<Emphasis Type="Italic">In Vivo</Emphasis> Phage Display Selection Yields Atherosclerotic Plaque Targeted Peptides for Imaging

Purpose Atherosclerosis is a leading cause of morbidity and mortality in the Western world, yet specific imaging agents to detect and map inflammatory plaques are still lacking.Procedures We used in vivo phage display to interrogate early atherosclerotic lesions present in ApoE−/− mice with the goal of identifying plaque-associated endothelial cell internalized affinity ligands.Results We identified 30 phage families with some of these families exhibiting homology to known atherosclerotic proteins, namely, leukemia inhibitory factor, transferrin, and VLA-4. VLA-4 homologous peptides [termed vascular cellular adhesion molecule-1 (VCAM-1) internalizing peptide-28 (VINP₂₈)] bound to and were internalized by VCAM-1-expressing cells and were inhibited by soluble VCAM-1. In addition, a VINP₂₈ modified multimodal nanoparticle showed high affinity for endothelial cells expressing VCAM-1 but low affinity for macrophages or smooth muscle cells.Conclusion The identified peptides represent a set of probes to interrogate the cell surface repertoire and potentially allow early detection of atherosclerosis.     

Motion-Artifact-Free <Emphasis Type="Italic">In Vivo</Emphasis> Imaging Utilizing Narcotized Avian Embryos <Emphasis Type="Italic">In Ovo</Emphasis>

Purpose  

The chick embryo in ovo is a well-accessible and economical in vivo model, but its use in molecular imaging has been limited because of motion artifacts on resulting images. The purpose of this study was to develop a method using narcotics to inhibit motility and to perform motion-artifact-free imaging of living chick embryos in ovo.     

<Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis> Comparison of Selected Ga-68 and Zr-89 Labelled Siderophores

Purpose

Some [⁶⁸Ga]siderophores show promise in specific and sensitive imaging of infection. Here, we compare the in vitro and in vivo behaviour of selected Ga-68 and Zr-89 labelled siderophores.

Procedures

Radiolabelling was performed in HEPES or sodium acetate buffer systems. Radiochemical purity of labelled siderophores was determined using chromatography. Partition coefficients, in vitro stability and protein binding affinities were determined. Ex vivo biodistribution and animal imaging was studied in mice.

Results

Certain differences among studied siderophores were observed in labelling efficiency. Protein binding and stability tests showed highest stabilities and lowest protein binding affinities for Ga-68 and [⁸⁹Zr]triacetylfusarinine C (TAFC). All studied Ga-68 and [⁸⁹Zr]siderophores exhibited a similar biodistribution and pharmacokinetics in mice with the exception of [⁸⁹Zr]ferrioxamine E (FOXE).

Conclusions

Zr-89 and [⁶⁸Ga]siderophores showed analogous in vitro and in vivo behaviour. Tested [⁸⁹Zr]siderophores could be applied for longitudinal positron emission tomography (PET) studies of fungal infections and especially TAFC for the development of novel bioconjugates.

     

Not <Emphasis Type="Italic">if</Emphasis> but <Emphasis Type="Italic">when</Emphasis>; no longer <Emphasis Type="Italic">why</Emphasis> but <Emphasis Type="Italic">how</Emphasis>

There is accruing evidence that information technology can improve patient health care, with several trials of technology showing smaller numbers of medication errors, or can provide earlier detection of adverse events. Critics of this type of research point out that better resolution of events is of no value unless their direct management influences clinical outcome. Nevertheless, indirect evidence is available, such as reports indicating the importance of providing specialist neuro-critical care in the management of patients with traumatic brain injury. These studies do not indicate which aspects of critical care management are crucial, but management aimed at the earlier detection and treatment of adverse events must be partly responsible. We continue to hope for definitive controlled trial evidence that information technology-led management yields improved patient outcome, but our experience so far of funding and conducting such studies has been poor. There is no question that we need better monitoring and event detection technology for health care and that we need more research into optimising that technology, but should their adoption depend on large-scale clinical trials? Perhaps now the questions we need to focus upon are no longer if but when, and no longer why but how.     

Detection of Enzyme Activity and Inhibition during Studies in Solution, <Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis> with CatalyCEST MRI

Purpose

The detection of enzyme activities and evaluation of enzyme inhibitors have been challenging with magnetic resonance imaging (MRI). To address this need, we have developed a diamagnetic, nonmetallic contrast agent and a protocol known as catalyCEST MRI that uses chemical exchange saturation transfer (CEST) to detect enzyme activity as well as enzyme inhibition.

Procedures

We synthesized a diamagnetic MRI contrast agent that has enzyme responsive and enzyme unresponsive CEST signals. We tested the ability of this agent to detect the activity of kallikrein 6 (KLK6) in biochemical solutions, in vitro and in vivo, with and without a KLK6 inhibitor.

Results

The agent detected KLK6 activity in solution and also detected KLK6 inhibition by antithrombin III. KLK6 activity was detected during in vitro studies with HCT116 colon cancer cells, relative to the detection of almost no activity in a KLK6-knockdown HCT116 cell line and HCT116 cells treated with antithrombin III inhibitor. Finally, strong enzyme activity was detected within an in vivo HCT116 tumor model, while lower enzyme activity was detected in a KLK6 knockdown tumor model and in the HCT116 tumor model treated with antithrombin III inhibitor. In all cases, comparisons of the enzyme responsive and enzyme unresponsive CEST signals were critical for the detection of enzyme activity.

Conclusions

This study has established that catalyCEST MRI with an exogenous diaCEST agent can evaluate enzyme activity and inhibition in solution, in vitro and in vivo.

     

Synthesis and <Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis> Evaluation of [<Superscript>3</Superscript>H]LRRK2-IN-1 as a Novel Radioligand for LRRK2

Purpose

LRRK2 (leucine-rich repeat kinase 2) has recently been proven to be a promising drug target for Parkinson’s disease (PD) due to an apparent enhanced activity caused by mutations associated with familial PD. To date, there have been no reports in which a LRRK2 inhibitor has been radiolabeled and used for in in vitro or in vivo studies of LRRK2. In the present study, we radiolabeled the LRRK2 ligand, LRRK-IN-1, for the purposes of performing in vitro (IC₅₀, K _d , B _max, autoradiography) and in vivo (biodistribution, and blocking experiments) evaluations in rodents and human striatum tissues.

Procedures

[³H]LRRK2-IN-1 was prepared with high radiochemical purity (>99 %) and a specific activity of 41 Ci/mmol via tritium/hydrogen (T/H) exchange using Crabtree’s catalyst. For IC⁵⁰, K _d , and B _max determination, LRRK2-IN-1 was used as a competing drug for nonspecific binding assessment. The specific binding of the tracer was further evaluated via an in vivo blocking study in mice with a potent LRRK2 inhibitor, Pf-06447475.

Results

In vitro binding studies demonstrated a saturable binding site for [³H]LRRK2-IN-1 in rat kidney, rat brain striatum and human brain striatum with K _d of 26 ± 3 and 43 ± 8, 48 ± 2 nM, respectively. In rat, the density of LRRK2 binding sites (B _max) was higher in kidney (6.4 ± 0.04 pmol/mg) than in brain (2.5 ± 0.03 pmol/mg), however, in human brain striatum, the B _max was 0.73 ± 0.01 pmol/mg protein. Autoradiography imaging in striatum of rat and human brain tissues gave results consistent with binding studies. In in vivo biodistribution and blocking studies in mice, co-administration with Pf-06447475 (10 mg/kg) reduced the uptake of [³H]LRRK2-IN-1 (%ID/g) by 50–60% in the kidney or brain.

Conclusion

The high LRRK2 brain density observed in our study suggests the feasibility for positron emission tomography imaging of LRRK2 (a potential target) with radioligands of higher affinity and specificity.

     

<Emphasis Type="Italic">In vitro</Emphasis> and <Emphasis Type="Italic">in vivo</Emphasis> evaluation of a new active heat moisture exchanger

Introduction  

In order to improve the efficiency of heat moisture exchangers (HMEs), new hybrid humidifiers (active HMEs) that add water and heat to HMEs have been developed. In this study we evaluated the efficiency, both in vitro and in vivo, of a new active HME (the Performer; StarMed, Mirandola, Italy) as compared with that of existing HMEs (Hygroster and Hygrobac; Mallinckrodt, Mirandola, Italy).     

Impact of Indium-111 Oxine Labelling on Viability of Human Mesenchymal Stem Cells <Emphasis Type="Italic">In Vitro</Emphasis>, and 3D Cell-Tracking Using SPECT/CT <Emphasis Type="Italic">In Vivo</Emphasis>

Purpose  

This study investigates the effects of ¹¹¹In-oxine incorporation on human mesenchymal stem cells’ (hMSC) biology and viability, and the applicability of ¹¹¹In-oxine for single-photon emission computed tomography/X-ray computed tomography (SPECT/CT) monitoring of hMSC in vivo.     

Tissue Culture Independent <Emphasis Type="Italic">Agrobacterium tumefaciens</Emphasis> Mediated <Emphasis Type="Italic">In Planta</Emphasis> Transformation Method for Tropical Maize (<Emphasis Type="Italic">Zea mays.L</Emphasis>)

Tropical maize is recalcitrant to tissue culture regeneration because of its poor response to in vitro regeneration after transformation. In this context, the present study has developed the tissue culture independent in planta transformation protocol for tropical maize by transferring plumular meristem cells of germinating seeds of tropical maize genotype through Agrobacteriumtumefaciens infection. The protocol was developed by using Agrobacterium strain EHA105 containing vector pCAMBIA3301 carrying cry1Ab, gus and bar genes. The expression of transgene gus in T₀ plants was confirmed by measuring the hydrolysis rate of the fluorescent substrate 4-methylumbelliferyl-beta-D-glucuronide (MUG) assay whereas the presence of cry1Ab gene was confirmed by polymerase chain reaction and T₀ plants were allowed to grow in glass house into whole plant until maturity and were selfed to produce seeds of T₁ generation. The presence of transgene and its segregation was studied in T₁ generation through Southern and enzyme-linked immunosorbent assay confirming the presence of transgene and its expression respectively. The developed protocol is cost-effective, efficient and genotype independent without involvement of any tissue culture procedure and can generate a relatively large number of transgenic plants in approximately 75–90 days.     

Larvicidal Activity of <Emphasis Type="Italic">Colocasia esculenta,Eclipta prostrata</Emphasis> and <Emphasis Type="Italic">Wrightia tinctoria</Emphasis> Leaf Extract Against <Emphasis Type="Italic">Culex quinquefasciatus</Emphasis>

Control of mosquitoes by using chemical insecticides creates several problems including development of resistance. This leads to find out alternative methods via plant products. Viewing this in mind, methanolic extracts of Colocasia esculenta, Eclipta prostrata and Wrightia tinctoria leaves were tested against II, III, IV instars and pupa of filarial vector Culex quinquefasciatus. The LC₅₀ value obtained for IV instar larvae of Cx. quinquefasciatus is 165.697 ppm for C. esculenta while it is 114.257 ppm for E. prostrata and 210.298 ppm for W. tinctoria. Of the three plants studied E. prostrata is most effective in controlling mosquito larvae than the others.     

DNA Barcodes Distinguish <Emphasis Type="Italic">Withania somnifera</Emphasis> and <Emphasis Type="Italic">Withania ashwagandha</Emphasis>

On the basis of morphology, chemical profiling, crossing ability, amplified fragment length polymorphism and comparison of nucleotide sequences of nuclear ribosomal internal transcribed spacer (ITS), the cultivated form of Withania somnifera, a species of therapeutic value, has been circumscribed as a new species, Withania ashwagandha. The present study was undertaken to ascertain whether the two species can be distinguished on the basis of DNA barcoding. Six barcode loci, ITS, ITS2, matK (maturase K), rbcL (ribulose-bisphosphate carboxylase/oxygenase, large subunit), rpoC1 (RNA polymerase-β′ subunit, main catalytic subunit) and trnH-psbA spacer (transfer RNA for histidine-photosystem II protein D1 spacer) from W. somnifera, W. ashwagandha, their hybrid, and ‘ashwagandha’ market samples were amplified, sequenced, and compared. ITS, ITS2 and matK distinguished two species on the basis of phylogenetic tree method. Likewise, BLAST 1 analysis based on ITS, ITS2, matK, and rbcL individually discriminated two species. However, on the basis of Kimura 2 Parameter distances, two species could not be distinguished as the requirement of a distinct barcode gap—the highest intraspecific distance being lower than the lowest interspecific distance—was not met by any of the loci. If compared by character-based method, ITS, ITS2 and matK sequences of the two species had distinct diagnostic nucleotides (pure character attributes) at nine, four and one positions, respectively. Interestingly, all market samples co-segregated and shared character attributes with W. ashwagandha.     

Morphogenetic Studies on Two Mosses, <Emphasis Type="Italic">Bryum dichotomum</Emphasis> and <Emphasis Type="Italic">Entodon macropodus</Emphasis> Grown In Vitro

Axenic cultures of two moss taxa viz. Bryum dichotomum Hedw., an acrocarpous moss and Entodon macropodus (Hedw.) Müll. Hal., a pleurocarpous moss were established by inoculating their spores into agar media. Germination, growth, development and comparative morphogenetic studies of these two growth forms were done. In B. dichotomum, protonemal buds developed on caulonema, while in E. macropodus, buds were produced on chloronema. Sub culturing of B. dichotomum gave rise to new individuals through chloronemal and caulonemal stage, while E. macropodus it directly regenerated into new gametophytes. In old culture under low moisture conditions, asexual diaspores namely, protonemal bulbils B. dichotomum and protonemal brood cells E. macropodus were formed.     

Seeing SPIOs Directly <Emphasis Type="Italic">In Vivo</Emphasis> with Magnetic Particle Imaging

Magnetic particle imaging (MPI) is a new molecular imaging technique that directly images superparamagnetic tracers with high image contrast and sensitivity approaching nuclear medicine techniques—but without ionizing radiation. Since its inception, the MPI research field has quickly progressed in imaging theory, hardware, tracer design, and biomedical applications. Here, we describe the history and field of MPI, outline pressing challenges to MPI technology and clinical translation, highlight unique applications in MPI, and describe the role of the WMIS MPI Interest Group in collaboratively advancing MPI as a molecular imaging technique. We invite interested investigators to join the MPI Interest Group and contribute new insights and innovations to the MPI field.     

<Emphasis Type="Italic">In Vivo</Emphasis> Mouse Bioluminescence Tomography with Radionuclide-Based Imaging Validation

Introduction  

Bioluminescence imaging, especially planar bioluminescence imaging, has been extensively applied in in vivo preclinical biological research. Bioluminescence tomography (BLT) has the potential to provide more accurate imaging information due to its 3D reconstruction compared with its planar counterpart.     

First Attempt of Complete Rearing of Tea Looper, <Emphasis Type="Italic">Biston</Emphasis> (=<Emphasis Type="Italic">Buzura</Emphasis>)<Emphasis Type="Italic"> suppressaria</Emphasis>, on Artificial and Natural Diet

Complete rearing of the looper pest, Biston (=Buzura) suppressaria (Guen.) (Lepidoptera: Geometridae) through generations has been attempted for the first time on artificial diet as an alternative to tea-leaf diet. A comparative study on performance of the pest on its natural host, tea (Camellia sinensis, O’Kuntz), and on the newly formulated artificial diet revealed adequacy and superiority of the latter diet. The development period of B. suppressaria was shorter (48 days) on artificial diet, with a better survival rate than that on tea. On artificial diet the species showed a greater effective rearing rate with production of heavier pupae and adults. Nutritional indices determined for advanced looper stage tilted in favour of artificial diet as compared to that on tea with significantly higher relative growth rate, efficiency of conversion of ingested food, efficiency of conversion of digested food, approximate digestibility, production index and significantly lower maintenance cost.     

<Emphasis Type="Italic">In silico</Emphasis> Analysis of Synonymous Codon Usage Pattern of <Emphasis Type="Italic">Rhizobium etli</Emphasis> CFN 42

Understanding the extent and pattern of codon bias and the forces affecting codon usage are the key steps towards elucidating choice of codons at the level of individual genes. In the present study, codon usage pattern among 3,703 genes of nitrogen fixing bacterium, Rhizobium etli CFN 42 was analyzed. The study aims to identify the factors responsible for codon usage bias and highly expressed genes of this bacterium. Multivariate statistical analysis revealed a single major explanatory axis accounting for codon usage variation among the genes. Correlation analysis suggested that the axis has strong significant positive correlation with GC_3s i.e. GC content at the third codon position. A significant negative correlation between effective number of codons and GC_3s content was observed suggesting that the codon usage was affected by gene nucleotide composition. These findings suggested mutational role as the major factor in shaping codon usage bias among the genes. Further, correspondence analysis of Relative Synonymous Codon Usage revealed cluster of highly expressed genes. Notably, 26 codons were determined as the ‘optimal codons’ that were significantly more frequent among the highly expressed genes tested by χ² test (P < 0.01). Such results may add value to the efforts of developing bio-fertilizers based on symbiotic or non-symbiotic bacteria for improving soil fertility.