Protoplasma最新文献

The genus Senecio, which is a basal angiosperm group, holds significant importance for evolutionary and phylogenetic research. It is notable for possessing male meiotic characteristics that are rarely observed in most angiosperms. However, the current understanding about male meiosis in Senecio remains incomplete. Here, we traced the cell morphological characteristics of microsporogenesis, and male gametophyte development of Senecio cannabifolius was observed by transmission electron microscopy. The results showed that the microspore mother cells were surrounded by callose; the cytokinesis was simultaneous; the tetrad was tetrahedral; and the mature pollen was two-celled pollen with three germination pores. During the meiosis of microspore mother cells, there were abundant organelles in the cytoplasm at leptotene stage. Obvious and clear synaptonemal complex was found in pachytene stage. In the prophase I stage, the number of organelles in the cytoplasm decreased; the cristae of mitochondria decreased; and the electron density of plastids was low. It began to recover at the metaphase I and formed an obvious organelle band in the anaphase I, which separated the two daughter nuclei and contained abundant organelles. During this period, the organelles in the cytoplasm changed regularly, which was the phenomenon of cytoplasmic reorganization. The pollen wall was formed at the late uninucleate stage; the pollen wall was mature at the binucleate microspore stage; and the pollen has abortion phenomenon. These results for the first time revealed the ultrastructure of microspores and male gametophytes during the development of S. cannabifolius and enriched the understanding of the formation of pollen grains by microspores in Compositae plants.

Desmids are valuable bioindicators in peatland ecosystems due to their sensitivity to environmental changes. In temperate and boreal wetlands, seasonal desiccation of aquatic habitats, which is increasing in frequency and severity due to ongoing climate change, is currently considered a key factor structuring the distribution of individual taxa. In this study, the desiccation tolerance of Micrasterias thomasiana and Staurastrum hirsutum isolated from contrasting hydrological environments in the peatland habitats of the Ore Mountains, Czech Republic, is investigated. Using controlled experimental conditions, we subjected both young, actively growing and old, mature cultures to four different desiccation treatments and evaluated morphology and photosynthetic performance. Our results showed that young and old cultures of both species exhibited a very similar photophysiological response. Severe desiccation led to an irreversible decline in the effective quantum yield of photosystem II in both species, resulting in cell death. Mild drought stress allowed the cultures to recover, indicating that the stress severity determines the recovery potential. Finally, prolonged desiccation resulted in irreversible damage in older cultures of both species, emphasizing the limited desiccation resilience of desmids. We observed similarities in morphology with Zygnema "pre-akinetes," but in contrast to these resilient cells, the old cells of M. thomasiana and S. hirsutum did not survive the harsher desiccation conditions. Long-term mild desiccation revealed a higher resistance of S. hirsutum, probably due to the protective role of its dense mucilage. In nature, these two species usually inhabit localities with low desiccation risk or avoid and mitigate desiccation stress through localized survival strategies.

Eriococcid-induced galls exhibit many unusual features, such as sexual dimorphism and differences in life cycle duration, which are reflected in the morphology, anatomy, and metabolism of female- and male-induced galls. These sex-based distinctions between the galls result from differential developmental processes related to the time female and male insects remain inside the gall, their feeding activity, and the degree of stress imposed on the host plant cellular machinery. We assessed the immunocytochemical and Raman spectroscopy profiles of two host plant-gall inducer systems: Annona dolabripetala (Annonaceae)-Pseudotectococccus rolliniae Hodgson and Gonçalves, and Pseudobombax grandiflorum (Malvaceae)-Eriogallococcus isaias Hodgson and Magalhães. We expected differences in the dynamics of cell wall chemical components between male and female galls, with particular effects on gall structural and functional profiles, also regarding specific constraints in each system. The epitopes of xylogalacturonans and homogalacturonans, as well as their degree of methylesterification, are affected by the sex of the gall inducers, conferring a rigid structure to the cell walls of female-induced galls in comparison with those of the male-induced galls. Raman spectroscopy detected cellulose peaks in both female- and male-induced galls, with pronounced lignin bands in female-induced galls. The sex-based chemical distinctions between female- and male-induced galls imply in differences in terms of higher rigid cell walls in the female-induced galls, which was similar for both host plants.

The term "green synthesis" refers to the use of sustainable and environmentally friendly methods to produce materials, chemicals, or nanoparticles (NPs). This approach emphasizes the use of renewable resources, energy-efficient processes, and non-toxic chemicals to minimize environmental impact. In our study, we synthesized cerium oxide NPs (CeO₂ NPs) of varying crystal sizes using leaf extract from the Moringa oleifera plant and evaluated their effects on the photosynthetic and antioxidant properties of mustard (Brassica juncea L.). X-ray diffraction (XRD) analysis confirmed the successful synthesis of CeO₂ NPs, with average crystal sizes determined using the Debye-Scherrer equation as 4.5 nm, 8.5 nm, and 15.4 nm (designated as A, B, and C respectively). Fourier transform infrared spectroscopy (FTIR) analysis revealed stretching frequencies at 550 cm⁻¹, confirming the presence of Ce-O stretching bands and the use of natural compounds in the synthesis process. Scanning electron microscopy (SEM) analysis showed that the CeO₂ NPs were irregularly shaped and agglomerated, while transmission electron microscopy (TEM) analysis confirmed that the particles were spherical and polydisperse. Dynamic light scattering (DLS) and zeta potential analysis further confirmed the polydispersity and stability of synthesized NPs in solution. Following synthesis, the CeO₂ NPs were applied foliarly to mustard crops at concentrations of 50, 100, and 150 ppm. The results demonstrated that all concentrations of NPs enhanced growth, photosynthetic efficiency, and gaseous exchange parameters in mustard. Additionally, the NPs regulated balance between oxidation and reduction (redox) reactions in cell. It helps maintain cellular function by controlling reactive oxygen species (ROS) and antioxidants, preventing damage and ensuring normal metabolism. Notably, the 4.5 nm-sized NP (A) at a concentration of 100 ppm was the most effective in improving these parameters. CeO₂ NPs show promise as a sustainable alternative to traditional fertilizers and pesticides, contributing to more sustainable agricultural practices. This pioneering research highlights the potential of biogenically synthesized CeO₂ NPs in boosting crop performance, marking a significant advancement in agricultural nanotechnology.

Local healers in South Asia use Plumeria rubra Linn. leaves to treat various coagulation disorders in animals and humans. This study (in silico, in vitro, and in vivo) aimed to explore the pharmacological basis for the possible thrombolytic and anticlotting properties of the leaf extract of P. rubra. Phytoconstituents of P. rubra were dock against coagulation proteins: prothrombin, thromboplastin, and fibrin using in silico approach. Phytochemical screening, HPLC, and antioxidant, anticoagulant, and thrombolytic potential were evaluated using in vitro approach. Healthy male rabbits were divided into five groups (six rabbits each). Groups 1-3 were treated with aqueous-methanolic (30:70%) extract of P. rubra at 200, 300, and 600 mg/mL respectively groups in contrast to the positive and negative control groups. Thrombolytic activity was assessed at doses of 200, 300, and 600 µg/mL in comparison with standard urokinase (600 µg/kg). Platelet adhesion was evaluated at a dose of 200, 300, and 600 µg/mL against adrenaline (2 µM) and acute oral dose toxicity was assessed using in vivo approach. In silico study resulted in an excellent binding affinity and showed significant interaction with coagulation proteins. Phytochemical analysis showed a range of phytochemical classes: alkaloids, tannins, flavonoids, glycosides, anthraquinones, and saponins. HPLC analysis confirmed the phytoconstituents plumericin, rutin, kaempferol, and isoquercetin already reported for coagulation disorders. P. rubra showed excellent antioxidant potential and was assessed using DPPH, NO, and SOD assays. The activated partial thromboplastin time (APTT), bleeding time (BT), prothrombin time (PT), and clotting time (CT) all went up with increasing doses in the aqueous-methanolic extract (p ≤ 0.05). Comparing the plant extract to urokinase, the plant extract demonstrated considerable (p ≤ 0.05) clot lysis. Additionally, it dose-dependently delayed the ADR-induced platelet adhesion dose-dependently (p ≤ 0.05). The outcome of this study justifies its therapeutic utility in coagulation disorders and can be used as an alternative medicine.

We have analyzed by immunohistochemical methods the Oberhautchen-beta layer, here abbreviated as beta-layer, of lizards with hard scales and lizards with softer scales. Different antibodies for detecting Corneous Beta Proteins (CBPs) have been utilized. The agamid beta-corneous layer is generally 3-4 times thicker than in geckos, and the surface microornamentation forms a honeycomb pattern. Geckos feature thinner beta-layers and a spinulated pattern and show immunolocalization for CBPs and isopeptide bonds, a product of transglutaminase catalysis, in their thin beta-layer. CBPs and isopeptide-bonds are detected in the superficial Oberhautchen and alpha-layer of agamids while the beta-layer is immuno-negative. Considering the limitations of immunolabeling methods, the unexpected result might derive from inaccessibility of antibodies to epitopes that are masked within the packed corneous material of the agamid beta-layer. However, bioinformatics analysis for CBPs sequenced in the few species of agamids so far known indicates that these proteins have low identity with those of other lizards. This suggests that agamids possess peculiar CBPs but low isopeptide bonds in their inflexible beta-layer. In contrast, the thinner and pliable beta-corneous layers of geckos may derive from the presence of isopeptide bonds mixed with lower amounts of CBPs. The differences in material properties of lizard scales, inflexibility versus pliability, are adaptive for the different ecological conditions of the species here analyzed.

This study analyzed the morphoanatomical, histochemical, and molecular characteristics of three Cannabis sativa strains, CAT1, CAT2, and CAT3, acronyms for Argentine therapeutic strains in Spanish (Cepas Argentinas Terapéuticas), using bright light, fluorescence, and scanning electron microscopy. The strains were previously cultivated and chemically characterized at CIM, UNLP, CONICET. Five plants from each strain were collected at the end of the vegetative and flowering phases; part of the material was fixed for anatomical studies, and part was used fresh for histochemical analyses. Anatomical features of roots, stems, leaves, and flowers were analyzed, focusing on stomatal density, trichome types, and the presence of laticifers. Histochemical analyses detected phenolic compounds, cannabinoids, lipophilic compounds, and other metabolites using specific staining techniques. Additionally, short sequence repeat (SSR) molecular markers were employed to characterize and confirm the genomic identity of the strains. Morphoanatomical and histochemical traits enabled differentiation among the strains, revealing significant variations in leaflet dimensions, trichome density, and metabolic profiles. For example, CAT1 exhibited thicker leaves and larger stomata, CAT2 had a higher density of laticifers, and CAT3 showed a greater density of cannabinoid-rich glandular trichomes. Using SSR molecular markers, strain genomic identity was confirmed with a probability greater than 99.99999983%. This integrative approach, combining morphoanatomical, histochemical, and molecular analyses, highlights the unique features of CAT1, CAT2, and CAT3 and underscores the importance of molecular markers in validating strain identity.

Extant amphibians are divided into three distinct lineages: Gymnophiona, Urodela, and Anura. Owing to their diversity, they are widely used in research concerning, among others, tissue regeneration. Here, we describe larval myotomal myogenesis in the Chinese fire-bellied newt, Hypselotriton orientalis. Morphological, ultrastructural, cytochemical, and immunohistochemical analyses showed that trunk muscles grow through hypertrophy and hyperplasia mediated by the expression of typical myogenic factors, such as Pax7, from muscle progenitor cells. Our findings also suggest a third alternative mechanism for muscle growth involving the muscle splitting or fragmentation of preexisting larval myotubes.

In this study, using a pharmaceutical approach, we analyzed the NO accumulation and emission from the root tips of barley seedlings and the possible mechanisms of NO catabolism. Application of flavohemeprotein inhibitors, such as azide, cyanide, diphenyleneiodonium and dicumarol, an inhibitor of the plasma membrane electron transport chain, increased the NO level in root tissue and stimulated the NO emission from root tip cells. It can be concluded that barley root tips generate and, at the same time, consume a considerable amount of NO, probably by the plasma membrane flavohemeproteins. This high NO-consuming activity of barley root tips efficiently degraded even the externally applied high concentrations of NO without marked root growth inhibition. These results suggest that the root tip cells NO consumption activity plays an important role in the regulation of NO level in barley root tips.

Madhumukthi Kudineer Chooranum (MKC) is a decoction from polyherbal Siddha formulation for managing diabetes. The safety of this formulation has not been reported earlier. This study evaluates the chronic toxicity of the Siddha herbal formulation MKC in experimental Sprague-Dawley (SD) rats. In an acute oral toxicity study, male and female SD rats were orally administered a single dose of MKC (2000 mg/kg), and clinical signs and mortality stages were observed for 14 days along with weekly body weight. On day 15, the rats were euthanized and the gross morphology was carried out during necropsy. In a chronic (repeated dose) oral toxicity study, the male and female rats were orally administered MKC (200, 400, and 800 mg/kg) once daily for up to 180 days. MKC showed outstanding tolerance in SD rats with a NOAEL of 2000 mg/kg, with no adverse effects or death during the study. In acute and chronic toxicity trials, MKC did not alter parameters or cause harmful effects. No group died or became moribund in either study.