Equiluminant stimuli help assess the integrity of colour perception and the relationship of colou... more Equiluminant stimuli help assess the integrity of colour perception and the relationship of colour to other visual features. As a result of individual variation, it is necessary to calibrate experimental visual stimuli to suit each individual’s unique equiluminant ratio. Most traditional methods rely on training observers to report their subjective equiluminance point. Such paradigms cannot easily be implemented on pre-verbal or non-verbal observers. One alternative, optokinetic nystagmus (OKN) of the eye in response to motion, is partially compromised by recent observations that changes in attentional fixation affect the OKN. Here, we present a novel Pupil Frequency-Tagging Method (PFTM) for detecting a participant’s unique equiluminance point without verbal instruction and with minimal training. PFTM analyses reflexive pupil oscillations induced by slow (< 2 Hz) temporal alternations between coloured stimuli. Two equiluminant stimuli will induce a similar pupil dilation respons...
PURPOSE: Recombinant adeno-associated viruses (AAV) are widely used vectors for gene transfer int... more PURPOSE: Recombinant adeno-associated viruses (AAV) are widely used vectors for gene transfer into the central nervous system (CNS).However, Low transduction efficiency andthe delay in transgene expression have hampered it from wide application in such as early embryonic development and the brain of higher mammals for both basic and clinic researches. This study is designed to establish a new means to improve both the efficiency and timing of AAV transduction in transgene expression.&nbsp;&nbsp; METHODS: By co-administration of doxorubicin with AAV8 vector into the cortex of cat, we firstly evaluated the effect of doxorubicin on enhancing vector transfection and transgene expression at different time points after infection. Then, we characterized the dose dependence of doxorubicin on AAV-mediated gene expression by varying the concentration of doxorubicin. The toxicity of doxorubicin was also examined by cell apoptosis assay.&nbsp;&nbsp;&nbsp; RESULTS:Local administration of 10 &mu;g/mL doxorubicin remarkably facilitated AAV8-based gene transfer to neurons, increasing both cell numbers and expression level of GFP. The doxorubicin accelerated GFP expression is observed to appear as earlier as the third day after infection, and increased GFP intensity is persistent through the following multiple weeks in time. Doxorubicin was found to increase the neural expression of GFP at doses between 0.1 ~ 10 &mu;g/mL with little toxicity, but induced neuron loss at a dose higher than 30 &mu;g/mL. CONCLUSIONS:Co-infusion of doxorubicin accelerates AAV-based transgene expression in the cortex of higher mammals. This improved efficiency and timing of AAV transduction might have great potentials in the application for early embryonic development and other neurophysiological research for CNS diseases in higher mammals. &nbsp; &nbsp; &nbsp;&nbsp;</p
Summary Rapid and efficient gene transduction via recombinant adeno-associated viruses (rAAVs) is... more Summary Rapid and efficient gene transduction via recombinant adeno-associated viruses (rAAVs) is highly desirable across many basic and clinical research domains. Here, we report that vector co-infusion with doxorubicin, a clinical anti-cancer drug, markedly enhanced rAAV-mediated transgene expression in the cerebral cortex across mammalian species (cat, mouse, and macaque), acting throughout the time period examined and detectable at just three days after transfection. This enhancement showed serotype generality, being common to all rAAV serotypes tested (2, 8, 9, and PHP.eB) and was observed both locally and at remote locations consistent with doxorubicin undergoing retrograde axonal transport. All these effects were observed at doses matching human blood plasma levels in clinical therapy and lacked detectable cytotoxicity as assessed by cell morphology, activity, apoptosis, and behavioral testing. Altogether, this study identifies an effective means to improve the capability and scope of in vivo rAAV applications, amplifying cell transduction at doxorubicin concentrations paralleling medical practice.
Equiluminant stimuli help assess the integrity of colour perception and the relationship of colou... more Equiluminant stimuli help assess the integrity of colour perception and the relationship of colour to other visual features. As a result of individual variation, it is necessary to calibrate experimental visual stimuli to suit each individual’s unique equiluminant ratio. Most traditional methods rely on training observers to report their subjective equiluminance point. Such paradigms cannot easily be implemented on pre-verbal or non-verbal observers. One alternative, optokinetic nystagmus (OKN) of the eye in response to motion, is partially compromised by recent observations that changes in attentional fixation affect the OKN. Here, we present a novel Pupil Frequency-Tagging Method (PFTM) for detecting a participant’s unique equiluminance point without verbal instruction and with minimal training. PFTM analyses reflexive pupil oscillations induced by slow (< 2 Hz) temporal alternations between coloured stimuli. Two equiluminant stimuli will induce a similar pupil dilation respons...
PURPOSE: Recombinant adeno-associated viruses (AAV) are widely used vectors for gene transfer int... more PURPOSE: Recombinant adeno-associated viruses (AAV) are widely used vectors for gene transfer into the central nervous system (CNS).However, Low transduction efficiency andthe delay in transgene expression have hampered it from wide application in such as early embryonic development and the brain of higher mammals for both basic and clinic researches. This study is designed to establish a new means to improve both the efficiency and timing of AAV transduction in transgene expression.&nbsp;&nbsp; METHODS: By co-administration of doxorubicin with AAV8 vector into the cortex of cat, we firstly evaluated the effect of doxorubicin on enhancing vector transfection and transgene expression at different time points after infection. Then, we characterized the dose dependence of doxorubicin on AAV-mediated gene expression by varying the concentration of doxorubicin. The toxicity of doxorubicin was also examined by cell apoptosis assay.&nbsp;&nbsp;&nbsp; RESULTS:Local administration of 10 &mu;g/mL doxorubicin remarkably facilitated AAV8-based gene transfer to neurons, increasing both cell numbers and expression level of GFP. The doxorubicin accelerated GFP expression is observed to appear as earlier as the third day after infection, and increased GFP intensity is persistent through the following multiple weeks in time. Doxorubicin was found to increase the neural expression of GFP at doses between 0.1 ~ 10 &mu;g/mL with little toxicity, but induced neuron loss at a dose higher than 30 &mu;g/mL. CONCLUSIONS:Co-infusion of doxorubicin accelerates AAV-based transgene expression in the cortex of higher mammals. This improved efficiency and timing of AAV transduction might have great potentials in the application for early embryonic development and other neurophysiological research for CNS diseases in higher mammals. &nbsp; &nbsp; &nbsp;&nbsp;</p
Summary Rapid and efficient gene transduction via recombinant adeno-associated viruses (rAAVs) is... more Summary Rapid and efficient gene transduction via recombinant adeno-associated viruses (rAAVs) is highly desirable across many basic and clinical research domains. Here, we report that vector co-infusion with doxorubicin, a clinical anti-cancer drug, markedly enhanced rAAV-mediated transgene expression in the cerebral cortex across mammalian species (cat, mouse, and macaque), acting throughout the time period examined and detectable at just three days after transfection. This enhancement showed serotype generality, being common to all rAAV serotypes tested (2, 8, 9, and PHP.eB) and was observed both locally and at remote locations consistent with doxorubicin undergoing retrograde axonal transport. All these effects were observed at doses matching human blood plasma levels in clinical therapy and lacked detectable cytotoxicity as assessed by cell morphology, activity, apoptosis, and behavioral testing. Altogether, this study identifies an effective means to improve the capability and scope of in vivo rAAV applications, amplifying cell transduction at doxorubicin concentrations paralleling medical practice.
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Papers by Ian M Andolina