Developmental psychopathology: recent advances and future challenges

The integrative field of developmental psychopathology is having a huge impact on our understanding of human health and behavior. In this paper, I use the example of children's early stress exposure to illustrate how developmental psychopathologists now tend to deemphasize diagnostic categories and, instead, emphasize the social and biological contexts, events and circumstances that have created opportunities for maladaptive responses and health problems in youth. This example shows that developmental psychopathology is increasing understanding of how children develop the abilities that allow them to cope effectively with challenges and what leads to failures in development of these abilities. Integrating research about the neurobiology of learning may prove to be a powerful future direction to understand how the environment regulates behavior. Learning processes become increasingly intricate and fine‐tuned as relevant neuroanatomical systems develop, and as the range, complexity and amount of environmental information increases for the developing child. A focus on these processes allows psychopathologists to formulate questions about which neural mechanisms children use to process information, how these mechanisms are themselves shaped by social context, why adverse social environments confer risk for children, and, perhaps, what sorts of neutrally informed interventions might remediate the deficits in self‐regulation that underlie common psychopathologies.     

Asymmetric synthesis of chiral amines with omega-transaminase.

The asymmetric synthesis of chiral amines using prochiral ketones was carried out with (S)-specific omega-transaminase (omega-TA) from Vibrio fluvialis JS17. This reaction is inhibited severely by both products, (S)-amine and deaminated ketone. In addition, thermodynamic equilibrium strongly favored the reverse reaction. L-Alanine proved to be the best amino donor based on easy removal of the products. Optimal pH of the reactions with both whole cells and cell-free extract was 7. Amino acceptor reactivities of ketone substrates and reaction profiles of the asymmetric synthesis showed that the initial rate as well as the reaction yield were lower when the resulting (S)-amine from a prochiral ketone substrate was a more reactive amino donor. The yield could be increased dramatically by removing pyruvate, which is a more inhibitory product than (S)-alpha-methylbenzylamine [(S)-alpha-MBA] when acetophenone and L-alanine are used as an amino acceptor and donor, respectively. The removal of pyruvate was carried out by incorporating lactate dehydrogenase (LDH) in cell-free extract or by using whole cells. The whole cell reaction yielded a much better result. When 25 mM benzylacetone and 30 mM acetophenone were used as an amino acceptor with 300 mM L-alanine, 90.2% and 92.1% of the reaction yields after 1 day were obtained with whole cells, respectively. Enantiomeric excesses of both (S)-alpha-MBA and (S)-1-methyl-3-phenylpropylamine [(S)-MPPA] were all above 99%.     

Membrane protein solubilization: recent advances and challenges in solubilization of serotonin1A receptors

Solubilization of integral membrane proteins is a process in which the proteins and lipids that are held together in native membranes are suitably dissociated in a buffered detergent solution. The controlled dissociation of the membrane results in formation of small protein and lipid clusters that remain dissolved in the aqueous solution. Effective solubilization and purification of membrane proteins, especially heterologously-expressed proteins in mammalian cells in culture, in functionally active forms represent important steps in understanding structure-function relationship of membrane proteins. In this review, critical factors determining functional solubilization of membrane proteins are highlighted with the solubilization of the serotonin 1A receptor taken as a specific example.     

Peroxisome biogenesis: recent advances

In recent years, it has become evident that peroxisomes form part of the endomembrane system. Peroxisomes can form from the ER via a maturation process and they can multiply by growth and division, whereby the ER provides membrane for growth and ongoing fission (Figure 1). Until very recently, it was widely accepted that most peroxisomal membrane proteins (PMPs) insert directly into peroxisomes, whereas a small subset of PMPs traffic via the ER. In this minireview, we focus mainly on PMP biogenesis, and highlight recent advances in peroxisomal matrix protein import, fission and segregation in yeast.     

Polyamines and environmental challenges: recent development

In this review, we will try to summarize some recent data concerning the changes in polyamine metabolism (biosynthesis, catabolism and regulation) in higher plants subjected to a wide array of environmental stress conditions and to describe and discuss some of the new advances concerning the different proposed mechanisms of polyamine action implicated in plant response to environmental challenges. All the data support the view that putrescine and derived polyamines (spermidine, spermine, long-chained polyamides) may have several functions during environmental challenges. In several systems (except during hypoxia, and chilling tolerance of wheat and rice) an induction of polyamines (spermidine, spermine) not putrescine accumulation, may confer a stress tolerance. In several cases stress tolerance is associated with the production of conjugated and bound polyamines and stimulation of polyamine oxidation. In several environmental challenges (osmotic-stress, salinity, hypoxia, environmental pollutants) recent results indicate that both arginine decarboxylase and ornithine decarboxylase are required for the synthesis of putrescine and polyamines (spermidine and spermine). Under osmotic and salt-stresses a production of cadaverine is observed in plants. A new study demonstrates that under salt-stress putrescine catabolism (via diamine oxidase) can contribute to proline (a compatible osmolyte) accumulation.     

Fluorescence imaging in vivo: recent advances

In vivo fluorescence imaging uses a sensitive camera to detect fluorescence emission from fluorophores in whole-body living small animals. To overcome the photon attenuation in living tissue, fluorophores with long emission at the near-infrared (NIR) region are generally preferred, including widely used small indocarbocyanine dyes. The list of NIR probes continues to grow with the recent addition of fluorescent organic, inorganic and biological nanoparticles. Recent advances in imaging strategies and reporter techniques for in vivo fluorescence imaging include novel approaches to improve the specificity and affinity of the probes and to modulate and amplify the signal at target sites for enhanced sensitivity. Further emerging developments are aiming to achieve high-resolution, multimodality and lifetime-based in vivo fluorescence imaging.     

Dientamoebiasis: clinical importance and recent advances

Dientamoeba fragilis, an unusual single-celled parasite that was described first in 1918, is found worldwide in the gastrointestinal tract of humans. D. fragilis has emerged from obscurity recently because it is now recognized as a common cause of chronic diarrhoea and is treatable with drugs. Recent molecular studies have described D. fragilis as having two genotypes. Diagnostic tests, based on conventional and real-time PCR, have been developed that will provide a rapid, sensitive and specific diagnosis of D. fragilis. These tests will also aid the elucidation of the host distribution and the life cycle of this pathogen.     

Thyroglobulin structure and function: recent advances

Thyroglobulin is a large-size iodoglycoprotein specific to thyroid tissue and is the substrate for the synthesis of thyroid hormones, thyroxine and 3,5,3'-triiodothyronine. Recent studies, which greatly benefited from recombinant DNA methodologies, improved the knowledge of several structural features of this dimeric protein and permitted insights into some structure-function relationships. Analysis-function of the primary structure of the human thyroglobulin monomer revealed several main characteristics: 1) 3 types of internal homologies; 2) extensive homology with the bovine thyroglobulin monomer and known partial sequences in the thyroglobulins of other mammalian species; 3) significant homologies with 2 other non-thyroid proteins (acetylcholinesterase and the invariant chain of the Ia class II histocompatibility antigen); 4) a terminal localization of the hormonogenic sites at both ends of the monomer. Current studies aim at determining conformational characteristics, understanding the molecular mechanisms of thyroid hormone formation and unraveling those interactions which in the thyroid cell and the thyroid follicle will permit this large pro-hormone to synthesize and release a few small thyroid hormone molecules. A more precise knowledge of this molecule in higher vertebrates and during evolution would impart valuable information concerning thyroid pathology, since thyroglobulin has been implicated in some genetic and in autoimmune thyroid diseases.     

Aerobic granular sludge: recent advances

Aerobic granulation, a novel environmental biotechnological process, was increasingly drawing interest of researchers engaging in work in the area of biological wastewater treatment. Developed about one decade ago, it was exciting research work that explored beyond the limits of aerobic wastewater treatment such as treatment of high strength organic wastewaters, bioremediation of toxic aromatic pollutants including phenol, toluene, pyridine and textile dyes, removal of nitrogen, phosphate, sulphate and nuclear waste and adsorption of heavy metals. Despite this intensive research the mechanisms responsible for aerobic granulation and the strategy to expedite the formation of granular sludge, and effects of different operational and environmental factors have not yet been clearly described. This paper provides an up-to-date review on recent research development in aerobic biogranulation technology and applications in treating toxic industrial and municipal wastewaters. Factors affecting granulation, granule characterization, granulation hypotheses, effects of different operational parameters on aerobic granulation, response of aerobic granules to different environmental conditions, their applications in bioremediations, and possible future trends were delineated. The review attempts to shed light on the fundamental understanding in aerobic granulation by newly employed confocal laser scanning microscopic techniques and microscopic observations of granules.