Therapeutic Potential of Marine Peptides in Prostate Cancer: Mechanistic Insights

Prostate cancer (PCa) is the leading cause of cancer death in men, and its treatment is commonly associated with severe adverse effects. Thus, new treatment modalities are required. In this context, natural compounds have been widely explored for their anti-PCa properties. Aquatic organisms contain numerous potential medications. Anticancer peptides are less toxic to normal cells and provide an efficacious treatment approach via multiple mechanisms, including altered cell viability, apoptosis, cell migration/invasion, suppression of angiogenesis and microtubule balance disturbances. This review sheds light on marine peptides as efficacious and safe therapeutic agents for PCa.     

What factors influence the stem taper of <Emphasis Type="Italic">Eucalyptus</Emphasis>: growth,environmental conditions,or genetics?

• Introduction   

Stem taper equations have been widely used for volume estimation to varied top diameter limits or for biomass calculations. However, their main drawback is that specific calibration is often necessary for each species or clone, and accounting for genetic and environmental effects is often a challenge.     

The successional status of sugar maple (Acer saccharum), revisited

Two complementary experimental designs at two contrasting scales (landscape/long term; individual tree/short term) were used for an in-depth evaluation of the successional status of sugar maple (AS: Acer saccharum Marsh.). First, forest disturbances during the 20th century and composition were mapped for two landscapes in the Du Lièvre watershed of southern Quebec. Our results show that, as well as dominating stands in the absence of fire, AS often rapidly developed dominance after fire, especially in the south of our study area. Similarly, a majority of AS-dominated stands clearcut in 1928 continued to be AS-dominated 60 years later. Second, we examined AS seedlings planted under two very contrasting light regimes. AS seedlings showed a combination of traits particularly adapted to tolerate shade under a low light regime. However, owing to a surprisingly high phenotypic plasticity, AS also exhibited efficient development under high light. This suggests the classification of AS as a late-successional species should indeed be revised and that generalist or trans-successional would be a more appropriate designation for this species. We discuss the ramifications of such a status revision, with an emphasis on the implications for its silviculture.     

Establishment,survivorship, and growth of yellow birch seedlings after site preparation treatments in large gaps

The occurrence of yellow birch (YB) in the northeastern forests of North America is a source of concern. Several guidelines suggest ways to favor the regeneration of this species, including creating openings from small gaps to large clearcuts, coupled or not with a variety of soil preparation treatments. However, it is not clear if soil preparation treatment favors YB establishment by simply increasing the availability of good seedbed types, or by also altering competition pressure exerted by interfering species during the period of seedling establishment. For this study, large gaps (900 m²) were created in a 70-year old YB dominated forest, to which three treatments differing in soil disturbance intensities were applied (i.e., soil scarification (i) using a rake [raking]; or (ii) by dragging slash out to the edges of the gap [slash drag]; and (iii) limited to the passage of the harvesting equipment [control]). The proportion of seedbed types reportedly most favorable for YB establishment (i.e., mineral-dominated) increased as the severity of the site preparation increased. The opposite was observed for organic-dominated seedbeds. As a result, the stocking of YB seedlings increased with the severity of site preparation. However, YB stocking was deemed sufficient in all gaps to ensure future canopy dominance, even in the control treatment. Although YB seedlings generally achieved greater heights as site preparation intensity increased, it was clear that this did not reflect vigorous growth as, on average, greater heights coincided with greater seedling height–diameter ratios. At the seedbed level, height–diameter ratio was associated with an increase in surrounding competition pressure and an increase in the incidence of stem apical death (SAD), which in turn decreased height differences among seedbed types by the end of the study. At the gap level, this blurred the advantages of site preparation over a laisser-faire strategy. The incidence of SAD was greatest in the slash drag and the rake treatments. Consequently, we cannot say that intense soil scarification is worth the expenses, especially in stands where YB seed sources are abundant.     

Morphological and physiological responses of beech (Fagus sylvatica) seedlings to grass-induced below ground competition

We examined morphological and physiological responses of beech (Fagus sylvatica L.) seedlings to grass-induced below ground competition in full-light conditions. Two-year-old beech seedlings were grown during two growing seasons in 160-l containers in bare soil or with a mixture of five grass species widely represented in semi-natural meadows of central France. At the end of the second growing season, beech seedlings in the presence of grass showed significant reductions in diameter and height growth, annual shoot elongation, and stem, root and leaf biomass, but an increase in root to shoot biomass ratio. Grasses greatly reduced soil water availability, which was positively correlated with daily seedling diameter increment. Beech seedlings seemed to respond to water deficit by anticipating stomatal closure. There was evidence of competition for nitrogen (N) by grasses, but its effect on seedling development could not be separated from that of competition for water. By labeling the plants with 15N, we showed that beech seedlings absorbed little N when grasses were present, whereas grasses took up more than 97% of the total N absorbed in the container. We conclude that, even if beech seedlings display morphological and physiological adaptation to below ground competition, their development in full-light conditions may be strongly restricted by competition from grass species.     

Charcoal affects early development and hormonal concentrations of somatic embryos of hybrid larch

Embryogenic tissue of hybrid larch (Larix x marschlinsii Coaz) was multiplied on Medium M (modified MSG medium supplemented with the plant growth regulators (PGRs) 2,4-dichlorophenoxyacetic acid (2,4-D; 9 microM) and N-6-benzyladenine (2.25 microM)). After 1 week, cultures were transferred to either MSG lacking PGRs (Medium C-) or MSG lacking PGRs but supplemented with 1% activated charcoal (Medium C+). Embryos were sampled after 1 week on Medium M, C- or C+. Embryos were analyzed by ELISA for abscisic acid (ABA), abscisic acid-glucose ester, 2,4-D, indole-3-acetic acid (IAA), indole-3-aspartate (IAAsp), zeatin (Z), zeatin riboside (ZR), isopentenyladenine (iP) and isopentenyladenosine (iPA). Transfer of embryos to Medium C+ reduced the embryo concentrations of 2,4-D and iPA, but resulted in elevated concentrations of IAA, IAAsp, ABA, Z, ZR and iP. Charcoal reduced 2,4-D concentrations of embryos by an order of magnitude greater than PGR-free medium alone. Charcoal affected embryo concentrations of five of the eight PGRs quantified. Use of either C+ or C- medium as part of the maturation protocols also affected germination and plantlet establishment of the embryos. A 1-week treatment on Medium C+ positively influenced plantlet establishment and generally reduced variability during both germination and plantlet establishment.     

Effect of heat treatment intensity on some conferred properties of different European softwood and hardwood species

Effect of heat treatment intensity on some conferred properties like elemental composition, durability, anti-swelling efficiency (ASE) and equilibrium moisture content (EMC) of different European softwood and hardwood species subjected to mild pyrolysis at 230 °C under nitrogen for different durations has been investigated. Independently of the wood species studied, elemental composition is strongly correlated with the mass losses due to thermal degradations which are directly connected to treatment intensity (duration). In all cases, an important increase in the carbon content associated with a decrease in the oxygen content was observed. Heat-treated specimens were exposed to several brown rot fungi, and the weight losses due to fungal degradation were determined after 16 weeks, while effect of wood extractives before and after thermal treatment was investigated on mycelium growth. ASE and EMC were also evaluated. Results indicated important correlations between treatment intensity and all of the wood conferred properties like its elemental composition, durability, ASE or EMC. These results clearly indicated that chemical modifications of wood cell wall polymers are directly responsible for wood decay durability improvement, but also for its improved dimensional stability as well as its reduced capability for water adsorption. All these modifications of wood properties appeared simultaneously and progressively with the increase in treatment intensity depending on treatment duration. At the same time, effect of extractives generated during thermal treatment on Poria placenta growth indicated that these latter ones have no beneficial effect on wood durability.     

Communicative Action to Level the Playing Field in Forest Plantations in Indonesia

The government of Indonesia allocated state land to private companies to establish forest plantations. However, ownership of this land was contested by some Sumatran communities. The plantation company, endorsed by the government, quickly developed a partnership to resolve the conflict, but this was unclear and inequitable. Action research was carried out to facilitate communication among stakeholders. This communicative action changed some perceptions and shared values began to emerge. A forum was established, which contributed to equitability producing a better partnership. This research is a model for empowering local communities in climate change, bioenergy, and food security negotiations.     

Variation of wood density and hydraulic properties of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) clones related to a heat and drought wave in France

Drought response of three Douglas-fir clones (slow, intermediate and fast growing) inhabiting two different climatic regimes in France was examined. We used the hydraulic conductivity and the percent loss of conductivity due to embolism from stems and branches as well as wood microdensity measurements to determine the role of genetics in the control of embolism in this species. Conductivity and tree-ring’s microdensity variables (ring width: RW, mean ring density: MRD, minimum ring density: MID and maximum ring density: MAD) were compared in growth rings in all three clones during a typical year (2002) vs. an extremely dry year (2003). A new method was developed in order to assess axial hydraulic specific conductivity (K_s) within tree rings. The results show that branches are more resistant to embolism than stems, and that there are significant differences in embolism resistance among the clones between the two sites. K_s varied between years, sites and clones but the site exerted the most significant effect. Lartimache (more humid site during 2003) trees showed substantially higher K_s than those inhabiting Chassenoix (strongly affected by the 2003 heat and drought wave site). Wood analysis showed a significant year effect for all ring variables and a significant clone effect for all ring variables except for MAD, while the site effect was significant for MRD and MAD. The existence of a genetic control for the study traits indicates that Douglas-fir populations introduced in France may have a selection potential to face extreme climate events like the 2003 heat and drought wave.