Monthly Archives: March 2016

Combining computer analysis with microscopy

OLYMPUS DIGITAL CAMERA31 March 2016:

CNBP researchers have successfully combined computer analysis with microscopy, to extract highly detailed cellular information that will help distinguish between healthy and diseased cells, in areas as diverse as cancer, injury and inflammation.

The approach, reported in the journal ‘Scientific Reports’, has shown that subtle biochemical signatures of cells can be captured and then categorized, to an extent that has never been seen before.

Paper Title: Quantitative non-invasive cell characterisation and discrimination based on multispectral autofluorescence features.

Authors: Martin E. Gosnell, Ayad G. Anwer, Saabah B. Mahbub, Sandeep Menon Perinchery, David W. Inglis, Partho P. Adhikary, Jalal A. Jazayeri, Michael A. Cahill, Sonia Saad, Carol A. Pollock, Melanie L. Sutton-McDowall, Jeremy G. Thompson & Ewa M. Goldys.

Abstract: Automated and unbiased methods of non-invasive cell monitoring able to deal with complex biological heterogeneity are fundamentally important for biology and medicine. Label-free cell imaging provides information about endogenous autofluorescent metabolites, enzymes and cofactors in cells. However extracting high content information from autofluorescence imaging has been hitherto impossible. Here, we quantitatively characterise cell populations in different tissue types, live or fixed, by using novel image processing and a simple multispectral upgrade of a wide-field fluorescence microscope. Our optimal discrimination approach enables statistical hypothesis testing and intuitive visualisations where previously undetectable differences become clearly apparent. Label-free classifications are validated by the analysis of Classification Determinant (CD) antigen expression. The versatility of our method is illustrated by detecting genetic mutations in cancer, non-invasive monitoring of CD90 expression, label-free tracking of stem cell differentiation, identifying stem cell subpopulations with varying functional characteristics, tissue diagnostics in diabetes, and assessing the condition of preimplantation embryos.

The research paper is accessible online. A CNBP media release is also available.

 

National Press Club: Women of Science

High Res Edit 008930 March 2016:

CNBP Chief Investigator Prof. Tanya Monro was one of three top tier scientists presenting today, at the Australian National Press Club in Canberra. The topic under discussion, gender inequalities in the scientific workplace and what can be done to best stop the science brain drain that is forcing out some of Australia’s best and most talented minds.

Joining Prof. Tanya Monro in discussion, were Professors Emma Johnston and Nalini Joshi.

You can view the full Press Club address from these three inspiring scientists via this ABC online stream.

 

Cytotoxic effects of upconversion nanoparticles

andrewzvyagin29 March 2016:

A/Prof Andrei Zvyagin, CNBP Associate Investigator located at Macquarie University, is co-author on the following nanoparticle focused paper, published in the journal ‘RSC Advances’.

Paper title: Cytotoxic effects of upconversion nanoparticles in primary hippocampal cultures.

Paper authors: Maria V Vedunova, Tatiana A Mishchenko, Elena V Mitroshina, Natalia V Ponomareva, Andrei V Yudintsev, Alla N Generalova, Sergey M Deyev, Irina V Mukhina, Alexey V Semyanov and Andrei V Zvyagin.

Abstract: The widespread use of nanomaterials causes public concerns associated with their potential toxicological hazards. New-generation nanomaterials – upconversion nanoparticles (UCNPs) – hold promise for theranostics applications due to their unique optical properties, enabling imaging at the sub-centimetre depth in live biological tissue. In brain tissue, nanoparticle-aided optical imaging and treatment are deemed desirable. To this aim, we carried out cytotoxicity studies of UCNPs in primary hippocampal cultures. The most common core/shell UCNPs (NaYF4:Yb3+:Tm3+/NaYF4) were synthesized using
a solvothermal method and hydrophilized with amphiphilic polymaleic anhydride Octadecene (PMAO); polyethyleneimine (PEI). Bare UCNPs were produced by using tetramethyl ammonium hydroxide (TMAH). PMAO-, PEI- and TMAH-UCNPs (0.8 mg mL 1) were incubated for 72 hours with primary hippocampal culture and exhibited noticeable cytotoxicity. Our studies showed profound morphological modification of all treated cells with the maximum and minimum uptake observed in PMAO- and TMAH-UCNPtreated
cells, respectively. The spontaneous calcium activity in cells treated with TMAH-UCNP, PMAOUCNP dropped to (17 3)%, (6 3)% of its original level and was completely inhibited in the PEI-UCNP treated cultures. This study demonstrated that bare and polymer surface-coated upconversion nanoparticles are toxic to dissociated hippocampal cells, evident through aberrant morphological changes, deviant variations of Ca2+ activity, and cell death.

The paper can be accessed online.

 

Paper looks at magneto plasmonic nanoantennas

Ivan Maksymov Low Res Edit 014725 March 2016:

Novel magneto-plasmonic nanoantennas are the focus of attention in the latest paper published by CNBP researcher Ivan Maksymov in the journal ‘Reviews in Physics’.

Title: Magneto-Plasmonic Nanoantennas: Basics and Applications.

Author: Ivan S. Maksymov

Abstract: Plasmonic nanoantennas is a hot and rapidly expanding research field. Here we overview basic operating principles and applications of novel magneto-plasmonic nanoantennas, which are made of ferromagnetic metals and driven not only by light, but also by external magnetic fields. We demonstrate that magneto-plasmonic nanoantennas enhance the magneto-optical effects, which introduces additional degrees of freedom in the control of light at the nano-scale. This property is used in conceptually new devices such as magneto-plasmonic rulers, ultra-sensitive biosensors, one-way subwavelength waveguides and extraordinary optical transmission structures, as well as in novel biomedical imaging modalities. We also point out that in certain cases ’non-optical’ ferromagnetic nanostructures may operate as magneto-plasmonic nanoantennas. This undesigned extra functionality capitalises on established optical characterisation techniques of magnetic nanomaterials and it may be useful for the integration of nanophotonics and nanomagnetism on a single chip.

The paper is accessible online.

 

Paper published in journal ‘Energies’

jingxianyu23 March 2016:

Jingxian Yu, CNBP Research Fellow is co-author  on a new paper published in the journal ‘Energies’.

Paper title: Electrochemical Mechanism for FeS2/C Composite in Lithium Ion Batteries with Enhanced Reversible Capacity.

Authors: Shengping Wang and Jingxian Yu

Abstract: Nanoscale FeS2 was synthesized via a simple hydrothermal method and was decorated by hydrothermal carbonization (FeS2@C). The structural properties of the synthesized materials detected by X-ray diffraction (XRD), together with the morphologies characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that the hydrothermal carbonization only had an impact on the morphology of pyrite. Additionally, the electrochemical performance of the coated pyrite in Li/FeS2 batteries was evaluated by galvanostatic discharge-charge tests and electrochemical impedance spectroscopy (EIS). The results showed that the initial capacity of FeS2@C was 799.2 mAh·g−1 (90% of theoretical capacity of FeS2) and that of uncoated FeS2 was only 574.6 mAh·g−1. XRD and ultraviolet (UV) visible spectroscopy results at different depths of discharge-charge for FeS2 were discussed to clarify the electrochemical mechanism, which play an important part in Li/FeS2 batteries.

The paper is accessible online.

Sensing for lithium ions

Daniel Stubing High Res Edit 005521 March 2016:

CNBP researchers Daniel Stubing, Sabrina Heng and Andrew Abell recently published a full paper in the journal ‘Organic and Biomolecular Chemistry’.

The published work presents three new spiropyran photoswitchable sensors and compares their sensitivity to different monovalent metal ions to develop a new reversible lithium ion sensor. These sensing molecules are now able to be further used to create optical devices for the sensing of biological lithium ions, which could help further understanding and treatment of neurological diseases such as manic-depressive illness.

Title: Crowned spiropyran fluoroionophores with a carboxyl moiety for the selective detection of lithium ions

Authors: D. B. Stubing, S. Heng and A. D. Abell

Abstract: The absorbance and fluorescence spectra of carboxylated spiropyrans containing methyl-1-aza-12-crown-4, methyl-1-aza-15-crown-5, methyl-1-aza-18-crown-6 moieties are compared. Characteristic changes in spectra after addition of the alkali metal salts of Li+, Na+, K+ and Cs+ were observed. Chromism induced by the binding of the metal cations was observed as an increase in absorbance and fluorescence. Of these metal cations, the Li+ ion produced the largest change in all three spiropyran systems. Reversible photoswitching of the spiropyran-metal complexes was observed on irradiation with alternating 352 nm UV and white light. This results in reversible fluorescence based sensing of lithium ions with potential for use in a biological sensor device.

The paper is accessible online.

 

Best paper award at SPIE Photonics West

Antony_Orth_web18 March 2016:

Congratulations to CNBP Research Fellow Antony Orth who has won a Hitachi Hi-Tech award for a paper presented at the recent SPIE Photonics West BIOS 2016 conference (High-Speed Biomedical Imaging and Spectroscopy: Toward Big Data Instrumentation and Management).

There were six awards distributed to authors who presented at the conference, with Antony’s talk titled “Gigapixel microscopy with microlens arrays.”

Awarded participants had to be both the primary author and presenter of an accepted abstract to be eligible. Qualifying papers and presentations were then evaluated by the awards committee.

Well done on your award Antony!

Proteomics paper examines knee osteoarthritis

Arun215 March 2016:

CNBP researcher Arun  Everest-Dass and CNBP Chief Investigator Prof Nicolle Packer have both co-authored a newly published paper that reports on a new approach, to better study and understand knee osteoarthritis. The paper was published in the journal ‘Proteomics’.

Title: MALDI mass spectrometry imaging of N-glycans on tibial cartilage and subchondral bone proteins in knee osteoarthritis.

Authors: Matthew T Briggs, Julia S Kuliwaba, Dzenita Muratovic, Arun V Everest-Dass, Nicolle H Packer, David M Findlay and Peter Hoffmann.

Abstract: Magnetic Resonance Imaging (MRI) is a non-invasive technique routinely used to investigate pathological changes in knee osteoarthritis (OA) patients. MRI uniquely reveals zones of the most severe change in the subchondral bone (SCB) in OA, called bone marrow lesions (BMLs). BMLs have diagnostic and prognostic significance in OA, but MRI does not provide a molecular understanding of BMLs. Multiple N-glycan structures have been observed to play a pivotal role in the OA disease process. We applied matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) of N-glycans to formalin-fixed paraffin-embedded (FFPE) SCB tissue sections from patients with knee OA, and liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) was conducted on consecutive sections to structurally characterize and correlate with the N-glycans seen by MALDI-MSI. The application of this novel MALDI-MSI protocol has enabled the first steps to spatially investigate the N-glycome in the SCB of knee OA patients.

The paper can be accessed online.

 

Prof Leonard Harrison visits Macquarie

Shaz_low-rez14 March 2016:

Prof Leonard Harrison from the Walter and Eliza Hall Institute of Medical Research (Melbourne) has given an invited talk to researchers at Macquarie University.

Invited by CNBP PhD student Abdulrahman (Shaz) Mansour M Shathili and CNBP Chief Investigator Prof Nicki Packer, Prof Harrison spoke about his work on a novel immunoregulatory mechanism whereby soluble CD52, released from activated T cells, suppresses other T cells and innate immune cells via Siglec receptor pathways.

Also discussed was the therapeutic potential resulting from this investigation.

 

Tanya Monro at WOMADelaide

High Res Edit 008914 March 2016:

One of Australia’s favourite outdoor festivals –  WOMADelaide -has featured CNBP Advocate and CI Tanya Monro.

Tanya joined internationally celebrated American academic and award winning author, Naomi Oreskes and Australia’s Dr Karl Kruzelnicki, in a panel discussion that examined the theme – ‘Should We Trust Scientists?’

The discussion featured as part of the WOMADelaide Planet Talks 2016 program and can be viewed online in its entirety.

Some of the big questions asked of the panel – Who should we trust and why? When should we accept what scientists say? How is that scientists do not always agree when analyzing the same information? Issues covered – the role of deep empathy, big brains and peer reviewed consideration.