos de produção de substâncias de baixa polaridade com capacidade de interferência no desenvolvimento de plantas.

16.
Braz. j. biol ; 82: e235475, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1249240

RESUMO

Plants that produce secondary metabolites with allelopathic activity or phytotoxicity can be biotechnologically important, serving as sources of allelochemicals, and thus contributing to the agroindustrial sector. Vismia japurensis (Hypericaceae) is an Amazonian species that grows in clumps called vismiais, from which most other plants are absent. Accordingly, the objective of this study was to identify possible phytotoxicity effects of hexane and methanol extracts of Vismia japurensis leaves and branches in vivo and from seedlings grown in vitro on Lactuca sativa. In addition, fresh and dry leaves were assayed by the sandwich method in order to determine their ability to release allelochemicals. The hexanic extract from in vitro seedlings reduced germination by 10%, while the methanol extract produced a 16% reduction in germination speed. Root growth of Lactuca sativa was inhibited by 64.7% when subjected to hexane leaf extract, by 39.3% under the influence of hexane branch extract, and by 96.09% for in vitro seedling hexanic extract. When analysed by thin layer chromatography and 1H nuclear magnetic resonance, extracts showed evidence of terpenes, anthraquinones and flavonoids, with greater intensity of signals in the aromatic region of in vitro seedling hexanic extract. Clearly, Vismia japurensis has a high biotechnological potential in terms of the production of substances of low polarity with capacity to interfere in plant development.


Plantas que produzem metabólitos secundários com atividade alelopática ou fitotóxica podem ser biotecnologicamente importantes, servindo como fontes de aleloquímicos e, assim, contribuindo para o setor agroindustrial. Vismia japurensis (Hypericaceae) é uma espécie amazônica que cresce em grupos, formando vismiais. Assim, o objetivo deste estudo foi identificar possíveis efeitos fitotóxicos de extratos hexânicos e metanólicos de folhas e ramos de Vismia japurensis in vivo e de plântulas cultivadas in vitro sobre Lactuca sativa. Além disso, folhas frescas e secas foram analisadas pelo método sanduíche, a fim de determinar sua capacidade de liberação de aleloquímicos. O extrato hexânico de plântulas in vitro reduziu a germinação em 10% e o extrato metanólico promoveu uma redução de 16% na velocidade de germinação. O crescimento radicular de Lactuca sativa foi inibido em 64,7% quando submetido ao extrato hexânico das folhas, em 39,3% sob influência do extrato hexânico dos galhos e em 96,09% para o extrato de hexânico das plântulas in vitro. Quando analisados por cromatografia em camada delgada e ressonância magnética nuclear de 1H, os extratos mostraram evidências de terpenos, antraquinonas e flavonoides, com maior intensidade de sinais na região aromática do extrato hexânico das plântulas in vitro. Assim, Vismia japurensis possui elevado potencial biotecnológico em termos de produção de substâncias de baixa polaridade com capacidade de interferência no desenvolvimento de plantas.


Assuntos
Germinação , Clusiaceae , Extratos Vegetais/toxicidade , Folhas de Planta , Plântula , Alelopatia
17.
Braz J Med Biol Res ; 39(2): 283-7, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16470317

RESUMO

The aim of the present study was to compare the efficacy of a novel phosphodiesterase 4 and 5 inhibitor, LASSBio596, with that of dexamethasone in a murine model of chronic asthma. Lung mechanics (airway resistance, viscoelastic pressure, and static elastance), histology, and airway and lung parenchyma remodeling (quantitative analysis of collagen and elastic fiber) were analyzed. Thirty-three BALB/c mice were randomly assigned to four groups. In the asthma group (N = 9), mice were immunized with 10 microg ovalbumin (OVA, ip) on 7 alternate days, and after day 40 they were challenged with three intratracheal instillations of 20 microg OVA at 3-day intervals. Control mice (N = 8) received saline under the same protocol. In the dexamethasone (N = 8) and LASSBio596 (N = 8) groups, the animals of the asthma group were treated with 1 mg/kg dexamethasone disodium phosphate (0.1 mL, ip) or 10 mg/kg LASSBio596 dissolved in dimethyl sulfoxide (0.2 mL, ip) 24 h before the first intratracheal instillation of OVA, for 8 days. Airway resistance, viscoelastic pressure and static elastance increased significantly in the asthma group (77, 56, and 76%, respectively) compared to the control group. The asthma group presented more intense alveolar collapse, bronchoconstriction, and eosinophil and neutrophil infiltration than the control group. Both LASSBio596 and dexamethasone inhibited the changes in lung mechanics, tissue cellularity, bronchoconstriction, as well as airway and lung parenchyma remodeling. In conclusion, LASSBio596 at a dose of 10 mg/kg effectively prevented lung mechanical and morphometrical changes and had the potential to block fibroproliferation in a BALB/c mouse model of asthma.


Assuntos
Asma/tratamento farmacológico , Inibidores de Fosfodiesterase/farmacologia , Ftalimidas/farmacologia , Mecânica Respiratória/efeitos dos fármacos , Animais , Asma/patologia , Doença Crônica , Dexametasona/farmacologia , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos BALB C , Ácidos Ftálicos , Distribuição Aleatória , Testes de Função Respiratória , Sulfonamidas
18.
Oper Dent ; 31(3): 371-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16802646

RESUMO

This study determined the size of aluminum oxide particles used in an air abrasion system that is able to remove carious dentin tissue with maximum preservation of sound structure. Thirty extracted and carious-free third molars were used in this study. The dentin sample was obtained by sectioning the middle of the crown longitudinal to the long axis of the tooth in a mesio-distal direction. One half of the crown corresponded to the sound dentin group (SD), while the other half was used to develop artificial caries, constituting the carious dentin group (CD). The specimens were air abraded for 15 seconds. The SD and CD groups were each randomly divided into three subgroups (N=10) according to the particle diameter employed (27, 50 and 125 microm). The prepared cavity was perpendicularly cut in half, and the profiles of all hemi-fragments were observed using SEM microscopy. The cavity measurements were made using a modified cephalometric analysis. The 27, 50 and 125 microm aluminum oxide particles did not present selectivity in the removal of carious dentin. However, when using the air abrasive technique for carious dentin treatment, the use of 27 and 50 microm aluminum oxide particles is recommended, due to their capacity to remove less sound tissue than the 125 microm particles.


Assuntos
Abrasão Dental por Ar/métodos , Óxido de Alumínio/uso terapêutico , Cárie Dentária/terapia , Materiais Dentários/uso terapêutico , Dentina/ultraestrutura , Óxido de Alumínio/química , Cárie Dentária/microbiologia , Cárie Dentária/patologia , Preparo da Cavidade Dentária/métodos , Materiais Dentários/química , Humanos , Lactobacillus acidophilus/fisiologia , Teste de Materiais , Microscopia Eletrônica de Varredura , Dente Serotino , Odontometria , Tamanho da Partícula , Streptococcus mutans/fisiologia
19.
Methods Enzymol ; 580: 333-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27586340

RESUMO

Peptides are multidentate chiral ligands capable of coordinating different metal ions. Nowadays, they can be obtained with high yield and purity, thanks to the advances on peptide/protein chemistry as well as in equipment (peptide synthesizers). Based on the identity and length of their amino acid sequences, peptides can present different degrees of flexibility and folding. Although short peptide sequences (<20 amino acids) usually lack structure in solution, different levels of structural preorganization can be induced by introducing conformational constraints, such as ß-turn/loop template sequences and backbone cyclization. For all these reasons, and the fact that one is not restricted to use proteinogenic amino acids, small peptidic scaffolds constitute a simple and versatile platform for the development of inorganic systems with tailor-made properties and functions. Here we outline a general approach to the design of short preorganized peptide sequences (10-16 amino acids) for metal ion coordination. Based on our experience, we present a general scheme for the design, synthesis, and characterization of these peptidic scaffolds and provide protocols for the study of their metal ion coordination properties.


Assuntos
Aminoácidos/química , Cobre/química , Peptídeos/química , Engenharia de Proteínas/métodos , Sequência de Aminoácidos/genética , Aminoácidos/genética , Íons/química , Ligantes , Peptídeos/genética
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