Insight into Fucoidan-Based PEGylated PLGA Nanoparticles Encapsulating Methyl Anthranilic Acid: In Vitro Evaluation and In Vivo Anti-Inflammatory Study

A potential fucoidan-based PEGylated PLGA nanoparticles (NPs) offering a proper delivery of N-methyl anthranilic acid (MA, a model of hydrophobic anti-inflammatory drug) have been developed via the formation of fucoidan aqueous coating surrounding PEGylated PLGA NPs. The optimum formulation (FuP2) composed of fucoidan:m-PEG-PLGA (1:0.5 w/w) with particle size (365 ± 20.76 nm), zeta potential (−22.30 ± 2.56 mV), % entrapment efficiency (85.45 ± 7.41), drug loading (51.36 ± 4.75 µg/mg of NPs), % initial burst (47.91 ± 5.89), and % cumulative release (102.79 ± 6.89) has been further investigated for the anti-inflammatory in vivo study. This effect of FuP2 was assessed in rats’ carrageenan-induced acute inflammation model. The average weight of the paw edema was significantly lowered (p ≤ 0.05) by treatment with FuP2. Moreover, cyclooxygenase-2 and tumor necrosis factor-alpha immunostaining were decreased in FuP2 treated group compared to the other groups. The levels of prostaglandin E2, nitric oxide, and malondialdehyde were significantly reduced (p ≤ 0.05) in the FuP2-treated group. A significant reduction (p ≤ 0.05) in the expression of interleukins (IL-1β and IL-6) with an improvement of the histological findings of the paw tissues was observed in the FuP2-treated group. Thus, fucoidan-based PEGylated PLGA–MA NPs are a promising anti-inflammatory delivery system that can be applied for other similar drugs potentiating their pharmacological and pharmacokinetic properties.     

Aligning fisheries management with life history in two commercially important groupers in Chuuk,Federated States of Micronesia

1. Camouflage grouper, Epinephelus polyphekadion (Bleeker, 1849), and squaretail coralgrouper, Plectropomus areolatus (Rüppell, 1830), are commercially important medium-bodied groupers that aggregate at specific sites and times to spawn and are highly vulnerable to fishing during these events. Populations of both species are in decline globally, such that management specifically targeting these species is warranted.
2. A 12-month fish market survey in Chuuk, Federated States of Micronesia, provided an opportunity to examine age-based reproductive life history of these two groupers and assess whether current management acts to conserve them. Life history characteristics of both E. polyphekadion and P. areolatus include a functionally gonochoristic sexual pattern and rapid growth particularly during early life history.
3. P. areolatus demonstrated early maturity (2.8 years) and a relatively brief lifespan (10 years), while delayed maturity (4.5 years) and higher longevity (25 years) was shown for E. polyphekadion. The spawning seasons for E. polyphekadion and P. areolatus were 2 and 3 months, respectively, which fall entirely within the January–April grouper sales, catch, and export ban period for Chuuk. Marketed catch included 22% E. polyphekadion and 15% P. areolatus juveniles, suggesting that size limits may aid in the conservation of these species.
4. Findings from this and recent grouper life history studies suggest that the current 4-month ban in Chuuk be applied only to grouper species known to reproduce during these months to minimize economic impacts to fishers and market owners, and prevent shifts in fishing pressure to more vulnerable species, such as those with low population turnover times, slow growth, or late maturity. Size limits for catch, sale and export are also warranted as an additional management option.

     

Feline B7.1 and B7.2 proteins produced from swinepox virus vectors are natively processed and biologically active: potential for use as nonchemical adjuvants

Costimulatory ligands, B7.1 and B7.2, have been incorporated into viral and DNA vectors as potential nonchemical adjuvants to enhance CTL and humoral immune responses against viral pathogens. In addition, soluble B7 proteins, minus their transmembrane and cytoplasmic domains, have been shown to block the down regulation of T-cell activation through blockade of B7/CTLA-4 interactions in mouse tumor models. Recently, we developed swinepox virus (SPV) vectors for delivery of feline leukemia antigens for vaccine use in cats [Winslow, B.J., Cochran, M.D., Holzenburg, A., Sun, J., Junker, D.E., Collisson, E.W., 2003. Replication and expression of a swinepox virus vector delivering feline leukemia virus Gag and Env to cell lines of swine and feline origin. Virus Res. 98, 1-15]. To explore the use of feline B7.1 and B7.2 ligands as nonchemical adjuvants, SPV vectors containing full-length feline B7.1 and B7.2 ligands were constructed and analyzed. Full-length feline B7.1 and B7.2 produced from SPV vectors were natively processed and costimulated Jurkat cells to produce IL-2, in vitro. In addition, we explored the feasibility of utilizing SPV as a novel expression vector to produce soluble forms of feline B7.1 (sB7.1) and B7.2 (sB7.2) in tissue culture. The transmembrane and cytoplasmic regions of the B7.1 and B7.2 genes were replaced with a poly-histidine tag and purified via a two-step chromatography procedure. Receptor binding and costimulation activity was measured. Although feline sB7.1-his and sB7.2-his proteins bound to the human homolog receptors, CTLA-4 and CD28, both soluble ligands possessed greater affinity for CTLA-4, compared to CD28. However, both retained the ability to partially block CD28-mediated costimulation in vitro. Results from these studies establish the use of SPV as a mammalian expression vector and suggest that full-length-vectored and purified soluble feline B7 ligands may be valuable, nonchemical immune-modulators.     

The role of oxidative stress in spring barley cross-adaptation to different heavy metals

The aim of this study is to investigate the possibilities and the mechanisms of spring barley (Hordeum vulgare L.) cross-adaptation to different heavy metals after hardening with ozone (O₃), drought and UV-B radiation. Dry shoot biomass, accumulation of superoxide (O₂˙^?) and malondialdehyde (MDA), and activities of enzymes superoxide dismutase (SOD), glutathione reductase (GR) and catalase (CAT) were measured after hardening and heavy metal treatments. Seedlings, exposed to ozone and drought prior to copper (Cu) treatment, showed significantly increased tolerance to this heavy metal. The most possible causes of cross-adaptation to this redox-active heavy metal, which triggered very strong oxidative stress in nonhardened barley seedlings, were increased CAT activity, mitigation of O₂˙^? accumulation and lipid peroxidation. Cross-adaptation to cadmium (Cd) was induced only by drought hardening. In this case, however, adaptation had lower effect on antioxidative enzymes, did not altered O₂˙^? accumulation and even slightly increased the intensity of lipid peroxidation. The study reveals that stimulation of CAT activity and mitigation of oxidative stress are the main reasons for plant adaptation to Cu; whereas cross-adaptation to Cd, heavy metal with much lower oxidative capacity, is determined by the mechanisms that are not related to oxidative stress directly.     

Plant root morphology and soil biological indicators under primary development of various swards

Plant nutrition conditions are limited in naturally acidic soil due to harmful hydrogen and aluminium ions. More favourable conditions for plant nutrition (soil liming) will affect root qualitative and quantitative parameters and influence ecosystem stability. Four legume–grass swards were cultivated. The swards were a combination of one species of legume and two species of grasses: Trifolium pratense L., Trifolium repens L., Trifolium hybridum L., Medicago sativa L. (each of 50%) with Phleum pratense L. (35%) and Poa pratensis L. (15%). The aim of this study is to evaluate the root morphological and soil biological indicators of legume–grass swards under the first two years of development in soils with different pH levels.

Sward ecosystem development depends on the pH of the soil, sward species composition and soil biota. During the first year of sward development, soil pH had a significant influence on the morphology of root system. Sward‘s root mass and total root length was 2.4 and 2.2 times bigger in naturally acidic soil. This resulted in a change of biological parameters.

In the second year of sward development, soil pH had no significant influence on sward‘s root mass. However, under the impact of different soil pH, various sward‘s root systems were formed and the root C:N ratio had changed. It is observed that, regardless of the sward species composition and the year of development, at higher root C:N ratio soil microbial biomass was higher and CO₂ emissions were lower in swards in naturally acidic soils.

Regardless of soil pH, different types of clover–grass swards promoted organic carbon immobilization in microbial biomass and, at the same time, stabilized the sward ecosystem in the top soil layer (soil respiration in 0–10 and 10–20?cm layers was lower) more effectively than the alfalfa–grass sward.     

The effects of agrogenic transformation on soil profile morphology,organic carbon and physico-chemical properties in Retisols of Western Lithuania

The aim of this study was to determine changes in the morphological, physical and chemical properties of Retisols caused by their agrogenic transformation. The study carried out on Retisols on relatively natural and agrogenically affected land in 2016. Soil samples taken from the genetic horizons of all profiles to measure soil organic carbon, pH, hydromorphic and physical properties. Due to long-term, deep ploughing, the sequence of soil horizons in the Retisol profile had changed from O–Ah–El–ElBt to Ahp–ElBt. Intensive soil liming changed chemical properties and morphological features of Retisol. The clay and silt particles leached out of from the Ah and El horizons to the deeper layers due to illuviation and podsolization. The content of SOC in the 0–30 cm layer of the Ah horizon of agrogenically affected Retisol was 1.0%, and in the forest Retisol – 1.7%; however, forest Retisol was more acidic. Ploughing and no tillage management caused a reduction in total porosity, water holding capacity and plant available water content compared with the other land-uses. We conclude that the use of ploughless tillage on Retisol is not identical to the conditions of natural soil formation and soil fertility maintenance.     

European and United States perspectives on forest operations in environmentally sensitive areas

This paper offers a forest operations perspective in environmentally sensitive areas in Europe and the United States. The objective is to help inform key sustainability knowledge gaps in forest operations to reduce impacts on the environment and the equipment operators in these increasingly targeted and difficult to operate in areas. Under existing guidelines and best management practices, the protection of ecosystem services linked to soil, water, wildlife and biodiversity have rightly received the highest considerations. However, the connection between protecting these ecological values, safe operational practices and technological advancements is rarely well articulated. One means to address the operational and technological gap is the selection of equipment and tailor the work conditions to terrain type, forest features and management objectives. To that effect, this paper discusses the environmental, planning, equipment selection and operator considerations and proposes possible solutions and guidelines to contain both the operators’ safety and environmental risks in forest operations.