Postinfectious Autoimmune Syndrome as a Key Factor in Chronization of the Infectious Disease

The Gut Commensal Microbiome of Drosophila melanogaster Is Modified by the Endosymbiont Wolbachia

mSphere ◽

10.1128/msphere.00287-17 ◽

2017 ◽

Vol 2 (5) ◽

Cited By ~ 32

Author(s):

Rama K. Simhadri ◽

Eva M. Fast ◽

Rong Guo ◽

Michaela J. Schultz ◽

Natalie Vaisman ◽

...

Keyword(s):

Infectious Disease ◽

Control Strategies ◽

Large Fraction ◽

Bacterial Species ◽

Fruit Fly ◽

Pathogen Transmission ◽

Commensal Bacteria ◽

Parasitic Nematodes ◽

Intracellular Bacteria ◽

Key Factor

ABSTRACT Wolbachia bacteria are intracellular bacteria present in the microbiome of a large fraction of insects and parasitic nematodes. They can block mosquitos’ ability to transmit several infectious disease-causing pathogens, including Zika, dengue, chikungunya, and West Nile viruses and malaria parasites. Certain extracellular bacteria present in the gut lumen of these insects can also block pathogen transmission. However, our understanding of interactions between Wolbachia and gut bacteria and how they influence each other is limited. Here we show that the presence of Wolbachia strain wMel changes the composition of gut commensal bacteria in the fruit fly. Our findings implicate interactions between bacterial species as a key factor in determining the overall composition of the microbiome and thus reveal new paradigms to consider in the development of disease control strategies. Endosymbiotic Wolbachia bacteria and the gut microbiome have independently been shown to affect several aspects of insect biology, including reproduction, development, life span, stem cell activity, and resistance to human pathogens, in insect vectors. This work shows that Wolbachia bacteria, which reside mainly in the fly germline, affect the microbial species present in the fly gut in a lab-reared strain. Drosophila melanogaster hosts two main genera of commensal bacteria—Acetobacter and Lactobacillus. Wolbachia-infected flies have significantly reduced titers of Acetobacter. Sampling of the microbiome of axenic flies fed with equal proportions of both bacteria shows that the presence of Wolbachia bacteria is a significant determinant of the composition of the microbiome throughout fly development. However, this effect is host genotype dependent. To investigate the mechanism of microbiome modulation, the effect of Wolbachia bacteria on Imd and reactive oxygen species pathways, the main regulators of immune response in the fly gut, was measured. The presence of Wolbachia bacteria does not induce significant changes in the expression of the genes for the effector molecules in either pathway. Furthermore, microbiome modulation is not due to direct interaction between Wolbachia bacteria and gut microbes. Confocal analysis shows that Wolbachia bacteria are absent from the gut lumen. These results indicate that the mechanistic basis of the modulation of composition of the microbiome by Wolbachia bacteria is more complex than a direct bacterial interaction or the effect of Wolbachia bacteria on fly immunity. The findings reported here highlight the importance of considering the composition of the gut microbiome and host genetic background during Wolbachia-induced phenotypic studies and when formulating microbe-based disease vector control strategies. IMPORTANCE Wolbachia bacteria are intracellular bacteria present in the microbiome of a large fraction of insects and parasitic nematodes. They can block mosquitos’ ability to transmit several infectious disease-causing pathogens, including Zika, dengue, chikungunya, and West Nile viruses and malaria parasites. Certain extracellular bacteria present in the gut lumen of these insects can also block pathogen transmission. However, our understanding of interactions between Wolbachia and gut bacteria and how they influence each other is limited. Here we show that the presence of Wolbachia strain wMel changes the composition of gut commensal bacteria in the fruit fly. Our findings implicate interactions between bacterial species as a key factor in determining the overall composition of the microbiome and thus reveal new paradigms to consider in the development of disease control strategies.

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Tissue section lifting for electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081292 ◽

1978 ◽

Vol 36 (2) ◽

pp. 86-87

Author(s):

Adrian F. van Dellen

Keyword(s):

Infectious Disease ◽

Electron Microscopy ◽

Tissue Culture ◽

Organ System ◽

Surrounding Tissue ◽

Paraffin Sections ◽

Surface Areas ◽

Specific Determination ◽

High Degree ◽

Accuracy And Repeatability

The morphologic pathologist may require information on the ultrastructure of a non-specific lesion seen under the light microscope before he can make a specific determination. Such lesions, when caused by infectious disease agents, may be sparsely distributed in any organ system. Tissue culture systems, too, may only have widely dispersed foci suitable for ultrastructural study. In these situations, when only a few, small foci in large tissue areas are useful for electron microscopy, it is advantageous to employ a methodology which rapidly selects a single tissue focus that is expected to yield beneficial ultrastructural data from amongst the surrounding tissue. This is in essence what "LIFTING" accomplishes. We have developed LIFTING to a high degree of accuracy and repeatability utilizing the Microlift (Fig 1), and have successfully applied it to tissue culture monolayers, histologic paraffin sections, and tissue blocks with large surface areas that had been initially fixed for either light or electron microscopy.

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Attachment of oral bacteria to titanium surfaces: An SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170074 ◽

1994 ◽

Vol 52 ◽

pp. 468-469

Author(s):

J. E. Laffoon ◽

R. L. Anderson ◽

J. C. Keller ◽

C. D. Wu-Yuan

Keyword(s):

Technical Problem ◽

Titanium Implant ◽

Oral Bacteria ◽

Bacterial Cells ◽

Thin Sections ◽

Surface Ultrastructure ◽

Sem Study ◽

Key Factor ◽

Titanium Surfaces

Titanium (Ti) dental implants have been used widely for many years. Long term implant failures are related, in part, to the development of peri-implantitis frequently associated with bacteria. Bacterial adherence and colonization have been considered a key factor in the pathogenesis of many biomaterial based infections. Without the initial attachment of oral bacteria to Ti-implant surfaces, subsequent polymicrobial accumulation and colonization leading to peri-implant disease cannot occur. The overall goal of this study is to examine the implant-oral bacterial interfaces and gain a greater understanding of their attachment characteristics and mechanisms. Since the detailed cell surface ultrastructure involved in attachment is only discernible at the electron microscopy level, the study is complicated by the technical problem of obtaining titanium implant and attached bacterial cells in the same ultra-thin sections. In this study, a technique was developed to facilitate the study of Ti implant-bacteria interface.Discs of polymerized Spurr’s resin (12 mm x 5 mm) were formed to a thickness of approximately 3 mm using an EM block holder (Fig. 1). Titanium was then deposited by vacuum deposition to a film thickness of 300Å (Fig. 2).

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Indian vultures: victims of an infectious disease epidemic?

Animal Conservation ◽

10.1017/s136794300300324x ◽

2003 ◽

Vol 6 (3) ◽

pp. 189-197 ◽

Cited By ~ 23

Author(s):

A. A. Cunningham ◽

V. Prakash ◽

D. Pain ◽

G. R. Ghalsasi ◽

G. A. H. Wells ◽

...

Keyword(s):

Infectious Disease

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Forum: Morphological Awareness as a Key Factor in Language-Literacy Success for Academic Achievement

Language Speech and Hearing Services in Schools ◽

10.1044/2020_lshss-20-00064 ◽

2020 ◽

Vol 51 (3) ◽

pp. 509-513

Author(s):

Ashley Bourque Meaux ◽

Julie A. Wolter ◽

Ginger G. Collins

Keyword(s):

Academic Achievement ◽

Academic Success ◽

Literacy Development ◽

Morphological Awareness ◽

Language And Literacy ◽

Speech Language Pathologists ◽

School Based ◽

Literacy Success ◽

Key Factor ◽

Language And Literacy Development

Purpose This article introduces the Language, Speech, and Hearing Services in Schools Forum: Morphological Awareness as a Key Factor in Language-Literacy Success for Academic Achievement. The goal of this forum is to relate the influence morphological awareness (MA) has on overall language and literacy development with morphology acting as the “binding agent” between orthography, phonology, and semantics ( Perfetti, 2007 ) in assessment and intervention for school-aged children. Method This introduction provides a foundation for MA development and explores the influence MA has over the course of school-aged language and literacy development. Through summaries of the 11 articles in this forum, school-based speech-language pathologists will be able to convey the importance of MA to promote successful educational outcomes for kindergarten to adolescent students. The forum explores researcher-developed assessments used to help identify MA skill level in first- through eighth-grade students at risk for literacy failure to support instructional needs. The forum also provides school-based speech-language pathologists with details to design and implement MA interventions to support academic success for school-aged students with varying speech-language needs (e.g., dual language emersion, vocabulary development, reading comprehension) using various service delivery models (e.g., small group, classroom-based, intensive summer camps). Conclusion MA is effective in facilitating language and literacy development and as such can be an ideally focused on using multilinguistic approaches for assessment and intervention. The articles in this issue highlight the importance in assessment measures and intervention approaches that focus on students' MA to improve overall academic success in children of all ages and abilities.

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