<Emphasis Type="Italic">In vitro</Emphasis> bioassay as a predictor of <Emphasis Type="Italic">in vivo</Emphasis> response

Background  

There is a substantial discrepancy between in vitro and in vivo experiments. The purpose of the present work was development of a theoretical framework to enable improved prediction of in vivo response from in vitro bioassay results.     

<Emphasis Type="Italic">In vivo</Emphasis> molecular imaging of experimental joint inflammation by combined <Superscript>18</Superscript>F-FDG positron emission tomography and computed tomography

Introduction  

The purpose of this work was to establish and validate combined small animal positron emission tomography - computed tomography (PET/CT) as a new in vivo imaging method for visualisation and quantification of joint inflammation.     

In vivo observation of gold nanoparticles in the central nervous system of <Emphasis Type="Italic">Blaberus discoidalis</Emphasis>

Background  

Nanoparticles (NPs) are widely studied for biomedical applications. Understanding interactions between NPs and biomolecules or cells has yet to be achieved. Here we present a novel in vivo method to study interactions between NPs and the nervous system of the discoid or false dead-head roach, Blaberus discoidalis. The aims of this study were to present a new and effective method to observe NPs in vivo that opens the door to new methods of study to observe the interactions between NPs and biological systems and to present an inexpensive and easy-to-handle biological system.     

Fine-scale genetic mapping of a hybrid sterility factor between <Emphasis Type="Italic">Drosophila simulans</Emphasis> and <Emphasis Type="Italic">D. mauritiana</Emphasis>: the varied and elusive functions of "speciation genes"

Background  

Hybrid male sterility (HMS) is a usual outcome of hybridization between closely related animal species. It arises because interactions between alleles that are functional within one species may be disrupted in hybrids. The identification of genes leading to hybrid sterility is of great interest for understanding the evolutionary process of speciation. In the current work we used marked P-element insertions as dominant markers to efficiently locate one genetic factor causing a severe reduction in fertility in hybrid males of Drosophila simulans and D. mauritiana.     

An effective approach for identification of <Emphasis Type="Italic">in vivo</Emphasis> protein-DNA binding sites from paired-end ChIP-Seq data

Background  

ChIP-Seq, which combines chromatin immunoprecipitation (ChIP) with high-throughput massively parallel sequencing, is increasingly being used for identification of protein-DNA interactions in vivo in the genome. However, to maximize the effectiveness of data analysis of such sequences requires the development of new algorithms that are able to accurately predict DNA-protein binding sites.     

<Emphasis Type="Italic">In vitro</Emphasis> gene regulatory networks predict <Emphasis Type="Italic">in vivo</Emphasis> function of liver

Background  

Evolution of toxicity testing is predicated upon using in vitro cell based systems to rapidly screen and predict how a chemical might cause toxicity to an organ in vivo. However, the degree to which we can extend in vitro results to in vivo activity and possible mechanisms of action remains to be fully addressed.     

Production of glycoprotein vaccines in <Emphasis Type="Italic">Escherichia coli</Emphasis>

Background  

Conjugate vaccines in which polysaccharide antigens are covalently linked to carrier proteins belong to the most effective and safest vaccines against bacterial pathogens. State-of-the art production of conjugate vaccines using chemical methods is a laborious, multi-step process. In vivo enzymatic coupling using the general glycosylation pathway of Campylobacter jejuni in recombinant Escherichia coli has been suggested as a simpler method for producing conjugate vaccines. In this study we describe the in vivo biosynthesis of two novel conjugate vaccine candidates against Shigella dysenteriae type 1, an important bacterial pathogen causing severe gastro-intestinal disease states mainly in developing countries.     

Wavelet to predict bacterial <Emphasis Type="Italic">ori</Emphasis> and <Emphasis Type="Italic">ter</Emphasis>: a tendency towards a physical balance

Background  

Chromosomal DNA replication in bacteria starts at the origin (ori) and the two replicores propagate in opposite directions up to the terminus (ter) region. We hypothesize that the two replicores need to reach ter at the same time to maintain a physical balance; DNA insertion would disrupt such a balance, requiring chromosomal rearrangements to restore the balance. To test this hypothesis, we needed to demonstrate that ori and ter are in a physical balance in bacterial chromosomes. Using wavelet analysis, we documented GC skew, AT skew, purine excess and keto excess on the published bacterial genomic sequences to locate the turning (minimum and maximum) points on the curves. Previously, the minimum point had been supposed to correlate with ori and the maximum to correlate with ter.     

Manufacture of IRDye800CW-coupled Fe<Subscript>3</Subscript>O<Subscript>4</Subscript> nanoparticles and their applications in cell labeling and <Emphasis Type="Italic">in vivo</Emphasis> imaging

Background  

In recent years, near-infrared fluorescence (NIRF)-labeled iron nanoparticles have been synthesized and applied in a number of applications, including the labeling of human cells for monitoring the engraftment process, imaging tumors, sensoring the in vivo molecular environment surrounding nanoparticles and tracing their in vivo biodistribution. These studies demonstrate that NIRF-labeled iron nanoparticles provide an efficient probe for cell labeling. Furthermore, the in vivo imaging studies show excellent performance of the NIR fluorophores. However, there is a limited selection of NIRF-labeled iron nanoparticles with an optimal wavelength for imaging around 800 nm, where tissue autofluorescence is minimal. Therefore, it is necessary to develop additional alternative NIRF-labeled iron nanoparticles for application in this area.     

Effect of white light on meristematic activity in developing sunflower hypocotyls

Summary To determine whether hypocotyl elongation in sunflower seedlings (Helianthus annuus L.) is dependent on cell divisions (meristematic activity), we used a specific inhibitor of DNA synthesis (fluorodeoxyuridine). The seedlings were either grown for 6 days in darkness or continuous white light (WL). Under both conditions hypocotyl growth was retarded by 30–70% in the presence of the inhibitor. Because the nuclei do not become endopolyploid we conclude that hypocotyl growth is dependent on cell reproduction. In the next step an immunocytochemical method was used to detect the percentage of nuclei in S-phase (meristematic activity) in different regions and tissues of the hypocotyls. In the peripheral cell layers (epidermis, cortex) meristematic activity was much greater than in the pith of the organ. In rapidly growing (etiolated) hypocotyls meristematic activity is largely restricted to the closed apical hook of the stem. After transfer to WL the hook opens and hypocotyl elongation is inhibited. In the epidermis and cortex of the apical hook a large WL-induced enhancement in the percentage of nuclei in S-phase occurred, which was followed by a light-mediated retardation of meristematic activity. Our data show that WL exerts a transient stimulatory effect on meristematic activity during photomorphogenesis of the sunflower seedling.Abbreviations BrdUrd 5-bromo-2-deoxyuridine - D darkness - FdUrd 5-fluoro-2-deoxyuridine - TRITC tetramethyl-rhodamine-isothiocyanate - WL white light     

A previously unidentified <Emphasis Type="Italic">Chorioptes</Emphasis> species infesting outer ear canals of moose (<Emphasis Type="Italic">Alces alces</Emphasis>): characterization of the mite and the pathology of infestation

Background  

During the past decade, Chorioptes mites occupying the outer ear canals have been a common finding at routine necropsies of moose (Alces alces) in Sweden, but neither the taxonomy of the mites nor lesions from the infestation have been investigated. In this study, the mites are characterized by morphological and molecular techniques, and the histopathology of the skin of the outer ear canal is described.     

Effect of the mediterranean diet with and without weight loss on markers of inflammation in men with metabolic syndrome

Objective:

Intervention studies on the Mediterranean Diet (MedDiet) have often led to weight loss, which may have contributed to the purported anti‐inflammatory effects of the MedDiet. To investigate the impact of the MedDiet consumed under controlled feeding conditions before (?WL) and after weight loss (+WL) on markers of inflammation in men with metabolic syndrome (MetS).

Design and Methods:

Subjects (N = 26, male, 24–65 years) with MetS first consumed a North American control diet for 5 weeks followed by a MedDiet for 5 weeks both in isocaloric feeding conditions. After a 20‐week weight loss period in free‐living conditions (10 ± 3% reduction in body weight, P < 0.01), participants consumed the MedDiet again under isocaloric‐controlled feeding condition for 5 weeks.

Results:

MedDiet ? WL significantly reduced plasma C‐reactive protein (CRP) concentrations (?26.1%, P = 0.02) and an arbitrary inflammatory score (?9.9%, P = 0.01) that included CRP, interleukin‐6 (IL‐6), IL‐18, and tumor necrosis factor‐α (TNF‐α) compared with the control diet. The MedDiet + WL significantly reduced plasma IL‐6 (?20.7%) and IL‐18 (?15.6%, both P ≤ 0.02) concentrations compared with the control diet but had no further significant impact on plasma CRP concentration. Participants with a reduction in waist circumference ≥8.5 cm after MedDiet + WL showed significantly greater reductions in inflammation markers than those with a change in waist circumference <8.5 cm.

Conclusions:

Thus, consuming MedDiet even in the absence of weight loss significantly reduces inflammation. However, the degree of waist circumference reduction with weight loss magnifies the impact of the MedDiet on other markers of inflammation associated with MetS in men.

     

Eukaryotic signaling pathways targeted by <Emphasis Type="Italic">Salmonella</Emphasis> effector protein AvrA in intestinal infection <Emphasis Type="Italic">in vivo</Emphasis>

Background  

The Salmonella AvrA gene is present in 80% of Salmonella enterica serovar strains. AvrA protein mimics the activities of some eukaryotic proteins and uses these activities to the pathogen's advantage by debilitating the target cells, such as intestinal epithelial cells. Therefore, it is important to understand how AvrA works in targeting eukaryotic signaling pathways in intestinal infection in vivo. In this study, we hypothesized that AvrA interacts with multiple stress pathways in eukaryotic cells to manipulate the host defense system. A whole genome approach combined with bioinformatics assays was used to investigate the in vivo genetic responses of the mouse colon to Salmonella with or without AvrA protein expression in the early stage (8 hours) and late stage (4 days). Specifically, we examined the gene expression profiles in mouse colon as it responded to pathogenic Salmonella stain SL1344 (with AvrA expression) or SB1117 (without AvrA expression).     

Attenuation of fibrosis <Emphasis Type="Italic">in vitro</Emphasis> and <Emphasis Type="Italic">in vivo</Emphasis> with <Emphasis Type="Italic">SPARC</Emphasis> siRNA

Introduction  

SPARC is a matricellular protein, which, along with other extracellular matrix components including collagens, is commonly over-expressed in fibrotic diseases. The purpose of this study was to examine whether inhibition of SPARC can regulate collagen expression in vitro and in vivo, and subsequently attenuate fibrotic stimulation by bleomycin in mouse skin and lungs.     

Potential biological control of Erwinia tracheiphila by internal alimentary canal interactions in Acalymma vittatum with Pseudomonas fluorescens

Aims

We aim to determine if Pseudomonas fluorescens is a viable biological control for Erwinia tracheiphila within the insect vector, Acalymma vittatum.

Methods and Results

Pseudomonas fluorescens secreted fluorescein and inhibited growth of E. tracheiphila in disc diffusion assays. To determine if this antagonism was conserved within the insect vector, we performed in vivo assays by orally injecting beetles with bacterial treatments and fluorescent in situ hybridization to determine bacterial presence within the alimentary canal.

Conclusions

Pseudomonas fluorescens inhibited the growth of E. tracheiphila on a nutrient‐limiting medium. In situ experiments demonstrated that P. fluorescens is maintained within the alimentary canal of the beetle for at least 4 days, and co‐occurred with E. tracheiphila. When beetles were first presented with Pseudomonas and then challenged with E. tracheiphila, E. tracheiphila was not recovered via FISH after 4 days. These data suggest that P. fluorescens has potential as a biological control agent to limit E. tracheiphila within the insect vector.

Significance and Impact of the Study

This is a novel approach for controlling E. tracheiphila that has the potential to decrease reliance on insecticides, providing a safer environment for pollinators and growers.