Part I: Rapid Synthesis of Dendrimers by an Orthogonal Coupling Strategy. Part II: Design, Synthesis, and Characterization of Hydrogen-Bond Mediated Self-Assembling Dendrimers

220 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1997.Part II. Discrete aggregates with a size in the nano-scale were formed by the hydrogen-bond mediated self-assembly of dendritic macromolecules. Several hydrogen bonding units were investigated, including anthyridine and diaminodihydropyridine moieties that are complementary (AAA-DDD), and self-complementary isophthalic acid, and 6-aminonicotinic acid subunits. Among them, dendritic tetraacids 189a-d were shown to self-assemble in a generation-dependent manner. The lower generation tetraacid 189a prefers to form a series of linear aggregates, while the higher generation tetraacids 189b-d tend to form a cyclic hexamer. The observation was supported by SEC dilution studies, VPO, and comparison with covalent models 208a-c.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Impacts of sow behaviour on reproductive performance: current understanding

ABSTRACTFrom the perspective of animal welfare, sows housed in group housing systems are recommended, which is conducive to health problems and the release of natural behaviour, but can lead to other problems such as social pressure due to competition for limited resources. Sow natural behaviour can be used to improve physiological and mental health to ameliorate reproductive performance. However, the natural behaviour of sow is ignored in modern intensive housing groups. The challenges faced by social behaviour, maternal behaviour and dietary behaviour of sows in a group-housing system are discussed in this paper. Furthermore, many management strategies will affect sow behaviour, such as diet management and housing systems, providing adequate nutrition, and a reasonable environment for sows. These can be considered the basis for the successful farrowing of high-production sows. Therefore, sow performance can be improved by influencing sow behaviour through management strategies such as reasonable stocking density, a good feeding environment and suitable feed for the growth stage

Development of a Conventional RT-PCR Assay for Rapid Detection of Porcine Deltacoronavirus with the Same Detection Limit as a SYBR Green-Based Real-Time RT-PCR Assay

Porcine deltacoronavirus (PDCoV) is a newly discovered coronavirus, which belongs to the family Coronaviridae. It causes watery diarrhea, vomiting, and dehydration in newborn piglets. A sensitive RT-PCR method is urgently required to detect PDCoV infection. In this study, we developed and evaluated a conventional RT-PCR assay and a SYBR green-based real-time RT-PCR assay that targeted the PDCoV n gene. Both assays are specific and have the same limit of detection at 2 × 101 copies of RNA molecules per reaction. Eighty-four clinical samples were subjected to both conventional RT-PCR and real-time RT-PCR, and the same positive rate (41.7%) was achieved, which was much higher than the positive rate (26.2%) using a previously described one-step RT-PCR technique. In summary, a conventional RT-PCR technique was successfully established for the detection of PDCoV with the same detection limit as a SYBR green-based real-time RT-PCR assay

Involvement of Porcine β-Defensin 129 in Sperm Capacitation and Rescue of Poor Sperm in Genital Tract Infection

In mammals, β-defensins have been reported to play pivotal roles in sperm protection and fertilization. However, the function and mechanism of porcine β-defensin 129 (pBD129) in the sperm remain unclear. Here, we demonstrate that pBD129 is a glycosylated protein and broadly exists in accessory sex glands and coats the sperm surface. We inhibited the pBD129 protein on the sperm surface with an anti-pBD129 antibody and found that sperm motility was not significantly affected; however, sperm acrosome integrity and tyrosine phosphorylation levels increased significantly with time (p < 0.05) during capacitation. These changes were accompanied by an increase in sperm Ca2+ influx, resulting in a significantly reduced in vitro fertilization cleavage rate (p < 0.05). Further investigation revealed that treatment with recombinant pBD129 markedly restored the sperm motility in semen contaminated with Escherichia coli. The results suggest that pBD129 is not only associated with poor sperm motility after genital tract infection but can also protect the spermatozoa from premature capacitation, which may be beneficial for semen preservation

Development and evaluation of a broadly reactive reverse transcription recombinase polymerase amplification assay for rapid detection of murine norovirus

Abstract Background Murine norovirus (MNV) is recognized as the most prevalent viral pathogen in captive mouse colonies. The rapid detection assay for MNV would be a useful tool for monitoring and preventing MNV infection. A recombinase polymerase amplification (RPA) assay was established in this study to provide a solution for rapid and sensitive detection of MNV. Results The detection limit of the RT-RPA assay for the detection of MNV was 1 × 102 copies of RNA molecules per reaction. The assay was specific since there was no cross-reaction with other common murine viruses. In addition, the broad reactivity of the RT-RPA assay was validated using the synthesized template carrying seven point mutations among several MNV strains. The MNV RT-RPA assay could detect as few as 1 × 102 copies of the mutant per reaction, suggesting the assay could be broadly reactive against a large diversity of MNV strains. Forty eight clinical samples including 16 gastric tissue specimens, 16 cecal tissue specimens and 16 fecal specimens were tested for the validation of the new developed RT-RPA assay. The detection results of RT-RPA and RT-qPCR for clinical samples were very similar, except that a gastric tissue sample which was positive by RT-qPCR, with a RNA titer of 27 copies, was negative by RT-RPA. Conclusions A broadly reactive RT-RPA assay was successfully established for MNV detection