Discovery of 2-substituted benzoxazole carboxamides as 5-HT3 receptor antagonists

A new class of 2-substituted benzoxazole carboxamides are presented as potent functional 5-HT(3) receptor antagonists. The chemical series possesses nanomolar in vitro activity against human 5-HT(3)A receptors. A chemistry optimization program was conducted and identified 2-aminobenzoxazoles as orally active 5-HT(3) receptor antagonists with good metabolic stability. These novel analogues possess drug-like characteristics and have potential utility for the treatment of diseases attributable to improper 5-HT(3) receptor function, especially diarrhea predominant irritable bowel syndrome (IBS-D).     

mTRAQ‐based quantification of potential endometrial carcinoma biomarkers from archived formalin‐fixed paraffin‐embedded tissues

Formalin‐fixed paraffin‐embedded (FFPE) tissues are the primary and preferred medium for archiving patients' samples. Here we demonstrate relative quantifications of protein biomarkers in extracts of laser microdissected epithelial cells from FFPE endometrial carcinoma tissues versus those from normal proliferative endometria by means of targeted proteomic analyses using LC–multiple reaction monitoring (MRM) MS with MRM Tags for Relative and Absolute Quantitation (mTRAQ) labeling. Comparable results of differential expressions for pyruvate kinase isoform M2 (PK‐M2) and polymeric Ig receptor were observed between analyses on laser microdissected epithelial cells from FFPE tissues and corresponding homogenates from frozen tissues of the same individuals that had previously been analyzed and reported. We also identified PK‐M2 in the normal proliferative phase of the endometrium. Other biomarkers in addition to PK‐M2 and polymeric Ig receptor were also observed but not consistently and/or were at levels below the threshold for quantification.     

Modeling Nymphoides architecture: A morphological analysis of Nymphoides aquatica (Menyanthaceae)

? Premise of the study: Species in the aquatic genus Nymphoides have inflorescences that appear to arise from the petioles of floating leaves. The inflorescence-floating leaf complex can produce vegetative propagules and/or additional inflorescences and leaves. We analyzed the morphology of N. aquatica to determine how this complex relates to whole plant architecture and whether whole plant growth is sympodial or monopodial. ? Methods: We used dissections, measurements, and microscopic observations of field-collected plants and plants cultivated for 2 years in outdoor tanks in south Florida, USA. ? Key results: Nymphoides aquatica had a submerged plagiotropic rhizome that produced floating leaves in an alternate/spiral phyllotaxy. Rhizomes were composed of successive sympodial units that varied in the number of leaves produced before the apex terminated. The basic sympodial unit had a prophyll that subtended a renewal-shoot bud, a short-petioled leaf (SPL) with floating lamina, and an inflorescence; the SPL axillary bud expanded as a vegetative propagule. Plants produced either successive basic sympodial units or expanded sympodia that intercalated long-petioled leaves between the prophyll and the SPL. ? Conclusions: Nymphoides aquatica grows sympodially, forming a rhizome composed of successive basic sympodia and expanded sympodial units. Variations on these types of sympodial growth help explain the branching patterns and leaf morphologies described for other Nymphoides species. Monitoring how these two sympodial phases are affected by water depth provides an ecologically meaningful way to assess N. aquatica's responses to altered hydrology.     

Dexfenfluramine protects against pulmonary hypertension in rats.

Dexfenfluramine (Dex), an appetite suppressant and serotonin reuptake inhibitor, is associated with pulmonary vascular disease (PVD) in some patients. The variability might be related to undetermined genetic abnormalities interacting with factors such as gender, weight loss, and vascular injury. We, therefore, assessed the effect of Dex (5 mg. kg(-1). day(-1)) in female obese rats, designated JCR:LA-cp or cp/cp; in lean rats, designated (+/?); and in normal Sprague-Dawley (S-D) rats under control conditions or after endothelial injury induced by monocrotaline (60 mg/kg). Pulmonary arterial pressure, right ventricular hypertrophy, percent medial wall thickness of muscular arteries, and muscularization of peripheral arteries were assessed as indexes of PVD. Although Dex reduced weight gain in cp/cp and S-D rats (P < 0.05 for both), it did not cause PVD. Moreover, PVD in S-D rats after monocrotaline injection was paradoxically ameliorated by Dex (P < 0.05) despite induction of pulmonary artery elastase (P < 0.05), which we showed is critical in inducing experimental PVD. Thus it is possible that Dex is concomitantly offsetting the sequelae of elastase activity.     

Proteomic analysis reveals differences between Vitis vinifera L. cv. Chardonnay and cv. Cabernet Sauvignon and their responses to water deficit and salinity

The impact of water deficit and salt stress on two important wine grape cultivars, Chardonnay and Cabernet Sauvignon, was investigated. Plants were exposed to increasing salinity and water deficit stress over a 16 d time period. Measurements of stem water potentials, and shoot and leaf lengths indicated that Chardonnay was more tolerant to these stresses than Cabernet Sauvignon. Shoot tips were harvested every 8 d for proteomic analysis using a trichloroacetic acid/acetone extraction protocol and two-dimensional gel electrophoresis. Proteins were stained with Coomassie Brilliant Blue, quantified, and then 191 unique proteins were identified using matrix-assisted laser desorption ionization time of flight/time of flight mass spectrometry. Peptide sequences were matched against both the NCBI nr and TIGR Vitis expressed sequence tag (EST) databases that had been implemented with all public Vitis sequences. Approximately 44% of the protein isoforms could be identified. Analysis of variance indicated that varietal difference was the main source of protein expression variation (40%). In stressed plants, reduction of the amount of proteins involved with photosynthesis, protein synthesis, and protein destination was correlated with the inhibition of shoot elongation. Many of the proteins up-regulated in Chardonnay were of unclassified or of unknown function, whereas proteins specifically up-regulated in Cabernet Sauvignon were involved in protein metabolism.     

Crystallographic and mutational studies of Mycobacterium tuberculosis recA mini-inteins suggest a pivotal role for a highly conserved aspartate residue

The 440 amino acid Mtu recA intein consists of independent protein-splicing and endonuclease domains. Previously, removal of the central endonuclease domain of the intein, and selection for function, generated a 168 residue mini-intein, DeltaI-SM, that had splicing activity similar to that of the full-length, wild-type protein. A D422G mutation (DeltaI-CM) increased C-terminal cleavage activity. Using the DeltaI-SM mini-intein structure (presented here) as a guide, we previously generated a highly active 139 residue mini-intein, DeltaDeltaI(hh)-SM, by replacing 36 amino acid residues in the residual endonuclease loop with a seven-residue beta-turn from the autoprocessing domain of Hedgehog protein. The three-dimensional structures of DeltaI-SM, DeltaDeltaI(hh)-SM, and two variants, DeltaDeltaI(hh)-CM and DeltaDeltaI(hh), have been determined to evaluate the effects of the minimization on intein integrity and to investigate the structural and functional consequences of the D422G mutation. These structural studies show that Asp422 is capable of interacting with both the N and C termini. These interactions are lacking in the CM variant, but are replaced by contacts with water molecules. Accordingly, additional mutagenesis of residue 422, combined with mutations that isolate N-terminal and C-terminal cleavage, showed that the side-chain of Asp422 plays a role in both N and C-terminal cleavage, thereby suggesting that this highly conserved residue regulates the balance between the two reactions.     

The influence of macrofouling on the corrosion behaviour of API 5L X65 carbon steel

Seawater is a complex corrosive system, and biofouling is one of the factors that influences corrosion processes. The behaviour of corrosion associated with the development of macrofouling was investigated during the first 6 months of the successional process. Three treatments were compared: the 'Control' treatment (absence of macrofouling); 'Community' treatment, and 'Barnacle' treatment, where other macroorganisms were excluded. In the Community treatment, the dominant organisms were filamentous macroalgae (23.73%), barnacles (17.51%), hydroids (16.96%) and encrusting bryozoans (9.58%). In the Barnacle treatment, the cover varied between 39.38% and 62.50%. The corrosion potential ranged from -665.75 to -517.50 mV(Ag/AgC l((KCl))) and could not be associated with fouling development. The highest corrosion rate in the control suggests that macrofouling provides a protection against mass loss. The highest percentage of localised attacks was found in the Community treatment. This may indicate that not only barnacles, but also other organisms induce localised corrosion.     

TPEN selectively eliminates lymphoblastic B cells from bone marrow pediatric acute lymphoblastic leukemia patients

BioMetals - B-cell acute lymphoblastic leukemia (B-ALL) is a hematologic disorder characterized by the abnormal proliferation and accumulation of immature B-lymphoblasts arrested at various stages...     

Coloration,Paternity, and Assortative Mating in Western Bluebirds

Coloration in birds can act as an important sexual signal in males, yet in many species, both sexes display bright colors. Social selection may account for this pattern, with more brightly colored individuals pairing together on the best territories. Mutual mate choice may also explain this, as males investing a great deal of parental care in the offspring should be choosy about their social mates. It is less clear whether this pattern of mate choice can apply to extra‐pair partners as well. We examined western bluebirds (Sialia mexicana) to determine whether more colorful individuals tended to pair with one another, both in social pairs and between females and their extra‐pair partners. Both male and female western bluebirds display both UV‐blue structural plumage and a melanin‐based chestnut breast patch, although females are duller than males. Social pairs mated assortatively with regard to UV‐blue brightness, but not chestnut coloration. There was no evidence that extra‐pair partners mated assortatively, but males with brighter UV‐blue coloration had fewer extra‐pair offspring in their nests. Older males were more successful at siring extra‐pair offspring, despite displaying no differences in coloration compared to younger males. Coloration did not play a role in determining extra‐pair male success. These results suggest that coloration plays a role in the formation of social pairs, but not mate choice for extra‐pair partners.     

Post-translational environmental switch of RadA activity by extein–intein interactions in protein splicing

Post-translational control based on an environmentally sensitive intervening intein sequence is described. Inteins are invasive genetic elements that self-splice at the protein level from the flanking host protein, the exteins. Here we show in Escherichia coli and in vitro that splicing of the RadA intein located in the ATPase domain of the hyperthermophilic archaeon Pyrococcus horikoshii is strongly regulated by the native exteins, which lock the intein in an inactive state. High temperature or solution conditions can unlock the intein for full activity, as can remote extein point mutations. Notably, this splicing trap occurs through interactions between distant residues in the native exteins and the intein, in three-dimensional space. The exteins might thereby serve as an environmental sensor, releasing the intein for full activity only at optimal growth conditions for the native organism, while sparing ATP consumption under conditions of cold-shock. This partnership between the intein and its exteins, which implies coevolution of the parasitic intein and its host protein may provide a novel means of post-translational control.