Pea root responses under naproxen stress: changes in the formation of structural barriers in the primary root in context with changes of auxin and abscisic acid levels.

Pharmaceuticals belong to pseudo-persistent pollutants because of constant entry into the environment and hazardous potential for non-target organisms, including plants, in which they can influence biochemical and physiological processes. Detailed analysis of results obtained by microscopic observations using fluorescent dyes (berberine hemisulphate, Fluorol Yellow 088), detection of phytohormone levels (radioimmunoassay, enzyme-linked immune sorbent assay) and thermogravimetric analysis of lignin content proved that the drug naproxen (NPX) can stimulate the formation of root structural barriers. In the primary root of plants treated with 0.

Silicon triggers sorghum root enzyme activities and inhibits the root cell colonization by Alternaria alternata.

Silicon inhibits the growth of Alternaria alternata into sorghum root cells by maintaining their integrity through stimulating biochemical defense reactions rather than by silica-based physical barrier creation. Although the ameliorating effect of silicon (Si) on plant resistance against fungal pathogens has been proven, the mechanism of its action needs to be better understood on a cellular level. The present study explores the effect of Si application in sorghum roots infected with fungus Alternaria alternata under controlled in vitro conditions.

Alleviation mechanisms of metal(loid) stress in plants by silicon: a review.

Silicon (Si), although not considered as an essential element for plants in general, can ameliorate the phytotoxicity induced by excess metal(loid)s whether non-essential (e.g. Cd, Pb, Cr, Al, As, and Sb) or essential (e.

Silicification of Root Tissues.

Silicon (Si) is not considered an essential element, however, its tissue concentration can exceed that of many essential elements in several evolutionary distant plant species. Roots take up Si using Si transporters and then translocate it to aboveground organs. In some plant species, root tissues are also places where a high accumulation of Si can be found.

Cellulose fibrils formation and organisation of cytoskeleton during encystment are essential for Acanthamoeba cyst wall architecture.

Acanthamoebae success as human pathogens is largely due to the highly resistant cysts which represent a crucial problem in treatment of Acanthamoeba infections. Hence, the study of cyst wall composition and encystment play an important role in finding new therapeutic strategies. For the first time, we detected high activity of cytoskeletal elements - microtubular networks and filamentous actin, in late phases of encystment.

Root hair abundance impacts cadmium accumulation in Arabidopsis thaliana shoots.

Background And Aims: Root hairs increase the contact area of roots with soil and thereby enhance the capacity for solute uptake. The strict hair/non-hair pattern of Arabidopsis thaliana can change with nutrient deficiency or exposure to toxic elements, which modify root hair density. The effects of root hair density on cadmium (Cd) accumulation in shoots of arabidopsis genotypes with altered root hair development and patterning were studied.

Formation of silica aggregates in sorghum root endodermis is predetermined by cell wall architecture and development.

Background And Aims: Deposition of silica in plant cell walls improves their mechanical properties and helps plants to withstand various stress conditions. Its mechanism is still not understood and silica-cell wall interactions are elusive. The objective of this study was to investigate the effect of silica deposition on the development and structure of sorghum root endodermis and to identify the cell wall components involved in silicification.

Asymmetrical development of root endodermis and exodermis in reaction to abiotic stresses.

Background and Aims In the present study, we show that development of endodermis and exodermis is sensitively regulated by water accessibility. As cadmium (Cd) is known to induce xeromorphic effects in plants, maize roots were exposed also to Cd to understand the developmental process of suberin lamella deposition in response to a local Cd source. Methods In a first experiment, maize roots were cultivated in vitro and unilaterally exposed to water-containing medium from one side and to air from the other.

Clinical Recognition of Melanoma in Dermatologists and Nondermatologists.

Background: The incidence of melanoma is increasing annually in Canada.

Objectives: This retrospective study was designed to assess the ability of physicians of different specialties to accurately recognize melanoma.

Methods: Pathology reports of biopsies submitted to Vancouver Coastal Health with clinical diagnoses of melanoma were reviewed (January to July 2013).

The effect of cadmium-nickel interactions on superoxide production, cell viability and membrane potential (EM) in roots of two maize cultivars.

Effects of CdCl2, NiCl2 or both on superoxide production, viability and membrane potential (EM) of root cells in meristematic (MZ) and differentiation (DZ) zones of two maize cultivars (cv. Premia and cv. Blitz) were studied.

Cadmium translocation by contractile roots differs from that in regular, non-contractile roots.

Background And Aims: Contractile roots are known and studied mainly in connection with the process of shrinkage of their basal parts, which acts to pull the shoot of the plant deeper into the ground. Previous studies have shown that the specific structure of these roots results in more intensive water uptake at the base, which is in contrast to regular root types. The purpose of this study was to find out whether the basal parts of contractile roots are also more active in translocation of cadmium to the shoot.

New method for visualization of silica phytoliths in Sorghum bicolor roots by fluorescence microscopy revealed silicate concentration-dependent phytolith formation.

Silica phytoliths are microscopic structures of amorphous hydrated silica (SiO2 · nH2O) formed by specialized plant cells. Besides their biological roles, physical, chemical, and structural properties of biogenic silica offer a wide spectrum of applications in many fields of industry and technology. Therefore, processes involved in their formation recently become a very interesting topic to study.

Cadmium uptake, localization and stress-induced morphogenic response in the fern Pteris vittata.

Cadmium uptake, tissue localization and structural changes induced at cellular level are essential to understand Cd tolerance in plants. In this study we have exposed plants of Pteris vittata to different concentrations of CdCl2 (0, 30, 60, 100 μM) to evaluate the tolerance of the fern to cadmium. Cadmium content determination and its histochemical localization showed that P.

Plant growth regulators enhance gold uptake in Brassica juncea.

The use of plant growth regulators is well established and they are used in many fields of plant science for enhancing growth. Brassica juncea plants were treated with 2.5, 5.

Endodermal cell-cell contact is required for the spatial control of Casparian band development in Arabidopsis thaliana.

Background And Aims: Apoplasmic barriers in plants fulfil important roles such as the control of apoplasmic movement of substances and the protection against invasion of pathogens. The aim of this study was to describe the development of apoplasmic barriers (Casparian bands and suberin lamellae) in endodermal cells of Arabidopsis thaliana primary root and during lateral root initiation.

Methods: Modifications of the endodermal cell walls in roots of wild-type Landsberg erecta (Ler) and mutants with defective endodermal development - scarecrow-3 (scr-3) and shortroot (shr) - of A.

An easy method for cutting and fluorescent staining of thin roots.

Background And Aims: Cutting plant material is essential for observing internal structures and may be difficult for various reasons. Most fixation agents such as aldehydes, as well as embedding resins, do not allow subsequent use of fluorescent staining and make material too soft to make good-quality hand-sections. Moreover, cutting thin roots can be very difficult and time consuming.

Elevated expression of Rad18 regulates melanoma cell proliferation.

The E3 ligase Rad18 is a key regulator for the lesion bypass pathway, which plays an important role in genomic stability. However, the status of Rad18 expression in melanoma is not known. Using melanoma tissue microarray (TMA), we showed that nuclear Rad18 expression was upregulated in primary and metastatic melanoma compared to dysplastic nevi.

Cadmium induces hypodermal periderm formation in the roots of the monocotyledonous medicinal plant Merwilla plumbea.

Background And Aims: Merwilla plumbea is an important African medicinal plant. As the plants grow in soils contaminated with metals from mining activities, the danger of human intoxication exists. An experiment with plants exposed to cadmium (Cd) was performed to investigate the response of M.

Root responses to cadmium in the rhizosphere: a review.

This article reviews the responses of plant roots to elevated rhizosphere cadmium (Cd) concentrations. Cadmium enters plants from the soil solution. It traverses the root through symplasmic or apoplasmic pathways before entering the xylem and being translocated to the shoot.