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Dow Chemicalhttp://deepblue.lib.umich.edu/bitstream/2027.42/96203/1/me450f12project10_report.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/96203/2/me450f12project10_photo.jp

Comparative study of the impact of dietary supplementation with different types of CpG oligodeoxynucleotides (CpG ODNs) on enhancing intestinal microbiota diversity, antioxidant capacity, and immune-related gene expression profiles in Pacific white shrimp (Litopenaeus vannamei)

The CpG oligodeoxynucleotides (CpG ODNs) reportedly possess the capacity to strengthen immunity in mammals. This experiment was conducted to evaluate the impact of dietary supplementation with 17 types of CpG ODNs on intestinal microbiota diversity, antioxidant capacity, and immune-related gene expression profiles of the shrimp Litopenaeus vannamei. Diets including 50 mg kg-1 CpG ODNs wrapped in egg whites were prepared and divided into 17 different groups, with 2 control groups (normal feed and feed with egg whites). These CpG ODNs supplemented diets and the control diets were fed to L. vannamei (5.15 ± 0.54 g) three times daily at 5%-8% shrimp body weight for three weeks. The results of consecutive detection of intestinal microbiota by 16S rDNA sequencing indicated that 11 of the 17 types of CpG ODNs significantly enhanced intestinal microbiota diversity, increased the populations of several probiotic bacteria, and activated possible mechanisms relevant to diseases. The immune-related genes expression and antioxidant capacity in hepatopancreas further demonstrated that the 11 types of CpG ODNs effectively improved the innate immunity of shrimp. Additionally, histology results showed that the CpG ODNs in the experiment did not damage the tissue structure of hepatopancreas. The results suggest that CpG ODNs could be used as a trace supplement to improve the intestinal health and immunity of shrimp

Accurate Reconstruction of Molecular Phylogenies for Proteins Using Codon and Amino Acid Unified Sequence Alignments (CAUSA)

Based on molecular clock hypothesis, and neutral theory of molecular evolution, molecular phylogenies have been widely used for inferring evolutionary history of organisms and individual genes. Traditionally, alignments and phylogeny trees of proteins and their coding DNA sequences are constructed separately, thus often different conclusions were drawn. Here we present a new strategy for sequence alignment and phylogenetic tree reconstruction, codon and amino acid unified sequence alignment (CAUSA), which aligns DNA and protein sequences and draw phylogenetic trees in a unified manner. We demonstrated that CAUSA improves both the accuracy of multiple sequence alignments and phylogenetic trees by solving a variety of molecular evolutionary problems in virus, bacteria and mammals. Our results support the hypothesis that the molecular clock for proteins has two pointers existing separately in DNA and protein sequences. It is more accurate to read the molecular clock by combination (additive) of these two pointers, since the ticking rates of them are sometimes consistent, sometimes different. CAUSA software were released as Open Source under GNU/GPL license, and are downloadable free of charge from the website www.dnapluspro.com

Transcriptome and network analyses reveal key pathways and genes involved in response to carotenoid deposition in scallop muscle

Carotenoids are essential nutrients for humans and animals, and carotenoid content has become an important trait to evaluate the nutritional value of many cultured animals. Marine animals provide humans with diverse carotenoids, and developing carotenoid-enriched varieties has been the focus of marine animal breeding. Understanding the molecular mechanism of carotenoid deposition could benefit marine animal breeding for carotenoid content improvement. In the present study, transcriptomic analysis of adductor muscle was performed between Yesso scallop (Patinopecten yessoensis) with white muscle (WM) and carotenoid-enriched orange muscle (OM). A total of 683 differentially expressed genes (DEGs) were identified, with 302 and 381 genes being up- and down-regulated in OM scallop. Gene co-expression network analysis identified four carotenoid accumulation−related modules, including three up-regulated modules and one down-regulated module. The genes in up-regulated modules mainly participate in the pathways of translation and transcription (MEgreen), immune system (MElightyellow), and lipid metabolism (MEpink), while the down-regulated module is mainly enriched with genes involved in various metabolic pathways (MEturquoise). As the causal gene responsible for muscle coloration in scallop, PyBCO-like 1 is the hub gene of MEturquoise and showed strong connectivity with NR2F1A, a transcriptional factor involved in the regulation of retinoic acid. In addition, the up-regulated DEGs, including WDR3, RPP29, TBL3, RIOK2, and NOB1 from “ribosome biogenesis”, HSP70s and HSP702Bs from “antigen processing and presentation”, and ACOX1 from “PPAR signaling pathway” were identified as hub genes, indicating the potential regulatory role of these genes and pathways in response to carotenoid accumulation. Our data contribute to a deeper understanding of the regulatory and response mechanisms of carotenoid accumulation in marine animals

Associations of COVID-19 lockdown with birth weight in China

BackgroundDuring the special period of the global spread of COVID-19, pregnant women are sensitive groups to the impacts of COVID-19 epidemic. However, the effects of lockdown measures implemented in response to the COVID-19 on fetal birthweight remain unclear.ObjectivesThis study investigated the associations of COVID-19 lockdown with birth weight in Chinese population.MethodsWe collected 730,153 data of participants from hospitals of five cities in the south of China, we defined the time period of level I response (1/23-2/24/2020) as level I lockdown, and women who were pregnant during level I lockdown as the exposure group. Women who were pregnant during the same calendar month from 2015 to 2019 were defined as the unexposed group. We quantitatively estimate the individual cumulative exposure dose by giving different weights to days with different emergency response levels. Generalized linear regression models were used to estimate the association between COVID-19 lockdown exposure with birth weight and risk of low birth weight (<2,500 g) and macrosomia (>4,000 g).ResultsThe birth weight of the exposed group is heavier than the unexposed group (3,238.52 vs. 3,224.11 g: adjusted β = 24.39 g [95% CI: 21.88, 26.91 g]). The exposed group had a higher risk of macrosomia (2.8% vs. 2.6%; adjusted OR = 1.17 [95% CI: 1.12, 1.22]). More obvious associations were found between COVID-19 lockdown and macrosomia in women who experienced the lockdown in their early pregnancy. Women who experienced the lockdown at their 4–7 weeks of pregnancy showed statistically significant heavier birth weight than unexposed group (after adjustment): β = 1.28 (95% CI: 1.11, 1.46) g. We also observed a positive association between cumulative exposure dose of COVID-19 lockdown in all pregnant women and birth weight, after divided into four groups, Q1: β = 32.95 (95% CI: 28.16, 37.75) g; Q2: β = 18.88 (95% CI: 14.12, 23.64) g; Q3: β = 19.50 (95% CI: 14.73, 24.28) g; Q4: β = 21.82 (95% CI: 17.08, 26.56) g. However, there was no statistically significant difference in the risk of low birth weight between exposed and unexposed groups.ConclusionsThe COVID-19 lockdown measures were associated with a heavier birth weight and a higher risk of macrosomia. Early pregnancy periods may be a more susceptible exposure window for a heavier birth weight and a higher risk of macrosomia. We also observed a positive association between cumulative exposure dose of COVID-19 lockdown and birth weight. The government and health institutions should pay attention to the long-term health of the infants born during the COVID-19 lockdown period, and follow up these mothers and infants is necessary

On drift parameter estimation for mean-reversion type stochastic differential equations with discrete observations

We study the parameter estimation for mean-reversion type stochastic differential equations driven by Brownian motion. The equations, involving a small dispersion parameter, are observed at discrete (regularly spaced) time instants. The least square method is utilized to derive an asymptotically consistent estimator. Discussions on the rate of convergence of the least square estimator are presented. The new feature of this study is that, due to the mean-reversion type drift coefficient in the stochastic differential equations, we have to use the Girsanov transformation to simplify the equations, which then gives rise to the corresponding convergence of the least square estimator being with respect to a family of probability measures indexed by the dispersion parameter, while in the literature the existing results have dealt with convergence with respect to a given probability measure

Transcriptome Sequencing and Characterization for the Sea Cucumber Apostichopus japonicus (Selenka, 1867)

Background: Sea cucumbers are a special group of marine invertebrates. They occupy a taxonomic position that is believed to be important for understanding the origin and evolution of deuterostomes. Some of them such as Apostichopus japonicus represent commercially important aquaculture species in Asian countries. Many efforts have been devoted to increasing the number of expressed sequence tags (ESTs) for A. japonicus, but a comprehensive characterization of its transcriptome remains lacking. Here, we performed the large-scale transcriptome profiling and characterization by pyrosequencing diverse cDNA libraries from A. japonicus. Results: In total, 1,061,078 reads were obtained by 454 sequencing of eight cDNA libraries representing different developmental stages and adult tissues in A. japonicus. These reads were assembled into 29,666 isotigs, which were further clustered into 21,071 isogroups. Nearly 40 % of the isogroups showed significant matches to known proteins based on sequence similarity. Gene ontology (GO) and KEGG pathway analyses recovered diverse biological functions and processes. Candidate genes that were potentially involved in aestivation were identified. Transcriptome comparison with the sea urchin Strongylocentrotus purpuratus revealed similar patterns of GO term representation. In addition, 4,882 putative orthologous genes were identified, of which 202 were not present in the non-echinoderm organisms. More than 700 simple sequence repeats (SSRs) and 54,000 single nucleotide polymorphisms (SNPs) were detected in the A. japonicu

BREAST CANCER DETECTION: FROM TUMOR-SPECIFIC NANOPARTICLES TO CELL MECHANICS

This thesis presents combined experimental and theoretical studies of cancer cell mechanics and peptide-enhanced nanoparticle entry/adhesion to triple negative breast cancer (TNBC) cells. The adhesive interaction between functionalized nanoparticles and biological cells is critical for effective cancer targeting. A combination of atomic force microscopy (AFM) and simulation approaches are used to evaluate the adhesion and molecular origin of adhesive interactions, respectively, between Triptorelin (a Luteinizing Hormone-Releasing Hormone (LHRH) agonist)-conjugated poly-(ethylene glycol) (PEG)-coated magnetite nanoparticles (Triptorelin-MNPs) and breast cells. AFM results show that Triptorelin-MNPs have a fourteen-fold greater work of adhesion to TNBC cells than to normal breast cells. Hence, the experimental observation indicates that specific receptor-ligand adhesion facilitates Triptorelin-MNPs to target TNBC cells. In addition, the simulations reveal that the adhesive interactions are dominated by van der Waals forces and electrostatic interactions. Both experimental and computational studies suggest that PEG serves as an effective coating that enhances adhesive interactions to breast cancer cells. These results highlight the potential to develop Triptorelin-MNPs into tumor-specific MRI contrast agents and drug carriers. To investigate Triptorelin-MNP cluster entry mechanism and cellular uptake efficacy, thermodynamics and kinetics modeling and optical/confocal fluorescence microscopy are used to show that Triptorelin ligands enhance the uptake of Triptorelin-MNPs into TNBC cells. The trends in the predicted cluster entry times (into TNBC cells) and the size ranges of the engulfed nanoparticle clusters (within the TNBC cells) are shown to be consistent with experimental observations. Finally, a cell mechanics approach is explored for TNBC cell detection. This involves the use of a shear assay technique, in parallel with digital image correlation and a Maxwell model for the measurements of viscoelastic properties as effective biomarkers. The reduced cell viscoelastic properties (e.g. moduli and viscosities) of TNBC cells are associated with the reduction of actin filament structural components, and the loss of actin organization. These results suggest that the shear assay technique may serve as an effective screening tool for TNBC cell detection