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The article presents author's comments on the synthetic horsepox viruses with thedebate on dual use research. It focuses on the dual use research of concern (DURC), as the method that can be used to assemble horsepox virus can be used to develop variola which is the virus that causes smallpox. It focuses on recovering vaccinia virus (VACV) from a bacmid.

Context:The resin from the trunk wood ofVirola oleifera(Schott) A. C. Smith (Myristicaceae) is used in folk medicine to hasten wound repair and to treat pain and inflammatory conditions, and our previous report indicated the anti-oxidative properties in other oxidative stress model. Objective:To investigate the protective effects of resin fromV. oleiferain two experimental models of gastric ulcer oxidative-stress dependent. Materials and methods:Plant material was collected and the resin was subjected to partitioning with organic solvents. The buthanol fraction was subjected to chromatographic and spectrometric methods for isolation and structural elucidation. The resin was quantified for polyphenols and flavonoids by colorimetric methods. Furthermore, the antioxidant activity of resin was determined by three different methods. The ulcers were induced acutely in Swiss male mice with ethanol/HCl and indomethacin using single-doses of 10 and 100 mg/kg. The gastroprotection of the experimental groups was comparable to reference control lansoprazole (3 mg/kg). Results:The high content of polyphenols (∼82%) and the presence of epicatechin and eriodictyol were determined. The LD50was estimated at 2500 mg/kg. At minimum (10 mg/kg) and maximum (100 mg/kg) dosage of resin, both in ethanol/HCl as indomethacin ulcer induction models demonstrate reduction of lesions (minimum: ∼97% and ∼66%; maximum: ∼95% and ∼59%). Discussion:The gastroprotection might be related to tannins, phenolic acids and flavonoids present in the resin by antioxidant properties. Conclusions:The results indicate that this resin has gastroprotective activity probably associated with the presence of phenolic antioxidant substances. [ABSTRACT FROM AUTHOR]

The development of new routes and strategies for nanotechnology applications that only employ green synthesis has inspired investigators to devise natural systems. Among these systems, the synthesis of gold nanoparticles using plant extracts has been actively developed as an alternative, efficient, cost-effective, and environmentally safe method for producing nanoparticles, and this approach is also suitable for large-scale synthesis. This study reports reproducible and completely natural gold nanocrystals that were synthesized using Virola oleifera extract. V. oleifera resin is rich in epicatechin, ferulic acid, gallic acid, and flavonoids (i.e., quercetin and eriodictyol). These gold nanoparticles play three roles. First, these nanoparticles exhibit remarkable stability based on their zeta potential. Second, these nanoparticles are functionalized with flavonoids, and third, an efficient, economical, and environmentally friendly mechanism can be employed to produce green nanoparticles with organic compounds on the surface. Our model is capable of reducing the resin of V. oleifera, which creates stability and opens a new avenue for biological applications. This method does not require painstaking conditions or hazardous agents and is a rapid, efficient, and green approach for the fabrication of monodisperse gold nanoparticles. [ABSTRACT FROM AUTHOR]

Contrast-induced nephropathy (CIN) is an iatrogenic medical event for which there is not yet a successful therapy. Increasing evidence in rodents has suggested that this disease is associated with renal tubular and vascular injury that is triggered directly by oxidative stress. In the present study, we evaluated whether the antioxidant resin from Virola oleifera (RV) could attenuate renal damage in an experimental mouse model of CIN. Adult male Swiss mice were divided into six groups and pre-treated orally with RV (10, 100 and 300 mg/kg), N-acetylcysteine (200 mg/kg) or vehicle for 5 days before the induction of CIN and Control group. Renal function was assessed by measuring plasma creatinine and urea levels. Additionally, renal oxidative stress and apoptosis/cell viability were determined with flow cytometry. Finally, kidney tissues were sectioned for histopathological examination. In this CIN model, pre-treatment with RV improved renal function, lowered the mortality rate, and reduced oxidative stress and apoptosis in both the medulla and cortex renal cells in a dose-dependent manner. Moreover, the RV treatment had beneficial effects on kidney histopathology that were superior to the standard treatment with N-acetylcysteine. These data suggest that because of its antioxidative and antiapoptotic effects and its ability to preserve renal function, resin from Virola oleifera may have potential as a new therapeutic approach for preventing CIN. [ABSTRACT FROM AUTHOR]

Key message: Genetic diversity appears to be unaffected by disturbance in a stand of the light-demanding Neotropical tree V. michelii. Although spatial genetic structure is modified in post-disturbance cohorts, mixing of seeds from different mother trees in canopy gaps appears to efficiently maintain genetic admixture. Context: The interplay between genetic and demographic processes has major consequences on population viability. Population size affects demographic trends, while genetic diversity insures viability by reducing risks of inbreeding depression and by maintaining adaptive potential. Yet, the consequences of increases in census size (as opposed to effective size) on genetic diversity of forest populations are poorly known. Aims: We have studied the structure of genetic diversity in populations of saplings of the light-responsive tree, Virola michelii (Myristicaceae, the nutmeg family), in two plots having undergone different levels of canopy-gap opening disturbance. This allowed us to test the 'intermediate disturbance' hypothesis, which generally applies to species diversity, at the intra-specific scale. Methods: Levels and distribution of genetic diversity were compared between plots and between life stages. Sapling parentage was analysed to infer each adult tree's contribution to regeneration. Results: Genetic diversity was higher, and spatial genetic structure was stronger in the post-disturbance than in the control seedling population. Parentage analysis suggested that a limited number of parents contributed to most of the regeneration, but that efficient mixing of their progeny may have enhanced the diversity of saplings occupying canopy gaps. Conclusion: A mixture of demo-genetic processes may contribute to maintain genetic diversity in spite of, or possibly due to, ecosystem disturbance in V. michelii. [ABSTRACT FROM AUTHOR]

The abundance of dalli- and truei-types of Dall's porpoise Phocoenoides dalli was assessed based on the multicovariate distance sampling method, using line-transect survey data collected in the western central part of the Sea of Okhotsk between 1990 and 2010. The estimated abundance are 77,856 individuals in 1990, 72,303 in 2009 and 111,402 in 2010 for dalli-type, and 120,198 individuals in 1990 and 101,173 in 2009 for truei-type. Abundance was not estimated for truei-type in 2010 because of small sample size. During this period, abundance seemed to fluctuate, but statistically significant trends could not be detected in abundance. Considerable small numbers of sightings of truei-type in 2010 could be attributed to insufficient survey effort in the southeastern region and warmer temperature in the southwestern region. We surmise that the abundance of Dall's porpoise migrating into the Sea of Okhotsk during summer depends on interannual shifts in environmental conditions and resulting prey availability. [ABSTRACT FROM AUTHOR]

The Myristicaceae is a member of the early diverging angiosperm order Magnoliales; however, the family is poorly represented by fossil collections. We describe Virola dominicana sp. nov. (Myristicaceae), the first record of fossilized Myristicaceae flowers, from mid-Tertiary (45-15 million years ago) Dominican amber. The description is based on 24 male flowers in 17 pieces of amber, thus providing some indication of intraspecific variation, including a two-tepaled flower. Diagnostic characters of the new species are the long-simple or few-branched trichomes on the perianth margins, the small pollen grains, and a short staminal column. These fossils also show co-occurring insects, some of which could be Virola pollinators. It is speculated that V. dominicana disappeared from Hispaniola during the Pliocene-Pleistocene cooling events leaving no native members of the Myristicaceae in this region today. Additionally, these fossils demonstrate that Myristicaceae was present in the Western Hemisphere during the mid-Tertiary. [ABSTRACT FROM AUTHOR]

The phytochemical study of Virola sebifera leaves led to the isolation of three lignans: (+)-sesamin, (-)-hinokinin, and (-)- kusunokinin and three flavonoids: quercetin-3-O-α-L-rhamnoside, quercetin-3-O-β-D-glucoside, and quercetin-3-methoxy-7-O- β-D-glucoside by using techniques as high-speed counter-current chromatography and high-performance liquid chromatography. The crude extracts, fractions, and isolated compounds were evaluated for their insecticidal and fungicidal potential against Atta sexdens rubropilosa and its symbiotic fungus Leucoagaricus gongylophorus. The bioassay results showed a high insecticidal activity for the methanol crude extract of the leaves of V. sebifera and its n-hexane, dichloromethane and ethyl acetate fractions. The fungicidal bioassay revealed high toxicity of the lignans against L. gongylophorus. [ABSTRACT FROM AUTHOR]

Abstract: Seed dispersal is critical to understanding forest dynamics but is hard to study because tracking seeds is difficult. Even for the best-studied dispersal system of the Neotropics, Virola nobilis, the dispersal kernel remains unknown. We combined high-resolution GPS/3D-acceleration bird tracking, seed-retention experiments, and field observations to quantify dispersal of V. nobilis by their principal dispersers, Ramphastos toucans. We inferred feeding events from movement data, and then estimated spatio-temporally explicit seed-dispersal kernels. Wild toucans moved an average of 1.8 km d−1 with two distinct activity peaks. Seed retention time in captive toucans averaged 25.5 min (range 4–98 min). Estimated seed dispersal distance averaged 144 ± 147 m, with a 56% likelihood of dispersal >100 m, two times further than the behaviour-naive estimate from the same data. Dispersal was furthest for seeds ingested in the morning, and increased with seed retention time, but only up to 60 min after feeding. Our study supports the long-standing hypothesis that toucans are excellent dispersers of Virola seeds. To maximize seed dispersal distances trees should ripen fruit in the morning when birds move the most, and produce fruits with gut-processing times around 60 min. Our study demonstrates how new tracking technology can yield nuanced seed dispersal kernels for animals that cannot be directly observed. [Copyright &y& Elsevier]

Prolific fine root growth coupled with small accumulations of dead fine roots indicate rapid rates of fine root production, mortality and decay in young tree plantations in lowland Costa Rica. However, published studies indicate that fine roots decay relatively slowly in tropical forests. To resolve this discrepancy, we used the intact-core technique to quantify first-year decay rates of fine roots in four single-species plantations of native tree species. We tested three hypotheses: first, that fine roots from different tree species would decay at different rates; second, that species having rapid fine root growth rates would also have rapid rates of fine root decay; and third, that differences in fine root decay among species could be explained by fine root chemistry variables previously identified as influencing decay rates. Fine roots in Virola koschnyi plantations decayed very slowly ( k = 0.29 ± 0.15 year−1); those of Vochysia guatemalensis decayed seven times faster ( k = 2.00 ± 0.13 year−1). Decay rates of the remaining two species, Hieronyma alchorneoides and Pentaclethra macroloba, were 1.36 and 1.28 year−1, respectively. We found a positive, marginally significant correlation between fine root decay rates and the relative growth rates of live fine roots ( R = 0.93, n = 4, P = 0.072). There was a highly significant negative correlation between fine root decay and fine root lignin:N ( R = 0.99, P = 0.01), which supports the use of lignin:N as a decay-controlling factor within terrestrial ecosystem models. The decay rates that we observed in this single study location encompassed the entire range of fine root decay rates previously observed in moist tropical forests, and thus suggest great potential for individual tree species to alter belowground organic matter and nutrient dynamics within a biotically rich rainforest environment. [ABSTRACT FROM AUTHOR]

The Costa Rican government has provided incentives for reforestation programs since 1986 and initiated a Payment for Environmental Services program in 1996. These incentives yielded native species reforestation programs throughout the country. This research aims to provide information about growth, carbon sequestration, and management of seven native tree species (Vochysia guatemalensis, Vochysia ferruginea, Hyeronima alchorneoides, Calophyllum brasiliense, Terminalia amazonia, Virola koschnyi, and Dipteryx panamensis) growing in small and medium-sized plantations in the Caribbean and Northern lowlands of Costa Rica. A total of 179 plots were evaluated in 32 farms. Overall, I found that V. guatemalensis, V. ferruginea, H. alchorneoides, and T. amazonia were the species with the fastest diameter, total height, and volume growth; and T. amazonia and D. panamensis sequestered more carbon. Moreover, I found that the plantations that had been thinned before this assessment had the best growth. The results of the present research enhance the criteria elaborated in previous research findings to improve species choices for reforestation and silvicultural management in Costa Rica and in other regions with similar ecological features. Furthermore, they support the concept that tropical plantations can serve diverse economic, social, and ecological functions that may ultimately help reduce atmospheric CO2 accumulation. [ABSTRACT FROM AUTHOR]

Aryltetralone lignans bearing methylenedioxy groups ( 1a–b; 2a–b ) were isolated from seeds of Virola sebifera . Their antioxidant activities were evaluated by inhibition of lipid peroxidation as indicated by TBARS and chemiluminescence emission (CL) assays. The lignan 1c , 'having a 2′-hydroxy-4′,5′-methylenedioxyphenyl group, was the most active compound with TBARS/CL Q 1/2 values of 0.89 and 0.10  µg/mL, respectively. The catechol derivatives 3 and 4 , obtained by demethylenation of lignans 1a and 2a , were of similar activity to 1c , and all were much more effective as antioxidants than α-tocopherol. [ABSTRACT FROM AUTHOR]

Contrary to the generally accepted life history theory regarding sequential hermaphroditism (‘size-advantage model’), we have recently identified ‘mini males’ inLythrypnus dalli, the bluebanded goby. These are small (female-sized) fish that appear male based on their external genitalia. We investigated the reproductive anatomy and demography of these mini males. Based on their small size and the sexual plasticity of this species, we expected that mini males are not actually reproductively functioning males. However, when we examined their gonad anatomy, with particular attention to the male-typical accessory gonadal structure (AGS), we found that mini males have gonads that are comparable to those of nesting males in relative size and the percentage of tissue that is ‘male’ (testicular and AGS). Although this is contradictory to theories of sperm competition in alternative male phenotypes, reproductive strategies of these two types of males were clearly distinguishable based on their AGS content - as described in other examinations of differing ejaculate quality in alternative male phenotypes in the Gobiidae. Regular sampling of theL. dallipopulation showed that mini males make up a small fraction of the small size classes and that as the breeding season progressed, mini male frequency decreased and standard length increased significantly - thus allowing us to discuss their role within the social system. Based on these findings as well as comparisons with other species with multiple male phenotypes, we can begin to categorizeL. dallimales as either bourgeois or parasitic, primarily based on their secondary sex characteristics and AGS contents. [ABSTRACT FROM AUTHOR]

Variation in traits affecting seed dispersal in plants has been attributed to selection exerted by dispersal agents. The potential for such selection was investigated in Virola calophylla (Myristicaceae) in Manú National Park, Peru, through identification of seed dispersal agents and of tree and fruit traits significantly affecting the quantity of seeds dispersed. Seventeen bird and one primate species (the spider monkey, Ateles paniscus) dispersed its seeds. Spider monkeys dispersed the majority of seeds (a minimum of 83% of all dispersed seeds). Visitation by dispersal agents depended only on the quantity of ripe fruit available during a tree observation. In contrast, seed removal increased with both greater quantity of ripe fruit and aril: seed ratio. When analyzed separately, seed removal by birds increased only with greater aril: seed ratio, whereas seed removal by spider monkeys was affected by the quantity of ripe fruit and phenological stage. The finding that dispersal agents responded differently to some tree and fruit traits indicates not only that dispersal agents can exert selection on traits affecting seed dispersal, but also that the resulting selection pressures are likely to be inconsistent. This conclusion is supported by the result that the proportion of the seed crop that was dispersed from individual trees, which accounted for cumulative dispersal by all agents, was not influenced by any tree or fruit trait evaluated. Comparing these results with those from studies of V. sebifera and V. nobilis in Panama revealed that the disperser assemblages of these three Virola species were congruent in their similar taxonomic representation. In Panama the proportion of V. nobilis seed crop dispersed was related positively to aril: seed ratio and negatively to seed mass, a result not found for V. calophylla in Peru. The greater importance of dispersal by primates versus birds in V. calophylla, relative to V. nobilis, may explain this difference. Thus, variation in disperser assemblages at regional scales can be another factor contributing to inconsistency in disperser-mediated selection on plant traits. [ABSTRACT FROM AUTHOR]

Eight highly polymorphic microsatellite loci were developed for Virola flexuosa from a (CA) n-enriched genomic library for population and seed dispersal studies in eastern Ecuador. Loci show a high level of variation with the number of alleles ranging from 13 to 27. Observed and expected heterozygosities were from 0.313 to 0.896 and 0.552 to 0.937, respectively. The high levels of polymorphism and exclusionary power of the developed markers will likely prove very useful in direct measurement of seed dispersal. [ABSTRACT FROM AUTHOR]