Hydrophobic proteins of lamellated osmiophilic bodies isolated from pig lung.

1. In addition to proteins that are insoluble in organic solvents, lamellated bodies isolated from pig lung and surfactant prepared from bronchopulmonary lavage fluid contain another group of proteins that are extracted together with lipid into the organic phase. 2. These hydrophobic proteins constitute about 40% of the total protein of lamellated bodies and about 13% of the total protein of surfactant isolated from lavage fluid, whereas less than 1% of the total protein of pig lung microsomal fraction and mitochondria is extracted by organic solvents. 3. The hydrophobic proteins of lamellated bodies were separated into four fractions and freed from phospholipid by chromatographic procedures. Their apparent molecular weights vary between 11 500 and 16 500, they contain 72--79% of hydrophobic residues and 16--22% of sulphur-containing amino-acids, and leucine is the major N-terminal amino acid in each case.     

Characterization of Overexpressed cDNAs Isolated from a Hormone-Autonomous, Radiation-Induced Tumor Tissue Line of Arabidopsis thaliana

To investigate the molecular mechanisms of hormonal control of growth, we constructed a subtracted cDNA library enriched for sequences expressed more in a hormone-autonomous, radiation-induced tumor tissue line of Arabidopsis thaliana than in normal, hormone-dependent callus. Ten cDNA clones, which are expressed 1.3- to 10-fold more in the tumor line, were isolated and partially characterized. The clones differ greatly in their level of expression in tumor tissue and in their pattern of expression in plant organs. Southern blot hybridization and sequence analysis showed that this group contains three pairs of closely related clones. Northern blot analysis indicates that one pair of clones represents two members of a gene family that are expressed in different plant organs. One of the isolated sequences shows strong sequence similarity to a cDNA encoding a lipid transfer protein. Two sequences are highly similar to those of previously described membrane channel proteins but have different organ specificities. Two other cDNAs have significant sequence similarity to glycine-rich proteins and hydroxy-proline-rich glycoproteins. When used to probe Southern blots, none of the cDNAs identified polymorphisms between tumor and callus DNA, which might be expected if their overexpression were due to local genome rearrangements induced by radiation. The diversity observed among these 10 clones suggests that some are likely to be involved in tumorous growth and not simply specific to a certain cell or tissue type present in the tumor.     

Doppler optical coherence tomography for measuring flow in engineered tissue

The engineering of human tissue represents a major paradigm shift in clinical medicine. Early embodiments of tissue engineering are currently being taken forward to the clinic by production methods that are essentially extensions of laboratory manual procedures. However, to achieve the status of routine large-scale clinical practice, automation and scale-out processes are required. This in turn will require the development of reliable on-line monitoring and control systems. This paper examines one demand of crucial importance, namely the real time in vitro monitoring of the flow characteristics through growing tissue since this has a complex interrelationship. Doppler optical coherence tomography (DOCT) is a recently developed imaging technique for studying the rheological properties of tissues in vivo. Capable of non-invasive imaging in real time with high resolution, it is potentially ideal for the continuous monitoring of engineered tissues in vitro. As a base line, the current status of DOCT in vivo is therefore reviewed. This paper also reports the first preliminary use of DOCT in tissue engineering. The application described involves the imaging of a fully developed laminar flow through a combined tissue fabrication/bioreactor with a tissue-engineered construct (substitute blood vessel) in situ.     

Highly syntenic regions in the genomes of soybean, <Emphasis Type="Italic">Medicago truncatula</Emphasis>, and <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis>

Background  

Recent genome sequencing enables mega-base scale comparisons between related genomes. Comparisons between animals, plants, fungi, and bacteria demonstrate extensive synteny tempered by rearrangements. Within the legume plant family, glimpses of synteny have also been observed. Characterizing syntenic relationships in legumes is important in transferring knowledge from model legumes to crops that are important sources of protein, fixed nitrogen, and health-promoting compounds.     

Eosinophil peroxidase produces hypobromous acid in the airways of stable asthmatics

Eosinophil peroxidase and myeloperoxidase use hydrogen peroxide to produce hypobromous acid and hypochlorous acid. These powerful oxidants may damage the lungs if they are produced as part of the inflammatory response in asthma. The aim of this study was to determine if peroxidases generate hypohalous acids in the airways of individuals with stable asthma, and if they affect lung function. Sputum was induced from patients with mild to moderate asthma and from healthy controls. Eosinophil peroxidase, myeloperoxidase, chlorinated and brominated tyrosyl residues, and protein carbonyls were measured in sputum supernatants. Eosinophil peroxidase protein was significantly elevated in asthmatic subjects whereas myeloperoxidase protein was not. There was significantly more 3-bromotyrosine (Br-Tyr) in proteins from the sputum of asthmatics compared to controls (0.79 vs. 0.23 mmol Br-Tyr/mol Tyr; medians p < .0001). Levels of 3-chlorotyrosine (0.23 vs. 0.14 mmol Cl-Tyr/mol Tyr; medians p = .11) and protein carbonyls (0.347 vs. 0.339 nmol/mg protein; medians p = .56) were not significantly increased in asthmatics. Levels of 3-bromotyrosine were strongly correlated with eosinophil peroxidase protein (r = 0.79, p < .0001). There were no significant correlations between the markers of oxidative stress and lung function. We conclude that eosinophil peroxidase produces substantial amounts of hypobromous acid in the airways of stable asthmatics. Although this highly reactive oxidant is a strong candidate for exacerbating inflammatory tissue damage in the lung, its role in asthma remains uncertain.     

CD40 signaling and Alzheimer's disease pathogenesis

The interaction between CD40 and its cognate ligand, CD40 ligand, is a primary regulator of the peripheral immune response, including modulation of T lymphocyte activation, B lymphocyte differentiation and antibody secretion, and innate immune cell activation, maturation, and survival. Recently, we and others have identified CD40 expression on a variety of CNS cells, including endothelial cells, smooth muscle cells, astroglia and microglia, and have found that, on many of these cells, CD40 expression is enhanced by pro-inflammatory stimuli. Importantly, the CD40–CD40 ligand interaction on microglia triggers a series of intracellular signaling events that are discussed, beginning with Src-family kinase activation and culminating in microglial activation as evidenced by tumor necrosis factor- secretion. Based on the involvement of microglial activation and brain inflammation in Alzheimer's disease pathogenesis, we have investigated co-stimulation of microglia, smooth muscle, and endothelial cells with CD40 ligand in the presence of low doses of freshly solubilized amyloid-β peptides. Data reviewed herein show that CD40 ligand and amyloid-β act synergistically to promote pro-inflammatory responses by these cells, including secretion of interleukin-1β by endothelial cells and tumor necrosis factor- by microglia. As these cytokines have been implicated in neuronal injury, a comprehensive model of pro-inflammatory CD40 ligand and amyloid-β initiated Alzheimer's disease pathogenesis (mediated by multiple CNS cells) is proposed.     

Tmem26 is dynamically expressed during palate and limb development but is not required for embryonic survival

The Tmem26 gene encodes a novel protein that we have previously shown to be regulated by hedgehog signalling in the mouse limb. We now report that Tmem26 expression is spatially and temporally restricted in other regions of the mouse embryo, most notably the facial primordia. In particular, Tmem26 expression in the mesenchyme of the maxillary and nasal prominences is coincident with fusion of the primary palate. In the secondary palate, Tmem26 is expressed in the palatal shelves during their growth and fusion but is downregulated once fusion is complete. Expression was also detected at the midline of the expanding mandible and at the tips of the eyelids as they migrate across the cornea. Given the spatio-temporally restricted expression of Tmem26, we sought to uncover a functional role in embryonic development through targeted gene inactivation in the mouse. However, ubiquitous inactivation of Tmem26 led to no overt phenotype in the resulting embryos or adult mice, suggesting that TMEM26 function is dispensable for embryonic survival.     

Multiplex Detection of Bacteria in Complex Clinical and Environmental Samples using Oligonucleotide-coupled Fluorescent Microspheres

Bacterial vaginosis (BV) is a recurring polymicrobial syndrome that is characterized by a change in the "normal" microbiota from Lactobacillus-dominated to a microbiota dominated by a number of bacterial species, including Gardnerella vaginalis, Atopobium vaginae, and others^1-3. This condition is associated with a range of negative health outcomes, including HIV acquisition⁴, and it can be difficult to manage clinically⁵. Furthermore, diagnosis of BV has relied on the use of Gram stains of vaginal swab smears that are scored on various numerical criteria^6,7. While this diagnostic is simple, inexpensive, and well suited to resource-limited settings, it can suffer from problems related to subjective interpretations and it does not give a detailed profile of the composition of the vaginal microbiota⁸. Recent deep sequencing efforts have revealed a rich, diverse vaginal microbiota with clear differences between samples taken from individuals that are diagnosed with BV compared to those individuals that are considered normal^9,10, which has resulted in the identification of a number of potential targets for molecular diagnosis of BV^11,12. These studies have provided a wealth of useful information, but deep sequencing is not yet practical as a diagnostic method in a clinical setting. We have recently described a method for rapidly profiling the vaginal microbiota in a multiplex format using oligonucleotide-coupled fluorescent beads with detection on a Luminex platform¹³. This method, like current Gram stain-based methods, is rapid and simple but adds the additional advantage of exploiting molecular knowledge arising from sequencing studies in probe design. This method therefore provides a way to profile the major microorganisms that are present in a vaginal swab that can be used to diagnose BV with high specificity and sensitivity compared to Gram stain while providing additional information on species presence and abundance in a semi-quantitative and rapid manner. This multiplex method is expandable well beyond the range of current quantitative PCR assays for particular organisms, which is currently limited to 5 or 6 different assays in a single sample¹⁴. Importantly, the method is not limited to the detection of bacteria in vaginal swabs and can be easily adapted to rapidly profile nearly any microbial community of interest. For example, we have recently begun to apply this methodology to the development of diagnostic tools for use in wastewater treatment plants.Download video file.^{(68M, mov)}