Publications by authors named "Guozhong Zhang"

91 Publications

Resident bacteria contribute to opportunistic infections of the respiratory tract.

PLoS Pathog 2021 Mar 19;17(3):e1009436. Epub 2021 Mar 19.

National Center for Veterinary Drug Safety Evaluation, College of Veterinary Medicine, China Agricultural University, Beijing, China.

Opportunistic pathogens frequently cause volatile infections in hosts with compromised immune systems or a disrupted normal microbiota. The commensalism of diverse microorganisms contributes to colonization resistance, which prevents the expansion of opportunistic pathogens. Following microbiota disruption, pathogens promptly adapt to altered niches and obtain growth advantages. Nevertheless, whether and how resident bacteria modulate the growth dynamics of invasive pathogens and the eventual outcome of such infections are still unclear. Here, we utilized birds as a model animal and observed a resident bacterium exacerbating the invasion of Avibacterium paragallinarum (previously Haemophilus paragallinarum) in the respiratory tract. We first found that negligibly abundant Staphylococcus chromogenes, rather than Staphylococcus aureus, played a dominant role in Av. paragallinarum-associated infectious coryza in poultry based on epidemic investigations and in vitro analyses. Furthermore, we determined that S. chromogenes not only directly provides the necessary nutrition factor nicotinamide adenine dinucleotide (NAD+) but also accelerates its biosynthesis and release from host cells to promote the survival and growth of Av. paragallinarum. Last, we successfully intervened in Av. paragallinarum-associated infections in animal models using antibiotics that specifically target S. chromogenes. Our findings show that opportunistic pathogens can hijack commensal bacteria to initiate infection and expansion and suggest a new paradigm to ameliorate opportunistic infections by modulating the dynamics of resident bacteria.
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http://dx.doi.org/10.1371/journal.ppat.1009436DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8011790PMC
March 2021

The furin-S2' site in avian coronavirus plays a key role in central nervous system damage progression.

J Virol 2021 Mar 16. Epub 2021 Mar 16.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, People's Republic of China

The furin cleavage site plays an important role in virus pathogenicity. The spike protein of SARS-CoV-2 harbors a furin cleavage site insertion in contrast to SARS-CoV, which may be related to its stronger communicability. An avian coronavirus with an extra furin cleavage site upstream of the fusion peptide (S2' site) infected monocyte cells and neuron cells leading to viremia or encephalitis, respectively. Immunohistochemistry and real-time quantitative polymerase chain reaction were used to follow disease progression and demonstrated differences between the parent avian coronavirus and mutated avian coronavirus with a furin-S2' site. Magnetic resonance imaging and biological dye to evaluate the blood-brain barrier permeability showed that avian coronavirus with a furin-S2' site had increased permeability compared with parent avian coronavirus. Immunohistochemistry of brains after intracerebral injection of avian coronavirus and immunofluorescence staining of primary neuron cells demonstrated the furin-S2' site expanded the cell tropism of the mutant avian coronavirus to neuron cells. TNF-α, which has a key role in blood-brain barrier permeability, was highly induced by avian coronavirus with a furin-S2' site compared with the parent avian coronavirus. We demonstrated the process involved in mutant avian coronavirus-induced disease and that the addition of a furin-S2' site changed the virus cell tropism.Coronaviruses have broken out three times in two decades. Spike (S) protein plays a key role in the process of infection. To clarify importance of furin cleavage site in spike protein for coronavirus, we investigated the pathogenesis of neurotropic avian coronavirus whose spike protein contains an extra furin cleavage site (furin-S2' site). By combining real-time quantitative polymerase chain reaction and immunohistochemistry we demonstrated that infectious bronchitis virus (IBV) infects brain instead of trachea when its S protein contains furin-S2' site. Moreover, the virus was shown to increase the permeability of blood-brain barrier, infect neuron cells and induce high expression of TNF-α. Based on these results we further show that furin cleavage site in S protein plays an important role in coronavirus pathogenicity and cell tropism. Our study extends previous publications on function of S protein of coronavirus, increasing the understanding of researchers to coronavirus.
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http://dx.doi.org/10.1128/JVI.02447-20DOI Listing
March 2021

The dichotomous and incomplete adaptive immunity in COVID-19 patients with different disease severity.

Signal Transduct Target Ther 2021 03 8;6(1):113. Epub 2021 Mar 8.

Institute of Immunology, Third Military Medical University, Chongqing, China.

The adaptive immunity that protects patients from coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is not well characterized. In particular, the asymptomatic patients have been found to induce weak and transient SARS-CoV-2 antibody responses, but the underlying mechanisms remain unknown; meanwhile, the protective immunity that guide the recovery of these asymptomatic patients is elusive. Here, we characterized SARS-CoV-2-specific B-cell and T-cell responses in 10 asymptomatic patients and 64 patients with other disease severity (mild, n = 10, moderate, n = 32, severe, n = 12) and found that asymptomatic or mild symptomatic patients failed to mount virus-specific germinal center (GC) B cell responses that result in robust and prolonged humoral immunity, assessed by GC response indicators including follicular helper T (T) cell and memory B cell responses as well as serum CXCL13 levels. Alternatively, these patients mounted potent virus-specific T1 and CD8 T cell responses. In sharp contrast, patients of moderate or severe disease induced vigorous virus-specific GC B cell responses and associated T responses; however, the virus-specific T1 and CD8 T cells were minimally induced in these patients. These results, therefore, uncovered the protective immunity in asymptomatic patients and also revealed the strikingly dichotomous and incomplete humoral and cellular immune responses in COVID-19 patients with different disease severity, providing important insights into rational design of effective COVID-19 vaccines.
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http://dx.doi.org/10.1038/s41392-021-00525-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7938043PMC
March 2021

The Pathology of Morphine-Inhibited Nerve Repair and Morphine-Induced Nerve Damage Is Mediated via Endoplasmic Reticulum Stress.

Front Neurosci 2021 19;15:618190. Epub 2021 Feb 19.

Hebei Key Laboratory of Forensic Medicine, Collaborative Innovation Center of Forensic Medical Molecular Identification, College of Forensic Medicine, Hebei Medical University, Shijiazhuang, China.

Objective: The aim of the present study was to observe the pathological damage in the cerebral cortex of rats under acute morphine exposure (AME) and different durations of morphine dependence (MD), explore whether endoplasmic reticulum stress (ERS) is involved in the damage process, and assess the effect of morphine exposure on the proliferation and differentiation of newborn neurons.

Methods: Rat models of AME and different durations of MD were established. Pathological changes in cortical neurons were assessed by hematoxylin and eosin (H&E) and thionine staining. The expression of nuclear receptor-related factor 1 (NURR1) and that of the ERS-related proteins glucose-regulated protein 78 (GRP78), p-eIF2α, activating transcription factor 6 (ATF6), and CHOP in cortical neurons was assessed by immunohistochemistry. Double immunofluorescence labeling was used to observe the expression of Ki-67.

Results: H&E and thionine staining revealed that AME resulted in pyknotic changes in cortical neurons. With prolonged morphine exposure, the number of pyknotic neurons was significantly increased, the protein expression of Ki-67 and NURR1 was significantly decreased, and the protein levels of GRP78, p-eIF2α, ATF6, and CHOP showed marked dynamic changes.

Conclusion: AME and different durations of MD caused varying degrees of pathological changes in the cortex. Furthermore, the dynamic changes observed in ERS-related protein expression suggested that ERS may be associated with cortical injury. Different durations of MD inhibited the proliferation, differentiation, and migration of newborn neurons, which may affect the nerve repair process after injury.
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http://dx.doi.org/10.3389/fnins.2021.618190DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7935558PMC
February 2021

An attenuated TW-like infectious bronchitis virus strain has potential to become a candidate vaccine and S gene is responsible for its attenuation.

Vet Microbiol 2021 Mar 17;254:109014. Epub 2021 Feb 17.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China. Electronic address:

TW-like infectious bronchitis virus (IBV) with high pathogenicity is becoming the predominant IBV type circulating in China. To develop vaccines against TW-like IBV strains and investigate the critical genes associated with their virulence, GD strain was attenuated by 140 serial passages in specific-pathogen-free embryonated eggs and the safety and efficacy of the attenuated GD strain (aGD) were examined. The genome sequences of GD and aGD were also compared and the effects of mutations in the S gene were observed. The results revealed that aGD strain showed no obvious pathogenicity with superior protective efficacy against TW-like and QX-like virulent IBV strains. The genomes of strains aGD and GD shared high similarity (99.87 %) and most of the mutations occurred in S gene. Recombinant IBV strain rGD, in which the S gene was replaced with the corresponding regions from aGD, showed decreased pathogenicity compared with its parental strain. In conclusion, attenuated TW-like IBV strain aGD is a potential vaccine candidate and the S gene is responsible for its attenuation. Our research has laid the foundation for future exploration of the attenuating molecular mechanism of IBV.
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http://dx.doi.org/10.1016/j.vetmic.2021.109014DOI Listing
March 2021

A Hybrid Strategy for Patients With Complex Cerebral Aneurysm: STA-MCA Bypass in Combination With Endovascular Embolization.

Front Neurol 2020 15;11:614601. Epub 2021 Jan 15.

Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, China.

This work aims to present our experience of patients with complex cerebral aneurysm treated with a hybrid approach: superficial temporal artery-middle cerebral artery (STA-MCA) bypass in combination with endovascular exclusion of the aneurysm. Patients with aneurysms deemed unclippable and uncoilable were included. All patients were treated with a hybrid approach. After STA-MCA bypass, the parent artery was temporarily occluded. If the intraoperative motor evoked potential (MEP) and somatosensory evoked potential (SEP) waveforms remain normal and last for 30 min, the aneurysm and te parent artery will be embolized permanently with detachable balloons or coils. A total of 20 patients with 22 aneurysms were included in this study. There were 13 women and 7 men, with an average age of 42.5 years. Intraoperative angiography showed the good patency of all the STA grafts, and neither SEP nor MEP abnormalities were detected. After the parent artery and the aneurysm were occluded, the intraoperative angiography showed an immediately successful exclusion of the aneurysm in 20 aneurysms and immediate contrast stasis in two. All patients recovered uneventfully without ischemic or hemorrhagic complication. Angiography at 6-month follow-up showed the total obliteration in 20 aneurysms. Two aneurysms showed residuals and were recoiled. All STA grafts showed a good patency, and the mean graft flow was 124.2 ml/min. STA-MCA bypass in combination with endovascular exclusion is an appropriate option for patients with complex cerebral aneurysms that are not amenable to direct surgical clipping or endovascular embolization.
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http://dx.doi.org/10.3389/fneur.2020.614601DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7844085PMC
January 2021

Mechanisms and consequences of Newcastle disease virus W protein subcellular localization in the nucleus or mitochondria.

J Virol 2021 Jan 13. Epub 2021 Jan 13.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.

We previously demonstrated that W proteins from different Newcastle disease virus (NDV) strains localize in either the cytoplasm (e.g., NDV strain SG10) or the nucleus (e.g., NDV strain La Sota). To clarify the mechanism behind these cell localization differences, we overexpressed W protein derived from four different NDV strains or W protein associated with different cellular regions in Vero cells. This revealed that the key region for determining W protein localization is 180-227aa. Further experiments found that there is a nuclear export signal (NES) motif in W protein 211-224aa. W protein could be transported into the nucleus via interaction with KPNA1, KPNA2, and KPNA6 in a nuclear localization signal-dependent manner, and W protein containing an NES was transported back to the cytoplasm in a CRM1-independent manner. Interestingly, we observed that the cytoplasm-localized W protein colocalizes with mitochondria. We rescued the NES-deletion W protein NDV strain rSG10-ΔW/W using an NDV reverse genetics system and found that the replication ability, virulence, and pathogenicity of an NDV strain were all higher when the W protein cellular localization was in the nucleus rather than the mitochondria. Further experiments revealed that W protein nuclear localization reduced the expression of IFN-β otherwise stimulated by NDV. Our research reveals the mechanism by which NDV W protein becomes localized to different parts of the cell and demonstrates the outcomes of nuclear or cytoplasmic localization both and , laying a foundation for subsequent functional studies of the W protein in NDV and other paramyxoviruses. In Newcastle disease virus (NDV), the W protein, like the V protein, is a nonstructural protein encoded by the P gene via RNA editing. Compared with V protein, W protein has a common N-terminal domain but a unique C-terminal domain. V protein is known as a key virulence factor and an important interferon antagonist across the family In contrast, very little is known about the function of NDV W protein, and this limited information is based on studies of the Nipah virus W protein. Here, we investigated the localization mechanism of NDV W protein and its subcellular distribution in mitochondria. We found that W protein localization differences impact IFN-β production, consequently affecting NDV virulence, replication, and pathogenicity. This work provides new insights on the differential localization mechanism of NDV W proteins, along with fundamental knowledge for understanding the functions of W proteins in NDV and other paramyxoviruses.
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http://dx.doi.org/10.1128/JVI.02087-20DOI Listing
January 2021

A Genetic Screen Identifies Etl4-Deficiency Capable of Stabilizing the Haploidy in Embryonic Stem Cells.

Stem Cell Reports 2021 Jan;16(1):29-38

State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005, China; Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005, China. Electronic address:

Mammalian haploid embryonic stem cells (haESCs) hold great promise for functional genetic studies and forward screening. However, all established haploid cells are prone to spontaneous diploidization during long-term culture, rendering application challenging. Here, we report a genome-wide loss-of-function screening that identified gene mutations that could significantly reduce the rate of self-diploidization in haESCs. We further demonstrated that CRISPR/Cas9-mediated Etl4 knockout (KO) stabilizes the haploid state in different haESC lines. More interestingly, Etl4 deficiency increases mitochondrial oxidative phosphorylation (OXPHOS) capacity and decreases glycolysis in haESCs. Mimicking this effect by regulating the energy metabolism with drugs decreased the rate of self-diploidization. Collectively, our study identified Etl4 as a novel haploidy-related factor linked to an energy metabolism transition occurring during self-diploidization of haESCs.
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http://dx.doi.org/10.1016/j.stemcr.2020.11.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7815943PMC
January 2021

Coronavirus Endoribonuclease Ensures Efficient Viral Replication and Prevents Protein Kinase R Activation.

J Virol 2020 Dec 23. Epub 2020 Dec 23.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.

Coronavirus (CoV) nsp15 is an endoribonuclease conserved throughout the CoV family. The enzymatic activity and crystal structure of infectious bronchitis virus (IBV) nsp15 are undefined, and the protein's role in replication remains unclear. We verified the uridylate-specific endoribonuclease (EndoU) activity of IBV and found that the EndoU active sites were located in the C-terminus of nsp15 and included His223, His238, Lys278 and Tyr334. We further constructed an infectious clone of the IBV-rSD strain (rSD-wild-type [WT]) and EndoU-deficient IBVs by changing the codon for the EndoU catalytic residues to alanine. Both the rSD-WT and EndoU-deficient viruses propagated efficiently in embryonated chicken eggs. Conversely, EndoU-deficient viral propagation was severely impaired in chicken embryonic kidney cells, which was reflected in the lower viral mRNA accumulation and protein synthesis. After infecting chickens with the parental rSD-WT strain and EndoU-deficient viruses, the EndoU-deficient-virus-infected chickens presented reduced mortality, tissue injury and viral shedding. Coronaviruses can emerge from animal reservoirs into naive host species to cause pandemic respiratory and gastrointestinal diseases with significant mortality in humans and domestic animals. Infectious bronchitis virus (IBV), a γ-coronavirus, infects respiratory, renal and reproductive systems, causing millions of dollars in lost revenue worldwide annually. Mutating the viral endoribonuclease resulted in an attenuated virus and prevented protein kinase R activation. Therefore, EndoU activity is a virulence factor in IBV infections, thus providing an approach for generating live-attenuated vaccine candidates for emerging coronaviruses.
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http://dx.doi.org/10.1128/JVI.02103-20DOI Listing
December 2020

Aggressive Treatment in Glioblastoma: What Determines the Survival of Patients?

J Neurol Surg A Cent Eur Neurosurg 2021 Mar 6;82(2):112-117. Epub 2020 Nov 6.

Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, China.

Background And Study Aims:  The exact reason of long-term survival in glioblastoma (GBM) patients has remained uncertain. Molecular parameters in addition to histology to define malignant gliomas are hoped to facilitate clinical, experimental, and epidemiological studies.

Material And Methods:  A population of GBM patients with similar clinical characteristics (especially similar resectability) was reviewed to compare the molecular variables between poor (overall survival [OS] < 18 months, control cohort) and long-term survivors (overall survival > 36 months, OS-36 cohort).

Results:  Long-term GBM survivors were younger. In the OS-36 cohort, the positive rate of isocitrate dehydrogenase (IDH) mutation was very low (7.69%, 3/39) and there was no statistical difference in OS between IDH mutant and wild-type patients. The results of 1p/19q codeletions are similar. Besides, there were no significant difference in MGMT promoter methylation, telomerase reverse transcriptase (TERT) promoter mutation, and TP53 mutations between OS-36 cohort and control cohort.

Conclusions:  No distinct markers consistently have been identified in long-term survivors of GBM patients, and great importance should be attached to further understand the biological characteristics of the invasive glioma cells because of the nature of diffuse tumor permeation.
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http://dx.doi.org/10.1055/s-0040-1713172DOI Listing
March 2021

A Panel of Exosome-Derived miRNAs of Cerebrospinal Fluid for the Diagnosis of Moyamoya Disease.

Front Neurosci 2020 25;14:548278. Epub 2020 Sep 25.

Department of Laboratory Medicine, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China.

Background: Moyamoya disease (MMD) is an important cause of stroke in children and young adults in Asia. To date, diagnosis remains challenging due to varying clinical manifestations and unknown pathogenesis. The study aims to identify cerebrospinal fluid (CSF) exosomal microRNAs (exomiRs) that can serve as a novel diagnostic biomarker for diagnosis and assess its clinical applications.

Methods: CSF samples were taken from 31 MMD patients and 31 healthy controls. Initial screening of miRNA expression was performed on samples pooled from MMD patients and controls using microarray and validated using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The diagnostic accuracy of the potential exosomal miRNAs was evaluated using receiver operating characteristic curve analyses in an independent patient cohort. The potential pathways regulated by the miRNAs was also determined using bioinformatics analysis.

Results: The microarray results demonstrated that six exomiRs were dysregulated in the MMD patients compared to the controls. Using qRT-PCR, we validated four of the miRNAs (miR-3679-5p, miR-6165, miR-6760-5p, and miR-574-5p) as a biomarker for MMD diagnosis. The four exomiRs showed enhanced sensitivity (75%) and specificity (93.75%) in terms of differentiating MMD patients from healthy subjects [area under the curve (AUC) = 0.9453]. Pathway enrichment analysis for potential targets of six exomiRs identified proteins involved in cell adhesion and junction formation in the brain.

Conclusions: We identified a novel and highly sensitive exomiRs signature for MMD detection and explored its potential targets using bioinformatics analysis.
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http://dx.doi.org/10.3389/fnins.2020.548278DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7546773PMC
September 2020

Research Note: Serological investigation of Ornithobacterium rhinotracheale infection in China.

Poult Sci 2020 Oct 8;99(10):4814-4817. Epub 2020 Jul 8.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China. Electronic address:

Ornithobacterium rhinotracheale (ORT) has been associated with avian respiratory disease. On coinfection with other pathogens, ORT can cause serious health problems in avian species, leading to financial losses. To monitor the serologic prevalence of ORT in chicken flocks in China, 1,280 sera were collected to determine ORT antibodies among 64 flocks from 15 provinces of China using a commercial ELISA kit. The overall seroprevalence of ORT among the birds tested was 44.06%. In younger chickens, the serum positive rate was lower than that in older chickens, and with increased age, the serum positive rates increased. Older chickens had not only higher positive rates but also higher antibody levels. These data indicated that ORT infections were common in China. Because an ORT vaccine is currently not available, good disease management and biosecurity measures are required for effective disease control.
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http://dx.doi.org/10.1016/j.psj.2020.06.045DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7598332PMC
October 2020

Disease severity dictates SARS-CoV-2-specific neutralizing antibody responses in COVID-19.

Signal Transduct Target Ther 2020 09 2;5(1):180. Epub 2020 Sep 2.

Institute of Immunology, PLA, Third Military Medical University, 400038, Chongqing, China.

COVID-19 patients exhibit differential disease severity after SARS-CoV-2 infection. It is currently unknown as to the correlation between the magnitude of neutralizing antibody (NAb) responses and the disease severity in COVID-19 patients. In a cohort of 59 recovered patients with disease severity including severe, moderate, mild, and asymptomatic, we observed the positive correlation between serum neutralizing capacity and disease severity, in particular, the highest NAb capacity in sera from the patients with severe disease, while a lack of ability of asymptomatic patients to mount competent NAbs. Furthermore, the compositions of NAb subtypes were also different between recovered patients with severe symptoms and with mild-to-moderate symptoms. These results reveal the tremendous heterogeneity of SARS-CoV-2-specific NAb responses and their correlations to disease severity, highlighting the needs of future vaccination in COVID-19 patients recovered from asymptomatic or mild illness.
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http://dx.doi.org/10.1038/s41392-020-00301-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7464057PMC
September 2020

Replicase 1a gene plays a critical role in pathogenesis of avian coronavirus infectious bronchitis virus.

Virology 2020 11 20;550:1-7. Epub 2020 Aug 20.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China. Electronic address:

Avian coronavirus infectious bronchitis virus (IBV) is an important pathogen threatening poultry production worldwide. Here, two recombinant IBVs (rYN-1a-aYN and rYN-1b-aYN) were generated in which ORF1a or ORF1b of the virulent YN genome were replaced by the corresponding regions from the attenuated strain aYN. The pathogenicity and virulence of rIBVs were evaluated in ovo and in vivo. The results revealed that mutations in the ORF1a gene during passage in embryonated eggs caused the decreased pathogenicity of virulent IBV YN strain, proven by determination of virus replication in ECEs and CEK cells, the observation of clinical signs, gross lesions, microscopic lesions, tracheal ciliary activity and virus distribution in chickens following exposure to rIBVs. However, mutations in ORF1b had no obvious effect on virus replication in both ECEs and CEK cells, or pathogenicity in chickens. Our findings demonstrate that the replicase 1a gene of avian coronavirus IBV is a determinant of pathogenicity.
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http://dx.doi.org/10.1016/j.virol.2020.08.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7440038PMC
November 2020

Long intergenic non-protein coding RNA 00475 silencing acts as a tumor suppressor in glioma under hypoxic condition by impairing microRNA-449b-5p-dependent AGAP2 up-regulation.

Ther Adv Med Oncol 2020 11;12:1758835920940936. Epub 2020 Aug 11.

Department of Neurosurgery, Nanfang Hospital, Southern Medical University, No. 1838, North Guangzhou Avenue, Guangzhou 510515, Guangdong Province, P. R. China.

Objective: Long non-coding RNAs have been demonstrated to be involved in the progression of a variety of cancers, including glioma. Through microarray analyses, long intergenic non-protein coding RNA 00475 (LINC00475) was identified in the glioma development. However, its potential role remains incompletely understood. This study aimed to elucidate the effect of LINC00475 on the development of glioma under hypoxic conditions.

Methods: Glioma cells underwent hypoxic treatment and were collected. The functional role of LINC00475 and AGAP2 in glioma was determined using ectopic expression, depletion, and reporter assay experiments. Then, the expression of LINC00475, microRNA (miR)-449b-5p, AGAP2, FAK, and HIF-1α was determined. In addition, cell migration and invasion were examined. Finally, a tumor xenograft was carried out in nude mice to explore the role of LINC00475 on oxidation .

Results: LINC00475 was identified to be overexpressed in hypoxic glioma samples, which was further observed to bind to and down-regulate miR-449b-5p, and negatively targeted AGAP2. Moreover, we also revealed a positive correlation between LINC00475 and AGAP2 expression in glioma. In addition, silencing of LINC00475 decreased the extent of FAK phosphorylation and reduced the expression of HIF-1α and AGAP2. It was also observed that LINC00475 silencing suppressed glioma cell proliferation, migration, and invasion, and promoted cell apoptosis. Moreover, oxidation of nude mice was promoted by LINC00475 silencing.

Conclusion: Taken together, LINC00475 silencing exerted an inhibitory effect on glioma under hypoxic conditions by down-regulating AGAP2 up-regulation of miR-449b-5p.
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http://dx.doi.org/10.1177/1758835920940936DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7425262PMC
August 2020

Flow evaluation of STA-MCA bypass using quantitative ultrasonography: An alternative to standard angiography for follow up of bypass graft.

J Stroke Cerebrovasc Dis 2020 Sep 18;29(9):105000. Epub 2020 Jun 18.

Department of Neurosurgery, Nanfang Hospital, Southern Medical University, 510515 Guangzhou, Guangdong, PR China. Electronic address:

Purpose: To date, digital subtraction angiography (DSA) has been considered as the gold imaging modality for assessing graft patency after extracranial-intracranial bypass. The utility of a noninvasive and quantitative method of assessing graft flow postoperatively was evaluated by using quantitative ultrasonography.

Method: All STA-MCA bypass surgery performed over a 5-year period at a single institution were reviewed. Measured by duplex ultrasonography, pre-operative (day1) and post-operative (day1, day7, 3month and 6 month) graft blood flow rates were recorded and analyzed. Results were correlated to Matsushima grade determined by DSA performed within 24 h when ultrasonography was conducted to confirm the graft function.

Results: 100 patients with 131 operated hemispheres were included in this study. The mean flow rates in the STA graft on pre-operative day1, post-operative day 1 and 7, at 3- and 6-month postoperatively were 24.1, 106.7, 112.6, 97.4 and 79.7 ml/min respectively. The mean post-operative flow in the STA graft graded as A/B/C were significantly different (168.0 ± 34.8 ml/min, 91.0 ± 15.5, 42.1 ± 17.2 ml/min, respectively, p = 0.000). 124.5 ml/min and 65.5 ml/min are good cut-off value for predicting post-operative graft Matsushima grade. The analysis also showed excellent agreement between ultrasonography and DSA for assessing bypass function (κ = 0.78).

Conclusions: The patency of the STA grafts can be assessed noninvasively by quantitative ultrasonography, which results are comparable to those of conventional DSA. This, therefore, suggest that quantitative ultrasonography may be an alternative method to standard DSA for serial follow up of STA grafts.
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http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2020.105000DOI Listing
September 2020

Development and Application of an MRT-qPCR Assay for Detecting Coinfection of Six Vertically Transmitted or Immunosuppressive Avian Viruses.

Front Microbiol 2020 17;11:1581. Epub 2020 Jul 17.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China.

Marek's disease virus (MDV), reticuloendotheliosis virus (REV), avian reovirus (ARV), chicken infectious anemia virus (CIAV), infectious bursal disease virus (IBDV), and fowl adenovirus (FAdV) are important causes of disease in poultry. To investigate the infection status of the above six viruses in chickens in China, 1,187 samples from chicken flocks were collected and tested using a newly developed multiplex reverse-transcription quantitative real-time PCR (MRT-qPCR) assay in the study. A series of validation tests confirmed that the MRT-qPCR assay has high specificity, sensitivity, and repeatability. As for six detected pathogens, CIAV had the highest detection ratio, while ARV was not detected in any samples. In the spleen samples, the coinfection rate for MDV and CIAV was 1.6%, and that for REV and CIAV was 0.4%. In the bursa samples, the coinfection rate for FAdV and CIAV was 0.3%, and that for IBDV and CIAV was 1%. In the thymus samples, the coinfection rates for MDV and CIAV and for REV and CIAV were both 0.8%. Our study indicates that the coinfection of these viruses was existing in chickens in China. Through the detection of clinical samples, this study provides data on the coinfections of the above six pathogens and provides a basis for the further study of viral coinfection in chickens.
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http://dx.doi.org/10.3389/fmicb.2020.01581DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7379340PMC
July 2020

Pathogenic characteristics of a QX-like infectious bronchitis virus strain SD in chickens exposed at different ages and protective efficacy of combining live homologous and heterologous vaccination.

Vet Res 2020 Jul 8;51(1):86. Epub 2020 Jul 8.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian, Beijing, 100193, China.

Continued reports of infections with infectious bronchitis virus (IBV) variants have occurred since its first isolation in the 1930s. Currently, QX-like IBVs are the predominant circulating genotype around the world. Here, the pathogenicity of QX-like IBV strain SD was characterized in chickens at different ages of exposure to the virus, and the protection efficacy of available vaccine combinations against IBV was evaluated. The results revealed that QX-like IBV strain SD was severely pathogenic in chickens, causing respiratory, urinary and reproductive infections, irrespective of age, based on clinical observations, viral distribution in tissues and a ciliostasis study. Severe respiratory signs, tracheal cilia injury, nephritis and abnormal development of the oviduct and ovarian follicles were evident throughout the experiment. A challenge experiment demonstrated that the homologous QX vaccine showed superior protection efficacy compared with other available vaccines, confirming the importance of IBV vaccine seed homology against the circulating IBV strains. Our findings aid an understanding of the pathogenicity of QX-like IBVs that may help to further control the infection.
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http://dx.doi.org/10.1186/s13567-020-00811-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7341716PMC
July 2020

Rapid preparation of decellularized trachea as a 3D scaffold for organ engineering.

Int J Artif Organs 2021 Jan 25;44(1):55-64. Epub 2020 May 25.

Department of Cardiothoracic Surgery, College of Clinical Medicine, Yangzhou University, Yangzhou, China.

Objective: To shorten the preparation time of rabbit decellularized tracheal matrix through a modified detergent-enzymatic method with higher concentration of DNase (50 kU/mL), providing an experimental and theoretical basis for clinical decellularization technology.

Methods: The control group was a natural trachea, and the experimental group was a tracheal matrix subjected to two and four decellularization cycles. The performance of each group of samples was evaluated by histology and immunohistochemical staining, scanning electron microscopy, biomechanical property testing, inoculation and cytotoxicity tests, and allograft experiments.

Results: The results showed that the nuclei of the nonchondral areas of the tracheal stroma were essentially completely removed and MHC-I and MHC-II antigens were removed after two decellularization cycles. Histological staining and scanning electron microscopy showed that the extracellular matrix was retained and the basement membrane was intact. Cell inoculation and proliferation tests confirmed that the acellular tracheal matrix had good biocompatibility, and the proliferation capacity of bone mesenchymal stem cells on the matrix was increased in the experimental group compared with the control group ( < 0.05). Histological staining and CD68 molecular marker analysis after the allograft experiment showed that the inflammatory response of the acellular tracheal matrix was weak and the infiltration of surrounding macrophages was reduced.

Conclusion: A modified detergent-enzymatic method with an increased DNase (50 kU/mL) concentration requires only two cycles (4 days) to obtain a decellularized rabbit tracheal matrix with a short preparation time, good biocompatibility, suitable mechanical properties, and reduced preparation cost.
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http://dx.doi.org/10.1177/0391398820924041DOI Listing
January 2021

Characterization of ten paramyxovirus type 1 viruses isolated from pigeons in China during 1996-2019.

Vet Microbiol 2020 May 27;244:108661. Epub 2020 Mar 27.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China. Electronic address:

Pigeon paramyxovirus type 1 (PPMV-1) is an antigenic variant of avian paramyxovirus type 1, which mainly infects pigeons. Here, we characterized ten PPMV-1 viruses isolated from pigeons in China during 1996-2019. Phylogenetic analysis of available complete genomes, F and HN genes of PPMV-1 from China showed that multiple PPMV-1 genotypes (I, II, VI, and VII) exist in pigeons in China. Ten PPMV-1 viruses isolated in this study belonged to genotypes VI.1.2.2.2, VI.2.1.1.2.1, VI.2.1.1.2.2 and VII respectively. Genotype VI is predominant in pigeons. VI.2.1.1.2.2 contains most recently isolated PPMV-1 viruses, suggesting that VI.2.1.1.2.2 is a prevalent genotype in pigeons in China. In vitro and in vivo studies showed that four representative viruses from genotypes VI.2.1.1.2.1 (TA14), VI.2.1.1.2.2 (SD19), VI.1.2.2.2 (SD16), and VII (JN08) could replicate efficiently in chicken embryo fibroblasts, while the replication titer of JN08 (VII) virus was significantly lower than that of VI gene viruses in pigeon embryo fibroblasts. The TA14 (VI.2.1.1.2.1) and SD19 (VI.2.1.1.2.2) viruses caused 20 % and 30 % mortality in pigeons, respectively. No birds infected with SD16 (VI.1.2.2.2) died during the study period. JN08 (VII) virus did not cause obvious clinical signs in infected pigeons. All data indicated that VI.2.1.1.2.2 is the prevalent genotype circulating in China and poses a major threat to pigeons, suggesting that a matched vaccine is necessary to control the disease.
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http://dx.doi.org/10.1016/j.vetmic.2020.108661DOI Listing
May 2020

Membrane Retraction Technique in Bypass Surgery for the Treatment of Adult Moyamoya Disease with Deep-Seated Recipient Artery.

World Neurosurg 2020 07 21;139:294-297. Epub 2020 Apr 21.

Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, People's Republic of China. Electronic address:

Objective: To introduce a membrane retraction technique that can provide good exposure of deep-seated recipient arteries in cortical sulci and simplify the anastomosis procedure.

Methods: Only those adult patients with moyamoya disease who underwent superficial temporal artery to middle cerebral artery bypass surgery during which the suitable recipient arteries were located deep in cortical sulci were included in this retrospective study. By placing 10-0 prolene sutures to the arachnoid membrane of the 2 banks of sulcus, arachnoid retraction was applied to pull the sulcus apart and then the deep-seated recipient arteries were exposed. Standard end-to-side anastomosis was completed. The mean occlusion time and successful rate were recorded and compared with those of the normal procedure.

Results: From June to November 2019, 124 superficial temporal artery to middle cerebral artery bypass surgeries for the treatment of moyamoya disease were performed in Nanfang Hospital. The membrane retraction technique was used in 5 patients (5/110, 4.5%) and the success rates were 100%. The mean temporary occlusion time was 27.2 minutes. No procedure-related complications were observed. All patients recovered uneventfully. The postoperative angiograms confirmed good patency of bypass grafts in all 5 cases.

Conclusions: The membrane retraction technique is an effective and safe method for the treatment of adult patients with moyamoya disease with deep-seated recipient arteries within the sulci.
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http://dx.doi.org/10.1016/j.wneu.2020.04.090DOI Listing
July 2020

Isolation and pathogenicity testing of avian reticuloendotheliosis virus from layer chickens in China.

J Vet Diagn Invest 2020 May 1;32(3):389-393. Epub 2020 Apr 1.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine (A. Xu, Huo, Zhong, Tian, Zhang, Hu).

Reticuloendotheliosis virus (REV) can cause runting, immunosuppression, acute reticulum cell neoplasia, and chronic lymphoid tumors in a variety of domestic and wild birds. We diagnosed a case of reticuloendotheliosis with obvious tumors in liver and kidney. We isolated and sequenced the virus and performed pathogenicity testing of the REV strain. Immunohistochemistry and PCR confirmed that the diseased layer chickens were infected with REV. The strain, named BJ1503, was successfully isolated from the case by inoculation of tissue homogenates onto chicken embryo fibroblasts. The length of the proviral REV genome is 8,293 nucleotides. The isolate had 99.7% identity with REV-HA9901 (AY842951.1), which was isolated from Jiangsu, China, in 1999. The chickens infected with REV-BJ1503 had depressed weight gain and lymphoid atrophy. Our findings suggest that REV isolate BJ1503 was phylogenetically close to the earlier strain found in China, with minor variations, and the virus was associated with severe production problems.
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http://dx.doi.org/10.1177/1040638720914881DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7377614PMC
May 2020

A novel EDA1 missense mutation in X-linked hypohidrotic ectodermal dysplasia.

Medicine (Baltimore) 2020 Mar;99(11):e19244

Department of Prosthodontics, School and Hospital of Stomatology, Hebei Medical University and Hebei Key Laboratory of Stomatology, Shijiazhuang.

A mutation in the epithelial morphogen gene ectodysplasin-A1 (EDA1) is responsible for the disorder X-linked hypohidrotic ectodermal dysplasia (XLHED), the most common form of ectodermal dysplasia. XLHED is characterized by impaired development of hair, eccrine sweat glands, and teeth. This study aimed to identify potentially pathogenic mutations in four Chinese XLHED families.Genomic DNA was extracted from the peripheral blood and sequenced. Sanger sequencing was used to carry out mutational analysis of the EDA1 gene, and the three-dimensional structure of the novel mutant residues in the EDA trimer was determined. Transcriptional activity of NF-κB was tested by Dual luciferin assay.We identified a novel EDA1 mutation (c.1046C>T) and detected 3 other previously-reported mutations (c.146T>A; c.457C>T; c.467G>A). Our findings demonstrated that novel mutation c.1046C>T (p.A349 V) resulted in XLHED. The novel mutation could cause volume repulsion in the protein due to enlargement of the amino acid side chain. Dual luciferase assay revealed that transcriptional NF-κB activation induced by XLHED EDA1 protein was significantly reduced compared with wild-type EDA1.These results extend the spectrum of EDA1 mutations in XLHED patients and suggest a functional role of the novel mutation in XLHED.
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http://dx.doi.org/10.1097/MD.0000000000019244DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7220389PMC
March 2020

Pathogenicity and genome changes in QX-like infectious bronchitis virus during continuous passaging in embryonated chicken eggs.

Virus Res 2020 05 3;281:197911. Epub 2020 Mar 3.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, People's Republic of China. Electronic address:

Infectious bronchitis (IB) remains a major problem in the global poultry industry despite the many available vaccines. Live attenuated vaccines are the most effective means of preventing IB and are traditionally generated by serial passaging of a wild strain in embryonated chicken eggs. In this study, the SZ isolate of the QX-like infectious bronchitis virus (IBV) was continuously passaged in chicken embryos for 250 passages. We compared the pathogenicity of different passages (SZ50, SZ100, SZ150, SZ200 and SZ250) of strain SZ by clinical signs, gross lesions, viral load, tissue tropism, weight gain and tracheal ciliary activity. As the passaging increased in the chicken embryos, the strain lost its ability to infect many organs, and the viral pathogenicity gradually decreased. We also found 23 genomic variations of the QX-like strain SZ throughout the passaging process by further analyzing its complete genome sequence. This work offers valuable insight for IBV vaccine development and further research on the IBV attenuation mechanisms.
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http://dx.doi.org/10.1016/j.virusres.2020.197911DOI Listing
May 2020

Complete genome sequence and phylogenetic analysis of novel avastroviruses circulating in China from 2016 to 2018.

Virus Res 2020 03 3;278:197858. Epub 2020 Jan 3.

Key Laboratory of Animal Epidemiology of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, 100193, Beijing, China; Diagnostic & Research Center of Livestock and Poultry Epidemic Diseases, China Agricultural University, 100193, Beijing, China. Electronic address:

Avastrovirus-specific antibodies are widely detected in chickens in China. However, there are currently no commercially available vaccines for this group of viruses. To address this issue, we collected 76 tissue samples from Avastrovirus (AAstVs) antibody-positive chickens from farms across eight provinces in China from 2016 to 2018. The samples were then screened for the presence of AAstVs sequences by polymerase chain reaction analysis and a phylogenetic tree was constructed. Specific primers were designed to amplify the whole genome sequences of the viruses from four positive samples, with the genetic characteristics and structures of the resulting genomes then analyzed further. Overall, 42 (55.3 %) of the 76 samples were positive for AAstVs RNA. Phylogenetic analysis along with the ORF1b gene showed that 15 isolates were grouped in AAstV-1 and 27 of them were grouped in AAstV-2. None of the isolates was belonged to AAstV-3. Sequencing and structural analyses revealed that the genomes of the four isolates showed the typical characteristics of AAstVs genomes but were genetically distinct from other AAstVs. The results of this study will contribute to our understanding of the genetic characteristics of AAstVs in China.
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http://dx.doi.org/10.1016/j.virusres.2020.197858DOI Listing
March 2020

Phylogenetic analyses and pathogenicity of a variant infectious bursal disease virus strain isolated in China.

Virus Res 2020 01 3;276:197833. Epub 2019 Dec 3.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China. Electronic address:

Infectious bursal disease is an acute, highly contagious, immunosuppressive disease of young chickens caused by infectious bursal disease virus (IBDV). In recent years, there has been a notable increase in the isolation rates of variant IBDV strains in China; however, the pathogenicity of these variants is unclear. In the current study, we characterized variant IBDV strain ZD-2018-1 and assessed its pathogenicity in specific-pathogen-free chickens. Phylogenetic analysis revealed that ZD-2018-1 belonged to the variant IBDV strain, which showed several unique amino acid mutations compared with other previously-isolated variant IBDV strains. Pathogenicity assays showed that ZD-2018-1 was less virulent than very virulent IBDV strain SD-2013-1, and did not cause an obvious symptoms or death. In comparison, strain SD-2013-1 had a high mortality rate and caused severe lesions in various tissues. However, both of the strains induced obvious pathological lesions on the bursa of Fabricius, resulting in severe immunosuppression in the infected chickens. The results of this study present a systematic evaluation of the genetic characteristics, pathogenicity, and immunosuppressive properties of a new variant IBDV strain, and may help in the development of strategies for the prevention and control of IBDV in poultry.
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http://dx.doi.org/10.1016/j.virusres.2019.197833DOI Listing
January 2020

Characterization of emergent Avibacterium paragallinarum strains and the protection conferred by infectious coryza vaccines against them in China.

Poult Sci 2019 Dec;98(12):6463-6471

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.

Infectious coryza (IC), an acute respiratory disease of chickens, is caused by Avibacterium paragallinarum. Here, the current epidemiological status of IC was investigated in China over 5 yr (2013 to 2018). A total of 28 Av. paragallinarum field isolates were identified by PCR tests and by sequence analysis of the hemagglutinin gene. The pathogenicities of 4 field isolates, the efficacy of 2 commercial inactivated oil-emulsion IC vaccines and vaccines containing different Av. paragallinarum isolates were also evaluated. The PCRs revealed a high rate (51.5%) of sample positivity for Av. paragallinarum during 2013 to 2018. Phylogenetic analysis showed that most field strains fell into the same cluster and had a farther genetic relationship with the early isolates from China. Pathogenicity testing revealed that the Chinese Av. paragallinarum isolates were able to induce the typical clinical signs of IC; hence, they were clearly pathogenic to chickens. Vaccine efficacy tests revealed that the 2 commercial inactivated oil-emulsion IC vaccines we tested had low protection rates against 2 selected Av. paragallinarum isolates after a single immunization, whereas the inactivated vaccine containing the Av. paragallinarum BJ26 isolate generated a relatively high protection rate against the field isolates compared with other three tested vaccines. The results indicate that IC is currently prevalent in China, and that commercial vaccines have not counteracted its presence in this country.
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http://dx.doi.org/10.3382/ps/pez531DOI Listing
December 2019

Endoplasmic Reticulum Stress-Mediated Basolateral Amygdala GABAergic Neuron Injury Is Associated With Stress-Induced Mental Disorders in Rats.

Front Cell Neurosci 2019 14;13:511. Epub 2019 Nov 14.

Hebei Key Laboratory of Forensic Medicine, Department of Forensic Medicine, Collaborative Innovation Center of Forensic Medical Molecular Identification, Hebei Medical University, Shijiazhuang, China.

The amygdala is an important center of fear learning and memory and plays a critical role in regulating stress disorders. Previous studies have shown that changes in the amygdala caused by stress are an important cause of mental disorders including anxiety, but the specific mechanism remains unclear. Therefore, the purpose of this study was to investigate whether mental disorders induced by stress are related to γ-aminobutyric acid (GABA)ergic neuron damage in the basolateral amygdala (BLA) and whether endoplasmic reticulum stress (ERS) is involved in the injury process. Rat models of different durations of stress were established by restraint and forced ice-water swimming. Behavioral tests and high-performance liquid chromatography (HPLC) were used to detect anxiety in rats and changes in neurotransmitter levels in the BLA. Morphological approaches and microscopy-based multicolor tissue cytometry (MMTC) were used to detect the damage-induced changes in GABAergic neurons in the BLA. Immunofluorescence double labeling was used to detect the expression of ERS-related proteins before and after the inhibition of protein kinase R-like endoplasmic reticulum kinase (PERK) pathway. Stress resulted in damage to GABAergic neurons in the BLA, decreased GABA and increased glutamic acid (GLU) levels, perturbation of the excitation/inhibition (E/I) ratio in the BLA, and obvious anxiety disorders in rats. Moreover, ERS-mediated GABAergic neuron injury was an important cause of neurotransmitter level changes in the BLA. These results suggested that ERS-mediated GABAergic neuron injury in the BLA may be an important cause of stress-induced mental disorders.
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http://dx.doi.org/10.3389/fncel.2019.00511DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6874131PMC
November 2019

The S2 Subunit of QX-type Infectious Bronchitis Coronavirus Spike Protein Is an Essential Determinant of Neurotropism.

Viruses 2019 10 22;11(10). Epub 2019 Oct 22.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.

Some coronaviruses (CoVs) have an extra furin cleavage site (RRKR/S, furin-S2' site) upstream of the fusion peptide in the spike protein, which plays roles in virion adsorption and fusion. Mutation of the S2' site of QX genotype (QX-type) infectious bronchitis virus (IBV) spike protein (S) in a recombinant virus background results in higher pathogenicity, pronounced neural symptoms and neurotropism when compared with conditions in wild-type IBV (WT-IBV) infected chickens. In this study, we present evidence suggesting that recombinant IBV with a mutant S2' site (furin-S2' site) leads to higher mortality. Infection with mutant IBV induces severe encephalitis and breaks the blood-brain barrier. The results of a neutralization test and immunoprotection experiment show that an original serum and vaccine can still provide effective protection in vivo and in vitro. This is the first demonstration of IBV-induced neural symptoms in chickens with encephalitis and the furin-S2' site as a determinant of neurotropism.
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http://dx.doi.org/10.3390/v11100972DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6832359PMC
October 2019

Appropriate amount of W protein of avian avulavirus 1 benefits viral replication and W shows strain-dependent subcellular localization.

Virology 2019 12 27;538:71-85. Epub 2019 Sep 27.

Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China. Electronic address:

In order to confirm the existence of W protein in Avian avulavirus 1 (AAvV-1) infected cells, two monoclonal antibodies were prepared. The presence of W protein in cells infected with lentogenic genotype II strain La Sota or velogenic genotype VII strain SG10 was confirmed with immunofluorescence and western blotting assays. W localized to the cytoplasm, whereas W localized to the nucleus. The influence of W protein was investigated in vitro and in vivo with two AAvV-1 strains defective in the W C-terminus. The growth kinetic curves and pathogenicity tests in 3-week-old SPF chickens both showed that the replication abilities of strains with C-terminally deleted W proteins were lower than that of the parental strain. Restoring the appropriate dose of W protein increased the viral titers of these strains. The expression validation and functional exploration of W protein will facilitate our understanding of pathogenic mechanism of AAvV-1.
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http://dx.doi.org/10.1016/j.virol.2019.09.013DOI Listing
December 2019