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The zoonotic Plasmodium knowlesi parasite is a growing public health concern in Southeast Asia, especially in Malaysia, where elimination of P. falciparum and P. vivax malaria has been the focus of control efforts. Understanding of the genetic diversity of P. knowlesi parasites can provide insights into its evolution, population structure, diagnostics, transmission dynamics, and the emergence of drug resistance. Previous work has revealed that P. knowlesi fall into three main sub-populations distinguished by a combination of geographical location and macaque host (Macaca fascicularis and M. nemestrina). It has been shown that Malaysian Borneo groups display profound heterogeneity with long regions of high or low divergence resulting in mosaic patterns between sub-populations, with some evidence of chromosomal-segment exchanges. However, the genetic structure of non-Borneo sub-populations is less clear. By gathering one of the largest collections of P. knowlesi whole-genome sequencing data, we studied structural genomic changes across sub-populations, with the analysis revealing differences in Borneo clusters linked to mosquito-related stages of the parasite cycle, in contrast to differences in host-related stages for the Peninsular group. Our work identifies new genetic exchange events, including introgressions between Malaysian Peninsular and M. nemestrina-associated clusters on various chromosomes, including in parasite invasion genes (DBP$$\beta$$ β , NBPX$$\alpha$$ α and NBPX$$\beta$$ β ), and important proteins expressed in the vertebrate parasite stages. Recombination events appear to have occurred between the Peninsular and M. fascicularis-associated groups, including in the DBP$$\beta$$ β and DBP$$\gamma$$ γ invasion associated genes. Overall, our work finds that genetic exchange events have occurred among the recognised contemporary groups of P. knowlesi parasites during their evolutionary history, leading to apparent mosaicism between these sub-populations. These findings generate new hypotheses relevant to parasite evolutionary biology and P. knowlesi epidemiology, which can inform malaria control approaches to containing the impact of zoonotic malaria on human communities.

Understanding the response of bacteria to environmental stress is hampered by the relative insensitivity of methods to detect growth. This means studies of antibiotic resistance and other physiological methods often take 24 h or longer. We developed and tested a scattered light and detection system (SLIC) to address this challenge, establishing the limit of detection, and time to positive detection of the growth of small inocula. We compared the light-scattering of bacteria grown in varying high and low nutrient liquid medium and the growth dynamics of two closely related organisms. Scattering data was modelled using Gompertz and Broken Stick equations. Bacteria were also exposed meropenem, gentamicin and cefoxitin at a range of concentrations and light scattering of the liquid culture was captured in real-time. We established the limit of detection for SLIC to be between 10 and 100 cfu mL−1 in a volume of 1–2 mL. Quantitative measurement of the different nutrient effects on bacteria were obtained in less than four hours and it was possible to distinguish differences in the growth dynamics of Klebsiellapneumoniae 1705 possessing the BlaKPC betalactamase vs. strain 1706 very rapidly. There was a dose dependent difference in the speed of action of each antibiotic tested at supra-MIC concentrations. The lethal effect of gentamicin and lytic effect of meropenem, and slow bactericidal effect of cefoxitin were demonstrated in real time. Significantly, strains that were sensitive to antibiotics could be identified in seconds. This research demonstrates the critical importance of improving the sensitivity of bacterial detection. This results in more rapid assessment of susceptibility and the ability to capture a wealth of data on the growth dynamics of bacteria. The rapid rate at which killing occurs at supra-MIC concentrations, an important finding that needs to be incorporated into pharmacokinetic and pharmacodynamic models. Importantly, enhanced sensitivity of bacterial detection opens the possibility of susceptibility results being reportable clinically in a few minutes, as we have demonstrated.

This work was supported by the National Research Foundation of Korea (NRF) Grant funded by the Korea government (MSIT) (No. 2019R1A2C2011293) and the UK Engineering and Physical Sciences Research Council (Grant EP/P030017/1). We report a new method to optically manipulate a single dielectric particle along closed-loop polygonal trajectories by crossing a suite of all-fiber Bessel-like beams within a single water droplet. Exploiting optical radiation pressure, this method demonstrates the circulation of a single polystyrene bead in both a triangular and a rectangle geometry enabling the trapped particle to undergo multiple circulations successfully. The crossing of the Bessel-like beams creates polygonal corners where the trapped particles successfully make abrupt turns with acute angles, which is a novel capability in microfluidics. This offers an optofluidic paradigm for particle transport overcoming turbulences in conventional microfluidic chips. Publisher PDF

This work was supported by the British Heart Foundation (grant ref: FS/20/3/34956). Obesity is a complex disease that increases an individual’s risk of developing other diseases and health-related problems. A common feature is dyslipidemia characterized by increased levels of plasma lipids, which include non-esterified fatty acids (NEFAs). The role of NEFAs in obesity-related morbidity is interesting as NEFAs constitute a reservoir of metabolic energy, are principal components of cell membranes and are precursors for signalling molecules. Bariatric surgery promotes sustained weight loss in severely obese patients, reducing the incidence and severity of co-morbidities. In this study we measure changes in circulating NEFA species in plasma samples taken from 25 obese individuals before and 9 months after Roux-en-Y gastric bypass surgery. The mean weight of the cohort reduced by 29.2% from 149.0±25.1 kg pre-surgery to 105.5±19.8 kg post-surgery and the BMI by 28.2% from 51.8±6.3 kg/m2 pre-surgery to 37.2±5.4 kg/m2. Mean glycated haemoglobin (HbA1c) reduced from 6.5±1.3% to 5.5±0.5%, consistent with the intervention leading to improved glycaemic control, particularly in those who were dysglycemic prior to surgery. Total and LDL cholesterol concentrations were markedly reduced following surgery. Concentrations of seven NEFAs were found to decrease 9 months after surgery compared to pre-surgery levels: myristate, palmitoleate, palmitate, linoleate, oleate, stearate and arachidonate. Bariatric surgery led to increased lipogenesis and elongase activity and decreased stearoyl-CoA desaturase 1 activity. This study thus highlights metabolic changes that take place following gastric bypass surgery in severely obese patients. Publisher PDF

This work was supported by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 812777 Differences in the expression patterns of genes have been used to measure the effects of non-stress or stress conditions in poultry species. However, the list of genes identified can be extensive and they might be related to several biological systems. Therefore, the aim of this study was to identify a small set of genes closely associated with stress in a poultry animal model, the chicken (Gallus gallus), by reusing and combining data previously published together with bioinformatic analysis and Bayesian networks in a multi-step approach. Two datasets were collected from publicly available repositories and pre-processed. Bioinformatics analyses were performed to identify genes common to both datasets that showed differential expression patterns between non-stress and stress conditions. Bayesian networks were learnt using a Simulated Annealing algorithm implemented in the software Banjo. The structure of the Bayesian network consisted of 16 out of 19 genes together with the stress condition. Network structure showed CARD19 directly connected to the stress condition plus highlighted CYGB, BRAT1, and EPN3 as relevant, suggesting these genes could play a role in stress. The biological functionality of these genes is related to damage, apoptosis, and oxygen provision, and they could potentially be further explored as biomarkers of stress. Publisher PDF

This work was supported by the BBSRC Grant BB/N006615/1. Body odour is a characteristic trait of Homo sapiens, however its role in human behaviour and evolution is poorly understood. Remarkably, body odour is linked to the presence of a few species of commensal microbes. Herein we discover a bacterial enzyme, limited to odour-forming staphylococci that are able to cleave odourless precursors of thioalcohols, the most pungent components of body odour. We demonstrated using phylogenetics, biochemistry and structural biology that this cysteine-thiol lyase (C-T lyase) is a PLP-dependent enzyme that moved horizontally into a unique monophyletic group of odour-forming staphylococci about 60 million years ago, and has subsequently tailored its enzymatic function to human-derived thioalcohol precursors. Significantly, transfer of this enzyme alone to non-odour producing staphylococci confers odour production, demonstrating that this C-T lyase is both necessary and sufficient for thioalcohol formation. The structure of the C-T lyase compared to that of other related enzymes reveals how the adaptation to thioalcohol precursors has evolved through changes in the binding site to create a constrained hydrophobic pocket that is selective for branched aliphatic thioalcohol ligands. The ancestral acquisition of this enzyme, and the subsequent evolution of the specificity for thioalcohol precursors implies that body odour production in humans is an ancient process. Publisher PDF

© The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/., Phospholipases are esterases involved in lipid catabolism. In pathogenic micro-organisms (bacteria, fungi, parasites) they often play a critical role in virulence and pathogenicity. A few phospholipases (PL) have been characterised so far at the gene and protein level in unicellular parasites including African trypanosomes (AT). They could play a role in different processes such as host-pathogen interaction, antigenic variation, intermediary metabolism. By mining the genome database of AT we found putative new phospholipase candidate genes and here we provided biochemical evidence that one of these has lipolytic activity. This protein has a unique non-canonical glycosome targeting signal responsible for its dual localisation in the cytosol and the peroxisomes-related organelles named glycosomes. We also show that this new phospholipase is excreted by these pathogens and that antibodies directed against this protein are generated during an experimental infection with T. brucei gambiense, a subspecies responsible for infection in humans. This feature makes this protein a possible tool for diagnosis., Experiment costs were supported by Université de Bordeaux (https://www.u-bordeaux.fr), CNRS (https://www.cnrs.fr) and the Agence Nationale de la Recherche through the grants GLYCONOV (grant number ANR-15-CE-15-0025-01) and ADIPOTRYP (grant number ANR19-CE15-0004-01). This work was also funded by the Laboratoire d’Excellence (LabEx) “French Parasitology Alliance For Health Care” (ANR-11-LABX-0024-PARAFRAP, https://labex-parafrap.fr). This work was also partially supported by the European Research Council (FatTryp, ref. 771714) and by Fundacao para a Ciencia e Tecnologia (CEECIND/03322/2018) awarded to LMF.

This project was supported by grants from the British Heart Foundation (PG/11/71/29091 and PG/16/68/31991) and the Orthopaedic Institute Ltd., (RJAH Orthopaedic Hospital, Oswestry, UK). Nesprins, nuclear envelope spectrin-repeat proteins encoded by the SYNE1 and SYNE2 genes, are involved in localization of nuclei. The short isoform, nesprin-1-alpha2, is required for relocation of the microtubule organizer function from centromeres to the nuclear rim during myogenesis. Using specific antibodies, we now show that both nesprin-1-alpha2 and nesprin-1-giant co-localize with kinesin at the junctions of concatenated nuclei and at the outer poles of nuclear chains in human skeletal myotubes. In adult muscle, nesprin-1-alpha2 was found, together with kinesin, only on nuclei associated with neuromuscular junctions, whereas all adult cardiomyocyte nuclei expressed nesprin-1-alpha2. In a proteomics study, kinesin heavy and light chains were the only significant proteins in myotube extracts pulled down by nesprin-1-alpha2, but not by a mutant lacking the highly-conserved STAR domain (18 amino-acids, including the LEWD motif). The results support a function for nesprin-1-alpha2 in the specific localization of skeletal muscle nuclei mediated by kinesins and suggest that its primary role is at the outer nuclear membrane. Publisher PDF

The aim of the study was to determine the efficacy of dual β-lactam combination treatments derived from eight approved drugs against Galleria mellonella larvae infected with MDR strains of P. aeruginosa. Carbapenem-resistant P. aeruginosa NCTC 13437 and an unrelated clinical isolate were used to infect G. mellonella larvae and the efficacy of twenty-eight dual β-lactam combination therapies were compared to their constituent monotherapies. For the most potent combinations identified, penicillin-binding protein (PBP) inhibition profiles were measured and compared with each constituent antibiotic. Five of the dual β-lactam combinations resulted in greater than 70% survival of infected G. mellonella. Two combinations showed potent, enhanced efficacy versus both strains − ceftazidime + meropenem and aztreonam + meropenem. Comparison of PBP inhibition profiles revealed that the enhanced efficacy of these two dual β-lactam combinations could not be explained by more potent inhibition of PBPs or inhibition of a broader range of PBPs. A possible contribution to the enhanced efficacy of the combinations could be stimulation of innate immunity via increased haemocyte numbers compared to their constituent monotherapies. Combinations of β-lactam antibiotics show promise in overcoming MDR P. aeruginosa and are worthy of additional study and development.

The authors want to acknowledge the financial support of the Polish National Science Centre under Grant No. 2017/25/N/ST7/01610, the Polish National Agency for Academic Exchange NAWA under Bilateral exchange of scientists between France and Poland PHC Polonium PPN/BFR/2019/1/00005/U/00001, Polish National Agency for Academic Exchange under Iwanowska Programme PPN/IWA/2018/1/00026/U/00001, Polish National Agency for Academic Exchange under Iwanowska Programme PPN/IWA/2018/1/00058/U/00001, and DS Programs of Faculty of Electronics, Telecommunications and Informatics of Gdańsk University of Technology. KD thanks the UK Engineering and Physical Sciences Research Council for funding (Grant EP/P030017/1). Fiber optic sensors are widely used in environmental, biological and chemical sensing. Due to the demanding environmental conditions in which they can be used, there is a risk of damaging the sensor measurement head placed in the measuring field. Sensors using nanolayers deposited upon the fiber structure are particularly vulnerable to damage. A thin film placed on the surface of the fiber end-face can be prone to mechanical damage or deteriorate due to unwanted chemical reactions with the surrounding agent. In this paper, we investigated a sensor structure formed with a Zinc Oxide (ZnO) coating, deposited by Atomic Layer Deposition (ALD) on the tip of a single-mode fiber. A nanocrystalline diamond sheet (NDS) attached over the ZnO is described. The diamond structure was synthesized in a Microwave Plasma Assisted Chemical Vapor Deposition System. The deposition processes of the nanomaterials, the procedure of attaching NDS to the fiber end-face covered with ZnO, and the results of optical measurements are presented. Publisher PDF

Funding: This work was supported by grant funding from BBSRC BB/M00337X/2 and BB/I000828/1. This research was also supported by the United States Department of Agriculture (USDA) National Institute of Food and Agriculture (NIFA) grant 2017-06481 (EVR). Deformed wing virus (DWV) is a persistent pathogen of European honey bees and the major contributor to overwintering colony losses. The prevalence of DWV in honey bees has led to significant concerns about spillover of the virus to other pollinating species. Bumble bees are both a major group of wild and commercially-reared pollinators. Several studies have reported pathogen spillover of DWV from honey bees to bumble bees, but evidence of a sustained viral infection characterized by virus replication and accumulation has yet to be demonstrated. Here we investigate the infectivity and transmission of DWV in bumble bees using the buff-tailed bumble bee Bombus terrestris as a model. We apply a reverse genetics approach combined with controlled laboratory conditions to detect and monitor DWV infection. A novel reverse genetics system for three representative DWV variants, including the two master variants of DWV - type A and B - was used. Our results directly confirm DWV replication in bumble bees but also demonstrate striking resistance to infection by certain transmission routes. Bumble bees may support DWV replication but it is not clear how infection could occur under natural environmental conditions. Publisher PDF

The authors acknowledge funding from the UK Engineering and Physical Sciences Research Council through grant EP/J01771X/1 The transversal profile of beams can always be defined as a superposition of orthogonal fields, such as optical eigenmodes. Here, we describe a generic method to separate the individual components in a laser beam and map each mode onto its designated detector with low crosstalk. We demonstrate this with the decomposition into Laguerre-Gaussian beams and introduce a distribution over the integer numbers corresponding to the discrete orbital and radial momentum components of the light field. The method is based on determining an eigenmask filter transforming the incident optical eigenmodes to position eigenmodes enabling the detection of the state of the light field using single detectors while minimizing cross talk with respect to the set of filter masks considered. Publisher PDF

A.S. is the recipient of a Medical Research Scotland PhD Studentship awarded to P.A.R. Edinburgh Genomics is partly supported through core grants from Natural Environment Research Council (R8/H10/56), Medical Research Council (MR/K001744/1) and Biotechnological and Biological Research Council (BB/J004243/1). Publication of this article was funded in part by the University of St Andrews Open Access Publishing Fund. Gemcitabine is a fluoropyrimidine analogue that is used as a mainstay of chemotherapy treatment for pancreatic and ovarian cancers, amongst others. Despite its widespread use, gemcitabine achieves responses in less than 10% of patients with metastatic pancreatic cancer and has a very limited impact on overall survival due to intrinsic and acquired resistance. NUC-1031 (Acelarin), a phosphoramidate transformation of gemcitabine, was the first anti-cancer ProTide to enter the clinic. We find it displays important in vitro cytotoxicity differences to gemcitabine, and a genome-wide CRISPR/Cas9 genetic screening approach identified only the pyrimidine metabolism pathway as modifying cancer cell sensitivity to NUC-1031. Low deoxycytidine kinase expression in tumour biopsies from patients treated with gemcitabine, assessed by immunostaining and image analysis, correlates with a poor prognosis, but there is no such correlation in tumour biopsies from a Phase I cohort treated with NUC-1031. Publisher PDF

Funding for this research was provided by the European Union’s Horizon 2020 research and innovation programme under grant agreement number 654428 (“CORBEL”) and a MASTS (Marine Alliance for Science and Technology Scotland) PECRE young investigator award to IMLS. This work was supported by the Branchiostoma lanceolatum genome consortium, which provided access to the Branchiostoma lanceolatum genome sequence. The Pax3/7 transcription factor family is integral to developmental gene networks contributing to important innovations in vertebrate evolution, including the neural crest. The basal chordate lineage of amphioxus is ideally placed to understand the dynamics of the gene regulatory network evolution that produced these novelties. We report here the discovery that the cephalochordate lineage possesses two Pax3/7 genes, Pax3/7a and Pax3/7b. The tandem duplication is ancestral to all extant amphioxus, occurring in both Asymmetron and Branchiostoma, but originated after the split from the lineage leading to vertebrates. The two paralogues are differentially expressed during embryonic development, particularly in neural and somitic tissues, suggesting distinct regulation. Our results have implications for the study of amphioxus regeneration, neural plate and crest evolution, and differential tandem paralogue evolution. Publisher PDF

B.L. acknowledges financial support from the Binational Science Foundation under grant No 2014396 and from the National Science Foundation under grant No 1639073. C.K. acknowledges funding from the Kent State University Internal Post-Doctoral Competition. M.C.K. acknowledges funding from the Belgian Agentschap voor innovatie door wetenschap en techniek under grant No IWT 131498. Liquid-crystalline organic semiconductors exhibit unique properties that make them highly interesting for organic optoelectronic applications. Their optical and electrical anisotropies and the possibility to control the alignment of the liquid-crystalline semiconductor allow not only to optimize charge carrier transport, but to tune the optical property of organic thin-film devices as well. In this study, the molecular orientation in a liquid-crystalline semiconductor film is tuned by a novel blading process as well as by different annealing protocols. The altered alignment is verified by cross-polarized optical microscopy and spectroscopic ellipsometry. It is shown that a change in alignment of the liquid-crystalline semiconductor improves charge transport in single charge carrier devices profoundly. Comparing the current-voltage characteristics of single charge carrier devices with simulations shows an excellent agreement and from this an in-depth understanding of single charge carrier transport in two-terminal devices is obtained. Finally, p-i-n type organic light-emitting diodes (OLEDs) compatible with vacuum processing techniques used in state-of-the-art OLEDs are demonstrated employing liquid-crystalline host matrix in the emission layer. Publisher PDF

This work was supported by the UK Engineering and Physical Sciences Research Council under grant EP/J01771X/1, A European Union FAMOS project (FP7 ICT, 317744), and the ’BRAINS’ 600th anniversary appeal, and Dr. E. Killick. We would also like to thank The RS Macdonald Charitable Trust for funding support. KD acknowledges support of a Royal Society Leverhulme Trust Senior Fellowship. This work was also supported by the PreDiCT-TB consortium [IMI Joint undertaking grant agreement number 115337, resources of which are composed of financial contribution from the European Union’s Seventh Framework Programme (FP7/2007-2013) and EFPIA companies’ in kind contribution (www.imi.europa.eu)] The ability to identify and characterise individual cells of the immune system under label-free conditions would be a significant advantage in biomedical and clinical studies where untouched and unmodified cells are required. We present a multi-modal system capable of simultaneously acquiring both single point Raman spectra and digital holographic images of single cells. We use this combined approach to identify and discriminate between immune cell populations CD4+ T cells, B cells and monocytes. We investigate several approaches to interpret the phase images including signal intensity histograms and texture analysis. Both modalities are independently able to discriminate between cell subsets and dual-modality may therefore be used a means for validation. We demonstrate here sensitivities achieved in the range of 86.8% to 100%, and specificities in the range of 85.4% to 100%. Additionally each modality provides information not available from the other providing both a molecular and a morphological signature of each cell. Publisher PDF

We acknowledge support from the ERC Starting Grant ABLASE (640012), the Scottish Funding Council (via SUPA), and the European Union Marie Curie Career Integration Grant (PCIG12-GA-2012-334407). MS acknowledges funding by the European Commission through a Marie Sklodowska-Curie Individual Fellowship (659213). MK and PL acknowledge funding from the EPSRC DTG (EP/M506631/1 and EP/L505079/1). Reliable methods to individually track large numbers of cells in real time are urgently needed to advance our understanding of important biological processes like cancer metastasis, neuronal network development and wound healing. It has recently been suggested to introduce microscopic whispering gallery mode lasers into the cytoplasm of cells and to use their characteristic, size dependent emission spectrum as optical barcode but so far there is no evidence that this approach is generally applicable. Here, we describe a method that drastically improves intracellular delivery of resonators for several cell types, including mitotic and non-phagocytic cells. In addition, we characterize the influence of resonator size on the spectral characteristics of the emitted laser light and identify an optimum size range that facilitates tagging and tracking of thousands of cells simultaneously. Finally, we observe that the microresonators remain internalized by cells during cell division, which enables tagging several generations of cells. Publisher PDF

The authors thank the UK Engineering and Physical Sciences Research Council (grant EP/J01771/X) and the European Union project FAMOS (FP7 ICT, contract no. 317744) for funding. P.P. acknowledges funding by the Estonian Research Council (grants PUTJD8 and PUT369). We demonstrate the first light sheet microscope using propagation invariant, accelerating Airy beams that operates both in single- and two-photon modes. The use of the Airy beam permits us to develop an ultra compact, high resolution light sheet system without beam scanning. In two-photon mode, an increase in the field of view over the use of a standard Gaussian beam by a factor of six is demonstrated. This implementation for light sheet microscopy opens up new possibilities across a wide range of biomedical applications, especially for the study of neuronal processes. Publisher PDF

The maintenance of genome stability is an essential cellular process to prevent the development of diseases including cancer. hSSB1 (NABP2/ OBFC2A) is a critical component of the DNA damage response where it participates in the repair of double-strand DNA breaks and in base excision repair of oxidized guanine residues (8-oxoguanine) by aiding the localization of the human 8-oxoguanine glycosylase (hOGG1) to damaged DNA. Here we demonstrate that following oxidative stress, hSSB1 is stabilized as an oligomer which is required for hSSB1 to function in the removal of 8-oxoguanine. Monomeric hSSB1 shows a decreased affinity for oxidized DNA resulting in a cellular 8-oxoguanine-repair defect and in the absence of ATM signaling initiation. While hSSB1 oligomerization is important for the removal of 8-oxoguanine from the genome, it is not required for the repair of double-strand DNA-breaks by homologous recombination. These findings demonstrate a novel hSSB1 regulatory mechanism for the repair of damaged DNA.

Light-sheet fluorescence microscopy has emerged as a powerful platform for 3-D volumetric imaging in the life sciences. Here, we introduce an important step towards its use deep inside biological tissue. Our new technique, based on digital holography, enables delivery of the light-sheet through a multimode optical fibre – an optical element with extremely small footprint, yet permitting complex control of light transport processes within. We show that this approach supports some of the most advanced methods in light-sheet microscopy: by taking advantage of the cylindrical symmetry of the fibre, we facilitate the wavefront engineering methods for generation of both Bessel and structured Bessel beam plane illumination. Finally, we assess the quality of imaging on a sample of fluorescent beads fixed in agarose gel and we conclude with a proof-of-principle imaging of a biological sample, namely the regenerating operculum prongs of Spirobranchus lamarcki. Light-sheet fluorescenční mikroskopie se ukázala jako výkonná platforma pro 3-D objemové zobrazování v živých vědách. Zde jsme představili důležitý krok k jeho použití hluboko uvnitř biologické tkáně. Naše nová technika, založená na digitální holografii, umožní propagaci světelného paprsku přes multimodální optické vlákno - optický prvek s extrémně malými rozměry, přesto umožňující komplexní řízení světla transportních procesů uvnitř.

This work is supported by the UK Engineering Physical Sciences Research Council (EPSRC). A prevailing problem in neuroscience is the fast and targeted delivery of DNA into selected neurons. The development of an appropriate methodology would enable the transfection of multiple genes into the same cell or different genes into different neighboring cells as well as rapid cell selective functionalization of neurons. Here, we show that optimized femtosecond optical transfection fulfills these requirements. We also demonstrate successful optical transfection of channelrhodopsin-2 in single selected neurons. We extend the functionality of this technique for wider uptake by neuroscientists by using fast three-dimensional laser beam steering enabling an image-guided “point-and-transfect” user-friendly transfection of selected cells. A sub-second transfection timescale per cell makes this method more rapid by at least two orders of magnitude when compared to alternative single-cell transfection techniques. This novel technology provides the ability to carry out large-scale cell selective genetic studies on neuronal ensembles and perform rapid genetic programming of neural circuits. Publisher PDF

This work was funded by the EPSRC. The modal characterization of various families of beams is a topic of current interest. We recently reported a new method for the simultaneous determination of both the azimuthal and radial mode indices for light fields possessing orbital angular momentum. The method is based upon probing the far-field diffraction pattern from a random aperture and using the recorded data as a 'training set'. We then transform the observed data into uncorrelated variables using the principal component analysis (PCA) algorithm. Here, we show the generic nature of this approach for the simultaneous determination of the modal parameters of Hermite-Gaussian and Bessel beams. This reinforces the widespread applicability of this method for applications including information processing, spectroscopy and manipulation. Additionally, preliminary results demonstrate reliable decomposition of superpositions of Laguerre-Gaussians, yielding the intensities and relative phases of each constituent mode. Thus, this approach represents a powerful method for characterizing the optical multi-dimensional Hilbert space. Publisher PDF

Funding: This project was supported by BBSRC Grant BB/S003223/1 (EV, JG), Royal Society Grant UF150663 (SP), Novo Nordisk Foundation Grant NNF14CC0001 (LJJ), ERC Horizon 2020 Grant Agreement 833504 SPANUMBRA, PRIN 2017 and ERC-SH4-A (2017PSRHPZ) to GV. Left–right asymmetries in the nervous system (lateralisation) influence a broad range of behaviours, from social responses to navigation and language. The role and pathways of endogenous and environmental mechanisms in the ontogeny of lateralisation remains to be established. The domestic chick is a model of both endogenous and experience-induced lateralisation driven by light exposure. Following the endogenous rightward rotation of the embryo, the asymmetrical position in the egg results in a greater exposure of the right eye to environmental light. To identify the genetic pathways activated by asymmetric light stimulation, and their time course, we exposed embryos to different light regimes: darkness, 6 h of light and 24 h of light. We used RNA-seq to compare gene expression in the right and left retinas and telencephalon. We detected differential gene expression in right vs left retina after 6 h of light exposure. This difference was absent in the darkness condition and had already disappeared by 24 h of light exposure, suggesting that light-induced activation is a self-terminating phenomenon. This transient effect of light exposure was associated with a downregulation of the sensitive-period mediator gene DIO2 (iodothyronine deiodinase 2) in the right retina. No differences between genes expressed in the right vs. left telencephalon were detected. Gene networks associated with lateralisation were connected to vascularisation, cell motility, and the extracellular matrix. Interestingly, we know that the extracellular matrix—including the differentially expressed PDGFRB gene—is involved in morphogenesis, sensitive periods, and in the endogenous chiral mechanism of primary cilia, that drives lateralisation. Our data show a similarity between endogenous and experience-driven lateralisation, identifying functional gene networks that affect lateralisation in a specific time window. Publisher PDF