Stem-Loop I of the Tembusu Virus 3'-Untranslated Region Is Responsible for Viral Host-Specific Adaptation and the Pathogenicity of the Virus in Mice

Tembusu virus (TMUV), an avian mosquito-borne flavivirus, was first identified from Culex tritaeniorhynchus in 1955. To validate the effects of the 3'-untranslated region (3'UTR) in viral host-specific adaptation, we generated a set of chimeric viruses using CQW1 (duck strain) and MM 1775 (mosquito strain) as backbones with heterogeneous 3'UTRs. Compared with rMM 1775, rMM-CQ3'UTR (recombinant MM 1775 virus carrying the 3'UTR of CQW1) exhibited enhanced proliferation in vitro, with peak titers increasing by 5-fold in duck embryonic fibroblast (DEF) cells or 12-fold in baby hamster kidney (BHK-21) cells; however, the neurovirulence of rMM-CQ3'UTR was attenuated in 14-day-old Kunming mice via intracranial injection, with slower weight loss, lower mortality, and reduced viral loads. In contrast, rCQ-MM3'UTR showed similar growth kinetics in vitro and neurovirulence in mice compared with those of rCQW1. Then, the Stem-loop I (SLI) structure, which showed the highest variation within the 3'UTR between CQW1 and MM 1775, was further chosen for making chimeric viruses. The peak titers of rMM-CQ3'UTRSLI displayed a 15- or 4-fold increase in vitro, and the neurovirulence in mice was attenuated, compared with that of rMM 1775; rCQ-MM3'UTRSLI displayed comparable multiplication ability in vitro but was significantly attenuated in mice, in contrast with rCQW1. In conclusion, we demonstrated that the TMUV SLI structure of the 3'UTR was responsible for viral host-specific adaptation of the mosquito-derived strain in DEF and BHK-21 cells and regulated viral pathogenicity in 14-day-old mice, providing a new understanding of the functions of TMUV 3'UTR in viral host switching and the pathogenicity changes in mice. IMPORTANCE Mosquito-borne flaviviruses (MBFVs) constitute a large number of mosquito-transmitted viruses. The 3'-untranslated region (3'UTR) of MBFV has been suggested to be relevant to viral host-specific adaptation. However, the evolutionary strategies for host-specific fitness among MBFV are different, and the virulence-related structures within the 3'UTR are largely unknown. Here, using Tembusu virus (TMUV), an avian MBFV as models, we observed that the duck-derived SLI of the 3'UTR significantly enhanced the proliferation ability of mosquito-derived TMUV in baby hamster kidney (BHK-21) and duck embryonic fibroblast (DEF) cells, suggesting that the SLI structure was crucial for viral host-specific adaptation of mosquito-derived TMUVs in mammalian and avian cells. In addition, all SLI mutant viruses exhibited reduced viral pathogenicity in mice, indicating that SLI structure was a key factor for the pathogenicity in mice. This study provides a new insight into the functions of the MBFV 3'UTR in viral host switching and pathogenicity changes in mice.

Depletion of SASH1, an astrocyte differentiation-related gene, contributes to functional recovery in spinal cord injury

AIMS

This study aimed to evaluate the effects of the depletion of SAM and SH3 domain-containing protein 1 (SASH1) on functional recovery after spinal cord injury (SCI) and to investigate the possible mechanism of SASH1 knockdown in astrocytes facilitating axonal growth.

METHODS

SCI model was established in adult rats. SASH1 small interfering RNA (siSASH1) was used to investigate its function. Hindlimb motor function was evaluated by the Basso-Bresnahan-Beattie (BBB) assay. The gene expressions were evaluated by the methods of qRT-PCR, Western-blotting, ELISA, and immunohistochemistry.

RESULTS

SASH1 knockdown improved the BBB scores after SCI and significantly reduced GFAP expression. In cultured spinal astrocytes, siSASH1 treatment decreased interferon-γ release and increased brain-derived neurotrophic factor (BDNF) release. When cocultured with SASH1-knockdown astrocytes, axonal growth increased. The neuronal tropomyosin receptor kinase B (BDNF receptor) expression increased, especially in the axonal tips. SASH1 expression increased while NSCs differentiated into glial cells, instead of neurons. After SASH1 depletion, differentiated NSCs maintained a higher level of Nestin protein and an increase in BDNF release.

CONCLUSIONS

These results indicate that SASH1 acts as an astrocytic differentiation-maintaining protein, and SASH1 downregulation limits glial activation and contributes toward functional recovery after SCI.

Duck plague virus US3 protein kinase phosphorylates UL47 and regulates the subcellular localization of UL47

Duck plague virus (DPV) belongs to the alphaherpesvirinae and causes high morbidity and mortality in waterfowl. UL47 is a large abundant structural protein in DPV, which means that UL47 protein plays an important role in virus replication. US3 protein, as a viral protein kinase in alphaherpesviruses, has been reported to be critical for DPV virion assembly. In this study, we over-expressed UL47 and US3 proteins and found that DPV UL47 protein was a phosphorylated substrate of US3 protein, which interacted and co-localized with US3 protein in the cytoplasm. US3-regulated phosphorylation of UL47 was important for the cytoplasmic localization of UL47 because non-phosphorylated UL47 was localized in the nucleus. The six sites of UL47 at Thr29, Ser30, Ser42, Thr47, Ser161, and Thr775 were identified as the phosphorylation targets of US3 protein. In vivo, UL47 phosphorylation was also detected but not in ΔUS3-infected cells. US3 protein promoted the cytoplasmic localization of UL47 at the late stage of infection, and the lack of US3 protein caused a delay in UL47 translocation to the cytoplasm. These results enhance our understanding of the functions of US3 during DPV infection and provide some references for DPV assembly.

Phenotypic and genotypic characterization of antimicrobial resistance profiles in Salmonella isolated from waterfowl in 2002–2005 and 2018–2020 in Sichuan, China

Salmonella enterica is a widespread foodborne pathogen with concerning antimicrobial resistance (AMR). Waterfowl are a major source of Salmonella transmission, but there are few systematic studies on Salmonella prevalence in waterfowl species. In this study, 126 Salmonella isolates (65 collected in 2018–2020 and 61 collected in 2002–2005) were obtained from waterfowl samples in Sichuan, China. Their serotypes, pulsed-field gel electrophoresis (PFGE) types, and phenotypic and genotypic AMR profiles were systematically examined. The isolates were distributed in 7 serotypes, including serovars Enteritidis (46.0%), Potsdam (27.8%), Montevideo (7.9%), Cerro (6.3%), Typhimurium (4.8%), Kottbus (4.0%) and Apeyeme (3.2%). Their PFGE characteristics were diverse; all isolates were distributed in four groups (cutoff value: 60.0%) and 20 clusters (cutoff value: 80.0%). Moreover, all isolates were multidrug resistant, and high rates of AMR to lincomycin (100.0%), rifampicin (100.0%), sulfadiazine (93.7%), erythromycin (89.7%), ciprofloxacin (81.0%), and gentamicin (75.4%) were observed. Finally, 49 isolates were subjected to whole-genome sequencing, and a wide variety of AMR genes were found, including multiple efflux pump genes and specific resistance genes. Interestingly, the tet(A)/tet(B) and catII resistance genes were detected in only isolates obtained in the first collection period, while the gyrA (S83F, D87N and D87G) and gyrB (E466D) mutations were detected at higher frequencies in the isolates obtained in the second collection period, supporting the findings that isolates from different periods exhibited different patterns of resistance to tetracycline, chloramphenicol and nalidixic acid. In addition, various incompatible plasmid replicon fragments were detected, including Col440I, Col440II, IncFIB, IncFII, IncX1, IncX9, IncI1-I and IncI2, which may contribute to the horizontal transmission of AMR genes and provide competitive advantages. In summary, we demonstrated that the Salmonella isolates prevalent in Sichuan waterfowl farms exhibited diverse serotypes, multiple AMR phenotypes and genotypes, and AMR changes over time, indicating their potential risks to public health.

Associations of comorbidity patterns and in-hospital outcomes in Chinese young females (<55 years) presenting with ST-segment elevation myocardial infarction: a nationwide registry study

Background

Recent evidence demonstrated an increasing trend for acute myocardial infarction (MI) incidence in young females globally. Identification of distinct clinical comorbidity patterns in this population may allow more precise therapy and improvement in clinical care.

Purpose

This study was designed to identify specific comorbidity patterns and to examine their associations with in-hospital outcomes in female ST-Segment Elevation Myocardial Infarction (STEMI) patients under 55 years of age based on the China Chest Pain Center (CCPC) Database.

Methods

From March 7, 2017, to December 29, a total of 267,405 STEMI patients (66,568 females, 24.9%) were admitted to CCPC. Comorbidity patterns were derived among 6,024 female patients (48.5±5.6 years old) under 55 years of age, using hierarchical clustering applied to 15 medical conditions/histories. The study outcome was defined as the composite of in-hospital adverse events (death, new-onset/worsening heart failure, mechanical complications, recurrent MI, and cerebral ischemic stroke). Associations between multimorbidity patterns and clinical outcomes were evaluated by multivariable-adjusted logistic regression models.

Results

Three comorbidity patterns were derived based on hierarchical clustering, including P1 (histories of hypertension, cerebrovascular disease, heart failure and coronary artery disease), P2 (histories peripheral arterial disease, atrial fibrillation, thyroid dysfunction, anemia, chronic kidney disease, cerebrovascular disease and peptic ulcer) and P3 (obesity, histories of hyperlipidemia, diabetes and smoking, family history of cardiovascular diseases). After adjustment for age, admission levels of systolic blood pressure and heart rate, receiving reperfusion treatment or not, and medical therapies in-hospital (antiplatelet drugs, statins, β-blockers and anticoagulants), compared with participants without multimorbidity, P1 (odds ratios [OR] = 1.60, 95% confidence interval [CI]: 1.26 to 2.04) and P3 (OR = 1.45, 95% CI: 1.10 to1.92) demonstrated relatively higher risks for in-hospital composite outcomes. Compared with patients without comorbidity patterns, the clustering of the above comorbidity patterns dose-dependently augmented the risks for in-hospital composite outcomes, from any one pattern (OR = 1.49, 95% CI: 1.23 to1.81), to any two patterns (OR = 2.46, 95% CI: 1.82 to 3.34) and to three patterns (OR = 4.51, 95% CI: 1.12 to 18.16).

Conclusion

In a nationwide STEMI registry, our results provided the proof-of-concept evidence that specific comorbidity patterns of young female STEMI were associated with differential in-hospital outcomes. Further work is needed to validate the utility and values in decision making of these multimorbidity patterns for appropriate management strategies in young female STEMI patients.

Funding Acknowledgement

Type of funding sources: None.

[Clinical efficacy of split liver transplantation in the treatment of children with biliary atresia]

Objective: To compare the clinical efficacy of split liver transplantation (SLT) and living donor liver transplantation(LDLT) in the treatment of children with biliary atresia. Methods: The clinical data of 64 children with biliary atresia who underwent SLT and 44 children who underwent LDLT from June 2017 to May 2022 at Liver Surgery & Liver Transplantation Center,the Third Affiliated Hospital of Sun Yat-sen University were retrospectively analyzed. Among the children who received SLT, there were 40 males and 24 females. The median age at transplantation was 8 months (range:4 to 168 months). Among the patients who received LDLT, there were 24 males and 20 females. The age at transplantation ranged from 4 to 24 months,with a median age of 7 months. Sixty-four children with biliary atresia were divided into two groups according to the SLT operation time: 32 cases in the early SLT group(June 2017 to January 2019) and 32 cases in the technically mature SLT group (February 2019 to May 2022). Rank sum test or t test was used to compare the recovery of liver function between the LDLT group and the SLT group,and between the early SLT group and the technically mature SLT group. The incidence of postoperative complications was compared by χ² test or Fisher exact probability method. Kaplan-Meier method and Log-rank test were used for survival analysis. Results: The cold ischemia time(M (IQR)) (218 (65) minutes), intraoperative blood loss(175 (100) ml) and graft-to-recipient body weight ratio (3.0±0.7) in the LDLT group were lower than those in the SLT group(500 (130) minutes, 200 (250) ml, 3.4±0.8) (Z=-8.064,Z=-2.969, t=-2.048, all P<0.05). The cold ischemia time(457(158)minutes) and total hospital stay ((37.4±22.4)days) in the technically mature SLT group were lower than those in the early SLT group(510(60)minutes, (53.0±39.0)days).The differences were statistically significant (Z=-2.132, t=1.934, both P<0.05).The liver function indexes of LDLT group and SLT group showed unimodal changes within 1 week after operation. The peak values of ALT, AST, prothrombin time, activeated partial thromboplasting time, international normalized ratio, fibrinogen and creatinine all appeared at 1 day after operation, and the peak value of prothrombin activity appeared at 3 days after operation. All indicators returned to normal at 7 days after operation. The 1-,2-,and 3-year overall survival rates were 95.5% in LDLT group and 93.5% in the technically mature SLT group, and the difference was not statistically significant. The 1-,2-,and 3-year overall survival rates were 90.2% in the early SLT group and 93.5% in the technically mature SLT group, and there was no significant difference between the two groups(P>0.05). The main complications of the early SLT group were surgery-related complications(28.1%,9/32), and the main complications of the technically mature SLT group were non-surgery-related complications(21.9%,7/32). There were 5 deaths in the SLT group,including 4 in the early SLT group and 1 in the technically mature SLT group. Conclusion: The survival rate of SLT in the treatment of biliary atresia is comparable to that of LDLT.

Dissemination and prevalence of plasmid-mediated high-level tigecycline resistance gene tet (X4)

With the large-scale use of antibiotics, antibiotic resistant bacteria (ARB) continue to rise, and antibiotic resistance genes (ARGs) are regarded as emerging environmental pollutants. The new tetracycline-class antibiotic, tigecycline is the last resort for treating multidrug-resistant (MDR) bacteria. Plasmid-mediated horizontal transfer enables the sharing of genetic information among different bacteria. The tigecycline resistance gene tet(X) threatens the efficacy of tigecycline, and the adjacent ISCR2 or IS26 are often detected upstream and downstream of the tet(X) gene, which may play a crucial driving role in the transmission of the tet(X) gene. Since the first discovery of the plasmid-mediated high-level tigecycline resistance gene tet(X4) in China in 2019, the tet(X) genes, especially tet(X4), have been reported within various reservoirs worldwide, such as ducks, geese, migratory birds, chickens, pigs, cattle, aquatic animals, agricultural field, meat, and humans. Further, our current researches also mentioned viruses as novel environmental reservoirs of antibiotic resistance, which will probably become a focus of studying the transmission of ARGs. Overall, this article mainly aims to discuss the current status of plasmid-mediated transmission of different tet(X) genes, in particular tet(X4), as environmental pollutants, which will risk to public health for the “One Health” concept.

Factors associated with depression in residents in the post-epidemic era

OBJECTIVE

To explore the factors associated with depression in residents in the post-epidemic era of COVID-19.

METHODS

A multi-stage stratified random sampling method was used to conduct a questionnaire survey among community residents through self-designed questionnaires and self-rating depression scale (SDS). Multivariate logistic regression analysis was performed on the influencing factors of depressive symptoms.

RESULTS

A total of 1993 residues completed the survey of depression status. The incidence of depressive symptoms was 27.04%. The multivariate logistic regression analysis showed that female (odds ratio (OR): 6.239, 95% confidence interval (CI): 2.743-10.698), body mass index (BMI) > 24 (OR: 2.684, 95% CI: 1.059-3.759) and drinking (OR: 1.730, 95% CI: 1.480-3.153) were the risk factors for developing depressive symptoms. Married (OR: 0.417, 95% CI: 0.240-0.652), monthly income (3001-5000 yuan, OR: 0.624, 95% CI: 0.280-0.756; >5000 yuan, OR: 0.348, 95% CI: 0.117-0.625), ordinary residents (OR: 0.722, 95% CI: 0.248-0.924) and urban residents (OR: 0.655, 95% CI: 0.394-0.829) were the protective factors of depressive symptoms.

CONCLUSIONS

Under the post-epidemic era of COVID-19, depressive symptoms are still common among community residents in China. Gender, BMI, drinking, marriage, monthly income and nature of personnel and residential area are associated with the incidence of depressive symptoms.

[Association of nutritional status with clinical outcomes of stroke patients with acute anterior circulation large vessel occlusion after emergency endovascular treatment]

OBJECTIVE

To explore the influence of nutritional status on 90-day functional outcomes of stroke patients with acute large vessel occlusion in the anterior circulation after endovascular treatment (EVT).

METHODS

We retrospectively analyzed the baseline, laboratory, surgical and 90-day follow-up data of patients with stroke resulting from acute large vessel occlusion in the anterior circulation, who underwent emergency endovascular treatment in our hospital from July, 2015 to December, 2020. A favorable outcome was defined as a modified Rankin scale score ≤2 at 90 days. Univariate and multivariate regression analyses were performed to explore the relationship between nutritional status and 90-day functional outcomes of the patients.

RESULTS

A total of 459 patients (mean age of 68.29±11.21 years, including 260 males) were enrolled in this study. According to their prognostic nutritional index (PNI), the patients were divided into normal nutrition group (392 cases, 85.4%), moderate malnutrition group (44 cases, 9.6%), and severe malnutrition group (23 cases, 5.0%). Univariate analysis showed that the patients with good clinical outcomes had a lower proportion of malnutrition with a younger age, a lower rate of diabetes, lower baseline blood pressure, lower baseline NIHSS score, higher baseline ASPECT score, and higher rates of good collateral circulation and complete vascular recanalization. Multivariate analysis showed that in addition to age, diabetes, baseline systolic blood pressure, successful recanalization, baseline ASPECT score, baseline NIHSS score and collateral circulation, a greater PNI was a protective factor for a good 90-day outcome of patients after EVT (moderate vs severe: OR=0.245, 95% CI: 0.066-0.908, P=0.035; normal vs severe: OR=0.185, 95% CI: 0.059-0.581, P=0.004).

CONCLUSION

Nutritional status an important factor affecting the 90-day outcomes after EVT of stroke patients with acute large vessel occlusion in the anterior circulation.

Molecular cloning, functional characterization of duck TRADD and its effect on infection with duck Tembusu virus

Tumor necrosis factor receptor 1 (TNFR1) associated death domain protein (TRADD) is a pivotal adaptor in TNF signaling pathway and plays an important role in apoptosis and immune regulation. The function of TRADD has been investigated extensively in mammals, however, the role of TRADD in ducks remains obscure. To reveal the function of duck TRADD (duTRADD) in the apoptosis and innate immune response, the TRADD homologue of mallard (Anas platyrhynchos) has been cloned and the function of duTRADD is investigated in this study. We conducted sequence analysis of the duTRADD, the open reading frame (ORF) region of duTRADD gene was 1065 bp, encoding 354 amino acids (aa), which shares similar functional domain to its mammalian counterpart. Tissue distribution profile of duTRADD in 7-day-old ducklings showed that the expression level of the gene was the highest in heart, followed by liver and brain. Accordingly, duck Tembusu virus (DTMUV) has been shown to decrease duTRADD expression, while overexpression of duTRADD inhibited DTMUV replication in a dose-dependent manner. Furthermore, duTRADD activated the transcriptional activity of caspase-3/8/9, the flow cytometry showed that duTRADD significantly induced apoptosis. However, duTRADD showed hardly any effect on the transcriptional activity of IFN-α/β and its downstream interferon-stimulated genes (ISGs). The current data support the conclusion that duTRADD is a novel pro-apoptotic protein with a critical role in defense against DTMUV invasion. These results lay the theoretical foundation for the development of new anti-DTMUV strategies.

Optimising diffusion-weighted imaging of the thyroid gland using dedicated surface coil

AIM

To assess the feasibility of applying field-of-view (FOV) optimised and constrained undistorted single-shot (FOCUS) diffusion-weighted imaging (DWI) in the thyroid gland by comparing its image quality with conventional DWI (C-DWI) qualitatively and quantitatively using a dedicated surface coil exclusively designed for the thyroid gland at 3 T magnetic resonance imaging (MRI).

MATERIALS AND METHODS

In this prospective study, 32 healthy volunteers who had undergone 3 T the thyroid gland MRI with FOCUS-DWI and C-DWI were enrolled. Two independent reviewers assessed the overall image quality, artefacts, sharpness, and geometric distortion based on a five-point Likert scale. The signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC) were quantified for both sequences. Interobserver agreement, qualitative scores, and quantitative parameters were compared between two sequences.

RESULTS

Agreement between the two readers was good for FOCUS-DWI (κ = 0.714-0.778) and moderate to good for C-DWI (κ = 0.525-0.672) in qualitative image quality assessment. Qualitatively, image quality (overall image quality, artefacts, sharpness, and geometric distortion) was significantly better in FOCUS-DWI than that in the C-DWI (all p<0.05); however, quantitatively, FOCUS-DWI had significantly lower SNRs (p<0.001) and CNRs (p=0.012) compared with C-DWI. The ADC value on FOCUS-DWI was significantly higher than that on C-DWI (p<0.001).

CONCLUSION

FOCUS-DWI depicted the thyroid gland with significantly better image quality qualitatively and less ghost artefacts, but had significantly lower SNR and CNR quantitatively, compared with C-DWI, suggesting that both DWI sequences have advantages and could be chosen for different purposes.

Multiple functions of heterogeneous nuclear ribonucleoproteins in the positive single-stranded RNA virus life cycle

The heterogeneous nuclear ribonucleoproteins (hnRNPs) are a diverse family of RNA binding proteins that are implicated in RNA metabolism, such as alternative splicing, mRNA stabilization and translational regulation. According to their different cellular localization, hnRNPs display multiple functions. Most hnRNPs were predominantly located in the nucleus, but some of them could redistribute to the cytoplasm during virus infection. HnRNPs consist of different domains and motifs that enable these proteins to recognize predetermined nucleotide sequences. In the virus-host interactions, hnRNPs specifically bind to viral RNA or proteins. And some of the viral protein-hnRNP interactions require the viral RNA or other host factors as the intermediate. Through various mechanisms, hnRNPs could regulate viral translation, viral genome replication, the switch of translation to replication and virion release. This review highlights the common features and the distinguish roles of hnRNPs in the life cycle of positive single-stranded RNA viruses.

Emergence of a floR-carrying Plasmid in Extended Spectrum β-lactamase (ESBL) Producing Pasteurella aerogenes, Isolated from an Avian Species in China

Identification and analysis of the antimicrobial resistance of Pasteurella aerogenes (P. aerogenes) isolated from poultry. For susceptibility testing in accordance with the CLSI, plasmids were extracted via alkaline lysis and transferred by CaCl₂ treatment. Genomic DNA of a representative P. aerogenes isolate was subjected to whole genome sequencing. CCCP was utilized to determine whether SF190908 contains an efflux pump. The bla_VEB gene was ligated with the pET-28 plasmid and transferred to Escherichia coli to verify it as an ESBL gene. SF190908 isolated from poultry was identified as P. aerogenes based upon biochemical and 16s rRNA results. The isolate showed high MIC values for eight antimicrobials. Sequencing results showed that the mobile element-mediated antimicrobial resistance gene cluster conferred antimicrobial resistance on the strain, and a single 5,105-bp plasmid, designated pRCAD0752PA-1, was isolated. Four antimicrobial resistance gene clusters were identified in the SF190908 chromosome; one antimicrobial resistance gene cluster carried the bla_VEB gene, which was verified as ESBL according to the CLSI and was detected in Pasteurellaceae for the first time, to the best of our knowledge. The efflux pump may confer antimicrobial resistance to SF190908. P. aerogenes isolated from poultry showed resistance genes encoded in mobile elements that confer multi-antimicrobial resistance to SF190908. The antimicrobial-resistant plasmid pRCAD0752PA-1 was isolated in SF190908 and conferred resistance to florfenicol. This study indicates an urgent need to increase efforts to monitor the spread of P. aerogenes multi-antimicrobial-resistant strains and plasmids, especially in newly discovered at-risk species such as poultry.

Analysis of the mechanism regulating the killing effect of EBNA1 on EBV-associated B-cell tumors

In order to analysis of the mechanisms regulating EBNA1 killing of EBV associated B cell tumors, preparations were first made for EBV-associated B cells, and the cells were subsequently transformed. The killing effect of ebna1-28 T cells on EBV-positive B cell lymphoid tumor cells was detected using the FACS method. SF rats were also selected to analyze the inhibitory effect of ebna1-28t on transplanted tumors in nude mice with EBV-positive B cell lymphoma. Results showed that compared with the untransfected group, the expression of EBNA1 was higher in the empty plasmid SFG group, the recombinant plasmid rv-ebna1/car group compared with the empty plasmid SFG group, and the expression of EBNA1 was higher in the untransfected group compared with the empty plasmid SFG group, which was statistically significant (P < 0.05); As shown in Figure 1, in vitro studies found that, compared to the untransfected group, the empty plasmid SFG group, the recombinant plasmid rv-ebna1/car group showed better killing efficacy on Raji cells, and the recombinant plasmid rv-ebna1/car group showed better killing efficacy on Raji cells compared to the empty plasmid SFG group; The tumor volumes of the rats in group C were larger compared with those in groups A and B, and the tumor volumes of the rats in group A were smaller compared with those in group B. The tumor volumes of the rats in group C were larger compared with those of the rats in the three groups (P<0.05). In group C, the cells were more severely invaded, and the nuclei were damaged. In group B, cell invasion in tissues was mild in the nucleus. The infection of cells in the tissues of rats in group A was better compared to groups B and C. In vitro experiments found that inhibition of EBNA1 was able to kill EBV-positive B cell lymphoid tumor cells effectively. Animal experiments found that ebna1-28t was able to shrink the volume as well as tumor weight of transplanted tumors in nude mice with EBV-positive B cell lymphoma and played a better inhibitory role.

Electrospun aligned poly(ε-caprolactone) nanofiber yarns guiding 3D organization of tendon stem/progenitor cells in tenogenic differentiation and tendon repair

Hierarchical anisotropy structure directing 3D cellular orientation plays a crucial role in designing tendon tissue engineering scaffolds. Despite recent development of fabrication technologies for controlling cellular organization and design of scaffolds that mimic the anisotropic structure of native tendon tissue, improvement of tenogenic differentiation remains challenging. Herein, we present 3D aligned poly (ε-caprolactone) nanofiber yarns (NFYs) of varying diameter, fabricated using a dry-wet electrospinning approach, that integrate with nano- and micro-scale structure to mimic the hierarchical structure of collagen fascicles and fibers in native tendon tissue. These aligned NFYs exhibited good in vitro biocompatibility, and their ability to induce 3D cellular alignment and elongation of tendon stem/progenitor cells was demonstrated. Significantly, the aligned NFYs with a diameter of 50 μm were able to promote the tenogenic differentiation of tendon stem/progenitor cells due to the integration of aligned nanofibrous structure and suitable yarn diameter. Rat tendon repair results further showed that bundled NFYs encouraged tendon repair in vivo by inducing neo-collagen organization and orientation. These data suggest that electrospun bundled NFYs formed by aligned nanofibers can mimic the aligned hierarchical structure of native tendon tissue, highlighting their potential as a biomimetic multi-scale scaffold for tendon tissue regeneration.

Evidence for Nonlinear Gluon Effects in QCD and Their Mass Number Dependence at STAR

The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π^{0}s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π^{0} pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale Q_{s}^{2} on the mass number A. A linear scaling of the suppression with A^{1/3} is observed with a slope of -0.09±0.01.

[MiR-372-5p regulates PI3K/AKT/CXCL12 signaling pathway by targeting PTEN to promote colorectal cancer cell metastasis]

OBJECTIVE

To investigate whether miR-372-5p regulates PI3K/AKT/CXCL12 signaling pathway by targeting PTEN to promote metastasis of colorectal cancer cells.

METHODS

We detected the differential expression of miR-372-5p using RT-qRCR in colorectal cancer and adjacent tissues, colorectal cancer cells and normal intestinal epithelial cells. Bioinformatic analysis and double luciferase assay were performed for verification of the targeting relationship between miR-372-5p and PTEN. Western blotting was used to assess the effects of transfection with miR-372-5p inhibitor and miR-372-5p mimics alone, co-transfection with miR-372-5p inhibitor and si-PTEN, and co-transfection with miR-372-5p mimics and PI3K inhibitor on the expressions of PTEN and CXCL12 and the activation of PI3K/AKT signal pathway; Transwell assay and scratch assay were used to examine the changes in the migration ability of the transfected cells, the cells co-transfected with miR-372-5p mimics and si-CXCL12, and the cells treated with conditioned medium from HCT116 cells transfected with miR-372-5p mimics.

RESULTS

The expression of miR-372-5p was significantly higher in colorectal cancer tissues than in adjacent tissues, and higher in HCT116 and SW620 cells than in NCM460 cells (P < 0.01). Double luciferase assay confirmed that PTEN was a potential target gene of miR-372-5p (P < 0.05). Transfection of HCT116 cells with miR-372-5p mimics obviously decreased PTEN protein expression, increase CXCL12 expression and the phosphorylation level of AKT, and lowered the cell migration ability, while transfection with miR-372-5p inhibitor produced the opposite effects (P < 0.05); si-PTEN obviously neutralized the effect of miR-372-5p inhibitor (P < 0.01). PI3K inhibitor significantly decreased CXCL12 expression and inhibited the cell migration (P < 0.05), and this effect was mitigated by miR-372-5p mimics (P < 0.01). Treatment with the conditioned medium from HCT116 cells transfected with miR-372-5p mimics significantly enhanced the migration ability of NCM460 cells, and this effect was suppressed by transfection with si-CXCL12 (P < 0.01).

CONCLUSION

MiR-372-5p activates PI3K/AKT signaling pathway by targeting PTEN and up-regulates CXCL12 expression to promoting metastasis of colorectal cancer cells.

Evaluation of safety and immunogenicity of duck-plague virus gC/gE double gene deletion

Duck plague caused by duck plague virus (DPV) is a highly contagious disease that can cause serious morbidity and death in waterfowl such as ducks and geese, and bring huge economic losses to the duck industry. In this study, on the basis of the duck plague virus gC gene deletion strain CHv-ΔgC, based on the duck plague virus bacterial artificial chromosome (BAC) platform in our laboratory, the gE gene was knocked out using the traceless deletion technology to obtain gC/gE double gene deletion candidate vaccine strain CHv-ΔgC/gE. The double gene deletion strain (CHv-ΔgC/gE) constructed in this study has greatly weakened virulence, no pathogenicity to ducks, and stable genetic characteristics in vitro and in vivo. Ducks immunized with CHv-ΔgC/gE can produce neutralizing antibodies and ELISA antibody levels comparable to those of commercial duck plague attenuated vaccine immunization, and can resist 100 LD₅₀ CHv challenge of ducks, with good immune protection effect. It has the potential to be further developed into duck plague gC/gE double gene deletion, marked attenuated vaccine.

The DHAV-1 protein VP1 interacts with PI3KC3 to induce autophagy through the PI3KC3 complex

Duck hepatitis A virus type 1 (DHAV-1) is one of the main pathogens responsible for death in ducklings. Autophagy is a catabolic process that maintains cellular homeostasis, and the PI3KC3 protein plays an important role in the initiation of autophagy. DHAV-1 infection induces autophagy in duck embryo fibroblasts (DEFs) but the molecular mechanism between it and autophagy has not been reported. First, we determined that DHAV-1 infection induces autophagy in DEFs and that autophagy induction is dependent on the integrity of viral proteins by infecting DEFs with UV-inactivated or heat-inactivated DHAV-1. Then, in experiments using the pharmacological autophagy inducer rapamycin and the autophagy inhibitor chloroquine, autophagy inhibition was shown to reduce intracellular and extracellular DHAV-1 genome copies and viral titres. These results suggest that autophagy activated by DHAV-1 infection in DEFs affects DHAV-1 proliferation and extracellular release. Next, we screened the autophagy-inducing effects of the DHAV-1 structural proteins VP0, VP3, and VP1 and found that all DHAV-1 structural proteins could induce autophagy in DEFs but not the full autophagic flux. Finally, we found that VP1 promotes protein expression of PI3KC3 and Beclin1 by western blot experiments and that VP1 interacts with PI3KC3 by co-immunoprecipitation experiments; moreover, 3-MA-induced knockdown of PI3KC3 inhibited VP1 protein-induced autophagy in DEFs. In conclusion, the DHAV-1 structural protein VP1 regulates the PI3KC3 complex by interacting with PI3KC3 to induce autophagy in DEFs.

Differential analysis of ergosterol function in response to high salt and sugar stress in Zygosaccharomyces rouxii

Zygosaccharomyces rouxii is an osmotolerant and halotolerant yeast that can participate in fermentation. To understand the mechanisms of salt and sugar tolerance, the transcription levels of Z. rouxii M 2013310 under 180 g/L NaCl stress and 600 g/L glucose stress were measured. The transcriptome analysis showed that 2227 differentially expressed genes (DEGs) were identified under 180 g/L NaCl stress, 1530 DEGs were identified under 600 g/L glucose stress, and 1278 DEGs were identified under both stress conditions. Then, KEGG enrichment analyses of these genes indicated that 53.3% of the upregulated genes were involved in the ergosterol synthesis pathway. Subsequently, quantitative PCR was used to verify the results, which showed that the genes of the ergosterol synthesis pathway were significantly upregulated under 180 g/L NaCl stress. Finally, further quantitative testing of ergosterol and spotting assays revealed that Z. rouxii M 2013310 increased the amount of ergosterol in response to high salt stress. These results highlighted the functional differences in ergosterol under sugar stress and salt stress, which contributes to our understanding of the tolerance mechanisms of salt and sugar in Z. rouxii.

Alphaherpesvirus glycoprotein E: A review of its interactions with other proteins of the virus and its application in vaccinology

The viral envelope glycoprotein E (gE) is required for cell-to-cell transmission, anterograde and retrograde neurotransmission, and immune evasion of alphaherpesviruses. gE can also interact with other proteins of the virus and perform various functions in the virus life cycle. In addition, the gE gene is often the target gene for the construction of gene-deleted attenuated marker vaccines. In recent years, new progress has been made in the research and vaccine application of gE with other proteins of the virus. This article reviews the structure of gE, the relationship between gE and other proteins of the virus, and the application of gE in vaccinology, which provides useful information for further research on gE.

The histone deacetylase SIRT6 promotes glycolysis through the HIF-1α/HK2 signaling axis and induces erlotinib resistance in non-small cell lung cancer

Erlotinib is a first-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). Overcoming erlotinib resistance is crucial to improve the survival of advanced non-small cell lung cancer (NSCLC) patients with sensitive EGFR mutations. It is also an important clinical problem that urgently needs a solution. In this study, we explored strategies to overcome erlotinib resistance from the perspective of energy metabolism. SIRT6 is a histone deacetylase. Here, we found that high expression of SIRT6 is associated with poor prognosis of lung adenocarcinoma, especially in EGFR-mutated NSCLC patients. The next cell experiment found that SIRT6 expression increased in erlotinib-resistant cells, and SIRT6 expression was negatively correlated with the sensitivity of NSCLC to erlotinib. Inhibition of SIRT6 promoted erlotinib-induced apoptosis in erlotinib-resistant cells, and glycolysis in drug-resistant cells was also inhibited. Functional studies have shown that SIRT6 increases glycolysis through the HIF-1α/HK2 signaling axis in drug-resistant cells and inhibits the sensitivity of NSCLC cells to erlotinib. In addition, the HIF-1α blocker PX478-2HCL attenuated the glycolysis and erlotinib resistance induced by SIRT6. More importantly, we confirmed the antitumor effect of SIRT6 inhibition combined with erlotinib in NSCLC-bearing mice. Our findings indicate that the cancer metabolic pathway regulated by SIRT6 may be a new target for attenuating NSCLC erlotinib resistance and has potential as a biomarker or therapeutic target to improve outcomes in NSCLC patients.

Global patterns and drivers of initial plant litter ash concentration

Ash is a fundamental component of plant litter and plays a vital role in regulating litter decomposition. However, to date, global patterns and underlying mechanisms of initial litter ash concentrations remain unclear. Here, we used 570 observations collected from 104 independent publications to assess the global patterns of initial plant litter ash concentrations and evaluated the effects of mycorrhizal association [arbuscular mycorrhiza (AM) vs. ectomycorrhiza (ECM)], taxon group (gymnosperm vs. angiosperm), life form (tree vs. shrub vs. herb), leaf type (broadleaf vs. needle), and environmental factors such as climate and soil properties on initial litter ash concentration. The results showed that (1) global average ash concentrations varied significantly among different plant tissues and were 7.3, 4.5, 3.7, 3.5, 3.1, 2.4, and 1.5% in leaf, root, bark, reproductive tissue (flower and fruit), branch, stem, and wood litter, respectively; (2) in leaf litter, the initial ash concentrations of AM plants and species associated with both AM and ECM fungi were higher than those of ECM plants, and those of the tree species were lower than those of the herbs and shrubs; in root litter, the initial ash concentrations of the AM plants were lower than those of the species associated with both AM and ECM fungi but higher than those of the ECM plants; in both leaf and root litter, the initial ash concentrations of the angiosperms and broadleaf trees were higher than those of the gymnosperms and needle trees, respectively, while the effect of plant traits on branch litter was not obvious; and (3) the initial ash concentration of leaf litter was predominantly driven by mycorrhizal association and taxon group, while that of root litter tended to be driven by mycorrhizal association well as soil organic carbon. Our study clearly assessed the global patterns and underlying mechanisms of initial plant litter ash concentrations, which could help in better understanding the role of ash in litter decomposition and the related processes of carbon and nutrient cycling.

The Evolution of BRAF Activation in Non-Small-Cell Lung Cancer

Non-small-cell lung cancer (NSCLC) is the most common subtype of lung cancer, of which approximate 4% had BRAF activation, with an option for targeted therapy. BRAF activation comprises of V600 and non-V600 mutations, fusion, rearrangement, in-frame deletions, insertions, and co-mutations. In addition, BRAF primary activation and secondary activation presents with different biological phenotypes, medical senses and subsequent treatments. BRAF primary activation plays a critical role in proliferation and metastasis as a driver gene of NSCLC, while secondary activation mediates acquired resistance to other targeted therapy, especially for epidermal growth factor tyrosine kinase inhibitor (EGFR-TKI). Treatment options for different activation of BRAF are diverse. Targeted therapy, especially two-drug combination therapy, is an important option. Besides, immune checkpoint inhibitors (ICIs) would be another option since BRAF activation would be a positive biomarker of tumor response of ICIs therapy. To date, no high level evidences support targeted therapy or immunotherapy as prioritized recommendation. After targeted therapy, the evolution of BRAF includes the activation of the upstream, downstream and bypass pathways of BRAF. In this review, therapeutic modalities and post-therapeutic evolutionary pathways of BRAF are discussed, and future research directions are also provided.

Epidemiological analysis of second primary malignant neoplasms in cancer survivors aged 85 years and older: a SEER data analysis (1975-2016)

Cancer burden in patients aged 85 years and older has rapidly increased accompanying the decrease in mortality, which is raising the concern of developing second primary malignant neoplasms (SPM). This study aimed to investigate the epidemiology of the SPM in this population in the US by using the surveillance, epidemiology, and end results database (1975-2016). The cumulative incidence of developing a SPM was calculated by the Fine and Gray model. Standardized incidence ratios (SIR) were calculated via Poisson regression. The relative post-SPM survival rate was calculated by the Kaplan-Meier method. Male patients with skin melanoma, kidney and renal pelvis and urinary bladder cancers had high cumulative incidences (15.32%, 13.55%, and 12.26%, respectively) and increased SIRs (1.47, 1.44, and 1.16, respectively) for developing SPMs. Female patients with skin melanoma and urinary bladder cancers had high cumulative incidences (10.18% and 7.87%, respectively) and increased SIRs (1.34 and 1.18, respectively). In general, the incidence of SPM cases increased over time. The median latency ranged from 17 to 37 months. A less than 50% of patients had 1-year post-SPM survival. In conclusion, some of these patients had an increased risk of the SPM, with poor survival.

MRI-based radiomics analysis in differentiating solid non-small-cell from small-cell lung carcinoma: a pilot study

AIM

To investigate the ability of a T2-weighted (W) magnetic resonance imaging (MRI)-based radiomics signature to differentiate solid non-small-cell lung carcinoma (NSCLC) from small-cell lung carcinoma (SCLC).

MATERIALS AND METHODS

The present retrospective study enrolled 152 eligible patients (NSCLC = 125, SCLC = 27). All patients underwent MRI using a 3 T scanner and radiomics features were extracted from T2W MRI. The least absolute shrinkage and selection operator (LASSO) logistic regression model was used to identify the optimal radiomics features for the construction of a radiomics model to differentiate solid NSCLC from SCLC. Threefold cross validation repeated 10 times was used for model training and evaluation. The conventional MRI morphology features of the lesions were also evaluated. The performance of the conventional MRI morphological features, and the radiomics signature model and nomogram model (combining radiomics signature with conventional MRI morphological features) was evaluated using receiver operating characteristic (ROC) curve analysis.

RESULTS

Five optimal features were chosen to build a radiomics signature. There was no significant difference in age, gender, and the largest diameter. The radiomics signature and conventional MRI morphological features (only pleural indentation and lymph node enlargement) were independent predictive factors for differentiating solid NSCLC from SCLC. The area under the ROC curves (AUCs) for MRI morphological features, and the radiomics model, and nomogram model was 0.69, 0.85, and 0.90 (ROC), respectively.

CONCLUSIONS

The T2W MRI-based radiomics signature is a potential non-invasive approach for distinguishing solid NSCLC from SCLC.

Duck Tembusu virus infection induces mitochondrial-mediated and death receptor-mediated apoptosis in duck embryo fibroblasts

Duck Tembusu virus (DTMUV) is a pathogenic flavivirus that has caused enormous economic losses in Southeast Asia. Our previous study showed that DTMUV could induce duck embryo fibroblast (DEF) apoptosis, but the specific mechanism was not clear. In this study, we confirmed that DTMUV could induce the apoptosis of DEFs by DAPI staining and TUNEL staining. Furthermore, we found that the expression levels of cleaved-caspase-3/7/8/9 were significantly upregulated after DTMUV infection. After treatment of cells with an inhibitor of caspase-8 or caspase-9, DTMUV-induced apoptosis rates were significantly decreased, indicating that the caspase-8-mediated death receptor apoptotic pathway and caspase-9-mediated mitochondrial apoptotic pathway were involved in DTMUV-induced apoptosis. Moreover, we found that DTMUV infection not only caused the release of mitochondrial cytochrome C (Cyt C) and the downregulation of the apoptosis-inhibiting protein Bcl-2 but also reduced the mitochondrial membrane potential (MMP) and the accumulation of intracellular reactive oxygen species (ROS). Key genes in the mitochondrial apoptotic pathway and death receptor apoptotic pathway were upregulated to varying degrees, indicating the activation of the mitochondrial apoptosis pathway and death receptor apoptosis pathway. In conclusion, this study clarifies the molecular mechanism of DTMUV-induced apoptosis and provides a theoretical basis for revealing the pathogenic mechanism of DTMUV infection.

A proposed disease classification system for duck viral hepatitis

The nomenclature of duck viral hepatitis (DVH) was historically not a problem. However, 14 hepatotropic viruses among 10 different genera are associated with the same disease name, DVH. Therefore, the disease name increasingly lacks clarity and may no longer fit the scientific description of the disease. Because one disease should not be attributed to 10 genera of viruses, this almost certainly causes misunderstanding regarding the disease-virus relationship. Herein, we revisited the problem and proposed an update to DVH disease classification. This classification is based on the nomenclature of human viral hepatitis and the key principle of Koch's postulates (“one microbe and one disease”). In total, 10 types of disease names have been proposed. These names were literately matched with hepatitis-related viruses. We envision that this intuitive nomenclature system will facilitate scientific communication and consistent interpretation in this field, especially in the Asian veterinary community, where these diseases are most commonly reported.

The autophagy-related degradation of MDA5 by Tembusu virus nonstructural 2B disrupts IFNβ production

Duck Tembusu virus (TMUV) is a serious avian pathogen causing a decline in egg production, but the mechanism of the virus that breaks through the innate immune system is poorly understood. Here, we show that TMUV inhibits poly(I:C)-induced interferon (IFN) production. Because poly(I:C) transfection can specifically activate the MDA5 pathway in duck primary cells, we found that infection with TMUV can specifically target MDA5 and lead to its degradation. MDA5 downregulation could be blocked by the autophagy inhibitor 3-methyladenine (3-MA) but not a proteasome inhibitor, strongly implicating MDA5 degradation as an autophagy-related degradation pathway. Pretreatment with 3-MA enhanced the expression of MDA5 and inhibited TMUV replication. To screen TMUV proteins that degraded MDA5, the TMUV replicon and MDA5-Flag were cotransfected into cells, and the western blot analysis showed that nonstructural 2B (NS2B) can degrade MDA5 in a dose-dependent manner. Dual-luciferase assays indicate that NS2B alone inhibits MDA5- or poly(I:C)-mediated IFN production. NS2B binds MDA5 in the presence of 3-MA. The deletion of the amino acids of NS2B from residues 51 to 92 (hydrophilic area) restored the expression of MDA5 and relieved the MDA5-mediated IFNβ production inhibition by NS2B, indicating that the hydrophilic area of NS2B is important for its interaction with host innate immunity.

Attenuated Duck Hepatitis A Virus Infection Is Associated With High mRNA Maintenance in Duckling Liver via m6A Modification

Host translation is generally modulated by viral infection, including duck hepatitis A virus (DHAV) infection. Previously, we reported that cellular protein synthesis in a cell model of duck embryo fibroblasts is significantly inhibited by DHAV infection but not viral proteins, suggesting that an important viral-host interaction occurs at the translational level. In this study, we aim to further understand the impact of DHAV virulence on cellular N6-methyladenosine (m6A) modification, which is essential to a wide variety of RNA biological processes, such as mRNA stabilization and translation. Using m6A antibody-based immunoprecipitation, m6A-seq, and LC–MS/MS, we observed that m6A-modified mRNA exists in both virulent and attenuated DHAV-infected duckling livers. Importantly, m6A levels in mRNA were much higher in attenuated DHAV-infected livers compared with virulent DHAV-infected livers, suggesting virulence-dependent regulation of m6A modification. Analysis of modification motifs indicated that GAAGAAG is the most enriched motif. Combined m6A-seq and RNA-seq data analysis indicated a generally positive correlation between m6A and mRNA expression levels in DHAV-infected duckling livers. GO analysis of genes with decreased or increased m6A levels showed that these genes were enriched in various terms, including oxidation–reduction processes and antiviral immune responses. Collectively, our work reveals DHAV virulence-dependent coordination between m6A modification and mRNA expression in duckling livers.

Duck Plague Virus Negatively Regulates IFN Signaling to Promote Virus Proliferation via JNK Signaling Pathway

Duck plague virus (DPV), a member of the alphaherpesvirus subfamily, can cause severe damage and immunosuppression in ducks and geese in China. Since lacking an available cell model, the antiviral signal transduction pathways induction and regulation mechanisms related to DPV infection in duck cells are still enigmatic. Our previous study developed a monocyte/macrophages cell model, which has been applied to study innate immunity with DPV. In the present study, we compared and analyzed transcriptome associated with the DPV infection of CHv (virulent strain) and CHa (avirulent strain) at 48hpi based on the duck monocyte/macrophages cell model and RNA-seq technology. Differentially expressed genes (DEGs) analysis showed 2,909 and 2,438 genes altered in CHv and CHa infected cells compared with control cells. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that the DEGs were mainly involved in biological processes such as metabolic pathways, viral infectious diseases, immune system, and signal transduction. The CHv and CHa virus differentially regulated MAPK, NF-κB, and IFN signaling pathways based on transcriptome sequencing data and RT-qPCR results. The JNK inhibitor SP600125 enhanced the IFN signaling, but potentially reduced the VSV and DPV titers in the cell culture supernatant, indicating that JNK negatively regulates the IFN pathway and the inflammatory pathway to promote virus proliferation. The research results may provide promising information to understand the pathogenesis of DPV and provide a novel mechanism by which DPV modulates antiviral signaling and facilitate virus proliferation through hijacking the JNK pathway, which provides a new means for the prevention and control of DPV infection.

Duck hepatitis A virus type 1 mediates cell cycle arrest in the S phase

Background

Duck hepatitis A virus type 1 (DHAV-1) is one of the most serious pathogens endangering the duck industry. However, there are few studies on the regulation of the cell cycle by DHAV-1.

Methods

In this study, flow cytometry was applied to analyze the effect of DHAV-1 infection on the cell cycle of duck embryo fibroblasts (DEFs). Subsequently, we analyzed the effects of cell cycle phases on DHAV-1 replication by real-time reverse transcriptase quantitative PCR (real-time RT-qPCR).

Results

Flow cytometry data analysis found that DEFs in the S phase increased by 25.85% and 54.21% at 24 h and 48 h after DHAV-1 infection, respectively. The levels of viral RNA detected by real-time RT-qPCR were higher in the DEFs with synchronization in the S phase or G0/G1 phase than in the control group. However, there was no difference in viral copy number between the G2/M phase arrest and control groups. In addition, non-structural protein 3D of DHAV-1 significantly increased cells in the S phase, indicating that 3D protein is one of the reasons for the cell cycle arrest in the S phase.

Conclusions

In summary, DHAV-1 infection induces the cell cycle arrest of DEFs in the S phase. Both S phase and G0/G1 phase synchronization facilitate the replication of DHAV-1, and 3D protein is one of the reasons for the S phase arrest.

Functions of Viroporins in the Viral Life Cycle and Their Regulation of Host Cell Responses

Viroporins are virally encoded transmembrane proteins that are essential for viral pathogenicity and can participate in various stages of the viral life cycle, thereby promoting viral proliferation. Viroporins have multifaceted effects on host cell biological functions, including altering cell membrane permeability, triggering inflammasome formation, inducing apoptosis and autophagy, and evading immune responses, thereby ensuring that the virus completes its life cycle. Viroporins are also virulence factors, and their complete or partial deletion often reduces virion release and reduces viral pathogenicity, highlighting the important role of these proteins in the viral life cycle. Thus, viroporins represent a common drug-protein target for inhibiting drugs and the development of antiviral therapies. This article reviews current studies on the functions of viroporins in the viral life cycle and their regulation of host cell responses, with the aim of improving the understanding of this growing family of viral proteins.

[Inhibition of Sonic Hedgehog signaling inhibits fibrous scar formation and adversely affects functional outcome after ischemic brain injury in rats]

OBJECTIVE

To investigate the effects of inhibiting Sonic Hedgehog (Shh) signaling on fibrous scar formation and functional outcome after ischemic brain injury.

METHODS

Adult SD rats were randomized into sham-operated group, middle cerebral artery occlusion (MCAO) and reperfusion (I/R) group, I/R with intraventricular empty adenoviral vector (rAd-NC) injection group, and I/R with adenovirus-mediated Shh knockdown (rAd-ShShh) group. After the treatments, the neurological deficits of the rats were assessed, and the protein and mRNA expressions of fibronectin (Fn), α-SMA, and Shh in the ischemic hemisphere were detected with immunofluorescence assay and qPCR; TUNEL staining was used for detecting neural cell apoptosis. In the cell experiment, primary meningeal fibroblasts isolated from neonatal SD rats were pretreated for 24 h with TGF-β1 or TGF-β1 plus cyclopamine (CYC) before oxygen-glucose deprivation for 150 min followed by reoxygenation for 72 h (OGD/R). CCK-8 assay and scratch test were performed to examine the changes in cell proliferation and migration, and immunofluorescence assay, qPCR and Western blotting were used for detecting cell transformation and the expressions of Shh, α-SMA, and Fn.

RESULTS

Cerebral I/R injury significantly increased the protein and mRNA expressions of Shh, α-SMA, and Fn in the ischemic hemisphere of the rats, but their expression levels were significantly lowered by intraventricular injection of rAd-Shshh (P < 0.05), which obviously increased cell apoptosis in the ischemic hemisphere (P < 0.05) and improved modified mNSS and modified Bederson scores of the rats (P < 0.05). In the cell experiment, pretreatment with TGF-β1 and TGF-β1+CYC both increased the viability of the primary meningeal fibroblasts after OGD/R. TGF-β1 significantly enhanced the migration ability and induced obvious transformation of the exposed cells (P < 0.05), but these effects were significantly attenuated by co-treatment with CYC (P < 0.05). The expressions of Shh, α-SMA and Fn in the TGF-β1 group were all significantly higher in TGF-β1-treated cells (P < 0.05) and were obviously lowered by co-treatment with CYC (P < 0.05).

CONCLUSION

Inhibition of Shh signaling may inhibit fibrous scar formation and functional recovery in rats after ischemic brain injury.

[Chaihu Guizhi Decoction plus or minus formula combined with capecitabine inhibits IL-6/STAT3 signaling to suppress triple-negative breast cancer xenografts in nude mice]

OBJECTIVE

To investigate the effect of Chaihu Guizhi Decoction (CHGZD) combined with capecitabine on growth and apoptosis of subcutaneous triple-negative breast cancer xenografts in nude mice and explore the possible mechanism.

METHODS

Nude mouse models bearing subcutaneous triple-negative breast cancer xenografts were randomized into 6 groups (n=10) for treatment with distilled water (model group), low (10.62 g/kg), medium (21.23 g/kg) and high (42.46 g/kg) doses of CHGZD, capecitabine (0.2 mg/kg), or the combination of CHGZD (42.46 g/kg) and capecitabine (0.2 mg/k) once daily for 21 consecutive days. The general condition of mice was observed, and after 21-day treatments, the tumors were dissected for measurement of tumor volume and weight and histopathological examination with HE staining. Serum IL-6 levels of the mice were determined with enzyme-linked immunosorbent assay (ELISA), and the expression levels of IL-6, STAT3, p-STAT3, Bax, Bcl-2 and cyclin D1 in the tumor tissues were detected using real-time PCR and Western blotting.

RESULTS

Compared with those in the model group, the tumor-bearing mice receiving treatments with CHGZD showed significantly increased food intake with good general condition, sensitive responses, increased body weight, and lower tumor mass (P < 0.01). Compared with capecitabine treatment alone, treatment with CHGZD alone at the medium and high doses and the combined treatment all resulted in significantly higher tumor inhibition rates (P < 0.01), induced obvious tumor tissue degeneration and reduced the tumor cell density. Treatments with CHGZD, both alone and in combination with capecitabine, significantly decreased serum IL-6 level, lowered the mRNA expression levels of IL-6 and STAT3, the protein expressions of IL-6, STAT3 and P-STAT3 (P < 0.05), and the mRNA and protein expressions of Bcl-2 and cyclin D1 (P < 0.05), and increased the mRNA and protein expressions of Bax in the tumor tissues (P < 0.05).

CONCLUSION

CHGZD combined with capecitabine can significantly inhibit tumor growth in nude mice bearing triple-negative breast cancer xenografts, the mechanism of which may involve the inhibition of IL-6/STAT3 signaling pathway and regulation of Bax, Bcl-2 and cyclin D1 expressions to suppress tumor cell proliferation and differentiation and induce cell apoptosis.

E2F7/8 is involved in cardiomyocyte polyploidy but does not affect myocardial reperfusion injury recovery

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): CSC fellowship

Background

Polyploidy cells consist of more than two complete sets of homologous chromosomes. Although a characteristic feature of cardiomyocytes and observed in all mammalian species, its molecular mechanism and biological functions are still unknown. Cardiomyocytes polyploidy in rodents occurs mainly through incomplete cytokinesis and increases with age. Studies have demonstrated that E2F7/8 transcription factors are key regulators of polyploidy in the liver and pancreas, however, it remains unclear if E2F7/8 control the generation of polyploidy cardiomyocytes and what the functional consequence is post-myocardial infarction (MI).

Methods

By using a tamoxifen inducible Cre/LoxP approach in new-born mice, we deleted E2F7/8 transcription factors ubiquitously and evaluated the biological significance of postnatal E2F7/8 loss. Mice underwent myocardial ischemia reperfusion injury (IRI) and heart function was assessed by 4D-echocardiography. Cardiomyocyte nucleus polyploidy was measured by FACS and microscope.

Results

Deficiency of E2F7/8 significantly suppress cardiomyocyte mononucleated and multinucleated polyploidy, as well as dramatically decreased hepatocytes polyploidy. E2F7/8 defect also led to a decrease in cardiac stress related marker lever such as ANP, BNP, MMP2, β-MHC/α-MHC and an increase in CD31 expression level. Surprisingly, E2F7/8 deletion did not have impact on cardiac function and dimensions post-IRI.

Conclusion

In summary, we identified that E2F7/8 activity is involved in the cellular polyploidy in the heart but did not affect myocardial function after myocardial injury.

Features and Functions of the Conserved Herpesvirus Tegument Protein UL11 and Its Binding Partners

The herpesvirus UL11 protein is encoded by the UL11 gene and is a membrane-anchored protein with multiple functions. In the last stage of viral replication, UL11 participates in the secondary envelopment process. It also plays a key role in primary envelopment, the transportation of newly assembled viral particles through cytoplasmic vesicles, and virion egress from the cell. UL11 is an important accessory protein and sometimes cooperates with other proteins that participate in virus-induced cell fusion. Cell fusion is necessary for cell-to-cell transmissions. This review summarizes the latest literature and discusses the roles of UL11 in viral assembly, primary and secondary envelopment, and cell-to-cell transmission to obtain a better understanding of the UL11 protein in the life cycle of herpesviruses and to serve as a reference for studying other viruses. Additionally, some recently discovered characteristics of UL11 are summarized.

The substitution at residue 218 of the NS5 protein methyltransferase domain of Tembusu virus impairs viral replication and translation and may triggers RIG-I-like receptor signaling

Flavivirus RNA cap-methylation plays an important role in viral infection, proliferation, and escape from innate immunity. The methyltransferase (MTase) of the flavivirus NS5 protein catalyzes viral RNA methylation. The E218 amino acid of the NS5 protein MTase domain is one of the active sites of flavivirus methyltransferase. In flaviviruses, the E218A mutation abolished 2’-O methylation activity and significantly reduced N-7 methylation activity. Tembusu virus (TMUV, genus Flavivirus) was a pathogen that caused neurological symptoms in ducklings and decreased egg production in laying ducks. In this study, we focused on a comprehensive understanding of the effects of the E218A mutation on TMUV characteristics and the host immune response. E218A mutation reduced TMUV replication and proliferation, but did not affect viral adsorption and entry. Based on a TMUV replicon system, we found that the E218A mutation impaired viral translation. In addition, E218A mutant virus might be more readily recognized by RIG-I-like receptors to activate the corresponding antiviral immune signaling than WT virus. Together, our data suggest that the E218A mutation of TMUV MTase domain impairs viral replication and translation and may activates RIG-I-like receptor signaling, ultimately leading to a reduction in viral proliferation.

Identification of duck GSDME: Tissue distribution, proteolysis and cellular location

Gasdermin E (GSDME) is a member of the gasdermin family. Cleavage of mammalian GSDME by apoptotic caspases or granzyme proteases liberates the N-terminal effector domain (GSDME-N), which is capable of forming membrane pores and executing inflammation and cell death. Herein, duck GSDME was first cloned with a total length of 1500 bp and encoding 499 amino acids (aa), which is most evolutionally related to the chicken GSDME. The tissue-distribution profiles of GSDME showed that relatively high levels of GSDME mRNA were detected in immune tissues of duckling and adult ducks. Additionally, GSDME mRNA was significantly upregulated in duck primary embryo fibroblasts (DEFs) and duck primary ovary cells after duck Tembusu virus (DTMUV) infection. Intriguingly, when duck caspase-3 was coexpressed, the duck GSDME produced two GSDME-N fragments with molecular weights of 25 kDa and 30 kDa. Furthermore, both GSDME and cleaved GSDME were observed to be located in the cytoplasm by indirect immunofluorescence assay (IFA). Taken together, our research data show that duck GSDME has similar biological characteristics to mammals. These findings highlight the role of duck GSDME in TMUV infection, indicating that cooperation between GSDME and caspase-3 promotes the proteolytic process.

Measurements of Proton High-Order Cumulants in sqrt[s_{NN}]=3 GeV Au+Au Collisions and Implications for the QCD Critical Point

We report cumulants of the proton multiplicity distribution from dedicated fixed-target Au+Au collisions at sqrt[s_{NN}]=3.0  GeV, measured by the STAR experiment in the kinematic acceptance of rapidity (y) and transverse momentum (p_{T}) within -0.5<y<0 and 0.4<p_{T}<2.0  GeV/c. In the most central 0%-5% collisions, a proton cumulant ratio is measured to be C_{4}/C_{2}=-0.85±0.09 (stat)±0.82 (syst), which is 2σ below the Poisson baseline with respect to both the statistical and systematic uncertainties. The hadronic transport UrQMD model reproduces our C_{4}/C_{2} in the measured acceptance. Compared to higher energy results and the transport model calculations, the suppression in C_{4}/C_{2} is consistent with fluctuations driven by baryon number conservation and indicates an energy regime dominated by hadronic interactions. These data imply that the QCD critical region, if created in heavy-ion collisions, could only exist at energies higher than 3 GeV.

Measurements of _{Λ}^{3}H and _{Λ}^{4}H Lifetimes and Yields in Au+Au Collisions in the High Baryon Density Region

We report precision measurements of hypernuclei _{Λ}^{3}H and _{Λ}^{4}H lifetimes obtained from Au+Au collisions at sqrt[s_{NN}]=3.0  GeV and 7.2 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider, and the first measurement of _{Λ}^{3}H and _{Λ}^{4}H midrapidity yields in Au+Au collisions at sqrt[s_{NN}]=3.0  GeV. _{Λ}^{3}H and _{Λ}^{4}H, being the two simplest bound states composed of hyperons and nucleons, are cornerstones in the field of hypernuclear physics. Their lifetimes are measured to be 221±15(stat)±19(syst)  ps for _{Λ}^{3}H and 218±6(stat)±13(syst)  ps for _{Λ}^{4}H. The p_{T}-integrated yields of _{Λ}^{3}H and _{Λ}^{4}H are presented in different centrality and rapidity intervals. It is observed that the shape of the rapidity distribution of _{Λ}^{4}H is different for 0%-10% and 10%-50% centrality collisions. Thermal model calculations, using the canonical ensemble for strangeness, describes the _{Λ}^{3}H yield well, while underestimating the _{Λ}^{4}H yield. Transport models, combining baryonic mean-field and coalescence (jam) or utilizing dynamical cluster formation via baryonic interactions (phqmd) for light nuclei and hypernuclei production, approximately describe the measured _{Λ}^{3}H and _{Λ}^{4}H yields. Our measurements provide means to precisely assess our understanding of the fundamental baryonic interactions with strange quarks, which can impact our understanding of more complicated systems involving hyperons, such as the interior of neutron stars or exotic hypernuclei.

RNA-Seq analysis of duck embryo fibroblast cells gene expression during duck Tembusu virus infection

Duck Tembusu virus (DTMUV), a member of the family Flaviviridae and an economically important pathogen with a broad host range, leads to markedly decreased egg production. However, the molecular mechanism underlying the host-DTMUV interaction remains unclear. Here, we performed high-throughput RNA sequencing (RNA-Seq) to study the dynamic changes in host gene expression at 12, 24, 36, 48 and 60 h post-infection (hpi) in duck embryo fibroblasts (DEF) infected with DTMUV. A total of 3129 differentially expressed genes (DEG) were identified after DTMUV infection. Gene Ontology (GO) category and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that these DEG were associated with multiple biological functions, including signal transduction, host immunity, virus infection, cell apoptosis, cell proliferation, and pathogenicity-related and metabolic process signaling pathways. This study analyzed viral infection and host immunity induced by DTMUV infection from a novel perspective, and the results provide valuable information regarding the mechanisms underlying host-DTMUV interactions, which will prove useful for the future development of antiviral drugs or vaccines for poultry, thus benefiting the entire poultry industry.

Evaluation of the Safety and Immunogenicity of Duck-Plague Virus gE Mutants

Duck plague (DP) is an acute infectious disease in the duck industry. The duck plague virus (DPV) is the pathogen, a subfamily of alphaherpesvirinae. gE is a type I membrane protein that contains three parts: an extracellular domain, a transmembrane domain, and a cytoplasmic domain. gE is the major virulence determinant of α-herpesvirus. However, the functions of the gE extracellular and cytoplasmic domains have not been reported in DPV. In this study, a gE extracellular domain deletion mutant and a gE cytoplasmic domain deletion mutant were constructed from DPV. Virus replication kinetics showed that the growth titers of both the gE ectodomain-deleted mutant virus and the gE cytoplasmic domain-deleted virus in DEFs were lower than that of the parental virus CHv-50. DPV CHv-gEΔET and DPV CHv-gEΔCT were continuously passed to the 20th passage in DEFs and the 10th in ducklings. The mutant virus DNA after passage was extracted for identification. The results showed that the gE ectodomain and gE cytoplasmic domain deletion mutant viruses have good genetic stability. The ducklings in each group (n=10) were inoculated with the same titers of DPV CHv-gEΔET, DPV CHv-gEΔCT, DPV CHv-ΔgE, and parental CHv-50, respectively. Clinical symptoms and serum antibody levels were detected after inoculation. The results showed that the virulence of DPV CHv-gEΔCT to ducklings was reduced compared with parental CHv-50, while the virulence of DPV CHv-gEΔET to ducklings was significantly reduced. 10⁵ TCID₅₀ DPV CHv-gEΔET or DPV CHv-ΔgE can induce ducklings to produce DPV-specific antibodies, protect the ducklings from virulent CHv challenge. Therefore, DPV CHv-gEΔET may serve as a promising vaccine candidate to prevent and control duck plague.

Gemcitabine Combined with Cisplatin Has a Better Effect in the Treatment of Recurrent/Metastatic Advanced Nasopharyngeal Carcinoma

Objective

To explore the efficacy and safety of gemcitabine (GEM) combined with cisplatin (DDP) in the treatment of recurrent/metastatic nasopharyngeal carcinoma (NPC).

Methods

A total of 100 patients with recurrent/metastatic NPC treated in the First Affiliated Hospital, Hengyang Medical School, University of South China from January 2018 to March 2020 were retrospectively enrolled. Based on different chemotherapy schemes, they were assigned to an observation (Obs) group (DDP + GEM, n = 55) and a control (Con) group [DDP + FU (fluorouracil), n = 45]. The two groups were compared regarding the following items: therapeutic efficacy; serum levels of platelet-derived growth factor-BB (PDGF-BB), soluble epithelial cadherin (SE-CAD), and inflammation-related factors before and after treatment; toxic and side effects; 1-year survival rate; and quality of life (QOL) 6 months after treatment.

Results

The Obs group outperformed the Con group in therapeutic efficacy (P < 0.05). There were no significant differences in the levels of PDGF-BB, SE-CAD, interleukin (IL)-6, IL-10 and tumor necrosis factor (TNF)-α between the two groups before treatment (P > 0.05). After treatment, better improvements in PDGF-BB, SE-CAD and inflammatory factors were observed in the Obs group (P < 0.05). The toxic and side effects were significantly lower and the 1-year survival rate and patients' QOL after 6 months of treatment were significantly higher in the Obs group compared with the Con group (P < 0.05).

Conclusion

GEM combined with DDP can provide more clinical benefits for patients with recurrent/metastatic advanced NPC, with less side effects, high tolerance and significant efficacy, which can be further promoted in clinical use.

Age-related risk for second breast cancer and gynecological malignant neoplasms after differentiated thyroid cancer

PURPOSE

In this study, we aimed to investigate the age-related risk of second breast cancer (SBC) and second gynecological malignant neoplasms (SGMNs) in female differentiated thyroid cancer (DTC) survivors by utilizing the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

A total number of 55,622 female DTC patients were identified between 1975 and 2016, including 2168 patients who developed SBC and SGMNs. The Fine and Gray model was used to calculate the cumulative incidence and sub-distribution hazards ratios (SHR). Poisson regression analysis was employed to calculate the relative risk (RR) and standardized incidence ratio (SIR). Kaplan-Meier survival and log-rank test analyses were also performed.

RESULTS

The overall 40-year cumulative incidence of SBC and SGMNs was 18.9%. Their incidence in the adolescent and young adults (AYA) group increased slowly in the first 30 years, but then was rapidly elevated in the last decade. It increased gradually in the middle-aged adults group and in the first 25 years in the older adults group, but it scarcely increased thereafter. Both the middle-aged adults (adjusted SHR, 2.09; RR, 1.76) and the older adults (adjusted SHR, 1.32; RR, 1.58) groups had higher risks of developing combined SBC and SGMNs than the AYA group. The risks increased mainly in the early latency period. The three groups also had higher SIRs than the US general population. Besides, the best survival after SBC and SGMNs was observed in the AYA group.

CONCLUSIONS

Age was an independent risk factor for SBC and SGMNs incidences among female DTC survivors.