scholarly journals A new Defective Helper RNA to produce recombinant Sindbis virus that infects neurons but does not propagate

2015 ◽  
Author(s):  
Justus M Kebschull ◽  
Pedro Garcia da Silva ◽  
Anthony M Zador

AbstractRecombinant Sindbis viruses are important tools in neuroscience because they combine rapid and high transgene expression with a capacity to carry large transgenes. Currently, two packaging systems based on the DH(26S)5’SIN and the DH-BB(tRNA;TE12) Defective Helper (DH) RNAs are available for making recombinant Sindbis virus that is neurotropic (able to infect neurons and potentially other cells). Both systems produce a fraction of viral particles that can propagate beyond the primary infected neuron. When injected into mouse brains, viruses produced using these DH RNAs label neurons at the injection site, but also elsewhere in the brain. Such ectopic labeling caused recombinant Sindbis viruses to be classified as anterograde viruses with limited retrograde spread, and can complicate the interpretation of neuroanatomical and other experiments.Here we describe a new DH RNA, DH-BB(5’SIN;TE12ORF), that can be used to produce virus that is both neurotropic and propagation-incompetent. We show in mice that DH-BB(5’SIN;TE12ORF)- packaged virus eliminates infection of cells outside the injection site. We also provide evidence that ectopically labeled cells observed in previous experiments with recombinant Sindbis virus resulted from secondary infection by propagation-competent virus, rather than from inefficient retrograde spread.Virus produced with our new packaging system retains all the advantages of previous recombinant Sindbis viruses, but minimizes the risks of confounding results with unwanted ectopic labeling. It should therefore be considered in future studies in which a neurotropic, recombinant Sindbis virus is needed.


2018 ◽  
Vol 15 (8) ◽  
pp. 743-750 ◽  
Author(s):  
Kresimir Ukalovic ◽  
Sijia Cao ◽  
Sieun Lee ◽  
Qiaoyue Tang ◽  
Mirza Faisal Beg ◽  
...  

Background: Recent work on Alzheimer's disease (AD) diagnosis focuses on neuroimaging modalities; however, these methods are expensive, invasive, and not available to all patients. Ocular imaging of biomarkers, such as drusen in the peripheral retina, could provide an alternative method to diagnose AD. Objective: This study compares macular and peripheral drusen load in control and AD eyes. Methods: Postmortem eye tissues were obtained from donors with a neuropathological diagnosis of AD. Retina from normal donors were processed and categorized into younger (<55 years) and older (>55 years) groups. After fixation and dissection, 3-6 mm punches of RPE/choroid were taken in macular and peripheral (temporal, superior, and inferior) retinal regions. Oil red O positive drusen were counted and grouped into two size categories: small (<63 μm) and intermediate (63-125 μm). Results: There was a significant increase in the total number of macular and peripheral hard drusen in older, compared to younger, normal eyes (p<0.05). Intermediate hard drusen were more commonly found in the temporal region of AD eyes compared to older normal eyes, even after controlling for age (p<0.05). Among the brain and eye tissues from AD donors, there was a significant relationship between cerebral amyloid angiopathy (CAA) severity and number of temporal intermediate hard drusen (r=0.78, p<0.05). Conclusion: Imaging temporal drusen in the eye may have benefit for diagnosing and monitoring progression of AD. Our results on CAA severity and temporal intermediate drusen in the AD eye are novel. Future studies are needed to further understand the interactions among CAA and drusen formation.



2020 ◽  
Vol 4 (11) ◽  
Author(s):  
Katherine M Ranard ◽  
Matthew J Kuchan ◽  
John W Erdman

ABSTRACT Studying vitamin E [α-tocopherol (α-T)] metabolism and function in the brain and other tissues requires an animal model with low α-T status, such as the transgenic α-T transfer protein (Ttpa)–null (Ttpa−/−) mouse model. Ttpa+/− dams can be used to produce Ttpa−/− and Ttpa+/+mice for these studies. However, the α-T content in Ttpa+/− dams’ diet requires optimization; diets must provide sufficient α-T for reproduction, while minimizing the transfer of α-T to the offspring destined for future studies that require low baseline α-T status. The goal of this work was to assess the effectiveness and feasibility of 2 breeding diet strategies on reproduction outcomes and offspring brain α-T concentrations. These findings will help standardize the breeding methodology used to generate the Ttpa−/− mice for neurological studies.



2005 ◽  
Vol 16 (6) ◽  
pp. 741-751 ◽  
Author(s):  
Evelyn Abordo-Adesida ◽  
Antonia Follenzi ◽  
Carlos Barcia ◽  
Sandra Sciascia ◽  
Maria G. Castro ◽  
...  


2015 ◽  
Vol 22 (1) ◽  
pp. 112-116
Author(s):  
Amit Agrawal ◽  
Vissa Shanthi ◽  
Baddukonda Appala Ramakrishna ◽  
Kuppili Venkata Murali Mohan

Abstract First characterized by Stroebe, the gliosarcomas are highly malignant and rare primary tumor of the brain composed of neoplastic glial cells in association with spindle cell sarcomatous elements (biphasic tissue patterns). In spite of being recognized as two different pathologies studies have not shown any significant differences between gliosarcoma and glioblastoma with regard to age, sex, size, clinical presentation, and median survival. In summary, gliosarcoma is an aggressive tumor with a propensity to recur and re-grow with poor outcome. Future studies are needed to understand the true pathology of these biphasic tumors.



1924 ◽  
Vol 39 (4) ◽  
pp. 533-542 ◽  
Author(s):  
James E. McCartney

These studies fail to confirm the statements previously made that microorganisms of the class of the globoid bodies of poliomyelitis may be cultivated in the Smith-Noguchi medium from the so called virus of encephalitis lethargica. They show equally that the herpes virus does not multiply in this medium. The experiments indicate, moreover, that the medium is unfavorable to the survival of the virus, while ordinary broth under aerobic conditions is more favorable for maintaining the activity of both the encephalitic and the herpes viruses. Probably no multiplication of either takes place in the latter medium but merely a survival, and for a maximum period of 6 days in the broth itself, and 12 days in the fragment of brain tissue immersed in the broth. Finally, it has been shown that with a suitable technique the viruses can be passed from the brain of one rabbit to that of another through a long series without contamination with cocci or other common bacterial forms. Hence we regard all reports of the finding of ordinary bacteria in the brain of cases of epidemic or lethargic encephalitis as instances of mixed or secondary infection arising during life, or examples of postmortem invasion of the body, or of faulty technique at the autopsy.



1995 ◽  
Vol 269 (4) ◽  
pp. F564-F570 ◽  
Author(s):  
S. Blau ◽  
L. Daly ◽  
A. Fienberg ◽  
G. Teitelman ◽  
M. E. Ehrlich

DARPP-32, a dopamine- and adenosine 3',5'-cyclic monophosphate (cAMP)-regulated inhibitor of protein phosphatase-1, is highly colocalized with neuronal and nonneuronal D1-type receptors. DARPP-32 concentration is enriched in the renal outer medulla and in the medium-size spiny neurons of the brain. In the ascending limb of the loop of Henle, DARPP-32 is phosphorylated following stimulation by dopamine and other first messengers, and in this form inhibits the activity of the Na(+)-K(+)-adenosinetriphosphatase pump. For functional analysis of the DARPP-32 promoter in the kidney, we characterized the murine gene. There are two groups of transcription start sites utilized in the brain, but the proximal set appears to be preferentially used in the kidney. In four of four lines of mice carrying a DARPP-32/lacZ transgene with 2.1 kb of 5'-flanking DNA, adult kidney lacZ transgene expression mimicked that of endogenous DARPP-32. There was no ectopic expression in peripheral organs. We conclude that the sequences necessary for direction of DARPP-32 expression to the medullary thick ascending limb are contained within this 2.1-kb fragment.



2022 ◽  
Vol 23 (2) ◽  
pp. 846
Author(s):  
Stanislas Martin ◽  
Audrey Foulon ◽  
Wissam El Hage ◽  
Diane Dufour-Rainfray ◽  
Frédéric Denis

The study aimed to examine the impact of the oropharyngeal microbiome in the pathophysiology of schizophrenia and to clarify whether there might be a bidirectional link between the oral microbiota and the brain in a context of dysbiosis-related neuroinflammation. We selected nine articles including three systemic reviews with several articles from the same research team. Different themes emerged, which we grouped into 5 distinct parts concerning the oropharyngeal phageome, the oropharyngeal microbiome, the salivary microbiome and periodontal disease potentially associated with schizophrenia, and the impact of drugs on the microbiome and schizophrenia. We pointed out the presence of phageoma in patients suffering from schizophrenia and that periodontal disease reinforces the role of inflammation in the pathophysiology of schizophrenia. Moreover, saliva could be an interesting substrate to characterize the different stages of schizophrenia. However, the few studies we have on the subject are limited in scope, and some of them are the work of a single team. At this stage of knowledge, it is difficult to conclude on the existence of a bidirectional link between the brain and the oral microbiome. Future studies on the subject will clarify these questions that for the moment remain unresolved.



Development ◽  
2000 ◽  
Vol 127 (20) ◽  
pp. 4455-4467 ◽  
Author(s):  
J. Hadchouel ◽  
S. Tajbakhsh ◽  
M. Primig ◽  
T.H. Chang ◽  
P. Daubas ◽  
...  

The myogenic factor Myf5 plays a key role in muscle cell determination, in response to signalling cascades that lead to the specification of muscle progenitor cells. We have adopted a YAC transgenic approach to identify regulatory sequences that direct the complex spatiotemporal expression of this gene during myogenesis in the mouse embryo. Important regulatory regions with distinct properties are distributed over 96 kb upstream of the Myf5 gene. The proximal 23 kb region directs early expression in the branchial arches, epaxial dermomyotome and in a central part of the myotome, the epaxial intercalated domain. Robust expression at most sites in the embryo where skeletal muscle forms depends on an enhancer-like sequence located between −58 and −48 kb from the Myf5 gene. This element is active in the epaxial and hypaxial myotome, in limb muscles, in the hypoglossal chord and also at the sites of Myf5 transcription in prosomeres p1 and p4 of the brain. However later expression of Myf5 depends on a more distal region between −96 and −63 kb, which does not behave as an enhancer. This element is necessary for expression in head muscles but strikingly only plays a role in a subset of trunk muscles, notably the hypaxially derived ventral body muscles and also those of the diaphragm and tongue. Transgene expression in limb muscle masses is not affected by removal of the −96/-63 region. Epaxially derived muscles and some hypaxial muscles, such as the intercostals and those of the limb girdles, are also unaffected. This region therefore reveals unexpected heterogeneity between muscle masses, which may be related to different facets of myogenesis at these sites. Such regulatory heterogeneity may underlie the observed restriction of myopathies to particular muscle subgroups.



2001 ◽  
Vol 1 ◽  
pp. 555-556 ◽  
Author(s):  
Markus Glatzel

Transmissible spongiform encephalopathies are a group of invariably fatal neurodegenerative diseases. The infectious agent is termed prion and is thought to be composed of a modified protein (PrPSc or PrPRES), a protease-resistant conformer of the normal host-encoded membrane glycoprotein, PrPC[1]. Bovine spongiform encephalopathy, scrapie of sheep, and Creutzfeldt-Jakob disease are among the most notable transmissible spongiform encephalopathies. Prions are most efficiently propagated trough intracerebral inoculation, yet the entry point of the infectious agent is often through peripheral sites like the gastrointestinal tract[2,3]. The process by which prions invade the brain is termed neuroinvasion[4]. We and others have speculated that, depending on the amount of infectious agent injected, the injection site, and the strain of prions employed, neuroinvasion can occur either directly via peripheral nerves or first through the lymphoreticular system and then via peripheral nerves[5].



GigaScience ◽  
2020 ◽  
Vol 9 (7) ◽  
Author(s):  
Bruce A Rosa ◽  
Young-Jun Choi ◽  
Samantha N McNulty ◽  
Hyeim Jung ◽  
John Martin ◽  
...  

Abstract Background Paragonimus spp. (lung flukes) are among the most injurious foodborne helminths, infecting ∼23 million people and subjecting ∼292 million to infection risk. Paragonimiasis is acquired from infected undercooked crustaceans and primarily affects the lungs but often causes lesions elsewhere including the brain. The disease is easily mistaken for tuberculosis owing to similar pulmonary symptoms, and accordingly, diagnostics are in demand. Results We assembled, annotated, and compared draft genomes of 4 prevalent and distinct Paragonimus species: Paragonimus miyazakii, Paragonimus westermani, Paragonimus kellicotti, and Paragonimus heterotremus. Genomes ranged from 697 to 923 Mb, included 12,072–12,853 genes, and were 71.6–90.1% complete according to BUSCO. Orthologous group analysis spanning 21 species (lung, liver, and blood flukes, additional platyhelminths, and hosts) provided insights into lung fluke biology. We identified 256 lung fluke–specific and conserved orthologous groups with consistent transcriptional adult-stage Paragonimus expression profiles and enriched for iron acquisition, immune modulation, and other parasite functions. Previously identified Paragonimus diagnostic antigens were matched to genes, providing an opportunity to optimize and ensure pan-Paragonimus reactivity for diagnostic assays. Conclusions This report provides advances in molecular understanding of Paragonimus and underpins future studies into the biology, evolution, and pathogenesis of Paragonimus and related foodborne flukes. We anticipate that these novel genomic and transcriptomic resources will be invaluable for future lung fluke research.



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