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Rabies virus (RABV) is a neurotropic virus exclusively infecting neurons in the central nervous system. RABV encodes five proteins. Among them, the viral glycoprotein (RVG) plays a key role in viral entry into neurons and rabies pathogenesis. It was shown that the nature of the C-terminus of the RABV G protein, which possesses a PDZ-binding motif (PBM), modulates the virulence of the RABV strain. The neuronal protein partners recruited by this PBM may alter host cell function. This study was conducted to investigate the effect of RVG on synaptic function in the hippocampal dentate gyrus (DG) of rat. Two µl (108 T.U./ml) of the lentiviral vector containing RVG gene was injected into the DG of rat hippocampus. After 2 weeks, the rat's brain was cross-sectioned and RVG-expressing cells were detected by fluorescent microscopy. Hippocampal synaptic activity of the infected rats was then examined by recording the local field potentials from DG after stimulation of the perforant pathway. Short-term synaptic plasticity was also assessed by double pulse stimulation. Expression of RVG in DG increased long-term potentiation population spikes (LTP-PS), whereas no facilitation of LTP-PS was found in neurons expressing δRVG (deleted PBM). Furthermore, RVG and δRVG strengthened paired-pulse facilitation. Heterosynaptic long-term depression (LTD) in the DG was significantly blocked in RVG-expressing group compared to the control group. This blockade was dependent to PBM motif as rats expressing δRVG in the DG-expressed LTD comparable to the RVG group. Our data demonstrate that RVG expression facilitates both short- and long-term synaptic plasticity in the DG indicating that it may involve both pre- and postsynaptic mechanisms to alter synaptic function. Further studies are needed to elucidate the underlying mechanisms.
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Vírus da Raiva , Animais , Giro Denteado/metabolismo , Estimulação Elétrica , Glicoproteínas/genética , Glicoproteínas/metabolismo , Glicoproteínas/farmacologia , Hipocampo/metabolismo , Potenciação de Longa Duração , Plasticidade Neuronal/fisiologia , Vírus da Raiva/metabolismo , RatosRESUMO
Rabies is a life-threatening viral infection of the brain. Rabies virus (RABV) merely infects excitable cells including neurons provoking drastic behaviors including negative emotional memories. RABV glycoprotein (RVG) plays a critical role in RABV pathogenesis. RVG interacts with various cytoplasmic PDZ (PSD-95/Dlg/ZO-1) containing proteins through its PDZ binding motif (PBM). PTZ domains have crucial role in formation and function of signal transduction. Hippocampus is one of the cerebral regions that contain high load of viral antigens. We examined impact of RVG expression in the dorsal hippocampus on aversive as well as spatial learning and memory performance in rats. Two microliter of the lentiviral vector (~108 T.U./ml) encoding RVG or ∆RVG (deleted PBM) genomes was microinjected into the hippocampal CA1. After 1 week, rat's brain was cross-sectioned and RVG/∆RVG-expressing neuronal cells were confirmed by fluorescent microscopy. Passive avoidance and spatial learning and memory were assessed in rats by Shuttle box and Morris water maze (MWM). In the shuttle box, both RVG and ∆RVG decreased the time spent in the dark compartment compared to control (p < 0.05). In MWM, RVG and ∆RVG did not affect the acquisition of spatial task. In the probe test, RVG-expressing rats spent more time in the target quadrant, and also reached the platform position sooner than control group (p < 0.05). Rats expressing ∆RVG significantly swam farther from the hidden platform than RVG group (p < 0.05). Our data indicate RVG expression in the hippocampus strengthens aversive and spatial learning and memory performance. The boosting effect on spatial but not avoidance memory is mediated through PBM.
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Aprendizagem da Esquiva , Região CA1 Hipocampal/fisiopatologia , Glicoproteínas/genética , Aprendizagem em Labirinto , Vírus da Raiva/genética , Memória Espacial , Proteínas Virais/genética , Animais , Região CA1 Hipocampal/metabolismo , Expressão Gênica , Genes Reporter , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Glicoproteínas/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Injeções Intraventriculares , Lentivirus/genética , Lentivirus/metabolismo , Masculino , Neurônios/metabolismo , Neurônios/patologia , Vírus da Raiva/química , Vírus da Raiva/metabolismo , Ratos , Ratos Wistar , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Técnicas Estereotáxicas , Transgenes , Proteínas Virais/metabolismoRESUMO
Rabies is always fatal, when post-exposure prophylaxis is administered after the onset of clinical symptoms. To date, there is no effective treatment of rabies once clinical symptoms has initiated. Therefore, we aimed to provide evidences which indicate the promising effects of combination treatment with TLR agonists following rabies infection. Four groups of rabies infected-mice (10-mice/group) were treated with PolyI:C 50 µg (a TLR3 agonist), Imiquimod50 µg (a TLR7 agonist), (Poly + Imi)25 µg and (Poly + Imi)50 µg respectively. The immune responses in each experimental groups were investigated in the brain through evaluation of GFAP, MAP2, CD4, HSP70, TLR3, TLR7 and apoptotic cell expression as well as determination of IFN-γ, TNF-α and IL-4, levels. The treatment with combination of agonists (Poly + Imi)50 µg/mouse resulted a 75% decrease of mortality rate and better extended survival time following street rabies virus infection. Higher number of CD4+T cells, TLR3 and TLR7 expression in the brain parenchyma observed in the groups receiving both combined agonist therapies at the levels of 25 µg and 50 µg. In spite of decreased number of neuronal cell, significant higher number of astrocytes was shown in the group given (Poly + Imi)25 µg. The obtained results also pointed to the dramatic decrease of HSP70 expression in all groups of infected mice whereas higher number of apoptotic cells and Caspase 8 expression were recorded in (Poly + Imi)25 µg treated group. Furthermore, the cytokine profile consisting the increased levels of TNF-α, IFN-γ and IL-4 revealed that both humoral and cellular responses were highly modulated in combination therapy of 50 µg of Imiquimod and Poly I:C. Reduced viral load as quantified by real-time PCR of rabies N gene expression in the brain also correlated with the better survival of agonist-treated groups of mice. Based on obtained results, we have presented evidences of beneficial utilization of combined agonist therapy composed of TLR3/TLR7 ligands. This treatment regimen extended survival of infected mice and decreased significantly their mortality rate. We believe that the results of synergy-inducing protection of both TLR3/TLR7 agonists lead to the enhancement of innate immune responses cells residing in the CNS which warrant the studies to further understanding of crosstalk mechanisms in cellular immunity against rabies in the future.
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Raiva , Receptor 3 Toll-Like/agonistas , Receptor 7 Toll-Like/agonistas , Animais , Imunidade Inata , Camundongos , Raiva/tratamento farmacológico , Raiva/imunologia , Vírus da RaivaRESUMO
The present work aims at optimization and advanced simulation of removal efficiency of dye material from a synthetic wastewater using a locally generated rhamnolipid (RL) biosurfactant. For this purpose, bio-treatment of dye polluted synthetic wastewater was experimentally, kinetically, and statistically investigated by the ion flotation process in the presence of the RL. The removal rate of methylene blue (MB) as the dye material was assessed by the ultraviolet (UV)-visible absorbance measurements. The impact of operating variables including RL concentration (as a dye collector, 5-50 ppm), methyl isobutyl carbinol (MIBC) dosage (as a frother, 10-70 ppm), solution pH (2-12) and aeration rate (1-5 l/min) were assessed through one-way analysis of variance (ANOVA) and Anderson-Darling as the normality analysis strategy. The process was simulated using two artificial neural network (ANN) optimization algorithms, i.e., genetic algorithm (GA) and artificial bee colony (ABC) as a novel approach. The statistical results indicated that the dye removal process was significantly influenced by all operating variables (pvalue<0.05) while their relative intensity followed the order of aeration rate > solution pH > RL concentration > MIBC dosage. Anderson-Darling approach disclosed that the all factors were perfectly followed the normal trend with A2 less than unity and p-value of greater than 0.05 at 95% confidence level. Main effect plots revealed that except MIBC dosage with nonlinear trend, the rest of factors had an ascending influence on the removal efficiency. The process was optimized by interpreting the interaction effect among various variables to reach the maximum dye bioflotation. The maximum removal of 97 ± 0.13% was achieved at pH 12, airflow rate of 5 l/min, MIBC and rhamnolipid concentrations of 30 and 40 ppm, respectively with a flotation kinetic rate of 0.015 sec-1. Finally, the intelligent simulation results showed that the process could be modelled using an artificial bee colony algorithm of 4-7-1 structure with 99% and 98.8% accuracies in the training and testing steps, respectively. Further, we found that the artificial bee colony algorithm was superior to the genetic algorithm in terms of complexity analysis.
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Algoritmos , Águas Residuárias , Glicolipídeos , Redes Neurais de ComputaçãoRESUMO
Recent years have seen the extensive use of phylogeographic approaches to unveil the dispersal history of virus epidemics. Spatially explicit reconstructions of viral spread represent valuable sources of lineage movement data that can be exploited to investigate the impact of underlying environmental layers on the dispersal of pathogens. Here, we performed phylogeographic inference and applied different post hoc approaches to analyse a new and comprehensive data set of viral genomes to elucidate the dispersal history and dynamics of rabies virus (RABV) in Iran, which have remained largely unknown. We first analysed the association between environmental factors and variations in dispersal velocity among lineages. Second, we present, test and apply a new approach to study the link between environmental conditions and the dispersal direction of lineages. The statistical performance (power of detection, false-positive rate) of this new method was assessed using simulations. We performed phylogeographic analyses of RABV genomes, allowing us to describe the large diversity of RABV in Iran and to confirm the cocirculation of several clades in the country. Overall, we estimate a relatively high lineage dispersal velocity, similar to previous estimates for dog rabies virus spread in northern Africa. Finally, we highlight a tendency for RABV lineages to spread in accessible areas associated with high human population density. Our analytical workflow illustrates how phylogeographic approaches can be used to investigate the impact of environmental factors on several aspects of viral dispersal dynamics.
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Filogeografia , Vírus da Raiva/classificação , Raiva/transmissão , Raiva/virologia , Teorema de Bayes , Irã (Geográfico)/epidemiologia , Raiva/epidemiologiaRESUMO
Extensive research efforts have been dedicated to developing electrode materials with high capacity to address the increasing complexities arising from the energy crisis. Herein, a new nanocomposite was synthesized via the sol-gel method by immobilizing K6ZnW12O40 within the surface of NiZn2O4. ZnW12O40@NiZn2O4 was characterized by FT-IR, UV-Vis, XRD, SEM, EDX, BET, and TGA-DTG methods. The electrochemical characteristics of the materials were examined using cyclic voltammogram (CV) and charge-discharge chronopotentiometry (CHP) techniques. Multiple factors affecting the hydrogen storage capacity, including current density (j), surface area of the copper foam, and the consequences of repeated cycles of hydrogen adsorption-desorption were evaluated. The initial cycle led to an impressive hydrogen discharge capability of 340 mAh/g, which subsequently increased to 900 mAh/g after 20 cycles with a current density of 2 mA in 6.0 M KOH medium. The surface area and the electrocatalytic characteristics of the nanoparticles contribute to facilitate the formation of electrons and provide good diffusion channels for the movement of electrolyte ions throughout the charge-discharge procedure.
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In this study, a new and recyclable biocatalyst (MgAl CO3-LDH@Asn) was synthesized by immobilizing l-asparagine amino acid (Asn) on the surface of 3-(chloropropyl)-trimethoxysilane modified MgAl CO3-layered double hydroxide (LDH). The physicochemical properties of the samples were identified by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and thermogravimetric analysis (TGA) techniques. The MgAl CO3-LDH@Asn was employed in the multi-component assembly process for the synthesis of tri-substituted derivatives of 2,4,5-(H1)-imidazoles from benzyl, various benzaldehyde derivatives, and ammonium acetate. For optimizing the reaction, the main factors, including the amount of MgAl CO3-LDH@Asn, type of solvent, reaction time, and temperature were evaluated. The optimum conditions of the model reaction were achieved using 20 mg of MgAl CO3-LDH@Asn biocatalyst in ethanol solvent after 20 min at reflux temperature. According to the findings above, the results indicated that high-yield products are achieved within a short time frame. Moreover, the high catalytic activity of the MgAl CO3-LDH@Asn was maintained for four cycles without significantly diminishing its performance.
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The lyssavirus matrix (M) protein induces apoptosis. The regions of the M protein that are essential for triggering cell death pathways are not yet clearly defined. We therefore compared the M proteins from two viruses that have contrasting characteristics in terms of cellular apoptosis: a genotype 3 lyssavirus, Mokola virus (MOK), and a genotype 1 rabies virus isolated from a dog from Thailand (THA). We identified a 20-amino-acid fragment (corresponding to positions 67 to 86) that retained the cell death activities of the full-length M protein from MOK via both the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and inhibition of cytochrome c oxidase (CcO) activity. We found that the amino acids at positions 77 and 81 have an essential role in triggering these two cell death pathways. Directed mutagenesis demonstrated that the amino acid at position 77 affects CcO activity, whereas the amino acid at position 81 affects TRAIL-dependent apoptosis. Mutations in the full-length M protein that compromised induction of either of these two pathways resulted in delayed apoptosis compared with the time to apoptosis for the nonmutated control.
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Lyssavirus/fisiologia , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/fisiologia , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Apoptose/fisiologia , Sequência de Bases , Primers do DNA/genética , DNA Viral/genética , Cães , Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Células HeLa , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Lyssavirus/genética , Lyssavirus/patogenicidade , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Estrutura Terciária de Proteína , Vírus da Raiva/genética , Vírus da Raiva/patogenicidade , Vírus da Raiva/fisiologia , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/fisiologia , Proteínas da Matriz Viral/genéticaRESUMO
This work aims at presenting an advanced simulation approach for a novel rhamnolipidic-based bioflotation process to remove chromium from wastewater. For this purpose, the significance of key influential operating variables including initial solution pH (2, 4, 6, 8, 10 and 12), rhamnolipid to chromium ratio (RL:Cr = 0.010, 0.025, 0.050, 0.075 and 0.100), reductant (Fe) to chromium ratio (Fe:Cr of 0.5, 1.0, 1.5, 2.0, 2.5, 3.0), and air flowrate (50, 100, 150, 200 and 250 mL/min) were investigated and evaluated using Analysis of Variance (ANOVA) method. The RL as both collector and frother was produced using a pure strain of Pseudomonas aeruginosa MA01 under specific conditions. The bioflotation tests were carried out within a bubbly regimed column cell with the dimensions of 60 × 5.70 × 0.1 cm. Four optimization techniques based on Artificial Neural Network (ANN) including Cuckoo, genetic, firefly and biogeography-based optimization algorithms were applied to 113 experiments to identify the optimum values of studied factors. The ANOVA results revealed that all four variables influence the bioflotation performance through a non-linear trend. Their influences, except for aeration rate, were found statistically significant (p-value < 0.05), and all parameters followed the normal distribution according to Anderson-Darlin (AD) criterion. Maximum chromium removal of about 98% was achieved at pH of 6, rhamnolipid to chromium ratio of 0.05, air flowrate of 150 mL/min, and Fe to Cr ratio of 1.0. Flotation kinetics study indicated that chromium bioflotation follows the first-order kinetic model with a rate of 0.023 sec-1. According to the statistical assessment of the model accuracy, the firefly algorithm (FFA) with a structure of 4-9-1 yielded the highest level of reliability with the mean squared, root mean squared, percentage errors and correlation coefficient values of test-data of 0.0038, 0.0617, 3.08% and 96.92%, respectively. These values were evidences of the consistency of the well-structured ANN method to simulate the process.
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OBJECTIVES: The mechanisms of rabies evasion and immunological interactions with the host defense have not been completely elucidated. Here, we evaluated the dynamic changes in the number of astrocytes, microglial and neuronal cells in the brain following intramuscular (IM) and intracerebral (IC) inoculations of street rabies virus (SRV). MATERIALS AND METHODS: The SRV isolated from a jackal and CVS-11 were used to establish infection in NMRI-female mice. The number of astrocytes (by expression of GFAP), microglial (by Iba1), and neuronal cells (by MAP-2) in the brain following IM and IC inoculations of SRV were evaluated by immunohistochemistry and H & E staining 7 to 30 days post-infection. RESULTS: Increased numbers of astrocytes and microglial cells in dead mice infected by SRV via both IC and IM routes were recorded. The number of neuronal cells in surviving mice was decreased only in IC-infected mice, while in the dead group, this number was decreased by both routes.The risk of death in SRV-infected mice was approximately 3 times higher than in the CVS-11 group. In IC-inoculated mice, viral dilution was the only influential factor in mortality, while the type of strain demonstrated a significant impact on the mortality rate in IM inoculations. CONCLUSION: Our results suggested that microglial cells and their inflammatory cytokines may not contribute to the neuroprotection and recovery in surviving mice following intracerebral inoculation of SRV. An unexpected decrease in MAP2 expression via intramuscular inoculation indicates the imbalance in the integrity and stability of neuronal cytoskeleton which aggravates rabies infection.
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Multifunctional matrix protein (M) of rabies virus (RABV) plays essential roles in the pathogenesis of rabies infection. Identification of M protein interacting partners in target hosts could help to elucidate the biological pathways and molecular mechanisms involved in the pathogenesis of this virus. In this study, two-dimensional Far-western blotting (2D-Far-WB) technique was applied to find possible matrix protein partners in the rat brainstem. Recombinant RABV M was expressed in Pichia pastoris and was partially purified. Subsequently, 2D-Far-WB-determined six rat brainstem proteins interacted with recombinant M proteins that were identified by mass spectrometry. Functional annotation by gene ontology analysis determined these proteins were involved in the regulation of synaptic transmission processes, metabolic process and cell morphogenesis-cytoskeleton organization. The interaction of viral M protein with selected host proteins in mouse Neuro-2a cells infected with RABV was verified by super-resolution confocal microscopy. Molecular docking simulations also demonstrated the formation of RABV M complexes. However, further confirmation with co-immunoprecipitation was only successful for M-actin cytoplasmic 1 interaction. Our study revealed actin cytoplasmic 1 as a binding partner of M protein, which might have important role(s) in rabies pathogenesis.
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Citoesqueleto de Actina/metabolismo , Interações entre Hospedeiro e Microrganismos , Vírus da Raiva/química , Vírus da Raiva/metabolismo , Raiva/metabolismo , Raiva/virologia , Proteínas da Matriz Viral/metabolismo , Citoesqueleto de Actina/química , Animais , Western Blotting/métodos , Linhagem Celular , Eletroforese em Gel Bidimensional/métodos , Gliceraldeído-3-Fosfato Desidrogenases/química , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Masculino , Camundongos , Simulação de Acoplamento Molecular , Ligação Proteica , Ratos , Ratos Wistar , Proteínas Recombinantes/metabolismo , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Proteínas da Matriz Viral/químicaRESUMO
The matrix (M) proteins of rhabdoviruses are multifunctional proteins essential for virus maturation and budding that also regulate the expression of viral and host proteins. We have solved the structures of M from the vesicular stomatitis virus serotype New Jersey (genus: Vesiculovirus) and from Lagos bat virus (genus: Lyssavirus), revealing that both share a common fold despite sharing no identifiable sequence homology. Strikingly, in both structures a stretch of residues from the otherwise-disordered N terminus of a crystallographically adjacent molecule is observed binding to a hydrophobic cavity on the surface of the protein, thereby forming non-covalent linear polymers of M in the crystals. While the overall topology of the interaction is conserved between the two structures, the molecular details of the interactions are completely different. The observed interactions provide a compelling model for the flexible self-assembly of the matrix protein during virion morphogenesis and may also modulate interactions with host proteins.
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Multimerização Proteica/fisiologia , Rhabdoviridae/metabolismo , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/metabolismo , Montagem de Vírus/fisiologia , Sequência de Aminoácidos , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Rhabdoviridae/química , Rhabdoviridae/classificação , Homologia de Sequência de Aminoácidos , Sorotipagem , Vírus da Estomatite Vesicular New Jersey/química , Vírus da Estomatite Vesicular New Jersey/metabolismoRESUMO
Rabies constantly kills 59,000 people annually, mostly in Asia and Africa. Rabies, which is responsible for 99% of human rabies cases, is totally preventable by standard vaccinations. In 2015, a global call for action was made by the World Health Organization, World Organization for Animal Health, Food and Agriculture Organization of the United Nations, and the Global Alliance for Rabies Control to join forces toward the elimination of dog-transmitted human rabies by the year 2030. All the tools and protocols to reach that target are readily available, and the feasibility of dog rabies elimination has been proven. Countries should drive the changes needed to engage into this global movement. Certainly, countries in the Eastern Mediterranean Region require taking more critical steps to reach the rabies elimination target by 2030. The international awareness campaign of the World Rabies Day is an excellent occasion to assess challenges and opportunities toward rabies elimination.
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Comportamento Cooperativo , Raiva/imunologia , Vacinação , Animais , Humanos , Internacionalidade , Raiva/epidemiologiaRESUMO
Rabies is acute encephalitis that continuously kills thousands of people annually. There is no clinical cure for rabies so far and its prevention is limited to sero-vaccinations based on standard WHO protocols. Certain compounds such as snake venoms contain active biological components with tendency toward acetylcholine receptors and ion channels at the cell surface. These compounds then are able to reduce aggregation of the virus in neuromuscular junction that may lead to inhibit the virus activity. In this study we worked on cytotoxicity and antiviral activity effects of Naja naja oxiana (Iranian Caspian cobra) snake venom components, on Rabies Lyssavirus (Rabies virus; RABV) infected mammalian cells. The concentration of 25 µg/ml F5 fraction separated by FPLC showed minor toxicity on BHK-21 cells by MTT test and high antiviral activity against infected cells by FAT assay. Further studies on F5 fractionation by HPLC showed that the proliferation of infected BHK-21 cells by rabies virus CVS-11 strain was decreased up to 80% by using 20 µg/ml P5 peak, after 48 h. We assume that P5-peptide (MW < 10 kDa) enters the cells through AChR receptors same as rabies virus without competition in binding to the cell receptors and is able to reduce the virus proliferation on post viral infection phase. This is the first report of the presence of an anti-rabies effect of Caspian cobra snake venom component. As per our results the P5 peak is a suitable candidate for further studies as a new agent to reduce CVS-11 rabies virus.
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Venenos Elapídicos/uso terapêutico , Naja naja , Raiva/tratamento farmacológico , Animais , Irã (Geográfico) , Venenos de SerpentesRESUMO
Rabies is still threatening half of the world's population with the global burden of canine rabies being estimated as 59,000 human deaths, annually. With no cure existing for clinical rabies, post-exposure prophylaxis (PEP) is the only certain means to save lives of the exposed people. In Iran, bite incidences exceed 180,000 per year, where all victims receive 5 vaccine doses for PEP, conforming to the Essen regimen. More than two-thirds of the exposed individuals stop receiving treatments after day 7, for the reason of being exposed to a non-rabid dog or cat. According to the national standard protocols, these individuals should re-start a complete 5-dose PEP course upon the re-exposure. New WHO recommendations based on scientific data is encouraging revisions to the existing prophylaxis programs. In order to know if an incomplete Essen regimen can provide adequate immunity, in the present study, 5 groups of individuals who had only received 3 first doses of the Essen regimen within the previous 1, 3, 6, 12 and 24 months were examined for immunity against rabies. Our results indicated sufficient anti-rabies neutralizing antibody in all individuals, before and after receiving two standard booster doses (i.e. days 0 and 3). This might also suggest the adequacy of the 3 first doses of vaccination, as a one-week long post-exposure vaccination program.
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Anticorpos Antivirais/sangue , Profilaxia Pós-Exposição , Vacina Antirrábica/administração & dosagem , Raiva/prevenção & controle , Soroconversão , Adulto , Idoso , Animais , Anticorpos Neutralizantes/sangue , Mordeduras e Picadas , Gatos , Cães , Humanos , Imunização Secundária , Injeções Intramusculares , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Raiva/imunologia , Vacina Antirrábica/imunologia , Adulto JovemRESUMO
INTRODUCTION: The role of laboratory parameters in screening of COVID-19 cases has not been definitely established. This study aimed to evaluate the accuracy of laboratory parameters in predicting cases with positive RT-PCR for COVID-19. METHODS: This diagnostic accuracy study was conducted on suspected COVID-19 patients, who presented to Behpooyan Clinic Medical center in Tehran (Iran) from 22 February to 14 March, 2020. Patients were divided into two groups based on the results of real time reverse transcriptase-polymerase chain reaction (RT-PCR) for COVID-19, and the accuracy of different laboratory parameters in predicting cases with positive RT-PCR was evaluated using area under the ROC curve (AUC). RESULTS: Two hundred cases with the mean age of 41.3± 14.6 (range: 19-78) years were studied (0.53% male). The result of RT-PCR for COVID-19 was positive in 70 (35%) cases. Patients with positive RT-PCR had significantly higher neutrophil (NEU) count (p = 0.0001), and C-reactive protein (CRP) (p = 0.04), lactate dehydrogenase (LDH) (p = 0.0001), aspartate aminotransferase (AST) (p = 0.001), alanine aminotransferase (ALT) (p = 0.0001), and Urea (p = 0.001) levels in serum. In addition, patients with positive RT-PCR had lower white blood cell (WBC) count (p = 0.0001) and serum albumin level (p = 0.0001) compared to others. ALT (AUC = 0.879), CRP (AUC = 0.870), NEU (AUC = 0.858), LDH (AUC = 0.835), and Urea (AUC = 0.835) had very good accuracy in predicting cases with positive RT-PCR for COVID-19, respectively. CONCLUSION: Our findings suggest that level of LDH, CRP, ALT and NEU can be used to predict the result of COVID-19 test. They can help in detection of COVID-19 patients.
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Rabies is a neurotropic virus that causes a life threatening acute viral encephalitis. The complex relationship of rabies virus (RV) with the host leads to its replication and spreading toward the neural network, where viral pathogenic effects appeared as neuronal dysfunction. In order to better understand the molecular basis of this relationship, a proteomics study on baby hamster kidney cells infected with challenge virus standard strain of RV was performed. This cell line is an in vitro model for rabies infection and is commonly used for viral seed preparation. The direct effect of the virus on cellular protein machinery was investigated by 2-DE proteome mapping of infected versus control cells followed by LC-MS/MS identification. This analysis revealed significant changes in expression of 14 proteins, seven of these proteins were viral and the remaining were host proteins with different known functions: cytoskeletal (capping protein, vimentin), anti-oxidative stress (superoxide dismutase), regulatory (Stathmin), and protein synthesis (P0). Despite of limited changes appeared upon rabies infection, they present a set of interesting biochemical pathways for further investigation on viral-host interaction.
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Proteínas do Citoesqueleto/metabolismo , Proteínas/metabolismo , Proteômica/métodos , Vírus da Raiva/metabolismo , Raiva/metabolismo , Proteínas Virais/metabolismo , Animais , Linhagem Celular , Cricetinae , Eletroforese em Gel Bidimensional , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Fosfoproteínas/metabolismo , Raiva/virologia , Vírus da Raiva/patogenicidadeRESUMO
Lyssaviruses are highly neurotropic viruses associated with neuronal apoptosis. Previous observations have indicated that the matrix proteins (M) of some lyssaviruses induce strong neuronal apoptosis. However, the molecular mechanism(s) involved in this phenomenon is still unknown. We show that for Mokola virus (MOK), a lyssavirus of low pathogenicity, the M (M-MOK) targets mitochondria, disrupts the mitochondrial morphology, and induces apoptosis. Our analysis of truncated M-MOK mutants suggests that the information required for efficient mitochondrial targeting and dysfunction, as well as caspase-9 activation and apoptosis, is held between residues 46 and 110 of M-MOK. We used a yeast two-hybrid approach, a coimmunoprecipitation assay, and confocal microscopy to demonstrate that M-MOK physically associates with the subunit I of the cytochrome c (cyt-c) oxidase (CcO) of the mitochondrial respiratory chain; this is in contrast to the M of the highly pathogenic Thailand lyssavirus (M-THA). M-MOK expression induces a significant decrease in CcO activity, which is not the case with M-THA. M-MOK mutations (K77R and N81E) resulting in a similar sequence to M-THA at positions 77 and 81 annul cyt-c release and apoptosis and restore CcO activity. As expected, the reverse mutations, R77K and E81N, introduced in M-THA induce a phenotype similar to that due to M-MOK. These features indicate a novel mechanism for energy depletion during lyssavirus-induced apoptosis.
Assuntos
Apoptose , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Lyssavirus/patogenicidade , Mitocôndrias/fisiologia , Mitocôndrias/virologia , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Animais , Caspase 9/metabolismo , Linhagem Celular , Cricetinae , Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Humanos , Imunoprecipitação , Lyssavirus/genética , Camundongos , Microscopia Confocal , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Técnicas do Sistema de Duplo-Híbrido , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
OBJECTIVES: Despite all the efforts and increased knowledge of rabies, the exact mechanisms of infection and mortality from the rabies virus are not well understood. To understand the mechanisms underlying the pathogenicity of rabies virus infection, it is crucial to study the tissue that the rabies virus naturally infects in humans. METHODS: Cerebellum brain tissue from 9 human post mortem cases from Iran, who had been infected with rabies virus, were examined histopathologically and immunohistochemically to evaluate the innate immune responses against the rabies virus. RESULTS: Histopathological examination revealed inflammation of the infected cerebellum and immunohistochemical analyses showed an increased immunoreactivity of heat shock protein 70, interleukin-6, interleukin-1, tumor necrosis factor-alpha, caspase-3, caspase-9, toll-like receptor3 and toll-like receptor4 in the infected brain tissue. CONCLUSION: These results indicated the involvement of innate immunity in rabies infected human brain tissue, which may aggravate the progression of this deadly disease.
RESUMO
BACKGROUND: Rabies, as the most important zoonotic disease, is transmitted through a bite or scratch by an infected domestic or wild carnivores and bats or contact of open wound with infected saliva. The fluorescent antibody test (FAT) is the "gold standard" diagnostic method for suspected brain samples. For close monitoring of unknown encephalitis, rabies surveillance, and also the limitations for post-mortem diagnosis of rabies in human and performing fast prophylactic measures for other individuals in contact with rabid patients, ante-mortem diagnosis based on molecular methods such as real-time polymerase chain reaction (PCR) seems to be more reliable. In this study, we detected 2 positive rabid cases using SYBR Green real-time PCR for the first time in Iran. METHODS: In this study, 3 saliva samples at intervals up to 6 hours were collected from any of the nine suspected patients with nonspecific symptoms between March 2016 and March 2017. Total RNA extraction, cDNA synthesis and real-time PCR were performed along with confirmed negative and positive controls. Then, we tracked the patients for follow-up and understanding of their status. On brain samples of patients who died, FAT and MIT (mouse inoculation test) were performed to obtain definitive results. RESULTS: In this study, the patients were 4 females and 5 males, between 8 and 80 years old from different geographical areas of Iran. The ante-mortem saliva samples of 2 out of nine patients who died were positive by SYBR Green real-time PCR. Positive results of FAT test on these samples confirmed the presence of rabies virus infection in their brains and also the ante-mortem diagnosis results. CONCLUSION: The results of this study suggest that SYBR Green real-time PCR technique on saliva sample can be used as an applicable method for ante-mortem diagnosis of rabies to avoid infection of other people such as the treating medical staff or family members of the patient.