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1.
Micron ; 183: 103647, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38759451

RESUMO

Pollen morphology and nutlet structures of some Prunella L. taxa were examined in detail by light microscopy (LM) and scanning electron (SEM) microscopy. Pollen grains of Prunella vary in size from small to large (Polar axis (P) = 22.25-66.04 µm, Equatorial diameter (E) = 17.56-75.64 µm). The shape of pollen grains are suboblate to prolate (P/E = 0.78-1.75) and the aperture structure is hexacolpate with granular membranes in apocolpium. Examinations of exine ornamentation show that pollen grains were recognized as bireticulate ornamentation with varying characteristics of the primary muri and secondary reticulum and four subtypes were identified. Nutlet measurements of four taxa were taken and their surfaces were examined by using SEM. While pollen ornamentations are represented by different characters among taxa, it has been concluded that nutlet surfaces do not have distinctive characters among investigated taxa. Pollen morphology of 7 taxa of Prunella has been investigated in detail for the first time.


Assuntos
Microscopia Eletrônica de Varredura , Pólen , Pólen/ultraestrutura , Microscopia Eletrônica de Varredura/métodos , Microscopia/métodos , Prunella/ultraestrutura , Prunella/anatomia & histologia
2.
Enzyme Microb Technol ; 142: 109676, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33220864

RESUMO

In this study, polymer-ceramic nanocomposites and/or composites were prepared by solution removal method using poly(methylmethacrylat) (PMMA) and nano-hydroxyapatite (nHA). They were characterized using X-ray diffraction (XRD), Fourier transform infrared-attenuated total reflection spectroscopy (FTIR-ATR), and differential thermal analysis/thermogravimetry (DTA/TG). Their effects and biocompatibilities on antioxidant enzymes were also investigated in detail. It has been shown that nHA was dramatically dispersed at nanoscale in the polymer matrix. The interaction occurred between OH groups of nHA and carbonyl groups of polymer and introduction of ceramic into the polymer matrix generally resulted in an increase in thermal stability. Nanocomposites and composites had different effects on enzyme activities. Samples synthesized in acetone increased enzyme activities for glutathione reductase (GR) and glucose-6 phosphate dehydrogenase (G6PD) enzymes, while inhibiting glutathione peroxidase (GPx) and catalase (CAT) enzyme activities. On the other hand, samples synthesized in tetrahydrofuran (THF) exhibited inhibitory behavior for G6PD and CAT enzymes. The samples synthesized in different media did not show any regularity on enzyme activities. The nanocomposites and/or composites prepared in acetone media were better hemocompatible than those in THF.


Assuntos
Durapatita , Nanocompostos , Antioxidantes , Polimetil Metacrilato , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
3.
PhytoKeys ; 134: 83-96, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31686955

RESUMO

Nepeta viscida and N. nuda subsp. nuda and N. × tmolea were examined in this study. Mainly fresh leaf pieces, dried with silica grains, were used for DNA extraction procedures via DNA isolation kits. Standard PCR techniques were executed using three different primer sets (one nuclear DNA region (nrITS) and two chloroplast DNA regions (rpl32-trnL and trnA(Leu)-trnA(Phe)-trnL-F). DNA sequences were analysed and evaluated using different molecular approaches and software. Consequently, the inconstant molecular structure and hybrid nature of N. × tmolea specimens were shown and interpreted in this study. According to our result, N. × tmolea have some intermediate characters compared to its parents. nrITS data give more information phylogenetically, and also the most polymorphic loci are seen in nrITS data. Morphological and molecular data contribute to define separation of N. × tmolea. Consequently, the inconstant molecular structure and hybrid nature of N. × tmolea specimens were shown and interpreted in this study.

4.
PhytoKeys ; (96): 63-77, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29670454

RESUMO

Teucrium alyssifolium Stapf (endemic), Teucrium pestalozzae Boiss. (endemic) and Teucrium brevifolium Schreb. are three closely related taxa in Teucrium sect. Teucrium. The obtained data from the anatomical studies revealed that these three taxa represent the general anatomical characteristics of the Lamiaceae family. Leaves, anatomical features such as thick cuticle, abundant trichomes, rich palisade parenchyma layer in the mesophyll provide evidence that these three species are xeromorphic structures. Leaf and stem anatomy showed that the taxa have generally similar anatomical features. However, cuticle layers, epidermis cells size, indumentum density, mesophyll types, palisade parenchyma occupied in the mesophyll, presence of spherocrystals in leaves and parenchyma, collenchyma and sclerenchyma layers in stems show differences amongst the taxa. Anatomical characters of leaf and stem of these taxa are examined for the first time in this study.

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