Involvement of phospholipase C signaling in melanoma cell-induced endothelial junction disassembly

In this study, we report a phospholipase C (PLC)-mediated mechanism for the redistribution of interendothelial adherens junctions in response to melanoma cell contacts with the endothelium. We demonstrated that contact of melanoma cells to human umbilical vein endothelial cells (HUVEC) triggered rapid endothelial [Ca2+]i response through PLC-IP3 pathway. In addition, alternation of endothelial adherens junctions following contact of melanoma cells was evidenced by the changes in immunological staining patterns of vascular endothelial (VE)-cadherin. A PLC inhibitor, {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 was shown to significantly diminish [Ca2+]i response and reduce the occurrence of melanoma cell–induced VE-cadherin reorganization. Moreover, inhibition of PLC attenuated melanoma cell transendothelial migration. However, melanoma cell-associated VE-cadherin breakdown was not sensitive to Ly294002, an inhibitor of phosphatidylinositol-3-kinase (PI3K), whereas inhibition of PI3K resulted in a reduction of melanoma cell transmigration. Taken together, our findings implicate that by inducing the PLC-Ca2+ signaling pathway, melanoma cells disrupt EC junctions to breach the endothelium and promote transvascular homing of tumor cells

Voice Conversion Based on Cross-Domain Features Using Variational Auto Encoders

An effective approach to non-parallel voice conversion (VC) is to utilize deep neural networks (DNNs), specifically variational auto encoders (VAEs), to model the latent structure of speech in an unsupervised manner. A previous study has confirmed the ef- fectiveness of VAE using the STRAIGHT spectra for VC. How- ever, VAE using other types of spectral features such as mel- cepstral coefficients (MCCs), which are related to human per- ception and have been widely used in VC, have not been prop- erly investigated. Instead of using one specific type of spectral feature, it is expected that VAE may benefit from using multi- ple types of spectral features simultaneously, thereby improving the capability of VAE for VC. To this end, we propose a novel VAE framework (called cross-domain VAE, CDVAE) for VC. Specifically, the proposed framework utilizes both STRAIGHT spectra and MCCs by explicitly regularizing multiple objectives in order to constrain the behavior of the learned encoder and de- coder. Experimental results demonstrate that the proposed CD- VAE framework outperforms the conventional VAE framework in terms of subjective tests.Comment: Accepted to ISCSLP 201

A Study on the Growth and Formation of Single Person Households and Their Housing Decisions in Taiwan

The number of single person households has dramatically increased in Taiwan in the past several decades as it has elsewhere in the world, but this phenomenon has been largely neglected in the literature. This research explores the factors that affect the formation of single person households and their housing decisions. Taiwan¡¦s population census data for 1980, 1990 and 2000 are used. Some interesting trends can be found. First of all, people who are married or cohabiting have exhibited an increasing tendency to live alone census by census. This shows the increasing need in a modern society for the husband and wife to live separately due to employment or other reasons. Secondly, unmarried and widowed elderly persons have had an increasing probability of living alone over the decades. Thirdly, the number of female single person households has been increasing rapidly, and there is a higher probability that they are homeowners and also occupying a larger living space than their male counterparts. To sum up, the results of this study show that the demand for housing among single person households will continue to increase as their numbers increase. Their demand for homeownership and living space are also increasing.Single person household formation; Tenure choice; Living space; Binary probit model; Sample selection model

Do Students in Montessori Schools Perform Better on Achievement Tests? A Taiwanese Perspective

The study examines whether elementary school students in Taiwan who had received Montessori education achieved significantly higher scores on tests of language arts, math, and social studies than students who attended non-Montessori elementary programs. One hundred ninety six children in first, second, and third grade participated in the study. Children’s scores were measured by Elementary School Language Ability Achievement Test (ESLAAT), Elementary School Math Ability Achievement Test (ESMAAT), and Social Studies Ability Achievement Test (SSAAT). One-way multivariate analysis of variance (MANOVA) showed that students who had Montessori experience had a significantly higher score in language arts in all three grade levels. In math, first grade students scored higher but not second and third grade students. However, in social studies, students who had received Montessori education did not score significantly higher than the non- Montessori students. There was also no significant difference between the number of years spent in Montessori programs and students’ language arts, math, and social studies test scores in first, second, and third grade

Mass profiles of clusters of galaxies : a comparison of X-ray and weak lensing observations

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2011.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (p. 149-163).Clusters of galaxies are useful probes of cosmology because they are the most massive bound systems and fair representatives of the matter composition of the universe. For clusters to be used as tracers of cosmic evolution, one must determine their masses with high accuracy. In this thesis, we provide a detailed comparison of mass estimates from X-rays and weak gravitational lensing for a sample of 32 intermediate low redshift clusters, and study the dependence of the mass profiles derived from these techniques on the dynamical state of the clusters. We analyze Chandra X-ray observations and compare the X-ray masses with published weak lensing data (Hoekstra, 2007; Okabe et al., 2010). The temperature, gas density, pressure, gas fraction profiles and their relation to the cluster morphology are also examined. We find that slopes of X-ray pressure and mass profiles vary with cluster morphology. Specifically, clusters with lower third-order power ratios P3=P0 (more relaxed) have the steepest profiles while high P3/P0 clusters (more disturbed) have the attest ones. The same trend is not obvious in weak lensing data. Consequently, a correlation between P3/P0 and the mass ratio of X-ray to weak lensing estimates MX/MWL, which in principle indicates the level of non-thermal pressure component in clusters, is found. For the entire sample, we find MX/MWL = 1.14±0.12 at R2500 (at 68% confidence). For apparently unrelaxed, high P3/P0 clusters, we find MX/MWL = 0.96 ± 0.12 at the same radius. For apparently relaxed, low P3/P0 clusters, we find MX/MWL = 1.32 ± 0.17, instead of MX/MWL = 1, expected if these clusters are in hydrostatic equilibrium. This may imply that the gas is hotter than the dark matter in cluster central regions (Rasia et al., 2004)..by En-Hsin Peng.Ph.D

Molecular characterization of the PhoPQ-PmrD-PmrAB mediated pathway regulating polymyxin B resistance in Klebsiella pneumoniae CG43

<p>Abstract</p> <p>Background</p> <p>The cationic peptide antibiotic polymyxin has recently been reevaluated in the treatment of severe infections caused by gram negative bacteria.</p> <p>Methods</p> <p>In this study, the genetic determinants for capsular polysaccharide level and lipopolysaccharide modification involved in polymyxin B resistance of the opportunistic pathogen <it>Klebsiella pneumoniae </it>were characterized. The expressional control of the genes responsible for the resistance was assessed by a LacZ reporter system. The PmrD connector-mediated regulation for the expression of <it>pmr </it>genes involved in polymyxin B resistance was also demonstrated by DNA EMSA, two-hybrid analysis and <it>in vitro </it>phosphor-transfer assay.</p> <p>Results</p> <p>Deletion of the <it>rcsB</it>, which encoded an activator for the production of capsular polysaccharide, had a minor effect on <it>K. pneumoniae </it>resistance to polymyxin B. On the other hand, deletion of <it>ugd </it>or <it>pmrF </it>gene resulted in a drastic reduction of the resistance. The polymyxin B resistance was shown to be regulated by the two-component response regulators PhoP and PmrA at low magnesium and high iron, respectively. Similar to the control identified in <it>Salmonella</it>, expression of <it>pmrD </it>in <it>K. pneumoniae </it>was dependent on PhoP, the activated PmrD would then bind to PmrA to prolong the phosphorylation state of the PmrA, and eventually turn on the expression of <it>pmr </it>for the resistance to polymyxin B.</p> <p>Conclusions</p> <p>The study reports a role of the capsular polysaccharide level and the <it>pmr </it>genes for <it>K. pneumoniae </it>resistance to polymyxin B. The PmrD connector-mediated pathway in governing the regulation of <it>pmr </it>expression was demonstrated. In comparison to the <it>pmr </it>regulation in <it>Salmonella</it>, PhoP in <it>K. pneumoniae </it>plays a major regulatory role in polymyxin B resistance.</p