Biochemical and Morphological Changes in Protein Bodies during Germination of Lentil Seeds

Alvarez, J. and Guerra, H. 1985. Biochemical and morphologicalchanges in protein bodies during germination of lentil seeds.—J.exp. BoL 36: 1296–1303. Protein bodies were extracted from lentil (Lens culinaris Medilk,var. castellana) seeds. Proteins from the protein bodies weredegraded during the first 7 d of germination. In some casesthis mobilization of proteins was accompanied by fusion of theprotein bodies into a large central vacuole. The loss of proteinswas paralleled by an increase in the activity of an enzyme systemthat hydrolysed casein. The different kinds of protein bodiesexhibited structural differences; some displayed uniform material,others coagulated or semi-coagulated material and the thirdkind displayed inclusions. Key words: Lentil, protein bodies, seed germination     

Phlebotominae of epidemiological importance in cutaneous leishmaniasis in northwestern Argentina: risk maps and ecological niche models

In Argentina, 58.2% out of the 8126 Cutaneous Leishmaniasis (CL) incident cases accumulated from 1954 to 2006 were reported in the provinces of Salta and Jujuy. The aim of this study was to develop an exploratory risk map and a potential distribution map of the vector, in order to offer recommendations for CL prevention. A total of 12 079 Phlebotominae (Diptera: Psychodidae) belonging to the species Lutzomyia neivai (Pinto), Lu. migonei (França), Lu. cortelezzii (Brèthes), Lu. shannoni (Dyar), Lu. quinquefer (Dyar) and Brumptomyia spp. (França & Parrot) were captured. Potential distribution models were created for two species, Lu. neivai (incriminated vector of Leishmania braziliensis) and Lu. migonei, associated with domestic animals in Argentina and that in turn could be involved as a link between zoonotic transmission cycles and anthropozoonotic. The Maximum Entropy Modeling System (MaxEnt) was used. The Jackknife test was performed, and the ‘rainfall of the driest month’ was the variable that best generalized the models. Accuracy was evaluated by the area under the curve (AUC) and validated by the Cohen's kappa index. This approximation provides a new analytical resource of high potential for the prevention of the disease, in order to allocate resources properly and to develop the most suitable strategies for action.     

Energy storage during the transition from endogenous to exogenous feeding in Australian redclaw crayfish Cherax quadricarinatus (Von Martens, 1898)

Summary

The Australian redclaw crayfish Cherax quadricarinatus hatches at an advanced stage. Two post-hatching stages rely on yolk reserves before the organism becomes a juvenile. After a juvenile appears, the yolk is depleted and young crayfish might spend a few days among female pleopods before starting to feed independently. During this phase, the juvenile organism needs alternative energy sources. Offspring from three females were analyzed with histological and histochemical techniques, from hatching until reaching the 2-week juvenile stage, to trace digestive system development and internal organ lipid and glycogen accumulation. Neutral lipids are stored in specialized cells of the hepatopancreatic tissue until the juvenile stage is reached. An increasing rate of accumulation was found. Glycogen was stored in hepatopancreas and tail muscle cells until post-embryo II, and no increasing or decreasing rate was found in storage functions.     

Isolation and characterization of six microsatellites in the Mexican beaded lizard Heloderma horridum

Six polymorphic microsatellite loci were isolated and characterized in the threatened Mexican beaded lizard, Heloderma horridum. The number of alleles per locus ranged from three to 12, with observed heterozygosity estimates ranging from 0.00 to 0.77, and expected heterozygosity estimates ranging from 0.00 to 0.73. These microsatellites will provide a valuable tool for the investigation of the genetic variation and structure of both wild and captive H. horridum populations.     

Burkholderia species are ancient symbionts of legumes

Burkholderia has only recently been recognized as a potential nitrogen-fixing symbiont of legumes, but we find that the origins of symbiosis in Burkholderia are much deeper than previously suspected. We sampled 143 symbionts from 47 native species of Mimosa across 1800 km in central Brazil and found that 98% were Burkholderia . Gene sequences defined seven distinct and divergent species complexes within the genus Burkholderia . The symbiosis-related genes formed deep Burkholderia -specific clades, each specific to a species complex, implying that these genes diverged over a long period within Burkholderia without substantial horizontal gene transfer between species complexes.     

Net greenhouse gas fluxes in Brazilian ethanol production systems

Biofuels are both a promising solution to global warming mitigation and a potential contributor to the problem. Several life cycle assessments of bioethanol have been conducted to address these questions. We performed a synthesis of the available data on Brazilian ethanol production focusing on greenhouse gas (GHG) emissions and carbon (C) sinks in the agricultural and industrial phases. Emissions of carbon dioxide (CO₂) from fossil fuels, methane (CH₄) and nitrous oxide (N₂O) from sources commonly included in C footprints, such as fossil fuel usage, biomass burning, nitrogen fertilizer application, liming and litter decomposition were accounted for. In addition, black carbon (BC) emissions from burning biomass and soil C sequestration were included in the balance. Most of the annual emissions per hectare are in the agricultural phase, both in the burned system (2209 out of a total of 2398 kg C_eq), and in the unburned system (559 out of 748 kg C_eq). Although nitrogen fertilizer emissions are large, 111 kg C_eq ha^?1 yr^?1, the largest single source of emissions is biomass burning in the manual harvest system, with a large amount of both GHG (196 kg C_eq ha^?1 yr^?1). and BC (1536 kg C_eq ha^?1 yr^?1). Besides avoiding emissions from biomass burning, harvesting sugarcane mechanically without burning tends to increase soil C stocks, providing a C sink of 1500 kg C ha^?1 yr^?1 in the 30 cm layer. The data show a C output: input ratio of 1.4 for ethanol produced under the conventionally burned and manual harvest compared with 6.5 for the mechanized harvest without burning, signifying the importance of conservation agricultural systems in bioethanol feedstock production.     

Performance and fate of tree seedlings on and around nests of the leaf‐cutting ant Atta cephalotes: Ecological filters in a fragmented forest

Habitat fragmentation is currently the most pervasive anthropogenic disturbance in tropical forests and some species of leaf‐cutting ants of the genus Atta (dominant herbivores in the neotropics) have become hyper‐abundant in forest edges where their nests directly impact up to 6% of the forest area. Yet, their impacts on the regeneration dynamics of fragmented forests remain poorly investigated. Here we examine the potential of Atta cephalotes nests to function as ecological filters impacting tree recruitment. Growth, survival and biomass partitioning of experimentally planted seedlings (six tree species) were examined at eight spatially independent A. cephalotes colonies in a large Atlantic Forest fragment. Seedling performance and fate (leaf numbers and damage) were monitored up to 27 months across three habitats (nest centre, nest edge and forest understorey). Plants at illuminated nest centres showed twice the gross leaf gain as understorey individuals. Simultaneously, seedlings of all species lost many more leaves at nests than in the forest understorey, causing a negative net leaf gain. Net leaf gain in the shaded understorey ranged from zero (Licania and Thyrsodium species) to substantial growth for Copaifera and Virola, and intermediate levels little above zero for Protium and Pouteria. Also seedling survival differed across habitats and species, being typically low in the centre and at the edge of nests where seedlings were often completely defoliated by the ants. Lastly, seedling survival increased strongly with seed size at nest edges while there was no such correlation in the forest. Our results suggest that Atta nests operate as ecological filters by creating a specific disturbance regime that differs from other disturbances in tropical forests. Apparently, Atta nests favour large‐seeded tree species with resprouting abilities and the potential to profit from a moderate, nest‐mediated increase in light availability.     

Do abandoned nests of leaf‐cutting ants enhance plant recruitment in the Atlantic Forest?

The role played by abandoned nests of leaf‐cutting ants (Atta spp.) as a small‐scale disturbance regime that affects plant recruitment, species coexistence and forest regeneration remains poorly investigated. Here we examine whether abandoned nests of Atta cephalotes serve as regeneration niches and operate as particular plant recruitment habitats, favouring forest regeneration after ant activities cease and leading to the establishment of taxonomically/ecologically distinct plant assemblages. Soil properties, canopy openness, light availability and regenerating plant assemblages were evaluated across 18 nests and adjacent control plots in a large remnant of Atlantic Forest in north‐east Brazil from December 2004 to December 2005. Surprisingly, nests and control plots exhibited very similar light environments irrespective of nest age, but nest soils exhibited substantial reductions in carbon content (1.45 ± 0.24 vs. 1.79 ± 0.13%) and organic matter (2.50 ± 0.41 vs. 3.08 ± 0.23%), and proved to be much more resistant to penetration (30.57 ± 6.08 vs. 39.48 ± 7.53 mm). Functional signature of regenerating plant assemblages exhibited little variation across both habitat types, as they were dominated by pioneer, small‐seeded and vertebrate‐dispersed species. However, abandoned nests exhibited less dense, impoverished and more homogeneous regenerating plant assemblages at local and landscape scale; they clearly lacked nest‐dependent plant species and represented floristic subsets of the flora inhabiting the undisturbed forest. This recruitment bottleneck was transient in the long term because nest‐related effects ameliorated in older nests. Our results suggest that, unlike treefall gaps, abandoned nests represent temporary (relatively long‐lasting) islands of unsuitable substrate that reduce plant recruitment, retard forest regeneration, and fail in providing a special regeneration niche able to promote species coexistence and plant diversity.     

Physical illness in patients with severe mental disorders. II. Barriers to care, monitoring and treatment guidelines, plus recommendations at the system and individual level

Physical disorders are, compared to the general population, more prevalent in people with severe mental illness (SMI). Although this excess morbidity and mortality is largely due to modifiable lifestyle risk factors, the screening and assessment of physical health aspects remains poor, even in developed countries. Moreover, specific patient, provider, treatment and system factors act as barriers to the recognition and to the management of physical diseases in people with SMI. Psychiatrists can play a pivotal role in the improvement of the physical health of these patients by expanding their task from clinical psychiatric care to the monitoring and treatment of crucial physical parameters. At a system level, actions are not easy to realize, especially for developing countries. However, at an individual level, even simple and very basic monitoring and treatment actions, undertaken by the treating clinician, can already improve the problem of suboptimal medical care in this population. Adhering to monitoring and treatment guidelines will result in a substantial enhancement of physical health outcomes. Furthermore, psychiatrists can help educate and motivate people with SMI to address their suboptimal lifestyle, including smoking, unhealthy diet and lack of exercise. The adoption of the recommendations presented in this paper across health care systems throughout the world will contribute to a significant improvement in the medical and related psychiatric health outcomes of patients with SMI.