scholarly journals Expressão de microRNAs em trofoblastos infectados \"in vitro\" por vírus Zika e Chikungunya, e estabelecimento de um modelo experimental da transmissão vertical de vírus Chikungunya na gestação e lactação

2021 ◽  
Author(s):  
Juliano de Paula Souza
Keyword(s):  
Virus Zika

scholarly journals Pesquisa de epítopos virais in silico utilizando bioinformática na fabricação de imunoterápicos de relevância clínica

2019 ◽  
Vol 4 (1) ◽  
Author(s):  
João Paulo Romualdo Alarcão Bernardes ◽  
Sarah Maria da Silva Napoleão ◽  
Kelly Cristina Simi
Keyword(s):  
In Silico ◽  
Virus Zika

A imunologia é a ciência que estuda os mecanismos utilizados pelo nosso organismo no combate a patógenos tais como os vírus Zika e Chikungunya. A bioinformática é uma ciência recente que permite o estudo de diversos processos imunológicos através de softwares de computador. A utilização de ferramentas oriundas da bioinformática possibilita o estudo e predição de estruturas proteicas de diversos patógenos. Esses estudos geralmente estão relacionados com pesquisas de sequências proteicas em banco de dados, para formulação de estruturas tridimensionais de proteínas e predição de epítopos virais que possam gerar uma resposta efetiva do sistema imunológico. Os resultados dessa pesquisa auxiliam no processo de formulação e fabricação de moléculas para utilização em terapias alternativas, como a imunoterapia e desenvolvimento de vacinas, que pudesse ser mais eficiente e específico antes do início de testes em bancada, otimizando assim tempo e recursos. A metodologia utilizada foi aquisição dos epítopos através do banco de dados IEDB, em seguida foi feito reconhecimento das proteínas encontradas pelo site UniProt, foi feita também a análise conformacional das proteínas encontradas e validadas juntamente com o processo de validação in silico dos epítopos encontrados pelo próprio IEDB, a partir desses achados foi possível fazer o rank dos epítopos mais promissores. Foi possível utilizar estratégia de filtragem de dados para proporcionar informações básicas e relevantes para processos como modelagem de proteínas 3D e sugestão de alelos que podem ser utilizados em experimentos in vitro. A pesquisa in silico é um método de pesquisa muito recente e promissor, e se faz necessário o estudo nessa área para auxiliar os métodos in vitro e in vivo da predição de epítopos relevantes para fabricação de vacinas e imunoterápicos

scholarly journals Lipid Droplet Motility Increases Following Viral Immune Stimulation

2021 ◽  
Vol 22 (9) ◽  
pp. 4418
Author(s):  
Ebony A. Monson ◽  
Donna R. Whelan ◽  
Karla J. Helbig
Keyword(s):  
Lipid Droplets ◽  
Time Course ◽  
Rna Virus ◽  
Poly I:C ◽  
Host Responses ◽  
Immune Stimulation ◽  
Health And Disease ◽  
Infected Cells ◽  
Virus Zika

Lipid droplets (LDs) have traditionally been thought of as solely lipid storage compartments for cells; however, in the last decade, they have emerged as critical organelles in health and disease. LDs are highly dynamic within cells, and their movement is critical in organelle–organelle interactions. Their dynamics are known to change during cellular stress or nutrient deprivation; however, their movement during pathogen infections, especially at very early timepoints, is under-researched. This study aimed to track LD dynamics in vitro, in an astrocytic model of infection. Cells were either stimulated with a dsRNA viral mimic, poly I:C, or infected with the RNA virus, Zika virus. Individual LDs within infected cells were analysed to determine displacement and speed, and average LD characteristics for multiple individual cells calculated. Both LD displacement and mean speed were significantly enhanced in stimulated cells over a time course of infection with an increase seen as early as 2 h post-infection. With the emerging role for LDs during innate host responses, understanding their dynamics is critical to elucidate how these organelles influence the outcome of viral infection.

scholarly journals Inhibition of Polyamine Biosynthesis Is a Broad-Spectrum Strategy against RNA Viruses

2016 ◽  
Vol 90 (21) ◽  
pp. 9683-9692 ◽  
Author(s):  
Bryan C. Mounce ◽  
Teresa Cesaro ◽  
Gonzalo Moratorio ◽  
Peter Jan Hooikaas ◽  
Anna Yakovleva ◽  
...  
Keyword(s):  
Viral Replication ◽  
Human Health ◽  
Ebola Virus ◽  
Rna Viruses ◽  
Polyamine Biosynthesis ◽  
Recent Emergence ◽  
Virus Zika ◽  
Positively Charged

ABSTRACT RNA viruses present an extraordinary threat to human health, given their sudden and unpredictable appearance, the potential for rapid spread among the human population, and their ability to evolve resistance to antiviral therapies. The recent emergence of chikungunya virus, Zika virus, and Ebola virus highlights the struggles to contain outbreaks. A significant hurdle is the availability of antivirals to treat the infected or protect at-risk populations. While several compounds show promise in vitro and in vivo , these outbreaks underscore the need to accelerate drug discovery. The replication of several viruses has been described to rely on host polyamines, small and abundant positively charged molecules found in the cell. Here, we describe the antiviral effects of two molecules that alter polyamine levels: difluoromethylornithine (DFMO; also called eflornithine), which is a suicide inhibitor of ornithine decarboxylase 1 (ODC1), and diethylnorspermine (DENSpm), an activator of spermidine/spermine N 1 -acetyltransferase (SAT1). We show that reducing polyamine levels has a negative effect on diverse RNA viruses, including several viruses involved in recent outbreaks, in vitro and in vivo . These findings highlight the importance of the polyamine biosynthetic pathway to viral replication, as well as its potential as a target in the development of further antivirals or currently available molecules, such as DFMO. IMPORTANCE RNA viruses present a significant hazard to human health, and combatting these viruses requires the exploration of new avenues for targeting viral replication. Polyamines, small positively charged molecules within the cell, have been demonstrated to facilitate infection for a few different viruses. Our study demonstrates that diverse RNA viruses rely on the polyamine pathway for replication and highlights polyamine biosynthesis as a promising drug target.

Ultrastructural Investigations of the Contractile Filaments of Amoebae

1974 ◽  
Vol 32 ◽  
pp. 188-189
Author(s):  
P.L. Moore
Keyword(s):  
Cytoplasmic Streaming ◽  
Three Dimensional ◽  
Freeze Fracture ◽  
Amoeboid Movement ◽  
Different Types ◽  
Chemical Conditions ◽  
Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

In Vitro Induction of Crystals of MT Protein by Vinblastine-Colcemid in Mouse Spermatids

1974 ◽  
Vol 32 ◽  
pp. 132-133
Author(s):  
John J. Wolosewick ◽  
John H. D. Bryan
Keyword(s):  
Endoplasmic Reticulum ◽  
Smooth Endoplasmic Reticulum ◽  
Nuclear Ring ◽  
Rough Er ◽  
Distal Direction ◽  
In Vitro Induction

Early in spermiogenesis the manchette is rapidly assembled in a distal direction from the nuclear-ring-densities. The association of vesicles of smooth endoplasmic reticulum (SER) and the manchette microtubules (MTS) has been reported. In the mouse, osmophilic densities at the distal ends of the manchette are the organizing centers (MTOCS), and are associated with the SER. Rapid MT assembly and the lack of rough ER suggests that there is an existing pool of MT protein. Colcemid potentiates the reaction of vinblastine with tubulin and was used in this investigation to detect this protein.

Induction and Differentiation of Dental Epithelium in Vivo and in Vitro

1982 ◽  
Vol 40 ◽  
pp. 142-145
Author(s):  
E. J. Kollar
Keyword(s):  
Connective Tissue ◽  
Oral Mucosa ◽  
Basal Lamina ◽  
Functional Derivatives ◽  
Specific Source ◽  
Dental Epithelium ◽  
Connective Tissue Stroma

The differentiation and maintenance of many specialized epithelial structures are dependent on the underlying connective tissue stroma and on an intact basal lamina. These requirements are especially stringent in the development and maintenance of the skin and oral mucosa. The keratinization patterns of thin or thick cornified layers as well as the appearance of specialized functional derivatives such as hair and teeth can be correlated with the specific source of stroma which supports these differentiated expressions.

Immunoenzymatic demonstration of the simultaneous presence of transferrin, hemopexin and albumin in a same hepatocyte and their ultrastructural localization

1978 ◽  
Vol 36 (2) ◽  
pp. 88-89
Author(s):  
M. Kraemer ◽  
J. Foucrier ◽  
J. Vassy ◽  
M.T. Chalumeau
Keyword(s):  
Plasma Proteins ◽  
Rat Hepatocytes ◽  
Ultrastructural Localization ◽  
Carrier Proteins ◽  
Normal Cells ◽  
Adult Rat ◽  
Adult Rat Hepatocytes ◽  
Monospecific Antisera ◽  
Different Levels

Some authors using immunofluorescent techniques had already suggested that some hepatocytes are able to synthetize several plasma proteins. In vitro studies on normal cells or on cells issued of murine hepatomas raise the same conclusion. These works could be indications of an hepatocyte functionnal non-specialization, meanwhile the authors never give direct topographic proofs suitable with this hypothesis.The use of immunoenzymatic techniques after obtention of monospecific antisera had seemed to us useful to bring forward a better knowledge of this problem. We have studied three carrier proteins (transferrin = Tf, hemopexin = Hx, albumin = Alb) operating at different levels in iron metabolism by demonstrating and localizing the adult rat hepatocytes involved in their synthesis.Immunological, histological and ultrastructural methods have been described in a previous work.

Sem Studies of Co-Cr-Mo Surgical Implant Alloy Corrosion Behavior

1982 ◽  
Vol 40 ◽  
pp. 520-521
Author(s):  
Ann Chidester Van Orden ◽  
John L. Chidester ◽  
Anna C. Fraker ◽  
Pei Sung
Keyword(s):  
Electron Microscopy ◽  
Corrosion Behavior ◽  
Anodic Polarization ◽  
Saline Solution ◽  
Saturated Calomel Electrode ◽  
Physiological Saline ◽  
X Ray ◽  
Physiological Saline Solution ◽  
Scanning Electron

The influence of small variations in the composition on the corrosion behavior of Co-Cr-Mo alloys has been studied using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), and electrochemical measurements. SEM and EDX data were correlated with data from in vitro corrosion measurements involving repassivation and also potentiostatic anodic polarization measurements. Specimens studied included the four alloys shown in Table 1. Corrosion tests were conducted in Hanks' physiological saline solution which has a pH of 7.4 and was held at a temperature of 37°C. Specimens were mechanically polished to a surface finish with 0.05 µm A1203, then exposed to the solution and anodically polarized at a rate of 0.006 v/min. All voltages were measured vs. the saturated calomel electrode (s.c.e.).. Specimens had breakdown potentials near 0.47V vs. s.c.e.

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