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91.
Cynthia M. Solek Nasr A.I. Farooqi Niklas Brake Philip Kesner Anne Schohl Jack P. Antel Edward S. Ruthazer 《The Journal of neuroscience》2021,41(29):6353
Neuroimmune interaction during development is strongly implicated in the pathogenesis of neurodevelopmental disorders, but the mechanisms that cause neuronal circuit dysregulation are not well understood. We performed in vivo imaging of the developing retinotectal system in the larval zebrafish to characterize the effects of immune system activation on refinement of an archetypal sensory processing circuit. Acute inflammatory insult induced hyperdynamic remodeling of developing retinal axons in larval fish and increased axon arbor elaboration over days. Using calcium imaging in GCaMP6s transgenic fish, we showed that these morphologic changes were accompanied by a shift toward decreased visual acuity in tectal cells. This finding was supported by poorer performance in a visually guided behavioral task. We further found that the pro-inflammatory cytokine, interleukin-1β (IL-1β), is upregulated by the inflammatory insult, and that downregulation of IL-1β abrogated the effects of inflammation on axonal dynamics and growth. Moreover, baseline branching of the retinal ganglion cell arbors in IL-1β morphant animals was significantly different from that in control larvae, and their performance in a predation assay was impaired, indicating a role for this cytokine in normal neuronal development. This work establishes a simple and powerful non-mammalian model of developmental immune activation and demonstrates a role for IL-1β in mediating the pathologic effects of inflammation on neuronal circuit development.SIGNIFICANCE STATEMENT Maternal immune activation can increase the risk of neurodevelopmental disorders in offspring; however, the mechanisms involved are not fully understood. Using a non-mammalian vertebrate model of developmental immune activation, we show that even brief activation of inflammatory pathways has immediate and long-term effects on the arborization of axons, and that these morphologic changes have functional and behavioral consequences. Finally, we show that the pro-inflammatory cytokine IL-1β plays an essential role in both the effects of inflammation on circuit formation and normal axonal development. Our data add to a growing body of evidence supporting epidemiological studies linking immune activation to neurodevelopmental disorders, and help shed light on the molecular and cellular processes that contribute to the etiology of these disorders. 相似文献
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Sze DY Hwang GL Kao JS Frisoli JK Kee ST Razavi MK Ahmed A 《Journal of vascular and interventional radiology : JVIR》2008,19(11):1653-1658
Excessive shunting through transjugular intrahepatic portosystemic shunts (TIPS) can cause life-threatening hepatic encephalopathy and insufficiency. Intentional reduction of flow may be effective but difficult to control. The present report describes refinements of the parallel stent/stent-graft technique of flow reduction that is adjustable in either direction. Six patients underwent TIPS reduction with varying stent positioning and a variety of commercial products. Flow was adjusted by iterative balloon dilatation of the stent and stent-graft, resulting in a mean gradient increase of 8 mm Hg. All cases were technically successful, but 1-year survival was seen in only the patient who underwent liver transplantation. 相似文献
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Z J Shao M I Farooqi S Diaz A K Krishna N A Muhammad 《Pharmaceutical development and technology》2001,6(2):247-254
A new commercially available sustained-release matrix material, Kollidon SR, composed of polyvinylacetate and povidone, was evaluated with respect to its ability to modulate the in vitro release of a highly water-soluble model compound, diphenhydramine HCl. Kollidon SR was found to provide a sustained-release effect for the model compound, with certain formulation and processing variables playing an important role in controlling its release kinetics. Formulation variables affecting the release include the level of the polymeric material in the matrix, excipient level, as well as the nature of the excipients (water soluble vs. water insoluble). Increasing the ratio of a water-insoluble excipient, Emcompress, to Kollidon SR enhanced drug release. The incorporation of a water-soluble excipient, lactose, accelerated its release rate in a more pronounced manner. Stability studies conducted at 40 degrees C/75% RH revealed a slow-down in dissolution rate for the drug-Kollidon SR formulation, as a result of polyvinylacetate relaxation. Further studies demonstrated that a post-compression curing step effectively stabilized the release pattern of formulations containing > or = 47% Kollidon SR. The release mechanism of Kollidon-drug and drug-Kollidon-Emcompress formulations appears to be diffusion controlled, while that of the drug-Kollidon-lactose formulation appears to be controlled predominantly by diffusion along with erosion. 相似文献
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Randomised controlled trial of reminders to enhance the impact of audit in general practice on management of patients who use benzodiazepines. 下载免费PDF全文
OBJECTIVE: To determine whether reminder cards in medical records enhance the effectiveness of audit with feedback in improving the care of patients taking long term benzodiazepine drugs. DESIGN: Randomised trial, practices receiving feedback only in one group and practices receiving feedback plus reminder cards in the other group. SETTING: 18 general practices in Leicestershire. SUBJECTS: Random samples of patients who had been taking a benzodiazepine anxiolytic or hypnotic drug for four weeks or longer. MAIN OUTCOME MEASURES: Entries in medical records indicating compliance with five criteria of care: assessment of suitability for withdrawal; being told about dependency; withdrawal being recommended; withdrawal or continuing medication; and a consultation with the general practitioner in the past year. Data were collected before and after feedback or feedback plus reminders. RESULTS: Of a total population of 125,846 registered with the 18 practices, 2409 (1.9%) had been taking a benzodiazepine for four weeks or longer. Of the 742 in the first samples, 543 (73.2%) were women, the mean (SD) age was 68.7 (14.9) years, and they had been taking a benzodiazepine for 10.1 (6.7) years. The number of patients whose care complied with the criteria rose after the interventions to implement change. The increase was greater in practices receiving feedback plus reminders for only two of the five criteria "told about dependency" increasing from 52 (11.1%) to 118 (25.8%) in the feedback only group, and from 27 (10.5%) to 184 (43.0%) in the feedback plus reminders group; odds ratio (OR) 1.46 (95% confidence interval (95% CI) 1.32 to 5.21); and "consulted in the past year" increasing from 434 (93.1%) to 411 (95.8%) in the feedback only group and 255 (96.6%) to 400 (99.8%) in the feedback plus reminders group, OR (95% CI) 13.5 (2.01 to 330.3). CONCLUSIONS: Reminder cards had only a limited effect and cannot be recommended for routine use. There were improvements in the care of patients of both groups of practices and further studies are indicated to determine the impact of both systematically developed criteria and reminders embedded into restructured medical records. 相似文献
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Surasak Jittavisutthikul Jeeraphong Thanongsaksrikul Kanyarat Thueng-in Monrat Chulanetra Potjanee Srimanote Watee Seesuay Aijaz Ahmad Malik Wanpen Chaicumpa 《Viruses》2015,7(4):2030-2056
There is a need for safe and broadly effective anti-HCV agents that can cope with genetic multiplicity and mutations of the virus. In this study, humanized-camel VHHs to genotype 3a HCV serine protease were produced and were linked molecularly to a cell penetrating peptide, penetratin (PEN). Human hepatic (Huh7) cells transfected with the JFH-1 RNA of HCV genotype 2a and treated with the cell penetrable nanobodies (transbodies) had a marked reduction of the HCV RNA intracellularly and in their culture fluids, less HCV foci inside the cells and less amounts of HCV core antigen in culture supernatants compared with the infected cells cultured in the medium alone. The PEN-VHH-treated-transfected cells also had up-regulation of the genes coding for the host innate immune response (TRIF, TRAF3, IRF3, IL-28B and IFN-β), indicating that the cell penetrable nanobodies rescued the host innate immune response from the HCV mediated-suppression. Computerized intermolecular docking revealed that the VHHs bound to residues of the protease catalytic triad, oxyanion loop and/or the NS3 N-terminal portion important for non-covalent binding of the NS4A protease cofactor protein. The so-produced transbodies have high potential for testing further as a candidate for safe, broadly effective and virus mutation tolerable anti-HCV agents. 相似文献
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