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1.
Microsc Res Tech ; 87(10): 2253-2265, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38729775

RESUMEN

The Pteridaceae family, known for its taxonomic complexity, presents challenges in identification due to high variability among its species. This study investigates the spore morphology employing both SEM and LM techniques in 10 Pteridaceae taxa phytogeographicaly Sino-Himalayan, Malesian, and European elements in Pakistan. The taxa include Adiantum capillus-veneris, A. incisum, A. venustum, Aleuritopteris bicolor, Oeosporangium nitidulum, O. pteridioides, Onychium cryptogrammoides, O. vermae, Pteris cretica, and P. vittata. The objective is to assess their taxonomic relevance and develop a spore-based taxonomic key. Findings indicate differences in spore shape, sizes, exospore thickness, and in surface ornamentation highlighting the potential for taxonomic differentiation. Spores are trilete, and notable differences are observed in the dimension of spores in both distal and proximal sides. Equatorial dimensions vary between 35 and 50 µm, while the polar diameter ranges from 29 to 50 µm. SEM revealed different spore ornamentation types that show several useful characteristics establishing valuable taxonomic variations. The studied Adiantum taxa feature a perispore with tubercules and a micro-granulose surface. The spores of examined Oeosporangium and Aleuritopteris taxa shows cristate sculptures with variable ornamentations. Both species of Onychium have tuberculate-pleated tubercles with sinuous folds on both distal and proximal sides. The surface ornamentation among examined Pteris taxa show variability. PCA analysis indicated that spore quantitative data identified distinct groups, underscoring taxonomic significance. Nevertheless, there was variation observed in surface ornamentation and spore shape, indicating the potential for discrimination among taxa. RESEARCH HIGHLIGHTS: Spore morphology of 10 Pteridaceae taxa has been investigated through LM and SEM. Investigated species shows differences in spore shape, sizes, exospore thickness, and in surface ornamentation. Ornamentation on the perispore provides several valuable characteristics, establishing useful taxonomic distinctions. Spore morphological analysis is effective at the generic level, with minor distinctions discernible at the species level.


Asunto(s)
Microscopía Electrónica de Rastreo , Pteridaceae , Esporas , Esporas/ultraestructura , Pteridaceae/anatomía & histología , Pteridaceae/clasificación , Pakistán , Microscopía
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124339, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38696995

RESUMEN

The FDA (Food and Drug Administration, (USA)) lists ZnO as a material that is widely acknowledged to be safe. ZnO NPs with a range of tiny particle sizes were made using the precipitation process. ZnO nanoparticles' surface is embellished with a tripodal sensor containing naphthol units. The assembly with the same receptor decorated on ZnO NPs is contrasted with the cation detection capabilities of the purified tripodal receptor. The UV-visible spectrophotometric analysis was conducted to study the state transitions of the receptor and the decorated ZnO receptor. A positive selectivity to Al3+ cations is determined by the fluorescence study under ideal circumstances. The particle size and surface morphologies are determined by DLS and SEM analysis for the same receptor - TP1 and embellished with a tripodal receptor TP2. Using a fluorescence switch-on Photoinduced Electron Transfer (PET) mechanism, the receptor coated on ZnO detects the presence of Al3+ ions with specificity. The binding constant value was determined using the B-H plot equation. Binding stoichiometry for [TP1-Al3+, TP2-Al3+] showed a 1:1 ratio. The fluorescence switches ON-OFF process of the ZnO surface adorned - TP2 with Tripodal receptor- TP1 was used to create molecular logic gates, which can function as a module for sensors and molecular switches. The addition of Na2EDTA in the solution of the [TP1; TP2 - Al3+] complex resulted in a noticeable reduction in the emission of fluorescence. This finding offers compelling support for the reversibility of the chemosensor. To enable the practical application of this sensor, we have developed a cassette containing receptors TP1 and TP2. Successfully, it can detect Al3+ metal ions. We performed a comprehensive assessment of the dependability and appropriateness of our approach in measuring the concentration of Al3+ ions in wastewater produced by important industrial procedures.

3.
Curr Biol ; 34(4): 755-768.e4, 2024 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-38272029

RESUMEN

During the process of flower opening, most petals move downward in the direction of the pedicel (i.e., epinastic movement). In most Delphinium flowers, however, their two lateral petals display a very peculiar movement, the mirrored helical rotation, which requires the twist of the petal stalk. However, in some lineages, their lateral petals also exhibit asymmetric bending that increases the degree of mirrored helical rotation, facilitating the formation of a 3D final shape. Notably, petal asymmetric bending is a novel trait that has not been noticed yet, so its morphological nature, developmental process, and molecular mechanisms remain largely unknown. Here, by using D. anthriscifolium as a model, we determined that petal asymmetric bending was caused by the localized expansion of cell width, accompanied by the specialized array of cell wall nano-structure, on the adaxial epidermis. Digital gene analyses, gene expression, and functional studies revealed that a class I homeodomain-leucine zipper family transcription factor gene, DeanLATE MERISTEM IDENTITY1 (DeanLMI1), contributes to petal asymmetric bending; knockdown of it led to the formation of explanate 2D petals. Specifically, DeanLMI1 promotes cell expansion in width and influences the arrangement of cell wall nano-structure on the localized adaxial epidermis. These results not only provide a comprehensive portrait of petal asymmetric bending for the first time but also shed some new insights into the mechanisms of flower opening and helical movement in plants.


Asunto(s)
Delphinium , Ranunculaceae , Ranunculaceae/metabolismo , Delphinium/metabolismo , Factores de Transcripción/metabolismo , Flores/anatomía & histología , Regulación de la Expresión Génica de las Plantas
4.
Microsc Res Tech ; 86(11): 1496-1509, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37341239

RESUMEN

The seed morphology of 40 taxa within the genus Hypericum (Hypericaceae) from China, representing 9 sections of the genus, was examined using both Light and Scanning Electron Microscopy to evaluate the taxonomic relevance of macro- and micro-morphological features. Details articulating variation in seed size, color, shape, appendages, and seed coat ornamentation are described, illustrated, and compared, and their taxonomic importance is discussed. Seeds were generally brown in color and cylindric-ellipsoid to prolonged cylindric in shape. Seed size displayed wide variation, ranging from 0.37-1.91 mm in length and 0.12-0.75 mm in width. Seed appendages were observed as a characteristic morphological feature. Seed surface ornamentation has high phenotypic plasticity, and four types (reticulate, foveolate, papillose, and ribbed) can be recognized. In general, seed color and shape have limited taxonomic significance. However, some other features represent informative characters that can be used efficiently in distinguishing the studied taxa at the section and/or species levels. The findings illustrate that considerable taxonomic knowledge can be obtained by investigating the seed features of Hypericum, and the use of Scanning Electron Microscopy can reveal inconspicuous morphological affinities among species and play a role in taxonomic and systematic studies of the genus Hypericum. RESEARCH HIGHLIGHTS: Macro- and micro-morphological features of seeds of 40 Hypericum taxa from China were examined using Light and Scanning Electron Microscopy, providing the first broad study regarding seed morphology for Hypericum from China. Details and variations of seed size, shape, color, surface ornamentation, and appendages are fully presented. Seed features and their variation have important taxonomic significance at the section and/or species levels within Hypericum.


Asunto(s)
Clusiaceae , Hypericum , Microscopía Electrónica de Rastreo , Semillas/anatomía & histología , China
5.
Microsc Res Tech ; 85(2): 641-666, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34585806

RESUMEN

The present investigation aims to determine pappus and fruit characters of 21 taxa representing 12 different genera from Turkey. For this reason, present data of pappus and cypsela characters as well as previous results from 21 additional Cardueae taxa have been comparatively evaluated, and a total of 42 taxa were grouped by using cluster and MDS analysis methods. The cluster analysis resolved two main clusters, with five taxa having scale or coroniform pappus as the first-branching group. Considerable variations were observed in the surface sculpture, and the pericarp and testa anatomical structures as well as the pappus characteristics. On the basis of fruit surface sculpture, four major types and two subtypes of ornamentation patterns were discerned, and based on their anatomies three types of testa epidermal structure were recognized. Our results show that Centaurea s.l. taxa do not exhibit clear distinction from the genus level; in some cases the taxa are separated to some extent, in other cases they are combined with Cyanus and Psephellus taxa. Two Klasea species with sclerenchymatous mesocarp exhibit the closest relationship to Centaurea s.l. taxa. Rhaponticum repens displays the nearest neighborhood with Centaurea s.l. and Klasea taxa. A diagnostic key based on the examined characteristics has been given. The taxonomic importance and systematic implications of the results are discussed in the light of the current framework. The evaluated cypsela and pappus characters are useful not only in assessing relationships within this group but also in delimiting genera and species.


Asunto(s)
Asteraceae , Frutas , Microscopía Electrónica de Rastreo , Filogenia , Turquía
6.
Microsc Res Tech ; 84(12): 3128-3149, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34292653

RESUMEN

The scale morphology of a native goby, Awaous jayakari (Gobiidae) was studied using scanning electron microscopy and light microscopy. The morphological descriptions were based on the scale's type, shape, and features of the anterior, posterior, and lateral fields. Further characteristics of the focus, circuli, radii, lepidonts, and cteni, were investigated. Morphometric indices were calculated for some scales. Shape variability of scales was high in different regions. However, the majority of scales displayed a polygonal shape (hexagonal and pentagonal). Both ctenoid and cycloid scales were observed in the studied fishes. The ctenoid scale of A. jayakari was peripheral and characterized by the presence of one row of marginally located spines in two completed and uncompleted subtypes. The focus was positioned posteriorly or postero-centrally. The microscopic examinations revealed the presence of lepidonts of different sizes being very tiny, small, or prominent performing flat, blunt, pointed, short, or truncated shapes. The rostral margin of the scales was convex to moderately flattened and represented striate, scalloped, or waved types. Lateral fields were often flattened in all regions, while convex in the lateral fields of the scales of some individuals. The posterior field showed variations in different regions, for example, tapered and flattened ends. The anterior-posterior axis presented a laterally expanded or an elongated extension. The considerable morphological variation in the scales of various body regions makes it difficult to nominate a typical scale to be used in taxonomic studies. However, the key scales can be used for the comparison of different Awaous species.


Asunto(s)
Perciformes , Animales , Peces , Humanos , Microscopía Electrónica de Rastreo
7.
Microsc Res Tech ; 84(11): 2749-2773, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34121269

RESUMEN

The scale morphology of nine Mullidae taxa consisting of three genera and nine species from the Persian Gulf and the Gulf of Oman was described and compared using light and scanning electron microscopy from four different body regions. The general scale type in the studied mullid species was ctenoid except in the head region of Mulloidichthys vanicolensis and Parupeneus margaritatus, which had cycloid scales. The scales demonstrated a large focus with the central or centro-posterior position. The large variations of scale morphology were observed for the scales from different body regions of a single species. The shape of focus was in five types with the round type being the most common. In the scales of most examined species, there were 5-6 radii present in the anterior field. No radii exist in the lateral and posterior fields, and the radii orientation was parallel in all the studied species. The rostral margin of scales represented five types among the studied species; waved (M. vanicolensis), smooth in (P. rubescens), dentate (Upeneus doriae), scalloped (U. vittatus), and fluted (U. tragula). The lepidont shape varied among the species from blunt to flat, pointed, tiny, sharp, pointed, triangle, short, and long. The results also showed that the relative scale size has a desirable contribution to separate the examined genera. The scale morphological-based tree was largely consistent with the known systematics of the studied fishes. It was concluded that variation of scale characters has probably taxonomic and even phylogenetic information in both species and genus levels in the studied mullid fishes. However, variation of scale morphology between body regions, as shown in this study, suggests that scale characters should be used cautiously for taxonomic studies of these fishes.


Asunto(s)
Electrones , Perciformes , Animales , Peces , Microscopía Electrónica de Rastreo , Filogenia
8.
Microsc Res Tech ; 84(2): 180-191, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32888243

RESUMEN

The normal and lateral line scales from above the head and four flank regions were investigated in two goatfishes by using light microscopy to evaluate the microscopic characteristics of scale surface ornamentation from different body parts of these fishes and to add new morphological data for their discrimination. The body scales were removed and digital images captured with a Dino-Lite digital camera connected to a Leica compound microscope. The presence of both transverse and longitudinal radii was a distinctive characteristic for the scales of studied goatfishes. The most distinctive features of the key scales discriminating the two goatfishes were the scale shape, the presence of irregular grooves in scale surface, the presence of transverse radii in the lateral fields, and the availability of lepidont at the anterior field. The lateral line scale ornamentations were almost similar in two species; however, the lateral line canal was branching in Parupeneus heptacanthus. Scale extension index indicated that in both species, the dimension of normal key scales tends to the right, while the dimension of lateral line scales tends to the left. This study accentuated that scales from different body regions may exhibit variation in surface ornamentations, that scale morphology could successfully be used to discriminate the examined goatfishes, and that the use of fish scale microscopy is an easy and relatively rapid method and does not require fish sacrifice. Since fish identification is essential for the conservation and management of species, the use of scale morphology to this purpose appears particularly promising.


Asunto(s)
Escamas de Animales , Microscopía , Perciformes , Escamas de Animales/anatomía & histología , Animales , Perciformes/anatomía & histología
9.
Microsc Res Tech ; 82(8): 1326-1333, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31087738

RESUMEN

Spore morphology of Thelypteridaceae species growing in Malakand Division, Northern Pakistan, was studied using both light microscopy and scanning electron microscopy. The taxa are Christella dentata and Glaphyropteridopsis erubescens in the subfamily Thelypteridoideae, and Phegopteris connectilis, Pseudophegopteris pyrrhorhachis, and Pseudophegopteris levingei in the subfamily Phegopteridoideae. The studied species exhibit differences in spore size, exospore thickness, color, and ornamentation. Spores of the studied species are monolete and medium-sized, and shape is ellipsoidal in both polar and equatorial views. The average measurement of the polar diameter ranges from 27 µm to 31 µm, whereas in the equatorial direction it varied from 20 µm to 40 µm. The exospore thickness ranges from 1.2 µm to 2.4 µm. Reticulate, laevigate with microgranules, cristate, and coarsely echinate surface ornamentation are observed among the species. Multivariate analysis including unweighted pair group method with arithmetic mean and principal component analysis was used for the grouping and discrimination of species and genera.


Asunto(s)
Helechos/clasificación , Esporas/ultraestructura , Microscopía , Microscopía Electrónica de Rastreo , Análisis Multivariante , Pakistán
10.
Microsc Res Tech ; 82(2): 114-121, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30575188

RESUMEN

Current research carried out in Pakistan is the first report on spermoderm ornamentation of eight species of tribe Acacieae (Mimosoidae) by using scanning electron microscopic techniques representing two genera, Fedherbia and Acacia were examined. Different spermoderm ornamentation were observed, described and discussed for their taxonomic importance. Seeds surfaces of the studied tribe possess novel variations in macro and micro morphology. Great variations were observed in both qualitative and quantitative characters of seeds. Seeds shape was oblong, ovate to elliptical and spermoderm ornamentation was levigate, rugose, polygonal and discoid, colliculate, and papillose type. These variations in the spermoderm ornamentation can be used as an aid in identification and classification of the members of tribe Acacieae.


Asunto(s)
Acacia/anatomía & histología , Acacia/ultraestructura , Variación Biológica Poblacional , Semillas/anatomía & histología , Semillas/ultraestructura , Acacia/clasificación , Microscopía Electrónica de Rastreo , Pakistán , Semillas/clasificación
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