Natural triterpenoids from Cecropia lyratiloba are cytotoxic to both sensitive and multidrug resistant leukemia cell lines

The cytotoxicity of four triterpenoids, euscaphic acid (1), tormentic acid (2), 2alpha-acetyl tormentic acid (3), and 3beta-acetyl tormentic acid (4), isolated from the roots of Cecropia lyratiloba (Moraceae) by countercurrent chromatography, was evaluated in vitro in sensitive and multidrug resistant leukemia cell lines. A structure/activity relationship analysis of the compounds was performed. Acetylation of compound 2 at C2 increased its activity by a factor of 2 while acetylation at C3 had a smaller effect. Compound 1 induces death by activation of caspase-3, dependent apoptotic pathway. Furthermore, the four triterpenoids were also active toward a multidrug resistant (MDR) leukemia cell line, overexpressing glycoprotein-P (P-gp). These results reveal the potential of the terpenoids as source for the development of new anti-neoplastic and anti-MDR drugs.     

Seasonal variations in serum concentrations of testosterone,testicular volume and neck circumference of fallow deer (Dama dama) kept ex situ in a tropical region

The fallow deer (Dama dama) is a species of Cervidae commonly kept in captivity, either in commercial farms or in zoos. The reproductive seasonality of this species is well known in the northern hemisphere, where photoperiod is a decisive factor in androgenic activity and, consequently, in the development of secondary sexual characteristics among male adults. The maintenance of this species in tropical regions has been successful, but there are no studies that demonstrate the maintenance of reproductive seasonality under these climatic conditions, which was the objective of the present study. To do so, the present investigation involved 27 fallow deer (D. dama) specimens, of which 14 were adults and 13 prepubescent (<8 months) individuals, all assessed during and outside (December–February) the reproductive season (June–August). The serum concentrations of testosterone, testicular volume, and neck circumference were analyzed among all animals during both seasons. The reproductive season was marked by expressive hormonal concentrations, increasing neck circumference and testicular volume, differing significantly between adults and prepubescent individuals outside the season. Positive correlations were observed among all analyzed variables: mean testicular volume and neck circumference (r = 0.92, p < 0.0001), testicular volume and testosterone concentrations (r = 0.79, p < 0.0001) and between neck circumference and testosterone concentrations (r = 0.67, p < 0.0001). Given the results found, the conclusion is that even under tropical climate conditions the reproductive seasonality of the fallow deer is well defined and may be related to photoperiod.     

MORPHOLOGY AND LIFE HISTORY OF SCYTOSIPHON LOMENTARIA (SCYTOSIPHONACEAE,PHAEOPHYCEAE) FROM THE AZORES1

Morphological and culture studies of Scytosiphon lomentaria (Lyngbye) Link and Microspongium gelatinosum Reinke (Scytosiphonaceae, Phaeophyceae) were undertaken on material collected on the Island of São Miguel, Azores, where both species were commonly found. Erect thalli of S. lomentaria collected in the field were up to 33 cm long and 2.3 mm wide, tubular, hollow, and commonly constricted at intervals. The plurilocular sporangia were positioned in continuous sori on the thallus surface. Ascocysts were present. In the field, M. gelatinosum formed crustose to slightly pulvinate plants, were spongy in texture, and dark brown to black in color, which were circular or irregularly spreading over several centimeters and firmly attached to the substratum. Sessile unilocular sporangia were located in sori on the crust surface. In culture S. lomentaria plurispores developed into Microspongium‐like crustose prostrate thalli that formed unilocular sporangia. Unispores developed into new erect thalli that formed plurilocular sporangia. Sexual reproduction was not observed. In culture, M. gelatinosum unispores developed into erect thalli identical with S. lomentaria. These results are similar to those reported for other areas and suggest the occurrence in the Azorean plants of a monophasic and heteromorphic life history, involving both entities studied.     

Forest edge orientation influences leaf‐cutting ant abundance and plant drought stress in the Brazilian Atlantic forest

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Distribution of the reef manta ray Mobula alfredi and the oceanic manta ray Mobula birostris in the Philippines: a collaborative effort for conservation

Little is known about manta ray population size, structure and connectivity in the Philippines. In collaboration with dive operators, non-governmental organizations and authorities, sightings of manta rays were collated into a single national database. Using in-water photographs and videos gathered through citizen science and dedicated research efforts, this study compiled sightings between 2004 and 2020, showing 22 separate sites throughout the archipelago with manta rays present. A total of 392 individual reef manta rays (Mobula alfredi) and 107 oceanic manta rays (Mobula birostris) were identified from the collected footage. Four specific sites in the provinces of Masbate and Palawan together hosted 89% of all identified individuals and accounted for 95% of sightings, highlighting these areas are key aggregation sites. This study also reports the movements of M. birostris within the Philippines, based on photo-identification of three individuals moving 150 km between Cebu and Masbate. Despite the growing number of recreational divers in Daanbantayan and San Jacinto, an 80% decline in M. birostris sightings was observed at these sites. To ensure effective future conservation, it is recommended that efforts focus on the identification and protection of manta ray hotspots and migratory corridors, the creation of a sustainable tourism framework and, most important, the implementation of mitigation strategies to reduce fisheries interactions.     

Trap-Nesting Hymenoptera and Their Network with Parasites in Recovered Riparian Forests Brazil

Different aspects of human activities can cause environmental change that endanger species persistence, alter species distributions, and lead to changes in antagonistic and mutualistic interactions, whereas deforestation and flooding of riparian forest results in landscapes consisting of patchily distributed riparian forest fragments in a matrix of pastures, plantations, and urban areas. Therefore, we assessed the richness, abundance, and trophic interactions of trap-nesting Hymenoptera and their parasites at four patches of restored riparian forest and at one reference natural fragment, of different sizes and ages, located at the Volta Grande Reservoir, in Minas Gerais and São Paulo states to answer the following questions: (1) Does the richness and abundance of cavity-nesting bees and wasps differ in riparian forest fragments according to the seasonal periods? (2) Does the composition of cavity-nesting bees and wasps vary among restoration and reference sites and between climate seasons (wet and dry)? (3) How do the degrees of specialization of the parasites vary among the patches of forest? We recorded 12 species of wasps, eight of bees, and nine species of parasites. Areas with longer time since restoration (reference site) showed higher species richness. However, the abundance was higher in most recent areas. The composition of bee and wasp assembly has not significantly changed between the climate seasons, although it is different between sampling areas. The richness and abundance were higher in warmer and rainy periods. The rate of bee and wasp mortality was high. The degree of specialization of parasites varies among sampling units, and the network of host-parasite interaction has a modular configuration with generalists and specialists. We concluded that the restored areas with more complex habitat could provide better conditions for the reestablishment of ecological interactions among these insects, the local flora, and other invertebrates, which together contribute to the success of the restored environments.     

Transformation and expression of a gene for herbicide resistance in a Brazilian sugarcane

 Embryogenic calli of the Brazilian sugarcane (Saccharum officinarum L.) genotype SP80–180 were transformed with two plasmids containing genes coding for neomycin phosphotransferase (neo) and phosphinotrycin acetyltransferase (bar), by particle bombardment using an apparatus developed at Copersucar Technology Center. Transformed plants were initially selected on culture medium containing Geneticin, and resistance was confirmed by localized application of a kanamycin solution to leaves of hardened plants at the nursery. A commercial formulation of ammonium gluphosinate was sprayed twice on these antibiotic-resistant plants. The resistant plants were considered co-transformed, and Southern analysis confirmed stable integration of both bar and neo genes. In addition, phosphinotrycin acetyltransferase expression was supported by RT-PCR analysis and neomycin phosphotransferase presence was demonstrated by western blotting. Similar analyses were also performed with micropropagated transformants after three cycles of subculture. Received: 15 December 1999 / Revision received: 15 April 2000 / Accepted: 1 June 2000     

Linking scorpion (Arachnida: Scorpiones) assemblage with fragment restoration in the Brazilian Atlantic Forest

Habitat loss due to forest degradation can induce changes in species richness due to variation in species susceptibility to environmental stress. This is particularly important for species with highly specific microhabitats, such as scorpions that inhabit forest habitats. In this study, the richness and abundance of these arachnids were compared between an old-growth (mature) and secondary (65 years under natural restoration) forests. Seasonal influence was also evaluated by comparing diversity between dry and wet seasons. The animals were collected through nocturnal active search using UV lamps and pitfall traps in both areas (old-growth and secondary). Both environments showed similar breast heights of trees, litter depth, litter dry mass, and understory density, indicating a high level of restoration. Scorpion diversity (characterized by Tityus pusillus, T. neglectus, T. brazilae, Bothriurus asper, and Ananteris mauryi) and abundance were not influenced by the different historical usage of both areas. In contrast, the abundance of these arachnids was highly affected by rain regimes, and increased during the dry season. These results suggest that 65 years was a sufficient time period for restoration, making it possible to maintain similar scorpion assemblages in both environments.