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101.
Respiratory syncytial virus (RSV) infection results in millions of hospitalizations and thousands of deaths each year. Variations in the adaptive and innate immune response appear to be associated with RSV severity. To investigate the host response to RSV infection in infants, we performed a systems-level study of RSV pathophysiology, incorporating high-throughput measurements of the peripheral innate and adaptive immune systems and the airway epithelium and microbiota. We implemented a novel multi-omic data integration method based on multilayered principal component analysis, penalized regression, and feature weight back-propagation, which enabled us to identify cellular pathways associated with RSV severity. In both airway and immune cells, we found an association between RSV severity and activation of pathways controlling Th17 and acute phase response signaling, as well as inhibition of B cell receptor signaling. Dysregulation of both the humoral and mucosal response to RSV may play a critical role in determining illness severity.  相似文献   
102.
Coral Reefs - Storms strongly affect coral reefs; one unstudied but potentially important outcome may be a decrease in herbivory, presumably through changes to freshwater, sediment and nutrient...  相似文献   
103.
104.
Pelagic egg development in red drum, Sciaenops ocellatus, is described using tiered staging. Based on mitosis and meiosis, there are five periods: Mitosis of Oogonia, Active Meiosis I, Arrested Meiosis I, Active Meiosis II, and Arrested Meiosis II. The Periods are divided into six stages: Mitotic Division of Oogonia, Chromatin Nucleolus, Primary Growth, Secondary Growth, Oocyte Maturation and Ovulation. The Chromatin Nucleolus Stage is divided into four steps: Leptotene, Zygotene, Pachytene, and Early Diplotene. Oocytes in the last step possess one nucleolus, dispersed chromatin with forming lampbrush chromosomes and lack basophilic ooplasm. The Primary Growth Stage, characterized by basophilic ooplasm and absence of yolk in oocytes, is divided into five steps: One‐Nucleolus, Multiple Nucleoli, Perinucleolar, Oil Droplets, and Cortical Alveolar. During primary growth, the Balbiani body develops from nuage, enlarges and disperses throughout the ooplasm as both endoplasmic reticulum and Golgi develop within it. Secondary growth or vitellogenesis has three steps: Early Secondary Growth, Late Secondary Growth and Full‐Grown. The Oocyte Maturation Stage, including ooplasmic and germinal vesicle maturation, has four steps: Eccentric Germinal Vesicle, Germinal Vesicle Migration, Germinal Vesicle Breakdown and Resumption of Meiosis when complete yolk hydration occurs. The period is Arrested Meiosis II. When folliculogenesis is completed, the ovarian follicle, an oocyte and encompassing follicle cells, is surrounded by a basement membrane and developing theca, all forming a follicle complex. After ovulation, a newly defined postovulatory follicle complex remains attached to the germinal epithelium. It is composed of a basement membrane that separates the postovulatory follicle from the postovulatory theca. Arrested Meiosis I encompasses primary and secondary growth (vitellogenesis) and includes most of oocyte maturation until the resumption of meiosis (Active Meiosis II). The last stage, Ovulation, is the emergence of the oocyte from the follicle when it becomes an egg or ovum. J. Morphol. 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
105.
Variance component (VC) approaches based on restricted maximum likelihood (REML) have been used as an attractive method for positioning of quantitative trait loci (QTL). Linkage disequilibrium (LD) information can be easily implemented in the covariance structure among QTL effects (e.g. genotype relationship matrix) and mapping resolution appears to be high. Because of the use of LD information, the covariance structure becomes much richer and denser compared to the use of linkage information alone. This makes an average information (AI) REML algorithm based on mixed model equations and sparse matrix techniques less useful. In addition, (near-) singularity problems often occur with high marker densities, which is common in fine-mapping, causing numerical problems in AIREML based on mixed model equations. The present study investigates the direct use of the variance covariance matrix of all observations in AIREML for LD mapping with a general complex pedigree. The method presented is more efficient than the usual approach based on mixed model equations and robust to numerical problems caused by near-singularity due to closely linked markers. It is also feasible to fit multiple QTL simultaneously in the proposed method whereas this would drastically increase computing time when using mixed model equation-based methods.  相似文献   
106.
Modification of a 2-iminobenzimidazole series derived from an HTS hit resulted in compounds with improved in-vitro species selectivity. Incorporation of an 8-quinoline amide and conformational rigidification of an aliphatic tether furnished potent compounds suitable for further lead optimization.  相似文献   
107.
CressExpress is a user-friendly, online, coexpression analysis tool for Arabidopsis (Arabidopsis thaliana) microarray expression data that computes patterns of correlated expression between user-entered query genes and the rest of the genes in the genome. Unlike other coexpression tools, CressExpress allows characterization of tissue-specific coexpression networks through user-driven filtering of input data based on sample tissue type. CressExpress also performs pathway-level coexpression analysis on each set of query genes, identifying and ranking genes based on their common connections with two or more query genes. This allows identification of novel candidates for involvement in common processes and functions represented by the query group. Users launch experiments using an easy-to-use Web-based interface and then receive the full complement of results, along with a record of tool settings and parameters, via an e-mail link to the CressExpress Web site. Data sets featured in CressExpress are strictly versioned and include expression data from MAS5, GCRMA, and RMA array processing algorithms. To demonstrate applications for CressExpress, we present coexpression analyses of cellulose synthase genes, indolic glucosinolate biosynthesis, and flowering. We show that subselecting sample types produces a richer network for genes involved in flowering in Arabidopsis. CressExpress provides direct access to expression values via an easy-to-use URL-based Web service, allowing users to determine quickly if their query genes are coexpressed with each other and likely to yield informative pathway-level coexpression results. The tool is available at http://www.cressexpress.org.  相似文献   
108.
In a simulation study, different designs were compared for efficiency of fine-mapping of QTL. The variance component method for fine-mapping of QTL was used to estimate QTL position and variance components. The design of many families with small size gave a higher mapping resolution than a design with few families of large size. However, the difference is small in half sib designs. The proportion of replicates with the QTL positioned within 3 cM of the true position is 0.71 in the best design, and 0.68 in the worst design applied to 128 animals with a phenotypic record and a QTL explaining 25% of the phenotypic variance. The design of two half sib families each of size 64 was further investigated for a hypothetical population with effective size of 1000 simulated for 6000 generations with a marker density of 0.25 cM and with marker mutation rate 4 × 10-4 per generation. In mapping using bi-allelic markers, 42~55% of replicated simulations could position QTL within 0.75 cM of the true position whereas this was higher for multi allelic markers (48~76%). The accuracy was lowest (48%) when mutation age was 100 generations and increased to 68% and 76% for mutation ages of 200 and 500 generations, respectively, after which it was about 70% for mutation ages of 1000 generations and older. When effective size was linearly decreasing in the last 50 generations, the accuracy was decreased (56 to 70%). We show that half sib designs that have often been used for linkage mapping can have sufficient information for fine-mapping of QTL. It is suggested that the same design with the same animals for linkage mapping should be used for fine-mapping so gene mapping can be cost effective in livestock populations.  相似文献   
109.
Summary Quantitative morphometric studies with the electron microscope were made on the prolactin cells of wild freshwater sailfin mollies taken in Florida in August at four different times of day. The results indicate a circadian rhythm in the prolactin cell, the period of highest synthetic activity being from midday to evening, as indicated by the condition of nucleus, Golgi apparatus and rough endoplasmic reticulum, and by the incidence of granule release profiles. No circadian changes were detected in the ACTH cells.Several distinct sites of prolactin granule release were recognised. However, there was no conclusive evidence of granule release by any mechanism other than classical exocytosis.We thank Mr. W. Thomson for technical assistance and Ann Grier for help in collecting the fish. T.F.C. Batten is in receipt of an S.R.C. Research Studentship.  相似文献   
110.

Introduction

We describe initial validation of a new system for digital to analog conversion (DAC) and reconstruction of 12-lead ECGs. The system utilizes an open and optimized software format with a commensurately optimized DAC hardware configuration to accurately reproduce, from digital files, the original analog electrocardiographic signals of previously instrumented patients. By doing so, the system also ultimately allows for transmission of data collected on one manufacturer''s 12-lead ECG hardware/software into that of any other.

Materials and Methods

To initially validate the system, we compared original and post-DAC re-digitized 12-lead ECG data files (∼5-minutes long) in two types of validation studies in 10 patients. The first type quantitatively compared the total waveform voltage differences between the original and re-digitized data while the second type qualitatively compared the automated electrocardiographic diagnostic statements generated by the original versus re-digitized data.

Results

The grand-averaged difference in root mean squared voltage between the original and re-digitized data was 20.8 µV per channel when re-digitization involved the same manufacturer''s analog to digital converter (ADC) as the original digitization, and 28.4 µV per channel when it involved a different manufacturer''s ADC. Automated diagnostic statements generated by the original versus reconstructed data did not differ when using the diagnostic algorithm from the same manufacturer on whose device the original data were collected, and differed only slightly for just 1 of 10 patients when using a third-party diagnostic algorithm throughout.

Conclusion

Original analog 12-lead ECG signals can be reconstructed from digital data files with accuracy sufficient for clinical use. Such reconstructions can readily enable automated second opinions for difficult-to-interpret 12-lead ECGs, either locally or remotely through the use of dedicated or cloud-based servers.  相似文献   
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