Rapamycin and ZSTK474 can have differential effects at different post‑infection time‑points regarding CVB3 replication and CVB3‑induced autophagy

SUMMARYDefinitive diagnosis of strongyloidiasis in humans is typically achieved by detection of larvae in fecal samples. However, limitations on sensitivity of parasitological methods emphasize the need for more robust diagnostic methods. The aim of this study was to compare the diagnostic value of three methods: eggs per gram of feces (EPG), coproantigen detection by enzyme linked immunosorbent assay (ELISA), and DNA detection by conventional polymerase chain reaction (PCR). The assays were performed at 0 and 5, 8, 13, 21 and 39 days post-infection (dpi) using fecal samples from experimentally infected immunocompetent and immunosuppressed rats. In immunocompetent rats, eggs were detected in feces on days 5, 8 and 13 dpi; coproantigen detection and PCR amplification were successful at all post-infection time points (5, 8, 13, 21 and 39 dpi). In immunosuppressed rats, eggs were detected at 5, 8, 13 and 21; coproantigen detection and PCR amplification were successful at all post-infection time points. In conclusion, these results suggest that coproantigen detection and PCR may be more sensitive alternatives to traditional methods such as EPG for diagnosis of Strongyloides venezuelensis infection.

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RNA-Seq Transcriptome Analysis of Peripheral Blood From Cattle Infected With Mycobacterium bovis Across an Experimental Time Course

Frontiers in Veterinary Science ◽

10.3389/fvets.2021.662002 ◽

2021 ◽

Vol 8 ◽

Author(s):

Kirsten E. McLoughlin ◽

Carolina N. Correia ◽

John A. Browne ◽

David A. Magee ◽

Nicolas C. Nalpas ◽

...

Keyword(s):

Differentially Expressed Genes ◽

Mycobacterium Bovis ◽

Peripheral Blood ◽

Post Infection ◽

Time Course ◽

De Novo ◽

Differentially Expressed Gene ◽

Differentially Expressed ◽

Infection Time ◽

Time Point

Bovine tuberculosis, caused by infection with members of the Mycobacterium tuberculosis complex, particularly Mycobacterium bovis, is a major endemic disease affecting cattle populations worldwide, despite the implementation of stringent surveillance and control programs in many countries. The development of high-throughput functional genomics technologies, including RNA sequencing, has enabled detailed analysis of the host transcriptome to M. bovis infection, particularly at the macrophage and peripheral blood level. In the present study, we have analysed the transcriptome of bovine whole peripheral blood samples collected at −1 week pre-infection and +1, +2, +6, +10, and +12 weeks post-infection time points. Differentially expressed genes were catalogued and evaluated at each post-infection time point relative to the −1 week pre-infection time point and used for the identification of putative candidate host transcriptional biomarkers for M. bovis infection. Differentially expressed gene sets were also used for examination of cellular pathways associated with the host response to M. bovis infection, construction of de novo gene interaction networks enriched for host differentially expressed genes, and time-series analyses to identify functionally important groups of genes displaying similar patterns of expression across the infection time course. A notable outcome of these analyses was identification of a 19-gene transcriptional biosignature of infection consisting of genes increased in expression across the time course from +1 week to +12 weeks post-infection.

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Riemerella anatipestifer infection in ducks induces IL-17A production, but not IL-23p19

Scientific Reports ◽

10.1038/s41598-019-49516-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Rochelle A. Flores ◽

Cherry P. Fernandez-Colorado ◽

Fahmida Afrin ◽

Paula Leona T. Cammayo ◽

Suk Kim ◽

...

Keyword(s):

Mrna Expression ◽

Proinflammatory Cytokines ◽

Post Infection ◽

Proinflammatory Cytokine ◽

Th17 Cells ◽

Critical Role ◽

Splenic Lymphocytes ◽

Expression Levels ◽

Time Points ◽

Mrna Expression Analysis

Abstract R. anatipestifer (RA) is one of the most harmful bacterial pathogens affecting the duck industry, and infection is associated with the production of proinflammatory cytokines, including IL-17A. Another proinflammatory cytokine, IL-23, is critical for the development of Th17 cells, which produce IL-17. However, IL-23 roles have not been studied in this infection. Here, we describe the identification and mRNA expression analysis of duck IL-23p19 (duIL-23p19) in splenic lymphocytes and macrophages stimulated with killed RA and in spleens of RA-infected ducks. Expression of duIL-23p19 transcript identified in this study was relatively high in livers of healthy ducks and was upregulated in mitogen-activated splenic lymphocytes as well as in splenic lymphocytes and macrophages stimulated with killed RA. In spleens of RA-infected ducks, expression levels of duIL-23p19 transcript were unchanged at all time points except on days 4 and 7 post-infection; however, duIL-17A and IL-17F expression levels were upregulated in both spleens of RA-infected ducks and splenic lymphocytes and macrophages stimulated with killed RA. In sera collected at 24 h after this infection, duIL-23p19 expression levels were unchanged, whereas IL-17A significantly upregulated. These results suggest that IL-23p19 does not play a critical role in the IL-17A response in early stages of RA-infected ducks.

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Virulence of Salmonella enterica serotype Enteritidis aflagellate and afimbriate mutants in a day-old chick model

Epidemiology and Infection ◽

10.1017/s0950268899002460 ◽

1999 ◽

Vol 122 (3) ◽

pp. 395-402 ◽

Cited By ~ 48

Author(s):

E. ALLEN-VERCOE ◽

A. R. SAYERS ◽

M. J. WOODWARD

Keyword(s):

Post Infection ◽

Salmonella Enterica ◽

Flagellar Apparatus ◽

Infection Model ◽

Wild Type ◽

Time Points ◽

Genetic Potential ◽

Serovar Typhimurium ◽

Number Of Bacteria

Certain fimbriae and the flagellae of Salmonella enterica serovar Typhimurium have been shown to contribute to attachment and invasion of gut epithelium in the murine typhoid infection model and to contribute to pathogenesis in the chick. However, little is known of the role these organelles play in Enteritidis poultry infections and, to study this, day-old chicks were dosed orally in separate experiments with defined multiply afimbriate and/or aflagellate mutant strains of Enteritidis. The colonization and invasion characteristics of each mutant were compared with those of the isogenic wild type strain by the determination of the number of bacteria recovered from livers and spleens at known time points post infection. Compared with wild type Enteritidis, a mutant unable to express flagella but retaining the genetic potential to express fimbriae was recovered post mortem from livers and spleens in significantly reduced numbers compared to the isogenic wild-type at all time points post infection (P<0·001). Conversely, a flagellate but multiply afimbriate mutant (defective for the elaboration of five different fimbrial types) and a flagellate but non-motile ‘paralysed’ mutant were recovered from livers and spleens in similar numbers to the wild-type. The data suggested that Enteritidis flagella, but not fimbriae, played an important role in pathogenesis in the chick model and that the flagellar apparatus itself and not motility per se contributed significantly to this role.

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Functional expression of TrpC1: a human homologue of the Drosophila Trp channel

Biochemical Journal ◽

10.1042/bj3310331 ◽

1998 ◽

Vol 331 (1) ◽

pp. 331-339 ◽

Cited By ~ 76

Author(s):

William G. SINKINS ◽

Mark ESTACION ◽

William P. SCHILLING

Keyword(s):

Post Infection ◽

Mammalian Cells ◽

Expression System ◽

Baculovirus Expression System ◽

Functional Expression ◽

Sf9 Cells ◽

Infection Time ◽

A Subunit ◽

High Concentrations ◽

Inwardly Rectifying

TrpC1 appears to be a store-operated channel (SOC) when expressed in mammalian cells. In the present study, TrpC1 was expressed in Sf9 insect cells using the baculovirus expression system. Expression of TrpC1 caused an increase in basal cytosolic free Ca2+ concentration ([Ca2+]i) as a function of post-infection time. Basal Ba2+ influx, an index of plasmalemmal Ca2+ permeability, was also increased and was blocked by La3+. Although the thapsigargin-induced change in [Ca2+]i was greater in TrpC1-expressing cells than controls, Ba2+ influx was unaffected by thapsigargin. Whole-cell membrane currents recorded in TrpC1-expressing cells increased as a function of post-infection time and were (1) inwardly rectifying in symmetrical sodium gluconate solutions, (2) non-selective with respect to Na+, Ca2+ and Ba2+, and (3) blocked by La3+. Furthermore TrpC1 currents were unaffected by (1) thapsigargin, (2) dialysis of the cell with Ins(1,4,5)P3 or (3) dialysis of the cell with solutions containing high concentrations of the Ca2+ chelator, EGTA. These results suggest that TrpC1 forms non-selective cation channels that are constitutively active when expressed in Sf9 cells, but insensitive to depletion of the internal Ca2+ stores. Thus TrpC1 may be a subunit of a SOC which alone can form functional channels in Sf9 cells, but which requires additional subunits or cytoplasmic factors present in mammalian cells for expression of SOC activity.

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Analysis of Transmission Routes of Hepatitis C Virus Based on Virus Genotyping in 341 Cases with Different Suspected Initial Infection Time Points in Hunan Province, China

Medical Science Monitor ◽

10.12659/msm.907424 ◽

2018 ◽

Vol 24 ◽

pp. 5232-5241 ◽

Cited By ~ 1

Author(s):

Jian-Hua Lei ◽

Jun Liang ◽

Xing Gong ◽

Xin-Qiang Xiao ◽

Zi Chen ◽

...

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

Hunan Province ◽

Initial Infection ◽

Infection Time ◽

Time Points

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T-DNA integration is rapid and influenced by the chromatin state of the host genome

10.1101/104372 ◽

2017 ◽

Author(s):

Shay Shilo ◽

Pooja Tripathi ◽

Cathy Melamed-Bessudo ◽

Oren Tzfadia ◽

Theodore R. Muth ◽

...

Keyword(s):

Agrobacterium Tumefaciens ◽

High Throughput ◽

Post Infection ◽

Nucleosome Occupancy ◽

Plant Genome ◽

Epigenetic Landscape ◽

Dna Integration ◽

Time Points ◽

Genome Manipulation ◽

Border Sequence

AbstractAgrobacterium tumefaciens mediated T-DNA integration is a common tool for plant genome manipulation. However, there is controversy regarding whether T-DNA integration is biased towards genes or randomly distributed throughout the genome. In order to address this question, we performed high-throughput mapping of T-DNA-genome junctions obtained in the absence of selection at several time points after infection. T-DNA-genome junctions were detected as early as 6 hours post-infection. T-DNA distribution was apparently uniform throughout the chromosomes, yet local biases toward AT-rich motifs and T-DNA border sequence micro-homology were detected. Analysis of the epigenetic landscape of integration showed that selected events reported on previously were associated with extremely low methylation and nucleosome occupancy. Conversely, non-selected events from this study showed chromatin marks, such as high nucleosome occupancy and high H3K27me3 that correspond to 3D-interacting heterochromatin islands embedded within euchromatin. Such structures might play a role in capturing and silencing invading T-DNA.

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Adjusting for time of infection or positive test when estimating the risk of a post-infection outcome in an epidemic

10.1101/2021.08.13.21262014 ◽

2021 ◽

Author(s):

Shaun R Seaman ◽

Tommy Nyberg ◽

Christopher E Overton ◽

David Pascall ◽

Anne M Presanis ◽

...

Keyword(s):

Post Infection ◽

Positive Test ◽

Test Time ◽

Binary Outcome ◽

Calendar Time ◽

Infection Time ◽

Time Of Infection ◽

Infectious Pathogen ◽

Mean Time ◽

Risk Ratios

When comparing the risk of a post-infection binary outcome, e.g. hospitalisation, for two variants of an infectious pathogen, it is important to adjust for calendar time of infection to avoid the confounding that would occur if the relative incidence of the two variants and the variant-specific risks of the outcome both change over time. Infection time is typically unknown and time of positive test used instead. Likewise, time of positive test may be used instead of infection time when assessing how the risk of the binary outcome changes over calendar time. Here we show that if mean time from infection to positive test is correlated with the outcome, the risk conditional on positive test time depends on whether incidence of infection is increasing or decreasing over calendar time. This complicates interpretation of risk ratios adjusted for positive test time. We also propose a simple sensitivity analysis that indicates how these risk ratios may differ from the risk ratios adjusted for infection time.

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A comparison of PCR and ELISA methods to detect different stages of Plasmodium vivax in Anopheles arabiensis

Parasites & Vectors ◽

10.1186/s13071-021-04976-z ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Allison L. Hendershot ◽

Endashaw Esayas ◽

Alice C. Sutcliffe ◽

Seth R. Irish ◽

Endalamaw Gadisa ◽

...

Keyword(s):

Plasmodium Vivax ◽

Post Infection ◽

Anopheles Arabiensis ◽

Life Stage ◽

Time Points ◽

Malaria Epidemiology ◽

Highly Sensitive ◽

Pcr Method ◽

Infection Stage ◽

Method Agreement

Abstract Background In characterizing malaria epidemiology, measuring mosquito infectiousness informs the entomological inoculation rate, an important metric of malaria transmission. PCR-based methods have been touted as more sensitive than the current “gold-standard” circumsporozoite (CSP) ELISA. Wider application of PCR-based methods has been limited by lack of specificity for the infectious sporozoite stage. We compared a PCR method for detecting the parasite’s mitochondrial (mt) cytochrome oxidase I (COX-I) gene with ELISA for detecting circumsporozoite protein for identification of different life stages of the parasite during development within a mosquito. Methods A PCR-based method targeting the Plasmodium mt COX-I gene was compared with the CSP ELISA method to assess infectivity in Anopheles arabiensis colony mosquitoes fed on blood from patients infected with Plasmodium vivax. Mosquitoes were tested at six post-infection time points (days 0.5, 1, 6, 9, 12, 15). The head and thorax and the abdomen for each specimen were tested separately with each method. Agreement between methods at each infection stage was measured using Cohen’s kappa measure of test association. Results Infection status of mosquitoes was assessed in approximately 90 head/thorax and 90 abdomen segments at each time point; in total, 538 head/thorax and 534 abdomen segments were tested. In mosquitoes bisected after 0.5, 1, and 6 days post-infection (dpi), the mt COX-I PCR detected Plasmodium DNA in both the abdomen (88, 78, and 67%, respectively) and head/thorax segments (69, 60, and 44%, respectively), whilst CSP ELISA detected sporozoites in only one abdomen on day 6 post-infection. PCR was also more sensitive than ELISA for detection of Plasmodium in mosquitoes bisected after 9, 12, and 15 dpi in both the head and thorax and abdomen. There was fair agreement between methods for time points 9–15 dpi (κ = 0.312, 95% CI: 0.230–0.394). Conclusions The mt COX-I PCR is a highly sensitive, robust method for detecting Plasmodium DNA in mosquitoes, but its limited Plasmodium life-stage specificity cannot be overcome by bisection of the head and thorax from the abdomen prior to PCR. Thus, the mt COX-I PCR is a poor candidate for identifying infectious mosquitoes. Graphical Abstract

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The differential effects of isoflurane and sevoflurane on neonatal mice

Scientific Reports ◽

10.1038/s41598-020-76147-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Shuai Zhao ◽

Ziqi Fan ◽

Jing Hu ◽

Yueli Zhu ◽

Caixiu Lin ◽

...

Keyword(s):

Synaptic Transmission ◽

Neuronal Apoptosis ◽

Volatile Anesthetics ◽

Synaptic Function ◽

Relative Impact ◽

Differential Effects ◽

Time Points ◽

Neonatal Mice ◽

Isoflurane Group ◽

Old Mice

Abstract Previous research has shown that exposure to volatile anesthetics can induce acute neuroinflammation and neuroapoptopsis in neonatal rodents and that these events can lead to cognitive dysfunction at later stages. Isoflurane and sevoflurane are two of the most popular anesthetics used in the field of pediatrics. However, the relative impact of these two anesthetics on the developing brain at distinct time points after the induction of anesthesia has not been compared. In the present study, we exposed 7-day-old mice to clinically equivalent doses of isoflurane (1.5%) and sevoflurane (2.5%) for 4 h and then investigated consequential changes in the brains of these mice at six different time points. We analyzed the levels of proteins that are directly related to neuroapoptosis, neuroinflammation, synaptic function, and memory, in the brains of neonatal mice. Exposure of neonatal mice to isoflurane and sevoflurane resulted in acute neuronal apoptosis. Our analysis observed significant levels of neuroinflammation and changes in the expression levels of proteins associated with both synaptic transmission and memory in mice from the isoflurane group but not the sevoflurane group. Our results therefore indicate that isoflurane and sevoflurane induce differential effects in the brains of neonatal mice.

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