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1.
Chem Biodivers ; : e202401315, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136528

RESUMO

We have synthesized a series of novel coumarin-steroid and triterpenoid hybrids and evaluated their potential anticancer activity through molecular docking calculations and in vitro antiproliferative assays. These hybrids, derived from estrone and oleanolic acid, were linked via hydrocarbon spacers of varying lengths. Molecular docking studies against human aromatase revealed strong interactions, particularly for compound 11d, which exhibited significant binding affinity (-12.6308 kcal/mol). In vitro assays demonstrated that compounds 6b and 11d had notable antiproliferative effects, with GI50 values of 5.4 and 7.0 µM against WiDr (colon) and HeLa (cervix) cancer cells, respectively. These findings highlight the potential of these hybrids as novel anticancer agents targeting aromatase, warranting further investigation and optimization.

2.
Carbohydr Polym ; 342: 122324, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39048213

RESUMO

The system of polysaccharides from Schizymenia dubyi (Nemastomatales) was investigated. It contains a mixture of hybrid dl galactans (SH-S) and carrageenan-like polysaccharides, which were separated by means of precipitation with KCl at high concentrations. The structural features of the carrageenan-like fraction (SH-I) were investigated by methylation analysis, desulfation, uronic acid reduction, and NMR spectroscopy. It was concluded that the structure has the typical alternance α-(1 â†’ 3), ß-(1 â†’ 4) of d-galactose units, with most of the 3-linked units sulfated in O-2 (and some in O-4), and most of the 4-linked units sulfated in O-3, and substituted in O-2 by single stubs of ß-d-glucuronic acid (partly sulfated in each of the three available positions). This substituent has been only seldom found in red seaweed galactans. Rheological studies of 5 % and 10 % w/v SH, SH-S and SH-I aqueous systems, either without ions, or in KCl or CaCl2 solution gave thickening behaviors. Their random coil conformations justify the pseudoplastic behavior observed in the viscosity versus shear rate curves. As SH-S and SH-I are both contained in SH, an interpenetrating network could form in SH between the glucurono-carrageenan and the agaran, as inferred from the mechanical spectra recorded in water, especially with potassium ion.


Assuntos
Carragenina , Reologia , Carragenina/química , Viscosidade , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Galactanos/química , Rodófitas/química , Espectroscopia de Ressonância Magnética
3.
Front Plant Sci ; 15: 1353991, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38463568

RESUMO

Patterns of genetic variation in crops are the result of multiple processes that have occurred during their domestication and improvement, and are influenced by their wild progenitors that often remain understudied. The locoto chile, Capsicum pubescens, is a crop grown mainly in mid-highlands of South-Central America. This species is not known from the wild and exists only as a cultigen. The evolutionary affinities and exact origin of C. pubescens have still not been elucidated, with hypotheses suggesting its genetic relatedness and origin to two wild putative ancestral Capsicum species from the Central Andes, C. eximium and C. cardenasii. In the current study, RAD-sequencing was applied to obtain genome-wide data for 48 individuals of C. pubescens and its wild allies representing different geographical areas. Bayesian, Maximum Likelihood and coalescent-based analytical approaches were used to reconstruct population genetic patterns and phylogenetic relationships of the studied species. The results revealed that C. pubescens forms a well-defined monotypic lineage closely related to wild C. cardenasii and C. eximium, and also to C. eshbaughii. The primary lineages associated with the diversification under domestication of C. pubescens were also identified. Although direct ancestor-descendant relationship could not be inferred within this group of taxa, hybridization events were detected between C. pubescens and both C. cardenasii and C. eximium. Therefore, although hybrid origin of C. pubescens could not be inferred, gene flow involving its wild siblings was shown to be an important factor contributing to its contemporary genetic diversity. The data allowed for the inference of the center of origin of C. pubescens in central-western Bolivia highlands and for better understanding of the dynamics of its gene pool. The results of this study are essential for germplasm conservation and breeding purposes, and provide excellent basis for further research of the locoto chile and its wild relatives.

4.
Expert Opin Drug Discov ; 19(4): 451-470, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38456452

RESUMO

INTRODUCTION: The current drug discovery paradigm of 'one drug, multiple targets' has gained attention from both the academic medicinal chemistry community and the pharmaceutical industry. This is in response to the urgent need for effective agents to treat multifactorial chronic diseases. The molecular hybridization strategy is a useful tool that has been widely explored, particularly in the last two decades, for the design of multi-target drugs. AREAS COVERED: This review examines the current state of molecular hybridization in guiding the discovery of multitarget small molecules. The article discusses the design strategies and target selection for a multitarget polypharmacology approach to treat various diseases, including cancer, Alzheimer's disease, cardiac arrhythmia, endometriosis, and inflammatory diseases. EXPERT OPINION: Although the examples discussed highlight the importance of molecular hybridization for the discovery of multitarget bioactive compounds, it is notorious that the literature has focused on specific classes of targets. This may be due to a deep understanding of the pharmacophore features required for target binding, making targets such as histone deacetylases and cholinesterases frequent starting points. However, it is important to encourage the scientific community to explore diverse combinations of targets using the molecular hybridization strategy.


Assuntos
Doença de Alzheimer , Descoberta de Drogas , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Polifarmacologia , Desenho de Fármacos
5.
Polymers (Basel) ; 16(4)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38399875

RESUMO

Hyaluronan (HA) is a natural biodegradable biopolymer; its biological functions include cell adhesion, cell proliferation, and differentiation as well as decreasing inflammation, angiogenesis, and regeneration of damaged tissue. This makes it a suitable candidate for fabricating nanomaterials with potential use in tissue engineering. However, HA nanofiber production is restricted due to the high viscosity, low evaporation rate, and high surface tension of HA solutions. Here, hybrids in the form of continuous and randomly aligned polyvinyl alcohol (PVA)-(HA)-siloxane nanofibers were obtained using an electrospinning process. PVA-HA fibers were crosslinked by a 3D siloxane organic-inorganic matrix via sol-gel that restricts natural hydrophilicity and stiffens the structure. The hybrid nanofiber mats were characterized by FT-IR, micro-Raman spectroscopy, SEM, and biological properties. The PVA/HA ratio influenced the morphology of the hybrid nanofibers. Nanofibers with high PVA content (10PVA-8 and 10PVA-10) form mats with few beaded nanofibers, while those with high HA content (5PVA-8 and 5PVA-10) exhibit mats with mound patterns formed by "ribbon-like" nanofibers. The hybrid nanofibers were used as mats to support osteoblast growth, and they showed outstanding biological properties supporting cell adhesion, cell proliferation, and cell differentiation. Importantly, the 5PVA-8 mats show 3D spherical osteoblast morphology; this suggests the formation of tissue growth. These novel HA-based nanomaterials represent a relevant advance in designing nanofibers with unique properties for potential tissue regeneration.

6.
Planta ; 259(3): 67, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38332313

RESUMO

MAIN CONCLUSION: The analysis of meiotic pairing affinities and genomic formulae in species and hybrids of Zea allowed us to speculate an evolutionary model to recreate the ancient polyploidization of maize and allied species. The meiotic pairing affinities and the genomic formulae analysis in Zea species and hybrids obtained in new and previous crosses, together with the molecular data known in the genus, allowed us to speculate an evolutionary model to attempt to recreate the ancient polyploidization process of Zea species. We propose that x = 5 semispecies are the ancestors of all modern species of the genus. The complex evolutionary process that originated the different taxa could be included hybridization between sympatric diploid ancestral semispecies (2n = 10) and recurrent duplication of the hybrid chromosome number, resulting in distinct auto- and allopolyploids. After the merger and doubling of independent genomes would have undergone cytological and genetical diploidization, implying revolutionary changes in genome organization and genic balance processes. Based on the meiotic behaviour of the 2n = 30 hybrids, that showed homoeology between the A subgenomes of all parental species, we propose that this subgenome A would be pivotal in all the species and would have conserved the rDNA sequences and the pairing regulator locus (PrZ). In the hypothetical model postulated here, the ancestral semispecies with the pivotal subgenome A would have had a wide geographic distribution, co-occurring and hybridizing with the semispecies harbouring B subgenomes, thus enabling sympatric speciation.


Assuntos
Poaceae , Zea mays , Zea mays/genética , Poaceae/genética , Poliploidia , Evolução Biológica , Análise Citogenética , Genoma de Planta/genética
7.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469277

RESUMO

Abstract Responses of three tomato (Lycopersicon esculentum Mill.) hybrids viz. 'Luanova', 'Savarona' and 'Tessera' to various doses (0, 0.5, 1.0, 1.5 and 2.0 g L-1) of soil application of humic acid (HA) were evaluated in terms of plant growth, productivity and quality of fruits, under greenhouse conditions, during 2011-12 and 2012-13. In addition to improved quality characteristics, higher values for yield and yield components were recorded for tomato fruits harvested from plants of 'Tessera' cultivar compared to those harvested from other hybrids tested, regardless of growing seasons. Plants from 'Luanova' cultivar were, however, earlier in fruiting with higher number of fruits per plant. Soil application of HA presented positive effects on yield and physicochemical quality of tomato fruits irrespective of the dose of HA and the cultivar investigated, in both seasons. Soil application of HA at higher dose 1.5 g L-1 exhibited better results in all the three tomato cultivars tested, in terms of their vegetative and reproductive growth, and significantly improved the physicochemical quality of their fruits. Conclusively, the tomato hybrid 'Tessera' was found suitable for cultivation under greenhouse conditions while soil application of aqueous solution of HA @ 1.5 g L-1 substantially resulted in higher production of quality tomato fruits.


Resumo Respostas de três híbridos de tomate (Lycopersicon esculentum Mill.) viz. 'Luanova', 'Savarona' e 'Tessera' para várias doses (0, 0,5, 1,0, 1,5 e 2,0 g L-1) de aplicação de ácido húmico (AH) no solo foram avaliadas em termos de crescimento da planta, produtividade e qualidade de frutas, em casa de vegetação, durante 2011-12 e 2012-13. Além das características de qualidade melhoradas, valores mais elevados para o rendimento e os componentes do rendimento foram registrados para frutos de tomate colhidos de plantas do cultivar 'Tessera' em comparação com aqueles colhidos de outros híbridos testados, independentemente das estações de cultivo. As plantas do cultivar 'Luanova', no entanto, frutificaram mais cedo com maior número de frutos por planta. A aplicação de AH no solo apresentou efeitos positivos sobre a produtividade e a qualidade físico-química dos frutos de tomate, independentemente da dose de AH e do cultivar investigado, nas duas safras. A aplicação de HA no solo na dose maior de 1,5 g L-1 apresentou melhores resultados nos três cultivares de tomate testados, quanto ao crescimento vegetativo e reprodutivo, e melhorou significativamente a qualidade físico-química dos frutos. Conclusivamente, o híbrido de tomate 'Tessera' foi considerado adequado para cultivo em casa de vegetação, enquanto a aplicação no solo de solução aquosa de HA @ 1,5 g L-1 resultou substancialmente em maior produção de frutos de tomate de qualidade.

8.
Braz. j. biol ; 84: e268551, 2024. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1430009

RESUMO

The present work was to study the genetic variability between the major carps Labeo rohita and Cirrhinus mrigala and their hybrids of L. rohita (male♂) and C. mrigala (female♀). Genetic variability was studied by employing RAPD molecular markers. 25 samples of each target species having different sizes with the same age group for the determination of interspecific variation were collected. The morphometric parameters such as body weight, total length, tail length, and lengths of dorsal and anal fins of each individual were recorded and results showed that wet body weight, total length, dorsal fin, anal fin, and tail fin length are positively correlated and then the DNA was extracted using the inorganic salt-based method and conformed by Gel electrophoresis. Twenty-four arbitrary decamer primers were used to get species-specific RAPD analysis Distinct and highly reproducible RAPD profiles with significant genetic variability was detected among species. Only five primers showed amplification. The RAPAD primer OPB-05 produced a total of seven bands out of these 5 monomorphic and 2 polymorphic, so in this case, the percentage polymorphism was 28.57%. The Hybrid show more than a 50% difference from the Labeo rohita. This shows that the Hybrid more resembles C.mrigala. Phylogenetic analysis demonstrated that hybrid (L. rohita ♂ X Cirrhinus mrigala ♀) is the closest to C. mrigala and the farthest from L. rohita. Overall data are presented concerning the applications of RAPD markers for hybrid identification, genetic diversity assessment, and studying taxonomic relationships at a molecular level.


O presente trabalho teve como objetivo estudar a variabilidade genética entre as carpas maiores Labeo rohita e Cirrhinus mrigala e seus híbridos de L. rohita (machos) e C. mrigala (fêmeas). A variabilidade genética foi estudada empregando marcadores moleculares RAPD. 25 amostras de cada espécie-alvo com tamanhos diferentes e com a mesma faixa etária foram coletadas para a determinação da variação interespecífica. Os parâmetros morfométricos como peso corporal, comprimento total, comprimento da cauda e comprimento das nadadeiras dorsal e anal de cada indivíduo foram registrados. O DNA foi extraído através do método à base de sal inorgânico e conformado por eletroforese em gel. 24 primers decâmeros arbitrários foram usados ​​para obter a análise RAPD espécie-específica. Perfis RAPD distintos e altamente reprodutíveis com significativa variabilidade genética foram detectados entre as espécies. Apenas 5 primers apresentaram amplificação. O primer RAPAD OPB-05 produziu um total de 7 bandas, dessas, 5 monomórficas e 2 polimórficas, portanto, neste caso, o percentual de polimorfismo foi de 28,57%. O Hybrid mostrou mais de 50% de diferença do Labeo rohita. Isso mostra que o híbrido se parece mais com o C.mrigala. A análise filogenética demonstrou que o híbrido (L. rohita macho X Cirrhinus mrigala fêmea) é o mais próximo de C. mrigala e o mais distante de L. rohita. Foram apresentados dados relativos à aplicação de marcadores RAPD para identificação de híbridos, avaliação de diversidade genética e estudo de relações taxonômicas ao nível molecular.


Assuntos
Variação Genética , Carpas/genética
9.
Ciênc. rural (Online) ; 54(3): e20220538, 2024. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1513996

RESUMO

ABSTRACT: Flora of Türkiye is hosting many Origanum sp. and spp. valuable members of Lamiaceae, including outstanding endemic species and hybrids. Those are having a number of using field and still meeting the World's major demand. Five combinations of artificial Oregano hybrids were cultivated in Ankara ecological conditions. Among those species; Origanum minutiflorum and Origanum onites are endemic to the flora of Türkiye and the combinations of those hybrids are very valuable and unique. According to the field studies results; the highest green herb yield was provided from H4 as 439.93g and from H5 as 317.26 g x plant-1. H2 and H3 showed the highest green leaf yield by 278.69 and 244.33 g x plant-1, and the highest leaf ratio (%). The essential oils ranged between 4.20% and 5.96%, Carvacrol predominated in the hybrids at; 77.90% (H1), 61.26% (H3) and 26.99% (H4), 72.09 (H5), and linalool at 45.86% (H2).


RESUMO: A flora da Turquia hospeda muitos Origanum sp. e spp. membros importantes de Lamiaceae, incluindo espécies endêmicas excepcionais e híbridos. Cinco várias combinações de híbridos artificiais de orégano foram cultivadas em condições ecológicas de Ancara. Entre essas espécies, Origanum minutiflorum e Origanum onites são endêmicos da flora Turca e as combinações desses híbridos são muito valiosas e únicas. De acordo com os resultados dos estudos de campo, a maior produção de erva verde foi obtida do H4 com 439,93g e do H5 com 317,26 g x planta-1. H2 e H3 apresentaram a maior produção de folhas verdes em 278,69 e 244,33 g x planta-1. Os óleos essenciais variaram entre 4,20% e 5,96%. O carvacrol predominou nos híbridos 77,90% (H1), 61,26% (H3) e 26,99% (H4), 72,09 (H5), e linalol a 45,86% (H2).

10.
Plants (Basel) ; 12(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38068686

RESUMO

The simultaneous analysis of the maximum number of chemical elements present in plant tissues provides more comprehensive information about their chemical constitution and increases the number of characteristics for the selection process in various plant breeding programs. The objective of this study was to analyze productivity, grain yield, and concentration of chemical elements in tissues of Coffea canephora clones to study phenotypic diversity and estimate genetic parameters for use in breeding. This experiment was carried out in Manaus, Amazonas, Brazil, in randomized blocks with four replications. The concentrations of elements in various organs were quantified using total reflection X-ray fluorescence (TXRF). Genetic parameters and genetic divergence were estimated, and genotypes were clustered using the UPGMA hierarchical method and non-metric multidimensional scaling analysis. The study allowed us to differentiate the performance of the clones in terms of the absorption of essential and non-essential chemical elements for plant development and to analyze the correlation of the characteristics in the selection process. TXRF efficiently characterizes the presence and concentration of multiple elements, aiding genotype discrimination for C. canephora improvement.

11.
Future Microbiol ; 18: 1225-1233, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37882752

RESUMO

Aim: To evaluate antifungal potential of 5,6,7,8-tetrahydroimidazo[1,2-a]pyrazine hybrids based on thiosemicarbazones and thiazolidinediones against pathogenic Sporothrix species. Methods: Antifungal activity of nine compounds were assessed by broth microdilution. Interactions between active compounds and itraconazole were evaluated by the checkerboard assay using non-wild-type isolates. Cytotoxicity of the compounds was determined. Results: Four C-3 substituted analogs showed antifungal activity, unrelated to thiosemicarbazone or thiazolidinedione functions. Synergistic interactions between the four compounds and itraconazole, and low toxicity on mouse fibroblast cells were observed. Activity of 5,6,7,8-tetrahydroimidazo[1,2-a]pyrazine hybrids against Sporothrix depended on the substitution on the imidazopyrazine ring. Conclusion: Antifungal potential, overcoming itraconazole resistance and low toxicity indicate the possible use of that series of compounds in a therapeutic alternative for treatment of sporotrichosis.


Assuntos
Sporothrix , Tiazolidinedionas , Tiossemicarbazonas , Animais , Camundongos , Antifúngicos/farmacologia , Itraconazol/farmacologia , Tiossemicarbazonas/farmacologia , Testes de Sensibilidade Microbiana
12.
Food Res Int ; 173(Pt 2): 113393, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803731

RESUMO

In Brazil, after the witch's broom disease incidence, diverse cocoa hybrids were developed, and variations were reported on their composition and characteristics. Based on this, the present study aimed to evaluate the pulp composition of several cocoa hybrids in order to better understand these variations. Results show that cocoa pulp is composed, on average, of 76 % sugar, and a wide variation (20 %) was observed in sugar content between hybrids. Regarding the sugar profile, a prevalence of reducing sugars was observed. Pod origin also plays an important role in pulp composition, with variations between hybrids from Espírito Santo and Bahia states. In relation to the degree of ripeness, ripe pods showed higher fructose and glucose content, while unripe pods presented mainly sucrose. Similar to sugars, the cello-oligossacharides profile was influenced by the degree of pod ripeness and origin and most ripe samples presented mainly cellobiose, cellotriose and cellotetrose. In addition, the prebiotic potential of cocoa pulp was highlighted by cello-oligossacharides digestion assay which exhibited low rates of degradation. Varying enzymatic activity was observed amongst different pulp hybrids, with polyphenol oxidase showing a higher variation when compared to invertase and polygalacturonase ranging. This study shows that the pod hybrid, origin and ripening degree may change the cocoa pulp composition. Therefore, it is very important to understand and evaluate these variations, in order to obtain better results in pulp utilization either in cocoa fermentation or as a coproduct.


Assuntos
Cacau , Chocolate , Cacau/metabolismo , Açúcares/metabolismo , Fermentação , Glucose/metabolismo
13.
Am J Bot ; 110(11): e16242, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37681637

RESUMO

PREMISE: Cultivated species and their wild relatives often hybridize in the wild, and the hybrids can survive and reproduce in some environments. However, it is unclear whether cultivar alleles are permanently incorporated into the wild genomes or whether they are purged by natural selection. This question is key to accurately assessing the risk of escape and spread of cultivar genes into wild populations. METHODS: We used genomic data and population genomic methods to study hybridization and introgression between cultivated and wild carrot (Daucus carota) in the United States. We used single nucleotide polymorphisms (SNPs) obtained via genotyping by sequencing for 450 wild individuals from 29 wild georeferenced populations in seven states and 144 cultivars from the United States, Europe, and Asia. RESULTS: Cultivated and wild carrot formed two genetically differentiated groups, and evidence of crop-wild admixture was detected in several but not all wild carrot populations in the United States. Two regions were identified where cultivar alleles were present in wild carrots: California and Nantucket Island (Massachusetts). Surprisingly, there was no evidence of introgression in some populations with a long-known history of sympatry with the crop, suggesting that post-hybridization barriers might prevent introgression in some areas. CONCLUSIONS: Our results provide support for the introgression and long-term persistence of cultivar alleles in wild carrots populations. We thus anticipate that the release of genetically engineered (GE) cultivars would lead to the introduction and spread of GE alleles in wild carrot populations.


Assuntos
Daucus carota , Humanos , Estados Unidos , Daucus carota/genética , Alelos , Polimorfismo de Nucleotídeo Único/genética , Hibridização Genética , Massachusetts
14.
J Biol Inorg Chem ; 28(8): 711-723, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37768364

RESUMO

In this work, two analogous coumarin-thio and semicarbazone hybrid compounds were prepared and evaluated as a potential antichagasic agents. Furthermore, palladium and platinum complexes with the thiosemicarbazone derivative as ligand (L1) were obtained in order to establish the effect of metal complexation on the antiparasitic activity. All compounds were fully characterized both in solution and in solid state including the resolution of the crystal structure of the palladium complex by X-ray diffraction methods. Unexpectedly, all experimental and theoretical characterizations in the solid state, demonstrated that the obtained palladium and platinum complexes are structurally different: [PdCl(L1)] and [PtCl2(HL1)]. All the studied compounds lower the proliferation of the amastigote form of Trypanosoma cruzi while some of them also have an effect on the trypomastigote stage. Additionally, the compounds inhibit T. cruzi release from host cells in variable extents. The Pd compound presented a remarkable profile in all the in vitro experiments, and it showed no toxicity for mammalian cells in the assayed concentrations. In this sense, in vivo experiments were performed for this compound using an acute model of Chagas disease. Results showed that the complex significantly lowered the parasite count in the mice blood with no significant toxicity.


Assuntos
Tiossemicarbazonas , Tripanossomicidas , Trypanosoma cruzi , Animais , Camundongos , Paládio/farmacologia , Paládio/química , Tiossemicarbazonas/farmacologia , Tiossemicarbazonas/química , Ligantes , Parasitemia , Platina/química , Tripanossomicidas/farmacologia , Cumarínicos/farmacologia , Mamíferos
15.
Braz. dent. j ; Braz. dent. j;34(4): 127-134, July-Aug. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1520330

RESUMO

Abstract This in vitro study synthesized hybrid nanofibers embedded in graphene oxide (GO) and incorporated them into experimental resin composite monomers to evaluate their physical-mechanical properties. Inorganic-organic hybrid nanofibers were produced with precursor solutions of 1% wt. GO-filled Poly (d,l-lactide, PLA) fibers and scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) characterized the morphology and chemical composition of the spun fibers. Resin composite monomers were developed and a total of 5% nanofibers were incorporated into the experimental materials. Three groups were developed: G1 (control resin monomers), G2 (resin monomers/PLA nanofibers), and G3 (resin monomers/inorganic-organic hybrid nanofibers). Contact angle (n=3), flexural strength (n=22), elastic modulus (n=22), and Knoop hardness (n=6) were evaluated. The mean of the three indentations was obtained for each sample. The normality of data was assessed by QQ Plot with simulated envelopes and analyzed by Welch's method (p<0.05). Overall, SEM images showed the regular shape of nanofibers but were non-aligned. Compositional analysis from EDS (n=6) revealed the presence of carbon and oxygen (present in GO composition) and Si from the functionalization process. The results of contact angle (°) and hardness (Kg/mm2) for each group were as follow, respectively: G1 (59.65±2.90; 37.48±1.86a), G2 (67.99±3.93; 50.56±1.03b) and G3 (62.52±7.40; 67.83±1.01c). The group G3 showed the highest Knoop hardness values (67.83 kg/mm2), and the flexural strength of all groups was adversely affected. The experimental resin composite composed of hybrid nanofibers with GO presented increased hardness values and hydrophilic behavior.


Resumo Este estudo in vitro sintetizou nanofibras híbridas embebidas em óxido de grafeno (GO), incorporando-as à uma resina composta experimental de monômeros para avaliar suas propriedades físico-mecânicas. Nanofibras híbridas inorgânica-orgânicas foram produzidas com soluções precursoras de fibras poli (d, l-lactídeo, PLA) preenchidas com GO a 1% em peso e microscopia eletrônica de varredura (MEV) e espectroscopia de raio-X de energia dispersiva (EDS) caracterizaram a morfologia e composição química das fibras. Monômeros de resina composta foram desenvolvidos e um total de 5% de nanofibras foi incorporado aos materiais experimentais. Três grupos foram desenvolvidos: G1 (monômeros de resina controle), G2 (monômeros de resina/ nanofibras de PLA) e G3 (monômeros de resina/nanofibras híbridas inorgânico-orgânicas). Ângulo de contato (n=3), resistência à flexão (n=22), módulo de elasticidade (n=22) e dureza Knoop (n=6) foram avaliados. A média das três endentações foi obtida para cada amostra. A normalidade dos dados foi avaliada pelo QQ Plot com envelopes simulados e analisada pelo método de Welch (p<0,05). No geral, as imagens de MEV mostraram forma regular de nanofibras, mas não alinhadas. A análise composicional de EDS (n=6) revelou a presença de carbono e oxigênio (presentes na composição do GO) e Si resultante do processo de funcionalização. Os resultados do ângulo de contato (°) e dureza (Kg/mm2) para cada grupo foram os seguintes, respectivamente: G1 (59,65±2,90; 37,48±1,86a), G2 (67,99±3,93; 50,56±1,03b) e G3 (62,52±7,40; 67,83±1,01c). G3 apresentou os maiores valores de dureza Knoop (67,83 kg/mm2), e a resistência à flexão de todos os grupos foi prejudicada. A resina composta experimental composta por nanofibras híbridas com GO apresentou maiores valores de dureza e comportamento hidrofílico.

16.
Front Plant Sci ; 14: 1203972, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465392

RESUMO

Low rainfall rates are becoming increasingly frequent because of climate change, causing droughts and threatening world food security. For popcorn, drought is the most limiting abiotic factor for plant's growth and development. Thus, the water deficit directly impacts for crop productivity. Based on knowledge of the genetic basis of traits involved in stages of popcorn germination and seedling development under water stress, genotypes with potential for adaptation to adverse growing conditions can be selected early. Therefore, data on genetic effects and combining ability of 10 popcorn parents were compiled to propose breeding strategies for the development of cultivars with greater adaptation to water stress in the early stages. Forty-five diallel hybrids were evaluated under two different water regimes, that is, water stress and full irrigation. This corresponded to a water retention capacity of 25% and 70% of the germination paper. The plants were watered daily as needed for seven days. A range of factors were evaluated, that is, germination traits including the germination speed index and germination on the seventh day; shoot traits including length and dry weight; and root system including length, dry weight, root-to-shoot ratio, maximum root number, root network area, specific and root network length, and root volume. Breeding for drought adaption in the early stages of popcorn development can be successful when hybrids are used, because of the genetic effects of dominance (ϕs). These control the traits evaluated at the seedling stage. The combinations L61 x P2 and L71 x P3 were recommended, in view of the more successful performance estimated for traits related to the shoot and root system.

17.
Front Nutr ; 10: 1183935, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485394

RESUMO

In the scientific literature there are different analyses of the nutritional profiles of maize tortillas, whether they are landraces or hybrid maize versus those made with dry masa flour (DMF). In general terms, there is agreement in the reported content of moisture. However, for the other nutrients, a great disparity is reported for each type of tortilla which may be due to various factors such as the type of maize or processing methods. In this study, the nutritional aspects of maize tortillas made with different genotypes (five hybrids, two varieties, five landraces, six hybrid mixtures and six dry masa flours) under controlled conditions, were compared. More than 30 characteristics were analyzed. High performance hybrids and varieties (HPHV) and landraces had the highest (p < 0.05) antioxidant capacity (58.8% free, 150.2% bound). In terms of vitamins contents, the tortillas produced from DMF contained 11.2 and 3.5 times more B1, 18.6 and 7.8 times more B2, and 2.7 and 5.3 times more B3 than HPHV and landraces respectively; and only in these samples was detected folic acid. DMF tortilla samples contained 1.75 times more sodium and 2.75 times more iron than the other groups, and 0.75 times less calcium than HPHV. Zinc was present in higher concentration (p < 0.05) in DMF tortilla samples. The landraces had the highest protein content (average 10.28%), but the tortillas produced from DMF presented the highest protein quality evaluated by protein digestibility-corrected amino acid score (PDCAAS) (p < 0.05) that represents 27, 25 and 19% more than hybrids mixture, HPHV and landraces, respectively. This work gives valuable information on how different types of grains differ in the nutritional quality affecting the final product to provide more elements in the decision-making of processors. There is no a perfect maize, but there are genotypes that can be combined as mixtures and the processing method to design superior nutritional tortillas and related products for populations that highly consume them and improve their human health.

18.
Med Mycol ; 61(7)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37336574

RESUMO

Cryptococcus neoformans and C. gattii species complexes (phylum: Basidiomycota) are environmental yeasts and are the main cause of human cryptococcosis worldwide. The most recent molecular typing studies in Latin America have focused on the intertropical region. Thus, this study aimed to update the knowledge of human cryptococcosis in the South American temperate region. We obtained and analyzed 116 C. neoformans/C. gattii species complexes isolates from the Public Health Surveillance Laboratory between 2008-2013 and 2017-2021 (C. gattii species complex = 1 and C. neoformans species complex = 115). The average patient age was 45 years, with an overall male:female ratio of 3.1:1. The proportion of HIV-negative patients was significantly higher in the second study period. Restriction fragment length polymorphism typing of URA5 gene revealed that the C. neoformans species complex comprised 75.7% VNI, 2.6% VNII, 0.9% VNIII, 1.7% VNIV, 17.4% VNII/VNIV hybrids, and one C. neoformans isolate (0.9%) misidentified as VGI; the C. gattii species complex isolates comprised one VGII. The overall case fatality rate was 49.5%, with no differences in lethality between VNI and hybrid isolates. Of the four isolates responsible for episodes of reoccurrence, only one had a genotype different from the first episode. Antifungal susceptibility testing revealed that most isolates fell below the local epidemiological cut-off value. This study provides additional information for the analysis of C. neoformans/C. gattii species complexes dynamics in the South American temperate region.


This study describes the epidemiological and molecular trends of human cryptococcosis according to the public health Uruguayan surveillance network. The findings provide additional information for analyzing the Cryptococcusneoformans/C. gattii species complexes in the South American temperate region.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Masculino , Feminino , Animais , Antifúngicos/farmacologia , Uruguai/epidemiologia , Criptococose/epidemiologia , Criptococose/microbiologia , Criptococose/veterinária , Tipagem Molecular/veterinária , Genótipo , Técnicas de Tipagem Micológica/veterinária
19.
Pharmaceuticals (Basel) ; 16(6)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37375827

RESUMO

Alzheimer's Disease (AD) is a neurodegenerative condition characterized by progressive memory loss and other affected cognitive functions. Pharmacological therapy of AD relies on inhibitors of the enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), offering only a palliative effect and being incapable of stopping or reversing the neurodegenerative process. However, recent studies have shown that inhibiting the enzyme ß-secretase 1 (BACE-1) may be able to stop neurodegeneration, making it a promising target. Considering these three enzymatic targets, it becomes feasible to apply computational techniques to guide the identification and planning of molecules capable of binding to all of them. After virtually screening 2119 molecules from a library, 13 hybrids were built and further screened by triple pharmacophoric model, molecular docking, and molecular dynamics (t = 200 ns). The selected hybrid G meets all stereo-electronic requirements to bind to AChE, BChE, and BACE-1 and offers a promising structure for future synthesis, enzymatic testing, and validation.

20.
Pharmaceutics ; 15(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37242716

RESUMO

The application of mesenchymal stem cells (MSC) in bone tissue regeneration can have unpredictable results due to the low survival of cells in the process since the lack of oxygen and nutrients promotes metabolic stress. Therefore, in this work, polymeric membranes formed by organic-inorganic hybrid materials called ureasil-polyether for modified glucose release were developed in order to overcome the problems posed by a of lack of this nutrient. Thus, membranes formed by polymeric blend of polypropylene oxide (PPO4000) and polyethylene oxide (PEO500) with 6% glucose incorporation were developed. Physical-chemical characterization techniques were performed, as well as tests that evaluated thermal properties, bioactivity, swelling, and release in SBF solution. The results of the swelling test showed an increase in membrane mass correlated with an increase in the concentration of ureasil-PEO500 in the polymeric blends. The membranes showed adequate resistance when subjected to the application of a high compression force (15 N). X-ray diffraction (XRD) evidenced peaks corresponding to orthorhombic crystalline organization, but the absence of glucose-related peaks showed characteristics of the amorphous regions of hybrid materials, likely due to solubilization. Thermogravimetry (TG) and differential scanning calorimetry (DSC) analyses showed that the thermal events attributed to glucose and hybrid materials were similar to that seen in the literature, however when glucose was incorporated into the PEO500, an increase in rigidity occurs. In PPO400, and in the blends of both materials, there was a slight decrease in Tg values. The smaller contact angle for the ureasil-PEO500 membrane revealed the more hydrophilic character of the material compared to other membranes. The membranes showed bioactivity and hemocompatibility in vitro. The in vitro release test revealed that it is possible to control the release rate of glucose and the kinetic analysis revealed a release mechanism characteristic of anomalous transport kinetics. Thus, we can conclude that ureasil-polyether membranes have great potential to be used as a glucose release system, and their future application has the potential to optimize the bone regeneration process.

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