DYT1 early-onset generalized torsion dystonia is an inherited movement disorder associated with mutations in DYT1 that codes for torsinA protein. The most common mutation seen in this gene is a trinucleotide deletion of GAG. We previously reported a motor control deficit on a beam-walking task in our Dyt1 ΔGAG knock-in heterozygous mice. In this report we show the reversal of this motor deficit with the anticholinergic trihexyphenidyl (THP), a drug commonly used to treat movement problems in dystonia patients. THP also restored the reduced corticostriatal long-term depression (LTD) observed in these mice. Corticostriatal LTD has long been known to be dependent on D2 receptor activation. In this mouse model, striatal D2 receptors were expressed at lower quantities in comparison to wild-type mice. Furthermore, the mice were also partially resistant to FPL64176, an agonist of L-type calcium channels that have been previously reported to cause severe dystonic-like symptoms in wild-type mice. Our findings collectively suggest that altered communication between cholinergic interneurons and medium spiny neurons is responsible for the LTD deficit and that this synaptic plasticity modification may be involved in the striatal motor control abnormalities in our mouse model of DYT1 dystonia.

Kainic acid (KA) treatment is a well-established model of hippocampal neuron death mediated in large part by KA receptor-induced excitotoxicity. KA-induced, delayed neuron death has been shown previously to follow the induction of seizures and exhibit characteristics of both apoptosis and necrosis. Growing evidence supports a role of autophagic stress-induced death of neurons in several in vitro and in vivo models of neuron death and neurodegeneration. However, whether autophagic stress also plays a role in KA-induced excitotoxicity has not been previously investigated. To examine whether KA alters the levels of proteins associated with or known to regulate the formation of autophagic vacuoles, we isolated hippocampal extracts from control mice and in mice following 2-16h KA injection. KA induced a significant increase in the amount of LC3-II, a specific marker of autophagic vacuoles, at 4-6h following KA, which indicates a transient induction of autophagic stress. Levels of autophagy-associated proteins including ATG5 (conjugated to ATG12), ATG6 and ATG7 did not change significantly after treatment with KA. However, ratios of phospho-mTOR/ mTOR were elevated from 6-16h, and ratios of phospho-Akt/Akt were elevated at 16h following KA treatment, suggesting a potential negative feedback loop to inhibit further stimulation of autophagic stress. Together these data indicate the transient induction of autophagic stress by KA which may serve to regulate excitotoxic death in mouse hippocampus. Keywords kainic acid; hippocampus; autophagy; ATG5; ATG7; Akt; mTOR; LC3The excitatory amino acid neurotransmitter glutamate is known to play an important role in a vast array of neuronal activities as well as in the induction of excitotoxic neurodegeneration through massive activation of its receptors [1;2]. Kainic acid (KA) is a potent glutamate receptor agonist with selectivity towards non-N-methyl-D-aspartate (NMDA)-type glutamate receptors [3;4]. KA is well known for its ability to induce seizures within minutes of its administration and is followed by a delayed excitotoxic neuron death in the hippocampus several hours later, in part through an increase in intracellular calcium and activation of calcium-dependent neuron death pathways [5][6][7]. Both apoptotic and necrotic death of neurons Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Autophagic stress results from alterations in autophagy, a lysosomal degradation pathway that is responsible for the homeostatically regulated turnover of macronutrients and organelles [10]. Macroautophagy, the most prominent form of autophagy ...

This study reported the clonal dissemination of OXA-232-producing sequence type 15 (ST15) carbapenem-resistant Klebsiella pneumoniae among elderly patients in China. All patients were immunocompromised, suffered from multiple underlying diseases, and were hospitalized for a prolonged period; however, they slowly recovered on antimicrobial therapy. The blaOXA-232 gene was in a 6.1-kb ColKP3-type nonconjugative plasmid. The strains displayed a multidrug resistance phenotype and were not hypervirulent despite harboring a virulence plasmid. Active surveillance should be enforced to control further transmission.

SUMMARYMovement disorders represent a significant societal burden for which therapeutic options are limited and focused on treating disease symptomality. Early-onset torsion dystonia (EOTD) is one such disorder characterized by sustained and involuntary muscle contractions that frequently cause repetitive movements or abnormal postures. Transmitted in an autosomal dominant manner with reduced penetrance, EOTD is caused in most cases by the deletion of a glutamic acid (DE) in the DYT1 (also known as TOR1A) gene product, torsinA. Although some patients respond well to anticholingerics, therapy is primarily limited to either neurosurgery or chemodenervation. As mutant torsinA (DE) expression results in decreased torsinA function, therapeutic strategies directed toward enhancement of wild-type (WT) torsinA activity in patients who are heterozygous for mutant DYT1 may restore normal cellular functionality. Here, we report results from the first-ever screen for candidate small molecule therapeutics for EOTD, using multiple activity-based readouts for torsinA function in Caenorhabditis elegans, subsequent validation in human DYT1 patient fibroblasts, and behavioral rescue in a mouse model of DYT1 dystonia. We exploited the nematode to rapidly discern chemical effectors of torsinA and identified two classes of antibiotics, quinolones and aminopenicillins, which enhance WT torsinA activity in two separate in vivo assays. Representative molecules were assayed in EOTD patient fibroblasts for improvements in torsinA-dependent secretory function, which was improved significantly by ampicillin. Furthermore, a behavioral defect associated with an EOTD mouse knock-in model was also rescued following administration of ampicillin. These combined data indicate that specific small molecules that enhance torsinA activity represent a promising new approach toward therapeutic development for EOTD, and potentially for other diseases involving the processing of mutant proteins.

p53 deletion augments neutrophil-mediated bacterial clearance in the lung at the expense of tissue homeostasis, leading to increased mortality.

Neuroblastoma (NB) is the most common extra-cranial solid tumor in childhood with the overall 5 years' survival less than 40%. Polo-like kinase 1 (PLK1) is a serine/threonine-protein kinase expressed during mitosis and over expressed in multiple cancers, including neuroblastoma. We found that higher PLK1 expression related to poor outcome of NB patients. BI2536, a small molecule inhibitor against PLK1, significantly reduced cell viability in a panel of NB cell lines, with IC50 less than 100 nM. PLK1 inhibition by BI 2536 treatment induced cell cycle arrest at G2/M phase and cell apoptosis in NB cells. Realtime PCR array revealed the PLK1 inhibition related genes, such as BIRC7, TNFSF10, LGALS1 and DAD1 et al. Moreover, autophagy activity was investigated in the NB cells treated with BI 2536. BI 2536 treatment in NB cells increased LC3-II puncta formation and LC3-II expression. Formation of autophagosome induced by BI 2536 was observed by transmission electron microscopy. However, BI2536 abrogated the autophagic flux in NB cells by reducing SQSTM1/p62 expression and AMPKα T172 phosphorylation. These results provide new clues for the molecular mechanism of cell death induced by BI 2536 and suggest that BI 2536 may act as new candidate drug for neuroblastoma.

Background Although the emergence of the plasmid-mediated colistin resistance gene, mcr-1, caused global concern, little is known about its clinical implications and transmission characteristics over time. We aimed to investigate the clinical relevance of infection with mcr-1-positive Escherichia coli isolates and to investigate long-term plasmid dynamics. MethodsWe did a multicentre case-control study and molecular epidemiological survey of mcr-1-positive E coli infections. E coli isolates from four hospitals in China in 2008 to 2017 were collected and screened for mcr-1 by PCR and Sanger sequencing. Patients with mcr-1-positive E coli infections and matched controls with mcr-1-negative E coli infections were included in a 1:4 ratio, considering age, sex, living environment, comorbidities, antimicrobials used, and clinical sample type as potential risk factors in a regression model. 28-day mortality was also observed. The genomes of all mcr-1-positive E coli were sequenced to explore their genetic background and map ISApl1 elements. Plasmids carrying mcr-1 were characterised by their resistance profile and incompatibility group. Findings 29 100 isolates were collected across all hospitals and during the study period, 300 (1•03%) of which were mcr-1-positive E coli. The overall proportion of mcr-1-positive isolates significantly increased from 0•42% (1 of 240) in 2008 to 1•39% (66 of 4748; p<0•0001) in 2017. Factors related to health-care contact, including receiving cancer care, indwelling central venous catheter, and hospitalisation in the past 3 months, and some sample types (pus secretion and sputum) were significantly associated with mcr-1-positive E coli infection. 28-day mortality was low in both mcr-1positive (11 [4•4%] of 248 patients) and mcr-1-negative (39 [3•8%] of 1030 patients) groups and did not significantly differ. Although the genetic background of mcr-1-positive E coli was diverse, most of the mcr-1-encoding plasmids occurred in three dominant Inc groups (IncX4, IncI2, and IncHI2). Only the large IncHI2 plasmids conferred multiple resistances and probably integrated with other resistance plasmids. In 205 (68%) of 300 mcr-1-positive E coli isolates, mcr-1 genes lost their capacity for mobilisation because of loss of flanking ISApl1 elements.Interpretation The prevalence of mcr-1-positive E coli infection among patients increased over the study period, although it remained low. Health-care contact was the most probable risk factor. Plasmids are likely to have played a critical role in mcr-1 transmission, rather than clone dissemination and lateral transfer of ISApl1. Our findings underscore the importance of continued surveillance of E coli strains positive for mcr-1 and potentially other resistanceassociated genes, particularly in hospital settings.

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