A review of the palm genus <Emphasis Type="Italic">Acrocomia</Emphasis>: Neotropical green gold

The genus Acrocomia, popularly known as macaw palm or macaúba, occurs in savanna areas and open forests of tropical America, with distribution from Central to southern South America. They are important oleaginous palm trees, due to their role in ecosystems and local economies and their potential for biofuel production and vegetable oil. Although the taxonomy of the genus is not resolved because of observed phenotypic diversity in A. aculeata (Jacq.) Lodd. ex Mart., there are several conflicting treatments. Some authors recognize three caulescent spp. occurring in South America: A. aculeata, A. intumescens Drude, and A. totai Mart, although a new one was described recently—Acrocomia corumbaensis. Because some Latin American governments want to expand production of macaw palm in their territory as raw material for agro-energy, several groups have been encouraged to study this genus, focusing on the production of biodiesel, seed germination, phenotypic aspects, and genetic diversity. The goal of this review is to compile key information available in the literature and herbarium data, focusing on South American populations of the genus.     

Ant-partners play a minor role on occurrence of the myrmecophilous butterfly <Emphasis Type="Italic">Leptotes cassius</Emphasis> in its host plant

Ant-related oviposition in facultatively myrmecophilous lycaenid butterflies is common, but not universal. In fact, our knowledge of ant-related oviposition in lycaenids is based on some common species (e.g., Rekoa marius, Allosmaitia strophius, Parrhasius polibetes), which limits generalizations about these systems. In this study, we experimentally investigated whether the oviposition pattern of the florivorous lycaenid Leptotes cassius was influenced by the presence of Camponotus ants and whether larvae were attended, rather than attacked, by ants. This might be evidence of myrmecophily. Both L. cassius and Camponotus ants occur on Bionia coriacea, an extrafloral nectaried legume shrub that grows in the Brazilian cerrado. Plants were randomly assigned to ant-present and ant-excluded treatments and were observed twice throughout the short reproductive season. Larvae of L. cassius were tended by ants, whose attendance was characterized by active antennation on the last body segments of the caterpillars. Therefore, Camponotus can be considered a partner of L. cassius. Lycaenid abundance was on average 1.9- and 1.21-fold higher in plants with ants in each sampling period, respectively, indicating a tendency of L. cassius to occur in plants with ants. Nonetheless, results were not statistically significant, suggesting that in this case ants are not a major cue for lycaenid oviposition. In many ant–lycaenid mutualisms, butterfly immatures benefit from reduced parasitism rates. However, no L. cassius immature, regardless of ant presence or absence, was parasitized. Furthermore, larvae may occur inside flower buds that may provide protection from natural enemies; thus, ants may not be required for immature protection.     

Effects of Self‐Conditioning Techniques (Self‐Hypnosis) in Promoting Weight Loss in Patients with Severe Obesity: A Randomized Controlled Trial

Objective

The usefulness of the rapid‐induction techniques of hypnosis as an adjunctive weight‐loss treatment has not been defined. This randomized controlled trial evaluated whether self‐conditioning techniques (self‐hypnosis) added to lifestyle interventions contributed to weight loss (primary outcome), changes in metabolic and inflammatory variables, and quality of life (QoL) improvement (secondary outcomes) in severe obesity.

Methods

Individuals (with BMI = 35‐50 kg/m²) without organic or psychiatric comorbidity were randomly assigned to the intervention (n = 60) or control arm (n = 60). All received exercise and behavioral recommendations and individualized diets. The intervention consisted of three hypnosis sessions, during which self‐hypnosis was taught to increase self‐control before eating. Diet, exercise, satiety, QoL, anthropometric measurements, and blood variables were collected and measured at enrollment and at 1 year (trial end).

Results

A similar weight loss was observed in the intervention (?6.5 kg) and control (?5.6 kg) arms (β = ?0.45; 95% CI: ?3.78 to 2.88; P = 0.79). However, habitual hypnosis users lost more weight (?9.6 kg; β = ?10.2; 95% CI: ?14.2 to ?6.18; P < 0.001) and greatly reduced their caloric intake (?682.5 kcal; β = ?643.6; 95% CI: ?1064.0 to ?223.2; P = 0.005) in linear regression models. At trial end, the intervention arm showed lower C‐reactive protein values (β = ?2.55; 95% CI: ?3.80 to ?1.31; P < 0.001), higher satiety (β = 19.2; 95% CI: 7.71‐30.6; P = 0.001), and better QoL (β = 0.09; 95% CI: 0.02‐0.16; P = 0.01).

Conclusions

Self‐hypnosis was not associated with differences in weight change but was associated with improved satiety, QoL, and inflammation. Indeed, habitual hypnosis users showed a greater weight loss.

     

Cooperative foraging in neotropical pseudoscorpions: effects of prey changes on behavioral adjustments of colonies

The pseudoscorpion Paratemnoides nidificator is a generalist predator that captures large arthropods that live on tree trunks. Few pseudoscorpions species show some degree of sociality. We investigated how colonies of the pseudoscorpion P. nidificator adjust their cooperative capture behavior under a situation of changing prey types as a simulation of variation in prey availability. We hypothesized that colonies would be more efficient at prey capture under repeated exposure to the same prey, and that the change in the availability of prey would be followed by new behavioral adjustments to adequately exploit the new prey. Eight experimental colonies housed in the laboratory received repetitions of three different ant species as prey. The number of pseudoscorpions attacking the prey, the number of behavioral acts, and the time expended subduing prey were evaluated as measures of prey capture performance, in relation to repetitive exposure to the same prey and also in relation to prey type changes. However, only individuals’ recruitment significantly responded to prey type exposure. Prey capture behavior was heterogeneous among colonies, resulting in highly variable behavioral responses. Colonies showed a tendency toward increasing capture success through repeated prey type exposure. However, 50% of the colonies were unable to capture the new prey type and died of starvation. Although it is a generalist predator, prey capture behavior could depend on different coordination components for subduing and handling large prey. Therefore, changes in prey availability could cause the attenuation of a cooperative relationship in some colonies, making them more prone to failure during capture.     

Separation used for purification of recombinant proteins

The purification of molecules from recombinant cells may be strongly influenced by the molecular biology of gene isolation and expression. At the beginning of the process there may be a demand for information on the minute amounts of proteins and thus for ever increasingly sensitive techniques. Purification of recombinant proteins can differ from conventional purifications in several ways, depending on the solubility of the protein, occurrence in inclusion bodies, creation of fusion proteins with tags that enable simpler purification. Sometimes a (re)naturation step is required to get a bioactive protein. On the other hand, the techniques used in separation are essentially the same as for purification from the natural source and environment.     

A conceptual model of organo-mineral interactions in soils: self-assembly of organic molecular fragments into zonal structures on mineral surfaces

In this paper, we propose a structure for organo-mineral associations in soils based on recent insights concerning the molecular structure of soil organic matter (SOM), and on extensive published evidence from empirical studies of organo-mineral interfaces. Our conceptual model assumes that SOM consists of a heterogeneous mixture of compounds that display a range of amphiphilic or surfactant-like properties, and are capable of self-organization in aqueous solution. An extension of this self-organizational behavior in solution, we suggest that SOM sorbs to mineral surfaces in a discrete zonal sequence. In the contact zone, the formation of particularly strong organo-mineral associations appears to be favored by situations where either (i) polar organic functional groups of amphiphiles interact via ligand exchange with singly coordinated mineral hydroxyls, forming stable inner-sphere complexes, or (ii) proteinaceous materials unfold upon adsorption, thus increasing adhesive strength by adding hydrophobic interactions to electrostatic binding. Entropic considerations dictate that exposed hydrophobic portions of amphiphilic molecules adsorbed directly to mineral surfaces be shielded from the polar aqueous phase through association with hydrophobic moieties of other amphiphilic molecules. This process can create a membrane-like bilayer containing a hydrophobic zone, whose components may exchange more easily with the surrounding soil solution than those in the contact zone, but which are still retained with considerable force. Sorbed to the hydrophilic exterior of hemimicellar coatings, or to adsorbed proteins, are organic molecules forming an outer region, or kinetic zone, that is loosely retained by cation bridging, hydrogen bonding, and other interactions. Organic material in the kinetic zone may experience high exchange rates with the surrounding soil solution, leading to short residence times for individual molecular fragments. The thickness of this outer region would depend more on input than on the availability of binding sites, and would largely be controlled by exchange kinetics. Movement of organics into and out of this outer region can thus be viewed as similar to a phase-partitioning process. The zonal concept of organo-mineral interactions presented here offers a new basis for understanding and predicting the retention of organic compounds, including contaminants, in soils and sediments.     

Transfection of Escherichia coli Spheroplasts II. Relative Infectivity of Native, Denatured, and Renatured Lambda, T7, T5, T4, and P22 Bacteriophage DNAs

The change of infectivity of phage DNAs after heat and alkali denaturation (and renaturation) was measured. T7 phage DNA infectivity increased 4- to 20-fold after denaturation and decreased to the native level after renaturation. Both the heavy and the light single strand of T7 phage DNA were about five times as infective as native T7 DNA. T4 and P22 phage DNA infectivity increased 4- to 20-fold after denaturation and increased another 10- to 20-fold after renaturation. These data, combined with other authors' results on the relative infectivity of various forms of phiX174 and lambda DNAs give the following consistent pattern of relative infectivity. Covalently closed circular double-stranded DNA, nicked circular double-stranded DNA, and double-stranded DNA with cohesive ends are all equally infective and also most highly infectious for Escherichia coli lysozyme-EDTA spheroplasts; linear or circular single-stranded DNAs are about 1/5 to 1/20 as infective; double-stranded DNAs are only 1/100 as infective. Two exceptions to this pattern were noted: lambda phage DNA lost more than 99% of its infectivity after alkaline denaturation; this infectivity could be fully recovered after renaturation. This behavior can be explained by the special role of the cohesive ends of the phage DNA. T5 phage DNA sometimes showed a transient increase in infectivity at temperatures below the completion of the hyperchròmic shift; at higher temperatures, the infectivity was completely destroyed. T5 DNA denatured in alkali lost more than 99.9% of its infectivity; upon renaturation, infectivity was sometimes recovered. This behavior is interpreted in terms of the model of T5 phage DNA structure proposed by Bujard (1969). The results of the denaturation and renaturation experiments show higher efficiencies of transfection for the following phage DNAs (free of single-strand breaks): T4 renatured DNA at 10(-3) instead of 10(-5) for native DNA; renatured P22 DNA at 3 x 10(-7) instead of 3 x 10(-9) for native DNA; and denatured T7 DNA at 3 x 10(-6) instead of 3 x 10(-7) for native DNA.     

Comparison of some live organisms and artificial diet as feed for Asian catfish Clarias macrocephalus (Günther) larvae

Experiments were conducted to evaluate the efficacy of five live organisms (Artemia, Brachionus calyciflorus, Chironomus plumosus, Moina macrocopa and Tubifex sp.) and an artificial diet (40% protein) in the larval rearing of Asian catfish Clarias macrocephalus. The larvae were fed three times daily starting at the onset of exogenous feeding. Results showed that the catfish larvae utilized the live organisms more efficiently than the artificial diet. The Tubifex‐fed larvae consistently showed the highest growth rate. In trial 1, length increment (64.9 mm), weight gain (3192 mg) and specific growth rate (13.1%) after 8 weeks of feeding were significantly higher (P < 0.05) in catfish larvae given Tubifex than those in all other treatments. In trial 2, length increment after 4 weeks of feeding was highest in larvae fed Tubifex (22.9 mm) although it did not significantly differ from that of larvae given Moina (21.0 mm). However, weight gain of larvae fed Tubifex (253.0 mg) was significantly higher than that of larvae fed Moina (171.6 mg). The specific growth rate was highest for larvae fed Tubifex (15.0%) followed by larvae fed Artemia (14.5%), Moina (14.4%) and Chironomus (12.0%). Survival rates of the catfish larvae ranged from 9 to 39% after 8 weeks in trial 1 and from 26 to 83% after 4 weeks in trial 2. The present results suggest that Tubifex is an excellent food and a potential substitute for Artemia in the rearing of catfish larvae.     

Never born proteins as a test case for ab initio protein structures prediction

The number of natural proteins although large is significantly smaller than the theoretical number of proteins that can be obtained combining the 20 natural amino acids, the so-called “never born proteins” (NBPs). The study of the structure and properties of these proteins allows to investigate the sources of the natural proteins being of unique characteristics or special properties. However the structural study of NPBs can also been intended as an ideal test for evaluating the efficiency of software packages for the ab initio protein structure prediction. In this research, 10.000 three-dimensional structures of proteins of completely random sequence generated according to ROSETTA and FOD model were compared. The results show the limits of these software packages, but at the same time indicate that in many cases there is a significant agreement between the prediction obtained.     

Influence of phosphated cross-linked high amylose on in vitro release of different drugs

The influence of structural characteristics of high amylose cross-linked at different degrees on the release of drugs with important molecular differences, namely sodium diclophenac (SD) and nicotinamide (NI), was assessed in vitro from non-compacted systems. The release profiles were related with classical kinetic mathematical models for better understanding of the release mechanism. An increase in polymer cross-linking degree resulted in longer release time for both drugs, although SD generally was released slower than NI. SD release from samples cross-linked at 2% of basis was driven mainly by Fickian diffusion, while from samples cross-linked at 4% of basis follows anomalous mechanism. Inversely, anomalous mechanism was responsible for NI release from 2% samples and Fickian diffusion from 4% samples. Results suggest that the performance of cross-linked high amylose as excipient for controlled drug release not only depends on cross-linking degree but also is highly influenced by structural characteristics of the drug.