Towards energetically viable asymmetric deprotonations : selectivity at more elevated temperatures with C2-symmetric magnesium bisamides

A novel chiral magnesium bisamide has enabled the development of effective asymmetric deprotonation protocols at substantially more elevated temperatures. This new, structurally simple, C2-symmetric magnesium complex displays excellent levels of asymmetric efficiency and energy reduction in the synthesis of enantioenriched enol silane

The Anti-Inflammatory and Antibacterial Basis of Human Omental Defense: Selective Expression of Cytokines and Antimicrobial Peptides

BACKGROUND: The wound healing properties of the human omentum are well known and have extensively been exploited clinically. However, the underlying mechanisms of these effects are not well understood. We hypothesize that the omentum tissue promotes wound healing via modulation of anti-inflammatory pathways, and because the omentum is rich in adipocytes, the adipocytes may modulate the anti-inflammatory response. Factors released by human omentum may affect healing, inflammation and immune defense. METHODOLOGY: Six human omentum tissues (non obese, free from malignancy, and any other systemic disorder) were obtained during diagnostic laparoscopies having a negative outcome. Healthy oral mucosa (obtained from routine oral biopsies) was used as control. Cultured adipocytes derived from human omentum were exposed to lipopolysaccharide (LPS) (1-50 ng/mL) for 12-72 hours to identify the non-cytotoxic doses. Levels of expression (mRNA and protein) were carried out for genes associated with pro- and anti-inflammatory cytokine responses and antibacterial/antimicrobial activity using qRT-PCR, western blotting, and cell-based ELISA assays. RESULTS: The study shows significant higher levels of expression (mRNA and protein) of several specific cytokines, and antibacterial peptides in the omentum tissues when compared to oral sub-mucosal tissues. In the validation studies, primary cultures of adipocytes, derived from human omentum were exposed to LPS (5 and 10 ng/mL) for 24 and 48 h. The altered expressions were more pronounced in cultured adipocytes cells when exposed to LPS as compared to the omentum tissue. CONCLUSIONS/SIGNIFICANCE: Perhaps, this is the first report that provides evidence of expressional changes in pro- and anti-inflammatory cytokines and antibacterial peptides in the normal human omentum tissue as well as adipocytes cultured from this tissue. The study provides new insights on the molecular and cellular mechanisms of healing and defense by the omentum, and suggests the potential applicability of cultured adipocytes derived from the omentum for future therapeutic applications

A Glial Variant of the Vesicular Monoamine Transporter Is Required To Store Histamine in the Drosophila Visual System

Unlike other monoamine neurotransmitters, the mechanism by which the brain's histamine content is regulated remains unclear. In mammals, vesicular monoamine transporters (VMATs) are expressed exclusively in neurons and mediate the storage of histamine and other monoamines. We have studied the visual system of Drosophila melanogaster in which histamine is the primary neurotransmitter released from photoreceptor cells. We report here that a novel mRNA splice variant of Drosophila VMAT (DVMAT-B) is expressed not in neurons but rather in a small subset of glia in the lamina of the fly's optic lobe. Histamine contents are reduced by mutation of dVMAT, but can be partially restored by specifically expressing DVMAT-B in glia. Our results suggest a novel role for a monoamine transporter in glia that may be relevant to histamine homeostasis in other systems

De Novo Analysis of Transcriptome Dynamics in the Migratory Locust during the Development of Phase Traits

Locusts exhibit remarkable density-dependent phenotype (phase) changes from the solitary to the gregarious, making them one of the most destructive agricultural pests. This phenotype polyphenism arises from a single genome and diverse transcriptomes in different conditions. Here we report a de novo transcriptome for the migratory locust and a comprehensive, representative core gene set. We carried out assembly of 21.5 Gb Illumina reads, generated 72,977 transcripts with N50 2,275 bp and identified 11,490 locust protein-coding genes. Comparative genomics analysis with eight other sequenced insects was carried out to indentify the genomic divergence between hemimetabolous and holometabolous insects for the first time and 18 genes relevant to development was found. We further utilized the quantitative feature of RNA-seq to measure and compare gene expression among libraries. We first discovered how divergence in gene expression between two phases progresses as locusts develop and identified 242 transcripts as candidates for phase marker genes. Together with the detailed analysis of deep sequencing data of the 4th instar, we discovered a phase-dependent divergence of biological investment in the molecular level. Solitary locusts have higher activity in biosynthetic pathways while gregarious locusts show higher activity in environmental interaction, in which genes and pathways associated with regulation of neurotransmitter activities, such as neurotransmitter receptors, synthetase, transporters, and GPCR signaling pathways, are strongly involved. Our study, as the largest de novo transcriptome to date, with optimization of sequencing and assembly strategy, can further facilitate the application of de novo transcriptome. The locust transcriptome enriches genetic resources for hemimetabolous insects and our understanding of the origin of insect metamorphosis. Most importantly, we identified genes and pathways that might be involved in locust development and phase change, and may thus benefit pest management

Fly Photoreceptors Encode Phase Congruency

More than five decades ago it was postulated that sensory neurons detect and selectively enhance behaviourally relevant features of natural signals. Although we now know that sensory neurons are tuned to efficiently encode natural stimuli, until now it was not clear what statistical features of the stimuli they encode and how. Here we reverse-engineer the neural code of Drosophila photoreceptors and show for the first time that photoreceptors exploit nonlinear dynamics to selectively enhance and encode phase-related features of temporal stimuli, such as local phase congruency, which are invariant to changes in illumination and contrast. We demonstrate that to mitigate for the inherent sensitivity to noise of the local phase congruency measure, the nonlinear coding mechanisms of the fly photoreceptors are tuned to suppress random phase signals, which explains why photoreceptor responses to naturalistic stimuli are significantly different from their responses to white noise stimuli

Anti-collagenase, anti-elastase and anti-oxidant activities of extracts from 21 plants

BACKGROUND: Owing to their roles in tissue remodelling in health and disease, several studies have reported investigations on plant extracts as inhibitors of proteinases and as anti-oxidants. METHODS: The anti-ageing and anti-oxidant properties of 23 plant extracts (from 21 plant species) were assessed as anti-elastase and anti-collagenase activities and in selected anti-oxidant assays along with phenolic content. RESULTS: Anti-elastase activities were observed for nine of the extracts with inhibitory activity in the following order: white tea (approximately 89%), cleavers (approximately 58%), burdock root (approximately 51%), bladderwrack (approximately 50%), anise and angelica (approximately 32%). Anti-collagenase activities were exhibited by sixteen plants of which the highest activity was seen in white tea (approximately 87%), green tea (approximately 47%), rose tincture (approximately 41%), and lavender (approximately 31%). Nine plant extracts had activities against both elastase (E) and collagenase (C) and were ranked in the order of white tea (E:89%, C:87%) > bladderwrack (E:50%, C:25%) > cleavers (E:58%, C:7%) > rose tincture (E:22%, C:41%) > green tea (E:10%: C:47%) > rose aqueous (E: 24%, C:26%) > angelica (E:32%, C:17%) > anise (E:32%, C:6%) > pomegranate (E:15%, C:11%).Total phenolic content varied between 0.05 and 0.26 mg gallic acid equivalents (GAE)/mL with the exception of white tea (0.77 mg GAE/mL). For anti-oxidant assessment, the Trolox equivalent anti-oxidant capacity (TEAC) assay revealed activity for all extracts. White tea had the highest activity equivalent to approximately 21 microM Trolox for a 6.25 microg aliquot. In addition, seven extracts exhibited activities = 10 microM Trolox with witch hazel (6.25 microg = 13 microM Trolox) and rose aqueous (6.25 microg = 10 microM Trolox) showing very high activities at low concentrations. A high activity for white tea was also found in the superoxide dismutase (SOD) assay in which it exhibited ~88% inhibition of reduction of nitroblue tetrazolium. High activities were also observed for green tea (86.41%), rose tincture (82.77%), witch hazel (82.05%) and rose aqueous (73.86%). CONCLUSION: From a panel of twenty three plant extracts, some one dozen exhibit high or satisfactory anti-collagenase or anti-elastase activities, with nine having inhibitory activity against both enzymes. These included white tea which was found to have very high phenolic content, along with high TEAC and SOD activities

Advanced imaging in pulmonary hypertension: emerging techniques and applications

Pulmonary hypertension (PH) is a pathophysiological disorder defined by an increase in pulmonary arterial pressure which can occur in multiple clinical conditions. Irrespective of etiology, PH entails a negative impact on exercise capacity and quality of life, and is associated with high mortality particularly in pulmonary arterial hypertension. Noninvasive imaging techniques play an important role in suggesting the presence of PH, providing noninvasive pulmonary pressure measurements, classifying the group of PH, identifying a possibly underlying disease, providing prognostic information and assessing response to treatment. While echocardiography, computed tomography (CT) and ventilation/perfusion scans are an integral part of routine work-up of patients with suspected PH according to current guidelines and across centers, innovative new techniques and applications in the field of PH such as 3D echocardiography, dual-energy CT, 4D flow magnetic resonance imaging (MRI), T1 and extracellular volume fraction mapping, non-contrast-enhanced MRI sequences for perfusion and ventilation assessment, and molecular-targeted positron emission tomography are emerging. This review discusses advanced and emerging imaging techniques in diagnosis, prognostic evaluation and follow-up of patients with PH

A protein related to p21-activated kinase (PAK) that is involved in neurogenesis in the Drosophila adult central nervous system.

AbstractBrains are organized by the developmental processes generating them. The embryonic neurogenic phase of Drosophila melanogaster has been studied in detail at the genetic, cellular and molecular level [1–3]. In contrast, much of what is known of postembryonic brain development has been gathered by neuroanatomical and gene expression studies. The molecular mechanisms underlying cellular diversity and structural organisation in the adult brain, such as the establishment of the correct neuroblast number, the spatial and temporal control of neuroblast proliferation, cell fate determination, and the generation of the precise pattern of neuronal connectivity, are largely unknown. In a screen for viable mutations affecting adult central brain structures, we isolated the mushroom bodies tiny (mbt) gene of Drosophila, which encodes a protein related to p21-activated kinase (PAK). We show that mutations in mbt primarily interfere with the generation or survival of the intrinsic cells (Kenyon cells) of the mushroom body, a paired neuropil structure in the adult brain involved in learning and memory [4–6]