2,938 research outputs found
Transcriptional Regulation of the Drosophila Peptidoglycan Sensor PGRP-LC by the Steroid Hormone Ecdysone: A Masters Thesis
Drosophila is host to the steroid hormone ecdysone, which regulates development and immune functions using a common group of transcription factors. Developmentally-induced ecdysone pulses activate the expression of the EcR, BR-C, HR46, Eip74EF, Eip75B, Eip78C, and Eip93F, which assume control of hundreds of other genes involved in the transition from larva to pupa stage. Many of the transcription factors are related to mammalian nuclear hormone receptors by homology. In addition to these transcription factors, the ecdysoneregulated GATA factors SRP and PNR are required for the proper expression of the peptidoglycan sensor PGRP-LC, which belongs to a conserved class of proteins in innate immunity. Although the transcriptional network has been elucidated in development, it is unclear why ecdysone control of PGRP-LC gene activity involves these nine transcription factors and how ecdysone is regulated in the context of an infection in vivo.
An ecdysone-activated enhancer was located upstream of the PGRP-LC locus using a reporter plasmid. Female flies that lacked the enhancer had reduced PGRP-LC expression, but survived infection. Male flies did not experience these changes. Therefore, PGRP-LC enhancer appears to be a female-specific cis-regulatory element. The lack of survival phenotype could be caused by using an improper injection site. Bioinformatics software was used to identify putative individual and overlapping binding sites for some transcription factors. Site-directed mutations of the motifs reduced PGRP-LC promoter activity without abolishing the signal. These results suggest that the transcription factors assemble at multiple locations on the PGRP-LC enhancer and form strong protein-protein bonds. Septic injury led to elevated ecdysone in whole flies, which could be a neuroendocrine response to stress similar to the mammalian system. Steroid hormone regulation of immune receptors is a common theme in humans and flies, and these results could advance our understanding of the transcriptional regulation of related genes and gender differences observed in innate immune responses at the transcriptional level
The largest virialized dark halo in the universe
Using semi-analytic approach, we present an estimate of the properties of the
largest virialized dark halos in the present universe for three different
scenarios of structure formation: SCDM, LCDM and OCDM models. The resulting
virial mass and temperature increase from the lowest values of and 9.8 keV in OCDM, the mid-range values of and 31 keV in LCDM, to the highest values of
, 65 keV in SCDM. As compared with the
largest virialized object seen in the universe, the richest clusters of
galaxies, we can safely rule out the OCDM model. In addition, the SCDM model is
very unlikely because of the unreasonably high virial mass and temperature. Our
computation favors the prevailing LCDM model in which superclusters may be
marginally regarded as dynamically-virialized systems.Comment: 5 pages, Accepted by Int. J. Mod. Phys.
Is prenatal maternal mental problem associated with offspring's language skills at two years old?
The current study examined the impact of prenatal maternal anxiety on toddlersâ language development at two years old. Maternal anxiety status of 48, 36 and 32 pregnant women was evaluated using a validated questionnaire during pregnancy at the first, second and third trimesters respectively. Mothers were grouped into anxious and non-anxious groups according to the clinical cut-off. Two year postpartum anxiety level of all the mothers was obtained as a covariate. Childrenâs language abilities were assessed using the Cantonese version of the MacArthur Communicative Development Inventory (CCDI). Results showed that there was no significant difference between the language scores reported in the prenatally âanxiousâ and ânon-anxiousâ groups in all three trimesters after controlling for the 2-year postpartum anxiety level. The results implied that effect of prenatal maternal stress is not associated with childrenâs language functioning. Language acquisition is a complex process influenced by multiple factors. This study highlighted some methodological considerations when conducting similar kind of study.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science
Deep Person Generation: A Survey from the Perspective of Face, Pose and Cloth Synthesis
Deep person generation has attracted extensive research attention due to its
wide applications in virtual agents, video conferencing, online shopping and
art/movie production. With the advancement of deep learning, visual appearances
(face, pose, cloth) of a person image can be easily generated or manipulated on
demand. In this survey, we first summarize the scope of person generation, and
then systematically review recent progress and technical trends in deep person
generation, covering three major tasks: talking-head generation (face),
pose-guided person generation (pose) and garment-oriented person generation
(cloth). More than two hundred papers are covered for a thorough overview, and
the milestone works are highlighted to witness the major technical
breakthrough. Based on these fundamental tasks, a number of applications are
investigated, e.g., virtual fitting, digital human, generative data
augmentation. We hope this survey could shed some light on the future prospects
of deep person generation, and provide a helpful foundation for full
applications towards digital human
No Weight Catch-Up Growth of SGA Infants Is Associated with Impaired Insulin Sensitivity during the Early Postnatal Period
Objective. To investigate the relationship between weight catch-up growth and insulin sensitivity in small for gestational age (SGA) infants. Methods. Forty-four singleton SGA subjects met the inclusion criteria and finished-3-month followup. Body weight, length, fasting glucose, and fasting insulin (FI) levels were measured at 3 days and 3 months. Insulin sensitivity was evaluated by FI and homeostasis model assessment (HOMA). Results. According to the change of weight Z-score, forty-four subjects were divided into two groups: noncatch-up growth (NCUG) and catch-up growth (CUG). By 3 months of age, the body weight, body length and BMI of NCUG group were significantly lower than those of CUG group. The FI and HOMA were significantly higher in NCUG group. The change of weight Z-score during 3 months was inversely related to the HOMA at 3 months. Conclusion. Our data exemplified that no weight catch-up growth during the first 3 months was associated with impaired insulin sensitivity in SGA infants
The development and confirmatory factor analysis of the Service-Learning Reflection Scale for undergraduates
The purpose of this study is to develop and to examine the construct validity of the service-learning reflection scale for undergraduates based on Kolb\u27s learning theory. The research aims to: (1) recognize undergraduates\u27 levels of reflection for service-learning; (2) let undergraduates understand their learning styles; (3) evaluate the effect of service-learning for the instructors. We used the Likert\u27s style to make the scales. There are 33 items in the initial scale divided into four subscales inclusive of the concrete experience (CE), the reflection observation (RO), the abstract conceptualization (AC), and the active experience (AE). For the very first time, we invite four experts to evaluate all the items to proceed three times Delphi technique process. We adopt the item analysis, exploratory factor analysis and reliability analysis via 326 participants in the pretest. Cronbach\u27s alpha reliability coefficients of the four subscales are from .80 to .87, and that of the total scale was .95. The whole explained variance was 60.16%.
In this study, we make use of the stratified sampling, 1,251 undergraduates, to analyze the construct validity by the confirmatory factor analysis. The model index such as GFI, AGFI, NFI, RFI, IFI and CFI are above .90, RMSEA and RMR are below .05, as well as PGFI and PNFI are above .50. In addition, the structural equation modeling analysis indicates measurement weights, measurement intercepts, structural covariance matrixes and measurement residuals of male/female and general/technical undergraduates groups are no significant differences. Moreover, the Cronbach\u27s alpha values of the four subscales are from .85 to .86, and that of the total scale is .95. The results show that the CFA and reliability analysis confirm the theoretical structure as well
Autophagy and oxidative stress in cardiovascular diseases
AbstractAutophagy is a highly conserved degradation process by which intracellular components, including soluble macromolecules (e.g. nucleic acids, proteins, carbohydrates, and lipids) and dysfunctional organelles (e.g. mitochondria, ribosomes, peroxisomes, and endoplasmic reticulum) are degraded by the lysosome. Autophagy is orchestrated by the autophagy related protein (Atg) composed protein complexes to form autophagosomes, which fuse with lysosomes to generate autolysosomes where the contents are degraded to provide energy for cell survival in response to environmental and cellular stress. Autophagy is an important player in cardiovascular disease development such as atherosclerosis, cardiac ischemia/reperfusion, cardiomyopathy, heart failure and hypertension. Autophagy in particular contributes to cardiac ischemia, hypertension and diabetes by interaction with reactive oxygen species generated in endoplasmic reticulum and mitochondria. This review highlights the dual role of autophagy in cardiovascular disease development. Full recognition of autophagy as an adaptive or maladaptive response would provide potential new strategies for cardiovascular disease prevention and management. This article is part of a Special Issue entitled: Autophagy and protein quality control in cardiometabolic diseases
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