31 research outputs found
A new method for the direct tracking of in vivo lignin nanocapsules in Eragrostis tef (Poaceae) tissues
Ultrastructure of traumatic resin duct formation in Cupressus sempervirens L. in response to the attack of the fungus Seiridium cardinale (Wag.) Sutton & Gibson
Histochemical observations in Piper malgassicum (Piperaceae) with a special focus on the epidermis
This is the first contribution about the histochemistry of vegetative and reproductive aerial organs in the genus Piper L. Piper malgassicum accumulates alkaloids and terpenes in the epidermis and the underlying layers of parenchyma, both in the leaves, in the stems and in anthers. Some idioblasts appear to contain a large amount of secondary metabolites. The micro-anatomical analysis showed peculiar secretory structures both in the leaves, in the anthers and in the ovary. Several lipid aggregates, alkaloid droplets and calcium oxalate crystals were observed in leaves and stems, indicating their role in defence strategies, mechanical support, and pollinators attraction. In the anthers, we observed elaioplasts whose content suggest an alternative and indirect function in pollination and defence against micro-organisms. Besides, some lipid aggregates surrounded by microtubules, detected in the anthers, were recognized as lipotubuloids. The tapetum was of secretory type. Alkaloids and terpenes were widely distributed in the plant confirming the important biological role of this type of biomolecules and its functional range. In the anthers, terpene and polyphenol inclusions appeared particularly abundant in the epidermal layer, whereas calcium oxalate crystals were observed close to the ovule in the ovary at maturity
Conjunctivally Applied BDNF Protects Photoreceptors from Light-Induced Damage
Purpose: To test whether the topical eye treatment with BDNF prevents the effects of
continuous light exposure (LE) in the albino rat retina.
Methods: Two groups of albino rats were used. The first group of rats received an
intraocular injection of BDNF (2 lL, 1 lg/lL) before LE, while the second group was
treated with one single drop of BDNF (10 lL, 12 lg/lL) dissolved in different types of
solutions (physiological solution, the polysaccharide fraction of Tamarind gum, TSP,
and sodium carboxy methyl cellulose), at the level of conjunctival fornix before LE. The
level of BDNF in the retina and optic nerve was determined by enzyme-linked
immunosorbent assay. We recorded the flash electroretinogram (fERG) in dark
adapted rats 1 week after LE. At the end of the recording session, the retinas were
removed and labeled so that the number of photoreceptors nuclear rows and
thickness of the outer nuclear layer was analyzed.
Results: Intravitreal injection of BDNF before LE prevented fERG impairment. Different
ophthalmic preparations were used for topical eye application; the TSP resulted the
most suitable vehicle to increase BDNF level in the retina and optic nerve. Topical eye
application with BDNF/TSP before LE partially preserved both fERG response and
photoreceptors.
Conclusions: Topical eye treatment with BDNF represents a suitable, noninvasive tool
to increase the retinal content of BDNF up to a level capable of exerting
neuroprotection toward photoreceptors injured by prolonged LE.
Translational Relevance: A collyrium containing BDNF may serve as an effective,
clinically translational treatment against retinal degeneration
Endophytic Bacteria Associated with Origanum heracleoticum L. (Lamiaceae) Seeds
Seed-associated microbiota are believed to play a crucial role in seed germination, seedling establishment, and plant growth and fitness stimulation, due to the vertical transmission of a core microbiota from seeds to the next generations. It might be hypothesized that medicinal and aromatic plants could use the seeds as vectors to vertically transfer beneficial endophytes, providing plants with metabolic pathways that could influence phytochemicals production. Here, we investigated the localization, the structure and the composition of the bacterial endophytic population that resides in Origanum heracleoticum L. seeds. Endocellular bacteria, surrounded by a wall, were localized close to the aleurone layer when using light and transmission electron microscopy. From surface-sterilized seeds, cultivable endophytes were isolated and characterized through RAPD analysis and 16S RNA gene sequencing, which revealed the existence of a high degree of biodiversity at the strain level and the predominance of the genus Pseudomonas. Most of the isolates grew in the presence of six selected antibiotics and were able to inhibit the growth of clinical and environmental strains that belong to the Burkholderia cepacia complex. The endophytes production of antimicrobial compounds could suggest their involvement in plant secondary metabolites production and might pave the way to endophytes exploitation in the pharmaceutical field