195 research outputs found

    Can large language models democratize access to dual-use biotechnology?

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    Large language models (LLMs) such as those embedded in 'chatbots' are accelerating and democratizing research by providing comprehensible information and expertise from many different fields. However, these models may also confer easy access to dual-use technologies capable of inflicting great harm. To evaluate this risk, the 'Safeguarding the Future' course at MIT tasked non-scientist students with investigating whether LLM chatbots could be prompted to assist non-experts in causing a pandemic. In one hour, the chatbots suggested four potential pandemic pathogens, explained how they can be generated from synthetic DNA using reverse genetics, supplied the names of DNA synthesis companies unlikely to screen orders, identified detailed protocols and how to troubleshoot them, and recommended that anyone lacking the skills to perform reverse genetics engage a core facility or contract research organization. Collectively, these results suggest that LLMs will make pandemic-class agents widely accessible as soon as they are credibly identified, even to people with little or no laboratory training. Promising nonproliferation measures include pre-release evaluations of LLMs by third parties, curating training datasets to remove harmful concepts, and verifiably screening all DNA generated by synthesis providers or used by contract research organizations and robotic cloud laboratories to engineer organisms or viruses.Comment: 6 pages, 0 figure

    Multiwavelength study of dark globule DC 314.8–5.1 : point-source identification and diffuse emission characterization

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    We present an analysis of multiwavelength observations of the dark globule DC 314.8–5.1, using data from the Gaia optical, Two Micron All Star Survey near-infrared, and Wide-field Infrared Survey Explorer mid-infrared surveys, dedicated imaging with the Spitzer Space Telescope, and X-ray data obtained with the Swift X-Ray Telescope (XRT). The main goal was to identify possible pre-main-sequence stars (PMSs) and young stellar objects (YSOs) associated with the globule. For this, we studied the infrared colors of all point sources within the boundaries of the cloud. After removing sources with nonstellar spectra, we investigated the Gaia parallaxes for the YSO candidates and found that none are physically related to DC 314.8–5.1. In addition, we searched for X-ray emission from PMSs with Swift-XRT, and found no 0.5–10 keV emission down to a luminosity level â‰Č\lesssim 1031^{31} erg s−1^{-1}, typical of a PMS with mass ≄\geq 2 M⹀_{\bigodot}. Our detailed inspection therefore supports a very young, "prestellar core" evolutionary stage for the cloud. Based on archival Planck and IRAS data, we moreover identify the presence of hot dust, with temperatures ≳\gtrsim 100K, in addition to the dominant dust component at 14 K, originating with the associated reflection nebula

    Neuroplastic Changes Following Social Cognition Training in Schizophrenia: A Systematic Review

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    Social cognitive impairment is a key feature of schizophrenia and social cognition training (SCT) is a promising tool to address these deficits. Neurobiological dysfunction in schizophrenia has been widely researched, but neuronal changes induced by SCT have been scarcely explored. This review aims to assess the neuroplastic effects of SCT in patients with schizophrenia spectrum disorders. PubMed and Web of Science databases were searched for clinical trials testing the effects of SCT in functional and structural brain measurements of adult patients with schizophrenia or schizoaffective disorders. A total of 11 studies were included: five used fMRI, two used EEG and ERP, one used ERP only, two used MEG and one study used MRI. Data extracting and processing regarding sociodemographic and clinical variables, intervention characteristics, neuroimaging procedures, neuroplastic findings, effect sizes and study quality criteria was completed by two raters. Results indicate a wide range of structural and functional changes in numerous regions and circuits of the social brain, including early perceptual areas, the limbic system and prefrontal regions. Despite the small number of trials currently available, evidence suggests that SCT is associated with neuroplastic changes in the social brain and concomitant improvements in social cognitive performance. There is a lack of extensive knowledge about the neural mechanisms that underlie social cognitive enhancement after treatment, but the reported findings may shed light on the neural substrates of social cognitive impairment in schizophrenia and how improved treatment procedures can be developed and applied.info:eu-repo/semantics/publishedVersio

    Cryopreservation of swine ovarian tissue : effect of different cryoprotectants on the structural preservation of preantral follicle oocytes

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    The present study aimed to test different cryoprotectants on cryopreservation of pig ovarian tissue. Pig ovaries (n = 3) were collected at a local slaughterhouse. From each ovary, ten cortex samples were taken. One was immediately fixed (control) and another placed in short-term tissue incubation (STTI control). The other 8 samples were cryopreserved, in pairs, using 4 different cryoprotectants: dimethyl sulphoxide (Me2SO – 1.5 M), ethylene glycol (EG – 1.5 M), propanediol (PROH – 1.5 M) and glycerol (GLY – 10%), all with 0.4% sucrose. Samples were slow cooled and stored in liquid nitrogen for 7 days. After thawing and cryoprotectant removal, one sample from each treatment was immediately fixed and the other was placed in short-term tissue incubation (STTI) for 2 h and then fixed. Samples were processed for histology and transmission electron microscopy. The percentages of morphologically normal follicles (MNF) in cryopreserved tissue using Me2SO (67.0 ± 4.9), EG (81.8 ± 1.4) and PROH (55.9 ± 9.9) were significantly lower (P < 0.05) than observed in fresh control tissue (97.7 ± 1.2). When ovarian tissue was cryopreserved with GLY, no morphologically normal follicles could be found (0%). After STTI, PROH showed a significantly lower percentage of MNF when compared with all other treatments and the control. After ultrastructural analysis, follicles cryopreserved with Me2SO and EG showed some small alterations, but no signs of advanced degeneration. Overall, these were similar to follicles from the control group. In conclusion, it is possible to cryopreserve preantral follicles from pig ovarian tissue using Me2SO or EG

    Glucocerebrosidase gene therapy prevents α-synucleinopathy of midbrain dopamine neurons

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    AbstractDiminished lysosomal function can lead to abnormal cellular accumulation of specific proteins, including α-synuclein, contributing to disease pathogenesis of vulnerable neurons in Parkinson's disease (PD) and related α-synucleinopathies. GBA1 encodes for the lysosomal hydrolase glucocerebrosidase (GCase), and mutations in GBA1 are a prominent genetic risk factor for PD. Previous studies showed that in sporadic PD, and in normal aging, GCase brain activity is reduced and levels of corresponding glycolipid substrates are increased. The present study tested whether increasing GCase through AAV-GBA1 intra-cerebral gene delivery in two PD rodent models would reduce the accumulation of α-synuclein and protect midbrain dopamine neurons from α-synuclein-mediated neuronal damage. In the first model, transgenic mice overexpressing wildtype α-synuclein throughout the brain (ASO mice) were used, and in the second model, a rat model of selective dopamine neuron degeneration was induced by AAV-A53T mutant α-synuclein. In ASO mice, intra-cerebral AAV-GBA1 injections into several brain regions increased GCase activity and reduced the accumulation of α-synuclein in the substantia nigra and striatum. In rats, co-injection of AAV-GBA1 with AAV-A53T α-synuclein into the substantia nigra prevented α-synuclein-mediated degeneration of nigrostriatal dopamine neurons by 6months. These neuroprotective effects were associated with altered protein expression of markers of autophagy. These experiments demonstrate, for the first time, the neuroprotective effects of increasing GCase against dopaminergic neuron degeneration, and support the development of therapeutics targeting GCase or other lysosomal genes to improve neuronal handling of α-synuclein

    Pacifier Stiffness Alters the Dynamics of the Suck Central Pattern Generator

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    Variation in pacifier stiffness on non-nutritive suck (NNS) dynamics was examined among infants born prematurely with a history of respiratory distress syndrome. Three types of silicone pacifiers used in the NICU were tested for stiffness, revealing the Super Soothieℱ nipple is 7 times stiffer than the Weeℱ or Soothieℱ pacifiers even though shape and displaced volume are identical. Suck dynamics among 20 preterm infants were subsequently sampled using the Soothieℱ and Super Soothieℱ pacifiers during follow-up at approximately 3 months of age. ANOVA revealed significant differences in NNS cycles/min, NNS amplitude, NNS cycles/burst, and NNS cycle periods as a function of pacifier stiffness. Infants modify the spatiotemporal output of their suck central pattern generator when presented with pacifiers with significantly different mechanical properties. Infants show a non-preference to suck due to high stiffness in the selected pacifier. Therefore, excessive pacifier stiffness may decrease ororhythmic patterning and impact feeding outcomes

    Combining RNAscope and immunohistochemistry to visualize inflammatory gene products in neurons and microglia

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    A challenge for central nervous system (CNS) tissue analysis in neuroscience research has been the difficulty to codetect and colocalize gene and protein expression in the same tissue. Given the importance of identifying gene expression relative to proteins of interest, for example, cell-type specific markers, we aimed to develop a protocol to optimize their codetection. RNAscope fluorescent in situ hybridization (FISH) combined with immunohistochemistry (IHC) in fixed (CNS) tissue sections allows for reliable quantification of gene transcripts of interest within IHC-labeled cells. This paper describes a new method for simultaneous visualization of FISH and IHC in thicker (14-ÎŒm), fixed tissue samples, using spinal cord sections. This method’s effectiveness is shown by the cell-type-specific quantification of two genes, namely the proinflammatory cytokine interleukin-1beta (IL-1b) and the inflammasome NLR family pyrin domain containing 3 (NLRP3). These genes are challenging to measure accurately using immunohistochemistry (IHC) due to the nonspecificity of available antibodies and the hard-to-distinguish, dot-like visualizations of the labeled proteins within the tissue. These measurements were carried out in spinal cord sections after unilateral chronic constriction injury of the sciatic nerve to induce neuroinflammation in the spinal cord. RNAscope is used to label transcripts of genes of interest and IHC is used to label cell-type specific antigens (IBA1 for microglia, NeuN for neurons). This combination allowed for labeled RNA transcripts to be quantified within cell-type specific boundaries using confocal microscopy and standard image analysis methods. This method makes it easy to answer empirical questions that are intractable with standard IHC or in situ hybridization alone. The method, which has been optimized for spinal cord tissue and to minimize tissue preparation time and costs, is described in detail from tissue collection to image analysis. Further, the relative expression changes in inflammatory genes NLRP3 and IL-1b in spinal cord microglia vs. neurons of somatotopically relevant laminae are described for the first time

    Needleless connector decontamination for prevention of central venous access device infection: A pilot randomized controlled trial

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    Pilot randomized controlled trial (180 patients) of needleless connector decontamination. Central line-associated bloodstream infection occurred in 2% (1/61) of 70% isopropyl alcohol (IPA) wipe, 2% (1/59) of 70% IPA cap, and zero (0/58) infections in 2% chlorhexidine gluconate in 70% IPA wipe patients. Larger definitive trials are feasible and needed
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