The Vif protein of caprine arthritis encephalitis virus inhibits interferon production.

Caprine arthritis-encephalitis (CAE) is a chronic progressive infectious disease caused by caprine arthritis-encephalitis virus (CAEV) that seriously threatens the goat industry. Chronic infection and life-long multi-tissue inflammation are the typical features of the disease. Innate antiviral immunity is essential for the host defense system that rapidly recognizes and eliminates invading viruses. Interferon ß (IFN-ß) is important for innate immunity and regulates immunity against a broad spectrum of viruses. To investigate the details of the IFN-ß response to CAEV infection, the effects of six viral proteins and the molecular mechanisms by which they affect IFN-ß production were analyzed. Overexpression of DU and Vif promote virus proliferation and inhibit the production of IFN-ß. qRT-PCR and luciferase reporter assays showed that overexpression of Vif inhibits the expression of luciferase under the control of the ISRE, NF-κB or IFN-ß promoter but does not affect the expression of IFN-ß activated by IRF3, indicating that Vif negatively regulates IFN-ß production by affecting upstream signal transduction of IRF3. Amino acids 149-164 of Vif were found to be necessary for the inhibitory effect of IFN-ß production. Our results indicate that CAEV evades surveillance and clearance by intracellular innate immunity by downregulating IFN-ß production.

SUMOylation of DDX39A Alters Binding and Export of Antiviral Transcripts to Control Innate Immunity.

The RNA helicase DDX39A plays an important role in the RNA splicing/export process. In our study, human DDX39A facilitated RNA virus escape from innate immunity to promote virus proliferation by trapping TRAF3, TRAF6, and MAVS mRNAs in the HEK293T cell nucleus. DDX39A was a target for SUMOylation. SUMO1, 2, and 3 modifications were found on immunoprecipitated DDX39A. However, only the SUMO1 modification decreased in vesicular stomatitis virus-infected HEK293T cells. Further studies have found that viral infection reduced SUMO1 modification of DDX39A and enhanced its ability to bind innate immunity-associated mRNAs by regulating the abundance of RanBP2 with SUMO1 E3 ligase activity. RanBP2 acted as an E3 SUMO ligase of DDX39A, which enhanced SUMO1 modification of DDX39A and attenuated its ability to bind RNA. This work described that specific mRNAs encoding antiviral signaling components were bound and sequestered in the nucleus by DDX39A to limit their expression, which proposed a new protein SUMOylation model to regulate innate immunity in viral infection.

Different Expression Characteristics of LAG3 and PD-1 in Sepsis and Their Synergistic Effect on T Cell Exhaustion: A New Strategy for Immune Checkpoint Blockade.

The impairment of immunity characterized by T cell exhaustion is the main cause of death in patients with sepsis after the acute phase. Although PD-1 blockade is highly touted as a promising treatment for improving prognosis, the role of PD-1 plays in sepsis and particularly its different roles in different periods are still very limited. A recent study revealed LAG3 can resist the therapeutic effect of PD-1 blockade in tumor, which inspired us to understand their role in sepsis. We enrolled 26 patients with acute sepsis from 422 candidates using strict inclusion criteria. Follow-up analysis revealed that the expression levels of PD-1 were rapidly increased in the early stage of sepsis but did not change significantly as infection continued (P < 0.05). However, the expression of LAG3 was contrary to that of PD-1. Compared with LAG3 or PD-1 single-positive T cells, T cells coexpressing LAG3 and PD-1 were significantly exhausted (P < 0.05). The proportion of coexpressing T cells was negatively correlated with the total number of lymphocytes (r = -0.653, P = 0.0003) and positively correlated with the SOFA score (r = 0.712, P < 0.0001). In addition, the higher the proportion of coexpressing T cells was, the longer the hospital stay and the higher the mortality. These results showed that LAG3 and PD-1 had a potential synergistic effect in regulating the gradual exhaustion of T cells in sepsis, which seriously affected the clinical prognosis of patients. Therefore, LAG3 and PD-1 double-positive T cells are an important indicator for immunity detection and prognostic evaluation. In the future, precision therapy may pay more attention to the different expression patterns of these two molecules.

Nonviral infection-related lymphocytopenia for the prediction of adult sepsis and its persistence indicates a higher mortality.

Sepsis is a life-threatening disease that affects 30 million people worldwide each year. Despite the rapid advances in medical technology and organ support systems, it is still difficult to reduce the mortality rate. Early and rapid diagnosis is crucial to improve the treatment outcome. The aim of this study was to investigate the prediction efficiency of lymphopenia and other clinical markers, such as white blood cell (WBC), neutrophil count (N#), procalcitonin (PCT), and arterial lactic acid (Lac) in the diagnosis and prognosis assessment for adult patients with nonviral infection-related sepsis.A total of 77 sepsis- and 23 non-sepsis adult patients were enrolled in this study from September 2016 to September 2018. Daily lymphocyte count (Lym) of the patients was calculated until discharge or death. The diagnostic performance of the Lym and other biomarkers were compared using the area under the receiver operating characteristic curve (ROC) value.The level of Lym was decreased significantly in the sepsis group. Lym had a high diagnostic performance for sepsis, with an area under the curve (AUC) value of 0.971 (95% CI = 0.916-0.994). The diagnostic efficacy of Lym was more significant than WBC, N#, and PCT (P < .001). The results showed that the 28-day mortality rate of patients with continuous Lym <0.76 × 10/L was 39.66%, which significantly higher than patients without persistent lymphocytopenia.Lym is a promising, low cost, fast, and easily available biomarker for the diagnosis of sepsis. When nonviral infection is suspected and lymphocytopenia level is lower than the optimal cut-off (0.76 × 10/L) value, high vigilance is required for sepsis. The persistence with the lymphocytopenia cut-off value (<0.76 × 10/L) >3 days indicates a higher 28-day mortality rate.

PEDV nsp16 negatively regulates innate immunity to promote viral proliferation.

Type-I IFNs (IFN-I) provide a key mediator of innate antiviral response during virus proliferation. Porcine epidemic diarrhea virus (PEDV), which causes diarrhea in swine of all ages, is a worldwide-distributed alphacoronavirus with economic importance. Here, we screened PEDV RNA modification enzymes involved in regulating antiviral response. Whereas the PEDV nsp13 barely regulates type I IFN, inflammatory cytokines (IL-6, TNF-a) and MHCII, nsp16 and nsp14 (to a lesser extent) down-regulate these antiviral effectors. Importantly, we found nsp16 KDKE tetrad appears to play a key role in interferon inhibition by mutating the D129 catalytic residue. Mechanistically, nsp16 down-regulates the activities of RIG-I and MDA5 mediated IFN-ß and ISRE. In turn, the mRNA levels of IFIT family members (IFIT1, IFIT2, IFIT3) was inhibited in cells overexpressing nsp16. In addition, nsp10 enhanced the inhibitory effect of nsp16 on IFN-ß. Altogether these results indicate PEDV nsp16 negatively regulates innate immunity to promote viral proliferation. Findings from this study provides novel perspective to advance the understanding in the pathogenesis of PEDV.

The alternatively spliced porcine FcγRI regulated PRRSV-ADE infection and proinflammatory cytokine production.

Receptors for the Fc region of IgG (FcγRs) play a key role in protecting the immune system and host from infection. In this study, we described the cloning, sequencing and characterization of porcine FcγRI, and reported six different FcγRI isoforms, four of which have never been reported before. Further analysis revealed that FcγR isoforms are generated by alternative splicing mechanisms, including two membrane isoforms and four soluble isoforms. Importantly, we found FcγRI splice variants differentially influence PRRSV antibody-dependent enhancement (ADE) effects. Membrane pCD64-T1 promotes endocytosis of the PRRSV-antibody complex to enhance PRRSV replication, and soluble pCD64-T3 has no ADE effect on PRRSV proliferation, but shows an inflammation enhancement effect. The differential expression of selective splicing in primary PAM cells and 3D4/21 cell lines are altered and regulated by PRRSV infection and inflammatory environment. Our results indicated that porcine FcγRI plays dual regulatory roles in PRRSV multiplication and PRRSV inflammation process by the alternatively spliced mechanism, which will be a new target in PRRSV prevention and control.

Discovery of Nonpeptide, Reversible HER1/HER2 Dual-Targeting Small-Molecule Inhibitors as Near-Infrared Fluorescent Probes for Efficient Tumor Detection, Diagnostic Imaging, and Drug Screening.

The abnormal expression of epidermal growth factor receptors HER1(EGFR) and HER2 is strongly associated with cancer invasion, metastasis, and angiogenesis. Their molecular detection is mainly executed using genetically encoded or antibody-based diagnostic tracers, but no dual-targeting small-molecule bioprobe has been achieved. Here, we report the novel small-molecule fluorescent probes Cy3-AFTN and Cy5-AFTN as potent dual-targeting inhibitors for efficient detection of HER1/HER2 expression in cancer cells and in vivo tumor diagnostic imaging. Unlike the irreversible HER1/HER2 inhibitors, Cy3-AFTN and Cy5-AFTN were designed as reversible/noncovalent probes based on the clinical drug afatinib, by making the molecule structurally impossible for receptor-mediated Michael additions. The synthesized probes were validated with live cell fluorescence imaging, flow cytometry and confocal-mediated competitive binding inhibition, molecular docking study, and in vivo xenograft tumor detection. The probes are competitively replaceable by other HER1/HER2 inhibitors; thus, they are potentially useful in fluorometric high-throughput screening for drug discovery.

The Immunological Regulation Roles of Porcine ß-1, 4 Galactosyltransferase V (B4GALT5) in PRRSV Infection.

B4GALT5, also known as ß-1, 4 galactosyltransferase V, is one of the members of ß-1, 4 galactosyltransferase gene (B4GALT) family, which was concerned with embryonic development, tumor generation, other malignant diseases. In this study, we firstly cloned porcine B4GALT (pB4GALT5) from porcine alveolar macrophages, and predicted the structural domain and function of seven porcine ß-1, 4 galactosyltransferase (I-VII) based on transcriptome analysis of PRRSV infected cells. Additionally, the upregulated porcine B4GALT5 expression was detected from PRRSV infected porcine alveolar macrophage (PAM) cells. The PRRSV proliferation were slightly inhibited in overexpression of pB4GALT5 transfected cells, the interaction of B4GALT5 and GP5 of PRRSV was firstly be detected by Co-IP, and the co-location between B4GALT5 and GP5 were also observed in golgi membranes by confocal microscopy. A significant increasing mRNA transcription, including inflammatory cytokines (IFN-α, IL-6, IL-18, IL-1ß, TNF-α) and some cell surface glycosylated protein involved in antigen present (MHC-I/II), cell adhesion and migration (chemokine MCP-1 and receptor CCR2; LFA-1, ICAM-1) were upregulated in B4GALT5 overexpressed PRRSV infected cells. Our results demonstrated that the regulation of pB4GALT5 plays an important roles in PRRSV proliferation and modification function in viral infection cells. And these results will make achievements by supporting the research of latent mechanisms of ß-1, 4 galactosyltransferase V in antiviral immunity.

The Superimposed Deubiquitination Effect of OTULIN and Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Nsp11 Promotes Multiplication of PRRSV.

Linear ubiquitination plays an important role in the regulation of the immune response by regulating nuclear factor κB (NF-κB). The linear ubiquitination-specific deubiquitinase ovarian tumor domain deubiquitinase with linear linkage specificity (OTULIN) can control the immune signaling transduction pathway by restricting the Met1-linked ubiquitination process. In our study, the porcine OTLLIN gene was cloned and deubiquitin functions were detected in a porcine reproductive and respiratory syndrome virus (PRRSV)-infected-cell model. PRRSV infection promotes the expression of the OTULIN gene; in turn, overexpression of OTULIN contributes to PRRSV proliferation. There is negative regulation of innate immunity with OTULIN during viral infection. The cooperative effects of swine OTULIN and PRRSV Nsp11 potentiate the ability to reduce levels of cellular protein ubiquitin associated with innate immunity. Importantly, PRRSV Nsp11 recruits OTULIN through a nonenzymatic combination to enhance its ability to remove linear ubiquitination targeting NEMO, resulting in a superimposed effect that inhibits the production of type I interferons (IFNs). Our report presents a new model of virus utilization of the ubiquitin-protease system in vivo from the perspective of the viral proteins that interact with cell deubiquitination enzymes, providing new ideas for prevention and control of PRRSV.IMPORTANCE Deubiquitination effects of swine OTULIN were identified. The interaction between porcine OTULIN and PRRSV Nsp11 is dependent on the OTU domain. PRRSV Nsp11 recruits OTULIN through a nonenzymatic combination to promote removal of linear ubiquitination targeting NEMO, resulting in a superimposed effect that inhibits the production of type I IFNs.

Evaluation of carotid artery elasticity in patients with uremia by echo tracking.

PURPOSE: The purpose of this study was to compare the carotid artery wall elasticity between patients with uremia and controls using echo tracking (ET). METHODS: Ninety-three patients with uremia and 35 control subjects (Group A) were enrolled in this study. In the ET mode, the carotid artery elasticity parameters including stiffness index (ß), pressure-strain elasticity modulus (EP), arterial compliance (AC), and one-point pulse wave velocity (PWVß) were measured, and carotid intima-media thickness (IMT) was measured with B-mode ultrasonography. The patients were classified into three groups: Group B (normal IMT), Group C (thickened IMT), and Group D (one single atheroma plaque). RESULTS: ß, EP, and PWVß were significantly higher in Group B, C, and D (especially in group D) than those of the control group (P < 0.05), and there were significant differences between Group A and Group B, while AC was lower than in controls, but there were no statistically significant differences among the four groups. CONCLUSIONS: ET is a noninvasive method that can demonstrate a loss in carotid artery elasticity in uremia patients with normal IMT.

Dual Regulation of Host TRAIP Post-translation and Nuclear/Plasma Distribution by Porcine Reproductive and Respiratory Syndrome Virus Non-structural Protein 1α Promotes Viral Proliferation.

In this study, we show that porcine reproductive and respiratory syndrome virus (PRRSV) non-structural protein 1α (nsp1α) facilitates PRRSV escape from innate immune by modulating nuclear to cytoplasmic translocation and distribution ratio of TRAIP to promote virus proliferation. Mechanistically, TRAIP interacts with PRRSV nsp1α via its K205 site, while NSP1α decreases the SUMOylation and K48 ubiquitination independent of the TRAIP interaction K205 site. Modulation of the dual modification of TRAIP by PRRSV nsp1α results in over-enrichment of TRAIP in the cytoplasm. Enrichment of nsp1α-induced cytoplasmic TRAIP in turn leads to excessive K48 ubiquitination and degradation of serine/threonine-protein kinase (TBK1), thereby antagonizing TBK1-IRF3-IFN signaling. This study proposes a novel mechanism by which PRRSV utilizes host proteins to regulate innate immunity. Findings from this study provides novel perspective to advance our understanding in the pathogenesis of PRRSV.

Evaluation of Right Ventricular Systolic Function in Patients With Chronic Pulmonary Heart Disease by 2-Dimensional Speckle-Tracking Echocardiography.

OBJECTIVES: To investigate the value of 2-dimensional (2D) speckle-tracking echocardiography for assessing right ventricular (RV) systolic function in patients with chronic pulmonary heart disease (CPHD) and the correlation of its parameters with the right ventricular ejection fraction (RVEF) on cardiac magnetic resonance imaging (MRI). METHODS: According to pulmonary arterial systolic pressure, 80 patients with CPHD and tricuspid regurgitation were divided into 2 groups: 42 with mild pulmonary hypertension (PH; 30-50 mm Hg) and 38 with moderate or severe PH (≥50 mm Hg); 41 control participants were recruited. All participants underwent 2D speckle-tracking echocardiography and cardiac MRI. The longitudinal peak systolic strain and longitudinal peak systolic strain rate were measured by echocardiography in each segment of the RV free wall and interventricular septum and compared with the RVEF on cardiac MRI. RESULTS: Strain values in all segments of the RV free wall and interventricular septum were lower in the mild PH group than the control group (P < .05). Strain rate values in the apical segment of the RV free wall and basal segment of the interventricular septum were lower in the mild PH group than the control group (P< .05). Strain and strain rate values in all segments of the RV free wall and interventricular septum were lower in the moderate or severe PH group than the control group (P < .05). Strain and strain rate values in all segments of the RV free wall and interventricular septum were lower in the moderate or severe PH group than the mild PH group (P< .05). Strain and strain rate values in all segments of the RV free wall and the interventricular septum correlated with the RVEF (P < .001). CONCLUSIONS: The ability of speckle-tracking echocardiography to directly monitor RV myocardial function may allow early sensitive detection of subclinical myocardial dysfunction in patients with CPHD, with better risk stratification and timely institution of therapy.

Evaluation of Left Ventricular Regional Systolic Function Using Tissue Doppler Echocardiography After Mesenchymal Stem Cell Transplantation in Rabbits With Myocardial Infarction.

OBJECTIVES: The aim of this work was to assess left ventricular (LV) regional systolic function in rabbits with myocardial infarction after allogeneic mesenchymal stem cell (MSC) transplantation using quantitative tissue velocity imaging. METHODS: Thirty New Zealand White rabbits were assigned into 3 groups randomly: a sham-operated group (n = 10), a myocardial infarction (MI) group (n = 10), and a MSC transplantation group (n = 10). Mesenchymal stem cells (1 × 10(7) in total) were delivered into 5 spots around the left anterior descending artery (LAD) blood supply area via direct intramyocardial injections 1 hour after LAD ligation in the MSC group, whereas the MI group received the same amount of phosphate-buffered saline injections. Echocardiography was performed before LAD ligation and 1 day and 2 weeks after MSC transplantation, respectively. The peak systolic velocity (Vs) of each LV wall segment was measured. The myocardial slices were harvested for histologic staining after the last echocardiographic examination. RESULTS: The velocity curves for the LV myocardium before LAD ligation had a trend showing that the Vs value decreased gradually from basal to apical segments. The Vs values for the LV segments around the infarcted area in the MSC group decreased significantly compared with the sham group (P < .05) 1 day after MSC transplantation, whereas they increased significantly 2 weeks after MSC transplantation compared with 1 day after LAD ligation (P < .05). CONCLUSIONS: This study demonstrates that quantitative tissue velocity imaging may provide a promising approach to quantitatively assessing LV regional systolic function before and after MSC transplantation.

Evaluation of abdominal aortic elasticity by strain rate imaging in patients with type 2 diabetes mellitus.

PURPOSE: To use strain rate imaging (SRI) to compare the abdominal aortic wall elasticity between patients with type 2 diabetes mellitus and controls. METHODS: We measured the abdominal aorta intima-media thickness (IMT) with B-mode echography, and the anterior and posterior wall displacement (d), strain, and strain rate (SR) with SRI, in 90 patients with type 2 diabetes mellitus and 30 control subjects (group A). The patients were classified into group B (normal IMT), group C (thickened IMT), and group D (one single atheroma plaque). RESULTS: d, strain, and SR were significantly lower in group B, C, and D than in group A (p < .05). Systolic, early-diastolic, and late-diastolic SR were lower in patients with diabetes (especially in group D) than in controls. There were significant differences in systolic SR, early-diastolic SR, and late-diastolic SR between group A and group B (p < .05). CONCLUSIONS: SRI is a noninvasive method that can demonstrate a loss in aorta wall elasticity in patients with diabetes with normal IMT.

Speckle reduction approach for breast ultrasound image and its application to breast cancer diagnosis.

OBJECTIVES: To retrospectively evaluate the effects of a speckle reduction algorithm on radiologists' diagnosis of malignant and benign breast lesions on ultrasound (US) images. METHODS: Using a database of 603 breast (US) images of 211 cases (109 benign lesions and 102 malignant ones), the original and speckle-reduced images were assessed by five radiologists and final assessment categories were assigned to indicate the probability of malignancy according to BI-RADS-US. The diagnostic sensitivity and specificity were investigated by the areas (Az) under the receiver operating characteristic (ROC) curves. RESULTS: The sensitivity and specificity of breast lesions on Ultrasound images improved from 88.7% to 94.3%, from 68.6% to 75.2%, respectively, and the area (Az) under ROC curve of diagnosis also increased from 0.843 to 0.939, Z=4.969, there were significant differences in the Az between the original breast lesions and speckle-reduced ones on Ultrasound images (P<0.001). The diagnostic accuracy of breast lesions had been highly improved from 78.67% to 92.73% after employing this algorithm. CONCLUSIONS: The results demonstrate the promising performance of the proposed speckle reduction algorithm in distinguishing malignant from benign breast lesions which will be useful for breast cancer diagnosis.

Tissue synchronization imaging of myocardial dyssynchronicity of the left ventricle in patients with coronary artery disease.

OBJECTIVE: The purpose of this study was to evaluate regional myocardial dyssynchronicity and velocity of the left ventricle in patients with coronary artery disease. METHODS: Tissue synchronization imaging analysis of the time to peak velocity (Tp) and peak velocity (Vp) of left ventricular longitudinal myocardial segments was performed for 60 patients with coronary artery disease and 40 healthy subjects. RESULTS: Tissue synchronization imaging revealed synchronous myocardia in the control group and disturbed myocardial synchrony in patients, with greater dyssynchrony than in the control group (P < .005). Compared with the control group, patients showed a higher Tp of the left ventricular anterior wall and interventricular septum (P < .001). The apex-to-base gradient of tissue velocity was absent in patients. The mean Vp of all segments except the apical segment of the interventricular septum in patients was decreased significantly (P < .05). CONCLUSIONS: Tissue synchronization imaging is a novel and noninvasive technique for quantitatively assessing regional myocardial Tp and Vp and can directly and quickly determine ischemia or infarction in myocardial segments.

Evaluation of cardiac global function using the myocardial performance index by tissue Doppler echocardiography in patients with uremia.

OBJECTIVE: The purpose of this study was to assess global ventricular function in patients with uremia by means of the myocardial performance index (MPI) derived from tissue Doppler echocardiography. METHODS: According to the left ventricular mass index and pericardial effusion, 45 patients with uremia were classified into 2 groups: a uremia group and a uremia with pericardial effusion group. To calculate left ventricular MPI (LVMPI) and right ventricular MPI (RVMPI) by tissue Doppler echocardiography, the isovolumic contraction time (ICT), isovolumic relaxation time (IRT), and ejection time (ET) were measured at different sites in the mitral and tricuspid annuli. RESULTS: The mean ICT and IRT were longer, the ET was shorter, and the LVMPI and RVMPI were higher in the 2 disease groups than in a control group, and the indices were higher in the uremia with pericardial effusion group than in the uremia group. The increase of the LVMPI was more obvious than that of the RVMPI. There was a significant difference in the mean LVMPI and RVMPI among the 3 groups (P<.01). The MPI was positively correlated with the IRT and the sum of the ICT and IRT and negatively correlated with the ET. CONCLUSIONS: Both left and right ventricular systolic and diastolic function are impaired in patients with uremia. The MPI could be measured by tissue Doppler echocardiography, and we suggest that this index provides a novel, noninvasive method for clinical research on global myocardial performance in patients with uremia.

Breast ultrasound image enhancement using fuzzy logic.

Breast cancer is still a serious disease in the world. Early detection is very essential for breast cancer prevention and diagnosis. Breast ultrasound (US) imaging has been proven to be a valuable adjunct to mammography in the detection and classification of breast lesions. Because of the fuzzy and noisy nature of the US images and the low contrast between the breast cancer and tissue, it is difficult to provide an accurate and effective diagnosis. This paper presents a novel algorithm based on fuzzy logic that uses both the global and local information and has the ability to enhance the fine details of the US images while avoiding noise amplification and overenhancement. We normalize the images and then fuzzify the normalized images based on the maximum entropy principle. Edge and textural information are extracted to describe the lesion features and the scattering phenomenon of US images and the contrast ratio measuring the degree of enhancement is computed and modified. The defuzzification process is used to obtain the enhanced US images. To demonstrate the performance of the proposed approach, the algorithm was tested on 86 breast US images. Experimental results confirm that the proposed method can effectively enhance the details of the breast lesions without overenhancement or underenhancement.