Attachment security in very low birth weight infants.

34 infants of very low birth weight (VLBW) and a comparison group of 40 full-term infants were observed in the Strange Situation of M. D. Ainsworth et al (1978) at 14 and 19 mo and observed in the home at 14 mo of age, using E. Waters's (1995) Attachment Q-set. Results indicated that at 14 mo VLBW infants were more likely than the full-term infants to be insecurely attached when rated using the Q-set but not when using the Strange Situation. However, at 19 mo VLBW infants were also more likely than full-term infants to be insecurely attached in the Strange Situation assessment. There were no associations between the Q-set and Strange Situation measures of attachment security. These results are discussed in terms of the social-emotional development of VLBW infants. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of chain length on formation of a double-layer structure of Z-(Gly-Pro-Gly)n-OMe oligotripeptides

Effect of chain length on the formation of the double-layered sheet in synthetic oligotripeptides Z-(Gly-Pro-Gly)n-OMe (n = 1,2,3,4) in the solid state has been studied by the IR-spectroscopy method. The major spectral features characteristic for the polymer structure was found in the oligomer spectra beginning with that of hexapeptide (n = 2). So a minimum peptide length when peptide chains are still able to adopt the double-layered sheet conformation in the solid state includes two triplets. The result is similar to that we have revealed early by investigation of the collagen-like triple helix formation in the oligomer series Z-(Gly-Pro-Pro)n-OMe. The double-layered sheet structure of the hexapeptide was found completely regular as that of the polymer. So the formation of the double-layered sheet structure unlike the formation of the triple-helical structure occurs at once without gradual ordering of interpeptide bonds and molecular packing by further increasing of the triplet number in oligomer chains. Additional information concerning specific incorporation of bound water in the double-layered sheet and water influence on peptide packing has been derived from analyses of hydration effect on the oligotripeptide IR-spectra especially on the components of the amide I band.     

Particle swarm optimization with deep learning for human action recognition

Multimedia Tools and Applications - A novel method for human action recognition using a deep learning network with features optimized using particle swarm optimization is proposed. The binary...     

Robust speech recognition using spatial-temporal feature distribution characteristics

Histogram equalization (HEQ) is one of the most efficient and effective techniques that have been used to reduce the mismatch between training and test acoustic conditions. However, most of the current HEQ methods are merely performed in a dimension-wise manner and without allowing for the contextual relationships between consecutive speech frames. In this paper, we present several novel HEQ approaches that exploit spatial-temporal feature distribution characteristics for speech feature normalization. The automatic speech recognition (ASR) experiments were carried out on the Aurora-2 standard noise-robust ASR task. The performance of the presented approaches was thoroughly tested and verified by comparisons with the other popular HEQ methods. The experimental results show that for clean-condition training, our approaches yield a significant word error rate reduction over the baseline system, and also give competitive performance relative to the other HEQ methods compared in this paper.     

Expression of functionally active hyman cytochrome P-450c21 (CYPXXIA2) in Escherichia coli and single-stage purification of it using metal-affinity chromatography

Active human cytochrome P-450c21 was expressed in Escherichia coli and purified to homogeneity. To increase expression, cDNA encoding for the N-terminal fragment of cytochrome P-450c21 was modified. Four histidine codons were added to cDNA encoding for the C-terminus of the protein; thus, recombinant protein could have been rapidly and effectively purified by metal-affinity chromatography. Modified human cytochrome P-450c21 was expressed (40-50 nmoles/l of culture according to spectrophotometry) which was able to bind to bacterial membrane. Modifications of N- and C-terminal regions of cytochrome P-450c21 did not change Km and Vmax for hydroxylation of progesterone and 17 alpha-hydroxyprogesterone in reconstituted system. Recombinant cytochrome P-450c21 was purified to apparent homogeneity from Escherichia coli membrane extract by metal-affinity chromatography. Purified cytochrome P-450c21 migrates as a single 54 kD band on polyacrylamide gel and exhibits type I spectral changes during interaction with progesterone and 17 alpha-hydroxyprogesterone. Activity of purified cytochrome P-450c21 was reconstituted with mouse liver microsomal NADPH-cytochrome P-450-reductase and NADPH-regenerating system. Purified enzyme had Km 12.2 and 3.21 microM and Vmax 192.9 and 198 nmoles/min/nmole of P-450c21 for 17 alpha-hydroxyprogesterone and progesterone, respectively. According to titration spectra, dissociation constants for progesterone and 17 alpha-hydroxy-progesterone were 14.7 and 31.1 microM, respectively.     

Mast Cell Proteases Tryptase and Chymase Induce Migratory and Morphological Alterations in Bronchial Epithelial Cells

Chronic respiratory diseases are often characterized by impaired epithelial function and remodeling. Mast cells (MCs) are known to home into the epithelium in respiratory diseases, but the MC-epithelial interactions remain less understood. Therefore, this study aimed to investigate the effect of MC proteases on bronchial epithelial morphology and function. Bronchial epithelial cells were stimulated with MC tryptase and/or chymase. Morphology and epithelial function were performed using cell tracking analysis and holographic live-cell imaging. Samples were also analyzed for motility-associated gene expression. Immunocytochemistry was performed to compare cytoskeletal arrangement. Stimulated cells showed strong alterations on gene, protein and functional levels in several parameters important for maintaining epithelial function. The most significant increases were found in cell motility, cellular speed and cell elongation compared to non-stimulated cells. Also, cell morphology was significantly altered in chymase treated compared to non-stimulated cells. In the current study, we show that MC proteases can induce cell migration and morphological and proliferative alterations in epithelial cells. Thus, our data imply that MC release of proteases may play a critical role in airway epithelial remodeling and disruption of epithelial function.     

SNAP-Tag-Targeted MRI-Fluorescent Multimodal Probes

Magnetic resonance imaging (MRI) is a powerful imaging modality, widely employed in research and clinical settings. However, MRI images suffer from low signals and a lack of target specificity. We aimed to develop a multimodal imaging probe to detect targeted cells by MRI and fluorescence microscopy. We synthesized a trifunctional imaging probe consisting of a SNAP-tag substrate for irreversible and specific labelling of cells, cyanine dyes for bright fluorescence, and a chelated Gd^III molecule for enhancing MRI contrast. Our probes exhibit specific and efficient labelling of genetically defined cells (expressing SNAP-tag at their membrane), bright fluorescence and MRI signal. Our synthetic approach provides a versatile platform for the production of multimodal imaging probes, particularly for light microscopy and MRI.