scholarly journals Extraintestinal Spread and Replication of a Homologous EC Rotavirus Strain and a Heterologous Rhesus Rotavirus in BALB/c Mice

2006 ◽  
Vol 80 (11) ◽  
pp. 5219-5232 ◽  
Author(s):  
M. Fenaux ◽  
M. A. Cuadras ◽  
N. Feng ◽  
M. Jaimes ◽  
H. B. Greenberg
Keyword(s):  
Nonstructural Protein ◽  
Natural Infection ◽  
Mesenteric Lymph Nodes ◽  
Newborn Mice ◽  
Rotavirus Infection ◽  
Rotavirus A ◽  
Reverse Transcription Pcr ◽  
Copy Numbers ◽  
The Central Nervous System ◽  
Nasal Secretions

ABSTRACT Although rotavirus infection has generally been felt to be restricted to the gastrointestinal tract, over the last two decades there have been sporadic reports of children with acute or fatal cases of rotavirus gastroenteritis testing positive for rotavirus antigen and/or nucleic acid in various extraintestinal locations such as serum, liver, kidney, bladder, testes, nasal secretions, cerebrospinal fluid, and the central nervous system. Recently, studies in animals and people have demonstrated that rotavirus antigenemia is a common event during natural infection. In this study, we extend these observations and compare the intestinal and extraintestinal spread of wild-type homologous murine rotavirus EC and a heterologous strain, rhesus rotavirus (RRV), in newborn mice. A strand-specific quantitative reverse transcription-PCR (ssQRT-PCR) assay was used to quantify the ability of different rotavirus strains to spread and replicate extraintestinally. Both strain EC and RRV were detected extraintestinally in the mesenteric lymph nodes (MLN), livers, lungs, blood, and kidneys. Extraintestinal replication, as measured by ssQRT-PCR, was most prominent in the MLN and occurred to a lesser degree in the livers, kidneys, and lungs. In the MLN, strain EC and RRV had similar (P < 0.05) RNA copy numbers, although EC was present at a 10,000-fold excess over RRV in the small intestine. Rotavirus nonstructural protein 4 (NSP4) and/or assembled triple-layered particles, indicated by immunostaining with the VP7 conformation-dependent monoclonal antibody 159, were detected in the MLN, lungs, and livers of EC- and RRV-inoculated mice, confirming the ssQRT-PCR findings. Infectious RRV was detected in the MLN in quantities exceeding the amount present in the small intestines or blood. The cells in the MLN that supported rotavirus replication included dendritic cells and potentially B cells and macrophages. These data indicate that extraintestinal spread and replication occurs commonly during homologous and some heterologous rotaviral infections; that the substantial host range restrictions for rhesus rotavirus, a heterologous strain present in the intestine, are not necessarily apparent at systemic sites; that the level and location of extraintestinal replication varies between strains; that replication can occur in several leukocytes subsets; and that extraintestinal replication is likely a part of the normal pathogenic sequence of homologous rotavirus infection.

scholarly journals Mitochondrial DNA Heteroplasmy as an Informational Reservoir Dynamically Linked to Metabolic and Immunological Processes Associated with COVID-19 Neurological Disorders

2021 ◽  
Author(s):  
George B. Stefano ◽  
Richard M. Kream
Keyword(s):  
Mitochondrial Dna ◽  
Mitochondrial Function ◽  
Neurological Disorders ◽  
Nuclear Dna ◽  
Mitochondrial Dynamics ◽  
Cell Types ◽  
Tissue Specific ◽  
Copy Numbers ◽  
The Central Nervous System ◽  
Mitochondrial Dna Heteroplasmy

AbstractMitochondrial DNA (mtDNA) heteroplasmy is the dynamically determined co-expression of wild type (WT) inherited polymorphisms and collective time-dependent somatic mutations within individual mtDNA genomes. The temporal expression and distribution of cell-specific and tissue-specific mtDNA heteroplasmy in healthy individuals may be functionally associated with intracellular mitochondrial signaling pathways and nuclear DNA gene expression. The maintenance of endogenously regulated tissue-specific copy numbers of heteroplasmic mtDNA may represent a sensitive biomarker of homeostasis of mitochondrial dynamics, metabolic integrity, and immune competence. Myeloid cells, monocytes, macrophages, and antigen-presenting dendritic cells undergo programmed changes in mitochondrial metabolism according to innate and adaptive immunological processes. In the central nervous system (CNS), the polarization of activated microglial cells is dependent on strategically programmed changes in mitochondrial function. Therefore, variations in heteroplasmic mtDNA copy numbers may have functional consequences in metabolically competent mitochondria in innate and adaptive immune processes involving the CNS. Recently, altered mitochondrial function has been demonstrated in the progression of coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Accordingly, our review is organized to present convergent lines of empirical evidence that potentially link expression of mtDNA heteroplasmy by functionally interactive CNS cell types to the extent and severity of acute and chronic post-COVID-19 neurological disorders.

scholarly journals Identification of Mycobacterium genavense natural infection in a domestic ferret

2018 ◽  
Vol 31 (1) ◽  
pp. 133-136 ◽  
Author(s):  
Bérengère Dequéant ◽  
Quentin Pascal ◽  
Héloïse Bilbault ◽  
Elie Dagher ◽  
Maria-Laura Boschiroli ◽  
...  
Keyword(s):  
Natural Infection ◽  
Abdominal Ultrasound ◽  
Needle Aspiration ◽  
Mesenteric Lymph Nodes ◽  
Mustela Putorius ◽  
Tissue Samples ◽  
Acid Fast Bacilli ◽  
Mycobacterium Genavense ◽  
History Of ◽  
Progressive Weight Loss

A 6-y-old neutered male ferret ( Mustela putorius furo) was presented because of a 1-mo history of progressive weight loss, chronic cough, and hair loss. On clinical examination, the animal was coughing, slightly depressed, moderately hypothermic, and had bilateral epiphora. Thoracic radiography was suggestive of severe multinodular interstitial pneumonia. Abdominal ultrasound examination revealed hepatosplenomegaly and mesenteric and pancreaticoduodenal lymphadenopathy. Fine-needle aspiration of the pancreaticoduodenal lymph node, followed by routine Romanowsky and Ziehl–Neelsen stains, revealed numerous macrophages containing myriad acid-fast bacilli, leading to identification of mycobacteriosis. Autopsy and histologic examination confirmed the presence of disseminated, poorly defined, acid-fast, bacilli-rich granulomas in the pancreaticoduodenal and mesenteric lymph nodes, intestines, and lungs. Destaining of May-Grünwald/Giemsa–stained slides with alcohol, and then restaining with Ziehl–Neelsen, revealed acid-fast rods and avoided repeat tissue sampling without affecting the Ziehl–Neelsen stain quality and cytologic features. Tissue samples were submitted for a PCR assay targeting the heat shock protein gene ( hsp65) and revealed 100% homology with Mycobacterium genavense. We emphasize the use of special stains and PCR for identification of this potential zoonotic agent.

scholarly journals Reovirus Neurotropism and Virulence Are Dictated by Sequences in the Head Domain of the Viral Attachment Protein

2018 ◽  
Vol 92 (23) ◽  
Author(s):  
Danica M. Sutherland ◽  
Pavithra Aravamudhan ◽  
Melanie H. Dietrich ◽  
Thilo Stehle ◽  
Terence S. Dermody
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Ependymal Cells ◽  
Attachment Protein ◽  
Newborn Mice ◽  
Viral Attachment ◽  
Head Domain ◽  
Serotype 1 ◽  
The Central Nervous System ◽  
The Brain

ABSTRACTViral capsid components that bind cellular receptors mediate critical functions in viral tropism and disease pathogenesis. Mammalian orthoreoviruses (reoviruses) spread systemically in newborn mice to cause serotype-specific disease in the central nervous system (CNS). Serotype 1 (T1) reovirus infects ependymal cells to cause nonlethal hydrocephalus, whereas serotype 3 (T3) reovirus infects neurons to cause fulminant and lethal encephalitis. This serotype-dependent difference in tropism and concomitant disease is attributed to the σ1 viral attachment protein, which is composed of head, body, and tail domains. To identify σ1 sequences that contribute to tropism for specific cell types in the CNS, we engineered a panel of viruses expressing chimeric σ1 proteins in which discrete σ1 domains have been reciprocally exchanged. Parental and chimeric σ1 viruses were compared for replication, tropism, and disease induction following intracranial inoculation of newborn mice. Viruses expressing T1 σ1 head sequences infect the ependyma, produce relatively lower titers in the brain, and do not cause significant disease. In contrast, viruses expressing T3 σ1 head sequences efficiently infect neurons, replicate to relatively higher titers in the brain, and cause a lethal encephalitis. Additionally, T3 σ1 head-expressing viruses display enhanced infectivity of cultured primary cortical neurons compared with T1 σ1 head-expressing viruses. These results indicate that T3 σ1 head domain sequences promote infection of neurons, likely by interaction with a neuron-specific receptor, and dictate tropism in the CNS and induction of encephalitis.IMPORTANCEViral encephalitis is a serious and often life-threatening inflammation of the brain. Mammalian orthoreoviruses are promising oncolytic therapeutics for humans but establish virulent, serotype-dependent disease in the central nervous system (CNS) of many young mammals. Serotype 1 reoviruses infect ependymal cells and produce hydrocephalus, whereas serotype 3 reoviruses infect neurons and cause encephalitis. Reovirus neurotropism is hypothesized to be dictated by the filamentous σ1 viral attachment protein. However, it is not apparent how this protein mediates disease. We discovered that sequences forming the most virion-distal domain of T1 and T3 σ1 coordinate infection of either ependyma or neurons, respectively, leading to mutually exclusive patterns of tropism and disease in the CNS. These studies contribute new knowledge about how reoviruses target cells for infection in the brain and inform the rational design of improved oncolytic therapies to mitigate difficult-to-treat tumors of the CNS.

Pathology of Angiostrongylus cantonensis infection in two model avian hosts

Parasitology ◽  
2020 ◽  
pp. 1-4
Author(s):  
Barbora Fecková ◽  
Priyanka Djoehana ◽  
Barbora Putnová ◽  
Michaela Valašťanová ◽  
Michaela Petríková ◽  
...  
Keyword(s):  
Low Dose ◽  
Natural Infection ◽  
Clinical Signs ◽  
French Polynesia ◽  
Angiostrongylus Cantonensis ◽  
High Dose ◽  
Wide Range ◽  
The Central Nervous System ◽  
Gross Lesions ◽  
Natural Pest Control

Abstract Angiostrongylus cantonensis causes severe neurological disorders in a wide range of warm-blooded animals, including several avian species. A laboratory isolate of A. cantonensis originating from French Polynesia, genotyped as clade 2, was used to assess the effect of experimental infection in chicken and Japanese quail. Low dose groups of birds were infected orally by 100 L3 larvae, high dose groups by 1500 L3 larvae and the birds in the third group were fed three infected snails, mimicking a natural infection. Clinical signs during the first week after infection, haematology, biochemistry, gross lesions and histology findings were used to assess the pathology of the infection. Some of the infected birds showed peripheral eosinophilia, while mild neurological signs were seen in others. No larvae were observed in serial sections of the central nervous system of infected birds 1 week after infection and no major gross lesions were observed during necropsy; histopathology did not reveal lesions directly attributable to A. cantonensis infection. Our results suggest that galliform birds are not highly susceptible to A. cantonensis infection and open a question of the importance of Galliformes in endemic areas as natural pest control, lowering the number of hosts carrying the infective larvae.

scholarly journals Reference Human Rotavirus A Genome Sequence from a Previously Vaccinated Child with Diarrhea in Nigeria

2020 ◽  
Vol 9 (5) ◽  
Author(s):  
T. O. C. Faleye ◽  
U. E. George ◽  
C. Simsek ◽  
O. A. Arowolo ◽  
O. M. Adewumi ◽  
...  
Keyword(s):  
Genome Sequence ◽  
Reverse Transcription ◽  
Rapid Test ◽  
Etiologic Agent ◽  
Rt Pcr ◽  
Rotavirus A ◽  
Reverse Transcription Pcr ◽  
Human Rotavirus ◽  
A Genome ◽  
Genotype Constellation

In 2018, a 26-month-old girl, fully vaccinated with Rotarix in 2016, presented with fever, diarrhea, and vomiting. A rapid test showed that her feces contained rotavirus A (RVA). VP7 reverse transcription-PCR (RT-PCR) and Illumina sequencing showed that a G1P[8] strain with a Wa-like genotype constellation was the etiologic agent. This is the first near-complete RVA genome sequence from Nigeria.

scholarly journals Rotavirus NSP1 Associates with Components of the Cullin RING Ligase Family of E3 Ubiquitin Ligases

2016 ◽  
Vol 90 (13) ◽  
pp. 6036-6048 ◽  
Author(s):  
Lindy M. Lutz ◽  
Chandler R. Pace ◽  
Michelle M. Arnold
Keyword(s):  
Mass Spectrometry ◽  
Ubiquitin Ligase ◽  
Nonstructural Protein ◽  
Ubiquitin Proteasome System ◽  
Scaffolding Proteins ◽  
Target Proteins ◽  
Rotavirus A ◽  
Ubiquitin Proteasome ◽  
Infected Cells

ABSTRACTThe rotavirus nonstructural protein NSP1 acts as an antagonist of the host antiviral response by inducing degradation of key proteins required to activate interferon (IFN) production. Protein degradation induced by NSP1 is dependent on the proteasome, and the presence of a RING domain near the N terminus has led to the hypothesis that NSP1 is an E3 ubiquitin ligase. To examine this hypothesis, pulldown assays were performed, followed by mass spectrometry to identify components of the host ubiquitination machinery that associate with NSP1. Multiple components of cullin RING ligases (CRLs), which are essential multisubunit ubiquitination complexes, were identified in association with NSP1. The mass spectrometry was validated in both transfected and infected cells to show that the NSP1 proteins from different strains of rotavirus associated with key components of CRL complexes, most notably the cullin scaffolding proteins Cul3 and Cul1.In vitrobinding assays using purified proteins confirmed that NSP1 specifically interacted with Cul3 and that the N-terminal region of Cul3 was responsible for binding to NSP1. To test if NSP1 used CRL3 to induce degradation of the target protein IRF3 or β-TrCP, Cul3 levels were knocked down using a small interfering RNA (siRNA) approach. Unexpectedly, loss of Cul3 did not rescue IRF3 or β-TrCP from degradation in infected cells. The results indicate that, rather than actively using CRL complexes to induce degradation of target proteins required for IFN production, NSP1 may use cullin-containing complexes to prevent another cellular activity.IMPORTANCEThe ubiquitin-proteasome pathway plays an important regulatory role in numerous cellular functions, and many viruses have evolved mechanisms to exploit or manipulate this pathway to enhance replication and spread. Rotavirus, a major cause of severe gastroenteritis in young children that causes approximately 420,000 deaths worldwide each year, utilizes the ubiquitin-proteasome system to subvert the host innate immune response by inducing the degradation of key components required for the production of interferon (IFN). Here, we show that NSP1 proteins from different rotavirus strains associate with the scaffolding proteins Cul1 and Cul3 of CRL ubiquitin ligase complexes. Nonetheless, knockdown of Cul1 and Cul3 suggests that NSP1 induces the degradation of some target proteins independently of its association with CRL complexes, stressing a need to further investigate the mechanistic details of how NSP1 subverts the host IFN response.

scholarly journals EXPERIMENTAL INFECTION OF THE CHICK EMBRYO WITH THE VIRUS OF PSEUDORABIES

1942 ◽  
Vol 76 (3) ◽  
pp. 263-270 ◽  
Author(s):  
Frederik B. Bang
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Chick Embryo ◽  
Experimental Infection ◽  
Natural Infection ◽  
Hyperimmune Serum ◽  
Disease Pattern ◽  
The Central Nervous System ◽  
Hemorrhagic Tendency ◽  
The Brain

The chick embryo responds to experimental infection with the virus of pseudorabies with a disease pattern simulating the natural infection. Virus lesions of the membrane are followed by infection of all tissues of the central nervous system. Fixed strains produce a hemorrhagic destruction of the central nervous system of the embryo, which is referable to destruction of blood vessel endothelium. Field strains lack the hemorrhagic tendency, but infect the brain when inoculated on the membrane. Neutralization of the virus by specific hyperimmune serum can be demonstrated by inoculation on the membrane. The reaction of the embryo to the virus varies with the age of the embryo. This is reflected both in the membranal lesion and in the subsequent encephalitis.

scholarly journals High prevalence of circulating DS-1-like human rotavirus A and genotype diversity in children with acute gastroenteritis in Thailand from 2016 to 2019

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10954
Author(s):  
Siripat Pasittungkul ◽  
Fajar Budi Lestari ◽  
Jiratchaya Puenpa ◽  
Watchaporn Chuchaona ◽  
Nawarat Posuwan ◽  
...  
Keyword(s):  
Acute Gastroenteritis ◽  
Public Health Problem ◽  
Major Public Health Problem ◽  
Viral Gastroenteritis ◽  
Seasonal Incidence ◽  
Rotavirus Infection ◽  
Rotavirus A ◽  
Human Rotavirus ◽  
Genotype Diversity ◽  
Stool Samples

Background Human rotavirus A (RVA) infection is the primary cause of acute gastroenteritis (AGE) in infants and young children worldwide, especially in children under 5 years of age and is a major public health problem causing severe diarrhea in children in Thailand. This study aimed to investigate the prevalence, genotype diversity, and molecular characterization of rotavirus infection circulating in children under 15 years of age diagnosed with AGE in Thailand from January 2016 to December 2019. Methods A total of 2,001 stool samples were collected from children with gastroenteritis (neonates to children <15 years of age) and tested for RVA by real-time polymerase chain reaction (RT-PCR). Amplified products were sequenced and submitted to an online genotyping tool for analysis. Results Overall, 301 (15.0%) stool samples were positive for RVA. RVA occurred most frequently among children aged 0-24 months. The seasonal incidence of rotavirus infection occurred typically in Thailand during the winter months (December-March). The G3P[8] genotype was identified as the most prevalent genotype (33.2%, 100/301), followed by G8P[8] (10.6%, 32/301), G9P[8] (6.3%, 19/301), G2P[4] (6.0%, 18/301), and G1P[6] (5.3%, 16/301). Uncommon G and P combinations such as G9P[4], G2P[8], G3P[4] and G3P[9] were also detected at low frequencies. In terms of genetic backbone, the unusual DS-1-like G3P[8] was the most frequently detected (28.2%, 85/301), and the phylogenetic analysis demonstrated high nucleotide identity with unusual DS-1-like G3P[8] detected in Thailand and several countries. Conclusions A genetic association between RVA isolates from Thailand and other countries ought to be investigated given the local and global dissemination of rotavirus as it is crucial for controlling viral gastroenteritis, and implications for the national vaccination programs.

scholarly journals Correlation between prevalence of selected enteropathogens and diarrhea in children: a case-control study in China

2021 ◽  
Author(s):  
Zheng Huang ◽  
Zixiang He ◽  
Zhongqiu Wei ◽  
Wei Wang ◽  
Zhenpeng Li ◽  
...  
Keyword(s):  
Real Time ◽  
Clinical Significance ◽  
Detection Methods ◽  
Nucleic Acid Detection ◽  
Rotavirus A ◽  
Reverse Transcription Pcr ◽  
Polymerase Chain ◽  
Norovirus Gii ◽  
Positive Results ◽  
Control Study

Abstract Background The application of nucleic acid detection methods improves the ability of laboratories to detect diarrheal pathogens, but it also poses new challenges for the interpretation of the results. It is often difficult to attribute a diarrhea episode to the detected pathogens. Here we investigated the prevalence of 19 enteropathogens among diarrheal and non-diarrheal children and provided support for understanding the clinical significance of the pathogens. Methods A total of 710 fecal samples were collected from children under 5 years old in two different regions of China from May 2017 to March 2018, comprising 383 mild to moderate diarrheal cases and 327 non-diarrheal controls. The enteropathogens were detected using real-time polymerase chain reaction (PCR) or real-time reverse transcription PCR (RT-PCR). Results Enteropathogens were detected in 68.9% of the cases and 41.3% of the controls. Rotavirus A (adjusted OR [aOR], 9.91; 95% CI, 4.99–19.67), norovirus GI and GII (aOR, 3.82; 95% CI, 2.12–6.89), and Campylobacter jejuni (aOR, 20.12; 95% CI, 2.57–157.38) were significantly associated with diarrhea (p &lt; 0.05). Adenovirus, norovirus GII, rotavirus A, and enteroaggregative Escherichia coli (pCVD432) gave lower cycle threshold (Ct) values in the cases than in the controls (p &lt; 0.05). Rotavirus A and norovirus GII were associated with diarrhea when the Ct value were ≤ 30 and ≤ 25, respectively. Conclusions The types and loads of enteropathogens are likely to influence the interpretation of the clinical significance of positive results.

scholarly journals Culture-Based Virus Isolation To Evaluate Potential Infectivity of Clinical Specimens Tested for COVID-19

2020 ◽  
Vol 58 (8) ◽  
Author(s):  
Chung-Guei Huang ◽  
Kuo-Ming Lee ◽  
Mei-Jen Hsiao ◽  
Shu-Li Yang ◽  
Peng-Nien Huang ◽  
...  
Keyword(s):  
Real Time ◽  
Viral Genome ◽  
Copy Number ◽  
Virus Isolation ◽  
Rt Pcr ◽  
Clinical Specimens ◽  
Reverse Transcription Pcr ◽  
Copy Numbers ◽  
Genome Copy Number ◽  
Virus Culture

ABSTRACT Real-time reverse transcription-PCR (RT-PCR) is currently the most sensitive method to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19). However, the correlation between detectable viral RNA and culturable virus in clinical specimens remains unclear. Here, we performed virus culture for 60 specimens that were confirmed to be positive for SARS-CoV-2 RNA by real-time RT-PCR. The virus could be successfully isolated from 12 throat and nine nasopharyngeal swabs and two sputum specimens. The lowest copy number required for virus isolation was determined to be 5.4, 6.0, and 5.7 log10 genome copies/ml sample for detecting the nsp12, E, and N genes, respectively. We further examined the correlation of genome copy number and virus isolation in different regions of the viral genome, demonstrating that culturable specimens are characterized by high copy numbers with a linear correlation observed between copy numbers of amplicons targeting structural and nonstructural regions. Overall, these results indicate that in addition to the copy number, the integrity of the viral genome should be considered when evaluating the infectivity of clinical SARS-CoV-2 specimens.

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