Biventricular intraventricular mechanical and electrical dyssynchrony in pulmonary arterial hypertension.

Background: Pulmonary arterial hypertension (PAH) leads to myocardial remodeling, manifesting as mechanical dyssynchrony (M-dys) and electrical dyssynchrony (E-dys), in both right (RV) and left ventricles (LV). However, the impacts of layer-specific intraventricular M-dys on biventricular functions and its association with E-dys in PAH remain unclear. Methods: Seventy-nine newly diagnosed patients with PAH undergoing cardiac magnetic resonance scanning were consecutively recruited between January 2011 and December 2017. The biventricular volumetric and layer-specific intraventricular M-dys were analyzed. The QRS duration z-scores were calculated after adjusting for age and sex. Results: 77.22 % of patients were female (mean age 30.30 ± 9.79 years; median follow-up 5.53 years). Further, 29 (36.71 %) patients succumbed to all-cause mortality by the end of the study. At the baseline, LV layer-specific intraventricular M-dys had apparent transmural gradients compared with RV in the radial and circumferential directions. However, deceased patients lost the transmural gradients. The LV longitudinal strain rate time to late diastolic peak in the myocardial region (LVmyoLSRTTLDPintra) predicted long-term survival. The Kaplan-Meier curve revealed that patients with PAH with LVmyoLSRTTLDPintra <20.01 milliseconds had a worse prognosis. Larger right ventricle (RV) intraventricular M-dys resulted in worse RV ejection fraction. However, larger LV intraventricular M-dys in the late diastolic phase indicated remarkable exercise capacity and higher LV stroke volume index. E-dys and intraventricular M-dys had no direct correlations. Conclusions: The layer-specific intraventricular M-dys had varying impacts on biventricular functions in PAH. PAH patients with LVmyoLSRTTLDPintra <20.01 milliseconds had a worse prognosis. LV intraventricular M-dys in the late diastolic phase needs more attention to precisely evaluate LV function.

Large B-cell Lymphoma with IRF4 Rearrangement in the Nasolacrimal Duct: A Clinicopathological Study of One Case and Literature Review.

BACKGROUND: Large B-cell lymphoma (LBCL) with interferon regulatory factor 4 (IRF4) rearrangement (LBCL-IRF4) is a rare subtype of LBCL, with a high prevalence in Waldeyer's ring as well as the neck, head and gastrointestinal lymph nodes. MATERIALS AND METHODS: A patient with 2-month clinical symptoms of nasal obstruction and facial swelling was reported in this short review. A nasal endoscopy examination revealed a neoplasm in the inferior nasal meatus. Both CT and enhanced MRI showed that a soft tissue occupied the nasolacrimal duct, with bone destruction, and extended into the left nasal cavity and left lacrimal gland area. Then, a biopsy of the neoplasm in the inferior nasal meatus was performed. RESULTS: HE staining results showed that neoplastic cells presented diffuse growth patterns, abundant cytoplasm, vacuole shape, lightly stained nuclei, and irregular nuclear membrane. Immunohistochemistry staining results revealed MUM1(+), Bcl6(+), CD20(+), CD79α(+), and CD10(+). FISH analyses detected positive IRF4 rearrangement. LBCL-IRF4 was diagnosed in the patient. The patient received treatment with four cycles of R-CHOP and two times of rituximab, followed up for 2 years, and finally got complete remission. CONCLUSION: For the first time, we summarize the imaging and pathological features, drug treatment, and curative effect of LBCL-IRF4 in the nasolacrimal duct.

Imaging characteristics and prognostic factors of Behcet's disease with arterial involvement: A long-term follow-up study.

PURPOSE: To investigate the imaging characteristics and prognostic factors for the long-term survival of Behcet's disease (BD) with arterial involvement. METHODS: In this retrospective study, BD patients with arterial involvement were identified from January 2003 to January 2020. Arterial lesions were detected by ultrasonography, traditional arteriography, and/or computed tomography angiography (CTA). Cox proportional hazards regression analyses were performed to identify the prognostic factors. RESULTS: Totally, 84 BD patients with arterial involvement were identified (73.8 % males). The mean age at BD diagnosis was 39.1 ± 13.1 years. Arterial involvement was the initial manifestation in 33.3 % of the patients, and the median time from BD diagnosis to arterial involvement was 6 (IQR 1-15.5) years for the rest of patients. Systemic artery involvement and pulmonary artery involvement (PAI) were found in 64 and 27 patients, respectively. Approximately 94.0 % (79/84) of the patients had more than one artery involved concurrently or successively during the course of BD. Aneurysm/dilation was the most prevalent lesion in the aorta (76.0 %), while stenosis/occlusion was the main lesion of the coronary artery (90.9 %) and other aortic branches (74.5 %). Pulmonary hypertension was found in 70.4 % (19/27) of patients with PAI. The 5- and 10-year survival rates of BD patients with arterial involvement were 87.4 % and 84.1 %, respectively. Cardiac involvement (HR: 4.34) and pulmonary artery aneurysm/dilation (HR: 4.89) were independently associated with mortality. CONCLUSIONS: Arterial lesions associated with BD usually involve multiple arteries and manifest differently in different types of arteries. Cardiac involvement and pulmonary artery aneurysm/dilation are independent prognostic factors of BD patients with arterial involvement.

Right heart thrombus in acute pulmonary embolism: A single center experience in China.

Right heart thrombus (RHT) is a rare but life-threatening condition in acute pulmonary embolism (APE) without clear management guidelines. This study aimed to address the clinical characteristics and outcomes of RHT-APE in Chinese patients. In this study, 17 RHT-APE and 329 non-RHT-APE patients, who were diagnosed between September 2015 and August 2019, were retrospectively recruited with the median follow-up was 360 days. The overall prevalence of RHT was 4.91% in APE. Its prevalence increased along the increase of APE risk stratifications. Comparisons showed that with higher proportion of male gender and younger age, RHT-APE patients also had worse hemodynamic instability and heart function, and higher risk stratification levels than non-RHT-APE patients. After adjusting by age and gender, multivariate logistic regression analysis found high/intermediate-high risk stratification, decreased right ventricular (RV) motion, NT-proBNP >600 pg/mL, and RV dysfunction were risk factors for RHT. Kaplan-Meier analysis showed non-RHT had better prognosis than RHT patients (30-day survival: log-rank: p < 0.001; 90-day survival: log-rank: p = 0.002). The multivariate logistic regression analysis showed RHT was an independent risk factor for 30-day mortality in APE. The subgroup analysis showed RHT would result in worse outcomes in patients who already had higher APE early mortality risk. RHT would increase the risk of 30- and 90-day mortality in APE. More attention should be paid to young male APE patients with decreased RV motion, NT-proBNP >600 pg/mL, RV dysfunction, or high level of risk stratification, to exclude the coexistence of RHT.

Long-read genome assemblies reveal a cis-regulatory landscape associated with phenotypic divergence in two sister Siniperca fish species.

Due to the difficulty in accurately identifying structural variants (SVs) across genomes, their impact on cis-regulatory divergence of closely related species, especially fish, remains to be explored. Recently identified broad H3K4me3 domains are essential for the regulation of genes involved in several biological processes. However, the role of broad H3K4me3 domains in phenotypic divergence remains poorly understood. Siniperca chuatsi and S. scherzeri are closely related but divergent in several phenotypic traits, making them an ideal model to study cis-regulatory evolution in sister species. Here, we generated chromosome-level genomes of S. chuatsi and S. scherzeri, with assembled genome sizes of 716.35 and 740.54 Mb, respectively. The evolutionary histories of S. chuatsi and S. scherzeri were studied by inferring dynamic changes in ancestral population sizes. To explore the genetic basis of adaptation in S. chuatsi and S. scherzeri, we performed gene family expansion and contraction analysis and identified positively selected genes (PSGs). To investigate the role of SVs in cis-regulatory divergence of closely related fish species, we identified high-quality SVs as well as divergent H3K27ac and H3K4me3 domains in the genomes of S. chuatsi and S. scherzeri. Integrated analysis revealed that cis-regulatory divergence caused by SVs played an essential role in phenotypic divergence between S. chuatsi and S. scherzeri. Additionally, divergent broad H3K4me3 domains were mostly associated with cancer-related genes in S. chuatsi and S. scherzeri and contributed to their phenotypic divergence.

Improvements in Brazed-Joint Properties of Silicon Nitride and Titanium Alloys Using Laser-Induced Microscale Rice Leaf Structures.

Si3N4 ceramics with a microscale rice leaf structure (MRLS) and titanium alloy were connected via brazing, and the influence of the surface microstructure on the ceramic connection was analyzed. MRLS fabrication is an efficient and high-degree-of-freedom method that can be used to change a material's surface morphology and wettability. The MRLS was obtained at a laser power of 110 W, with line spacings of 100 and 50 µm. The laser-treated surface included nanoparticles and micro particles, exhibiting a coral-like structure after agglomeration. When the MRLS was used to braze the titanium alloy, no defects were observed at the brazing interface, and the formation was excellent. Throughout the brazed joint, the MRLS remained intact and formed a strong metallurgical bond with the brazing filler metal. A finite element analysis was performed to study the cross-sectional morphology after joint fracture; from the load-time curve, it was found that the MRLS on the surface not only helped improve the mechanical occlusion and brazing area at the interface, but also helped generate compressive stress on the Si3N4 side. Crack propagation was hindered, thereby increasing the joint strength.

Fabrication of Metallic Superhydrophobic Surfaces with Tunable Condensate Self-Removal Capability and Excellent Anti-Frosting Performance.

Laser fabrication of metallic superhydrophobic surfaces (SHSs) for anti-frosting has recently attracted considerable attention. Effective anti-frosting SHSs require the efficient removal of condensed microdroplets through self-propelled droplet jumping, which is strongly influenced by the surface morphology. However, detailed analyses of the condensate self-removal capability of laser-structured surfaces are limited, and guidelines for laser processing parameter control for fabricating rationally structured SHSs for anti-frosting have not yet been established. Herein, a series of nanostructured copper-zinc alloy SHSs are facilely constructed through ultrafast laser processing. The surface morphology can be properly tuned by adjusting the laser processing parameters. The relationship between the surface morphologies and condensate self-removal capability is investigated, and a guideline for laser processing parameterization for fabricating optimal anti-frosting SHSs is established. After 120 min of the frosting test, the optimized surface exhibits less than 70% frost coverage because the remarkably enhanced condensate self-removal capability reduces the water accumulation amount and frost propagation speed (<1 µm/s). Additionally, the material adaptability of the proposed technique is validated by extending this methodology to other metals and metal alloys. This study provides valuable and instructive insights into the design and optimization of metallic anti-frosting SHSs by ultrafast laser processing.

A generalizable and tunable engineered ecosystem provides a clear route to prosperity and well-being to harness the world's aquatic "blue" food systems to help end hunger: A perspective.

Seafood security is essential in modern society. In 2013, Bush and colleagues stated, 'Aquaculture, farming aquatic organisms, provides close to 50% of the world's supply of seafood, with a value of United States $125 billion. It makes up 13% of the world's animal-source protein (excluding eggs and dairy) and employs an estimated 24 million people'. With the increase in the human population and reducing fishing resources, humans increasingly rely on aquacultural products as the primary protein sources for many countries. Aquacultural productivity has been improving in recent years, and in certain countries, the aquaculture output is more than the fishing output. For example, Chinese aquaculture production is more than fishing output, which provides one-third of animal protein. Thus, intensive aquaculture has become the main supply with global aquatic products (FAO). In recent years, it is estimated that each person consumption of aquaculture products is 130 kg in some countries (Iceland). Here, we illustrate the road blocker in farmed shrimp production and provide our resolution. The global pandemic of white spot syndrome (WSS), caused by the white spot syndrome virus (WSSV), bears a devastating economic loss in farmed shrimp production, thereby jeopardizing seafood security. Currently, there is no effective control for WSS. Conventional single-species intensive farming removes the spatiotemporal interaction between different species. We hypothesize that establishing the spatiotemporal interface of a predator-prey may control WSS outbreak. We search for the pathways for the mechanisms by which predator-prey species interact and compete across spatial scales to characterize WSSV dispersal at regional scales for the local spatiotemporal structure of viral transmission. Thus, we create a generalizable and tunable engineered ecosystem that provides a clear route to prosperity and well-being to harness the world's aquatic "blue" food systems to help end hunger.

Transgelin exacerbates pulmonary artery smooth muscle cell dysfunction in shunt-related pulmonary arterial hypertension.

AIMS: Orchestrating the transition from reversible medial hypertrophy to irreversible plexiform lesions is crucial for pulmonary arterial hypertension related to congenital heart disease (CHD-PAH). Transgelin is an actin-binding protein that modulates pulmonary arterial smooth muscle cell (PASMC) dysfunction. In this study, we aimed to probe the molecular mechanism and biological function of transgelin in the pathogenesis of CHD-PAH. METHODS AND RESULTS: Transgelin expression was detected in lung tissues from both CHD-PAH patients and monocrotaline (MCT)-plus aortocaval (AV)-induced PAH rats by immunohistochemistry. In vitro, the effects of transgelin on the proliferation, migration, and apoptosis of human PASMCs (HPASMCs) were evaluated by the cell count and EdU assays, transwell migration assay, and TUNEL assay, respectively. And the effect of transgelin on the expression of HPASMC phenotype markers was assessed by the immunoblotting assay. (i) Compared with the normal control group (n = 12), transgelin expression was significantly overexpressed in the pulmonary arterioles of the reversible (n = 15) and irreversible CHD-PAH group (n = 4) (reversible group vs. control group: 18.2 ± 5.1 vs. 13.6 ± 2.6%, P < 0.05; irreversible group vs. control group: 29.9 ± 4.7 vs. 13.6 ± 2.6%, P < 0.001; irreversible group vs. reversible group: 29.9 ± 4.7 vs. 18.2 ± 5.1, P < 0.001). This result was further confirmed in MCT-AV-induced PAH rats. Besides, the transgelin expression level was positively correlated with the pathological grading of pulmonary arteries in CHD-PAH patients (r = 0.48, P = 0.03, n = 19). (ii) Compared with the normal control group (n = 12), TGF-ß1 expression was notably overexpressed in the pulmonary arterioles of the reversible (n = 15) and irreversible CHD-PAH group (n = 4) (reversible group vs. control group: 14.8 ± 4.4 vs. 6.0 ± 2.5%, P < 0.001; irreversible group vs. control group: 20.1 ± 4.4 vs. 6.0 ± 2.5%, P < 0.001; irreversible group vs. reversible group: 20.1 ± 4.4 vs. 14.8 ± 4.4, P < 0.01). The progression-dependent correlation between TGF-ß1 and transgelin was demonstrated in CHD-PAH patients (r = 0.48, P = 0.04, n = 19) and MCT-AV-induced PAH rats, which was further confirmed at sub-cellular levels. (iii) Knockdown of transgelin diminished proliferation, migration, apoptosis resistance, and phenotypic transformation of HPASMCs through repressing the TGF-ß1 signalling pathway. On the contrary, transgelin overexpression resulted in the opposite effects. CONCLUSIONS: These results indicate that transgelin may be an indicator of CHD-PAH development via boosting HPASMC dysfunction through positive regulation of the TGF-ß1 signalling pathway, as well as a potential therapeutic target for the treatment of CHD-PAH.

Hypoxia triggers the outbreak of infectious spleen and kidney necrosis virus disease through viral hypoxia response elements.

Hypoxia frequently occurs in aquatic environments, especially in aquaculture areas. However, research on the relationship between hypoxic aquatic environments with viral diseases outbreak is limited, and its underlying mechanisms remain elusive. Herein, we demonstrated that hypoxia directly triggers the outbreak of infectious spleen and kidney necrosis virus (ISKNV) disease. Hypoxia or activated hypoxia-inducible factor (HIF) pathway could remarkably increase the levels of viral genomic DNA, titers, and gene expression, indicating that ISKNV can response to hypoxia and HIF pathway. To reveal the mechanism of ISKNV respond to HIF pathway, we identified the viral hypoxia response elements (HREs) in ISKNV genome. Fifteen viral HREs were identified, and four related viral genes responded to the HIF pathway, in which the hre-orf077r promoter remarkably responded to the HIF pathway. The level of orf077r mRNA dramatically increased after the infected cells were treated with dimethyloxalylglycine (DMOG) or the infected cells/fish subjected to hypoxic conditions, and overexpressed orf077r could remarkably increase the ISKNV replication. These finding shows that hypoxic aquatic environments induce the expression of viral genes through the viral HREs to promote ISKNV replication, indicating that viral HREs might be important biomarkers for the evaluation of the sensitivity of aquatic animal viral response to hypoxia stress. Furthermore, the frequencies of viral HREs in 43 species aquatic viral genomes from 16 families were predicted and the results indicate that some aquatic animal viruses, such as Picornavirdea, Dicistronviridae, and Herpesviridae, may have a high risk to outbreak when the aquatic environment encounters hypoxic stress.

The Interaction of Mandarin Fish DDX41 with STING Evokes type I Interferon Responses Inhibiting Ranavirus Replication.

DDX41 is an intracellular DNA sensor that evokes type I interferon (IFN-I) production via the adaptor stimulator of interferon gene (STING), triggering innate immune responses against viral infection. However, the regulatory mechanism of the DDX41-STING pathway in teleost fish remains unclear. The mandarin fish (Siniperca chuatsi) is a cultured freshwater fish species that is popular in China because of its high market value. With the development of a high-density cultural mode in mandarin fish, viral diseases have increased and seriously restricted the development of aquaculture, such as ranavirus and rhabdovirus. Herein, the role of mandarin fish DDX41 (scDDX41) and its DEAD and HELIC domains in the antiviral innate immune response were investigated. The level of scDDX41 expression was up-regulated following treatment with poly(dA:dT) or Mandarin fish ranavirus (MRV), suggesting that scDDX41 might be involved in fish innate immunity. The overexpression of scDDX41 significantly increased the expression levels of IFN-I, ISGs, and pro-inflammatory cytokine genes. Co-immunoprecipitation and pull-down assays showed that the DEAD domain of scDDX41 recognized the IFN stimulatory DNA and interacted with STING to activate IFN-I signaling pathway. Interestingly, the HELIC domain of scDDX41 could directly interact with the N-terminal of STING to induce the expression levels of IFN-I and ISGs genes. Furthermore, the scDDX41 could enhance the scSTING-induced IFN-I immune response and significantly inhibit MRV replication. Our work would be beneficial to understand the roles of teleost fish DDX41 in the antiviral innate immune response.

Evidence for a Novel Antiviral Mechanism of Teleost Fish: Serum-Derived Exosomes Inhibit Virus Replication through Incorporating Mx1 Protein.

Exosomes are associated with cancer progression, pregnancy, cardiovascular diseases, central nervous system-related diseases, immune responses and viral pathogenicity. However, study on the role of exosomes in the immune response of teleost fish, especially antiviral immunity, is limited. Herein, serum-derived exosomes from mandarin fish were used to investigate the antiviral effect on the exosomes of teleost fish. Exosomes isolated from mandarin fish serum by ultra-centrifugation were internalized by mandarin fish fry cells and were able to inhibit Infectious spleen and kidney necrosis virus (ISKNV) infection. To further investigate the underlying mechanisms of exosomes in inhibiting ISKNV infection, the protein composition of serum-derived exosomes was analyzed by mass spectrometry. It was found that myxovirus resistance 1 (Mx1) was incorporated by exosomes. Furthermore, the mandarin fish Mx1 protein was proven to be transferred into the recipient cells though exosomes. Our results showed that the serum-derived exosomes from mandarin fish could inhibit ISKNV replication, which suggested an underlying mechanism of the exosome antivirus in that it incorporates Mx1 protein and delivery into recipient cells. This study provided evidence for the important antiviral role of exosomes in the immune system of teleost fish.

Litopenaeus vannamei Sma and Mad related protein 5 gene is involved in stress response and white spot syndrome virus infection.

Cell survival is based on the stability of intracellular state. It was well known that biochemical reactions in cells require specific intracellular environments, such as pH and calcium concentration. While the mechanism of stabilizing the intracellular environment is complex and far from clear. In this study, a Sma and Mad related protein 5 gene (LvSmad5) of Litopenaeus vannamei was cloned. LvSmad5 was located to both cytoplasm and nucleus. And subcellular localization of LvSmad5 was responsed to the changing of cells internal and external environment. Besides, it was found that subcellular localization of LvSmad5 was also regulated by unfolded protein response. Moreover, it was proved that nucleic localization of LvSmad5 could significantly increase the white spot syndrome virus (WSSV) infection in shrimp, and knockdown expression of LvSmad5 decreased the cumulative mortality of WSSV infection shrimp. Further investigation revealed that cytoplasm LvSmad5 could interplay with shrimp hexokinase 1, and contribute to glycolysis. These results indicated that LvSmad5 played a role in L. vannamei environmental stress response, and was used by WSSV for its replication.

CYLD mediates human pulmonary artery smooth muscle cell dysfunction in congenital heart disease-associated pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a common complication of congenital heart disease (CHD). Deubiquitinase cylindromatosis (CYLD) has been reported to significantly aggravate vascular smooth muscle cell (VSMC) phenotypic transformation, proliferation, and migration. Here, we aimed to further investigate its roles and underlying mechanisms in the CHD-PAH development. The expression of CYLD in the lung tissues from CHD-PAH patients and monocrotaline (MCT) plus aortocaval (AV)-induced PAH rats, pulmonary artery smooth muscle cells (PASMCs) from MCT-AV-induced PAH rats, and human PASMCs (HPASMCs) was evaluated. After infection with CYLD siRNA or pcNDA3.1-CYLD, the proliferation, migration, and apoptosis of HPASMCs were measured using an EdU assay, transwell and scratch wound healing assays, and flow cytometric assay, respectively. An adeno-associated virus (AAV) vector encoding CYLD was used to suppress CYLD expression by being intratracheally instilled in rats 7 days before MCT-AV treatment. The results showed that CYLD was increased in the lung tissues from CHD-PAH patients and MCT-AV-induced PAH rats, and in PASMCs from MCT-AV-induced PAH rats. The contractile-type HPASMCs expressed low levels of CYLD, while the proliferative synthetic-type HPASMCs expressed high levels of CYLD. In addition, CYLD could mediate HPASMC dysfunction, which regulated HPASMC phenotypic transformation and proliferation via the modulation of p38 and ERK activation, while CYLD regulated HPASMC migration via the modulation of p38 activation. In vivo results demonstrated that the local suppression of CYLD expression could attenuate the increased levels of PAH and its associated pulmonary vascular remodeling in MCT-AV-induced PAH rats. Collectively, these results indicated that CYLD might be a potential novel therapeutic target for the prevention of PAH and pulmonary vascular remodeling in CHD-PAH through the modulation of HPASMC dysfunction.

Balloon pulmonary angioplasty reverse right ventricular remodelling and dysfunction in patients with inoperable chronic thromboembolic pulmonary hypertension: a systematic review and meta-analysis.

OBJECTIVES: Right ventricular (RV) function is considered the major determinant of prognosis in patients with chronic thromboembolic pulmonary hypertension (CTEPH). The aim of this meta-analysis was to evaluate RV remodelling and function following balloon pulmonary angioplasty (BPA) in patients with inoperable CTEPH or persistent/recurrent pulmonary hypertension (PH) after pulmonary endarterectomy (PEA). METHODS: We reviewed all studies evaluating RV function by cardiac magnetic resonance (CMR) and/or echocardiography pre- and post-BPA from PubMed/Medline prior to 15 December 2019. Ten (299 patients) of the 29 studies retrieved met the inclusion criteria: 5 CMR and 5 echocardiography studies. The systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines. RESULTS: Pooled data from CMR studies revealed BPA resulted in a significantly decreased RV end-diastolic volume index (weighted mean difference (WMD) - 28.33 ml/m2, p < 0.00001) and RV end-systolic volume index (WMD - 29.06 ml/m2, p < 0.00001) accompanied by an increased RV ejection fraction (RVEF, WMD 8.97%, p < 0.00001). Data from the echocardiography studies showed BPA resulted in decreased RV basal diameter (WMD - 0.37 cm, p = 0.0009) and an increase of RV fractional area change (WMD 5.97 %, p = 0.003), but improvements of tricuspid annular plane systolic excursion (TAPSE) and S' were not significant. CONCLUSIONS: BPA improves RVEF and decreases RV volumes in patients with inoperable CTEPH or persistent/recurrent PH after PEA. KEY POINTS: • Balloon pulmonary angioplasty improves RVEF and decreases RV volumes in patients with inoperable CTEPH or persistent/recurrent PH after PEA.

Development of a novel quantitative function between spectral value and metmyoglobin content in Tan mutton.

This study was aimed to establish a quantitative function between spectral reflectance values and metmyoglobin (MetMb) content in Tan mutton during refrigeration. Near-infrared hyperspectral data combined with generalized two-dimensional correlation spectroscopy (G2D-COS) method to identify characteristic bands and investigate the sequence of chemical waveband changes. Characteristic wavebands identified by G2D-COS analysis had the best performance in predicting the content of MetMb, with a high R2p of 0.849, a low RMSEP of 2.695 and a high RPD of 2.786. The results showed that the G2D-COS may be a powerful tool for describing intensity changes of MetMb band. The partial least square regression method was used to develop the relationships between the spectral values and MetMb content in Tan mutton meat for predicting MetMb content. This study has provided a convenient and rapid non-destructive quantitative method for assessing the color of Tan mutton meat.

Roles of extracellular matrix components in Tiger frog virus attachment to fathead minnow (Pimephales promelas) cells.

Tiger frog virus (TFV) belongs to the genus Ranavirus (family Iridoviridae) and causes significant harm in cultured frogs, resulting in substantial losses in ecological and economic field in Southern China. Attachment is the first step in viral life cycle, which is dependent on the interactions of virions with extracellular matrix (ECM) components. Studying this process will help in understanding virus infection and controlling viral diseases. In this study, the roles of primary ECM components in TFV attachment were investigated. The results on the kinetics of virus attachment showed TFV successful attachment to the cell surface as a relatively rapid process after TFV was used to inoculate cells for 10 min at 4 °C. Western blot and quantitative PCR analyses results showed that soluble fibronectin, collagen IV, laminin, or hyaluronic acid treatment with TFV caused no significant effect on virus attachment. Soluble heparin, heparan sulfate and chondroitin sulfate A/B could inhibit TFV attachment in a dose-dependent manner. Enzymic digestion by cell surface heparin/heparan sulfate using heparinase I, II, and III could significantly prevent TFV attachment, suggesting that heparan sulfate plays an important role in TFV attachment. Furthermore, the binding assays of heparin-agarose beads and virion showed that TFV virions specifically bound with heparin in a dose-dependent manner. Given that heparin is a structural analogue of heparan sulfate, the above results suggest that heparan sulfate might serve as an attachment factor of TFV infection. Our work would be beneficial to understand the mechanisms of TFV attachment and the interactions of TFV with cellular receptor(s).

Nestin represents a potential marker of pulmonary vascular remodeling in pulmonary arterial hypertension associated with congenital heart disease.

OBJECTIVE: Reportedly, nestin was re-expressed in proliferative synthetic-type pulmonary artery smooth muscle cells (PASMCs) and obligatory for PASMC proliferation in pulmonary arterial hypertension (PAH). Accordingly, nestin is increased in pulmonary vascular lesions of congenital heart disease (CHD)-associated PAH patients. We tested the hypothesis whether nestin was re-expressed in proliferative synthetic-type PASMCs and associated with pulmonary vascular remodeling in CHD-PAH. MATERIALS AND METHODS: Nestin expression was tested using lung tissues from CHD-PAH patients and monocrotaline (MCT) plus aortocaval (AV) shunt-induced PAH rats, human PASMCs (HPASMCs), and pulmonary artery endothelial cells (PAECs) and PASMCs from MCT-AV-induced PAH rats. The role and possible mechanism of nestin on HPASMC proliferation, apoptosis, cell cycle and migration were investigated by assays of CCK-8, EdU, TUNEL, flow cytometry, transwell chamber and immunoblotting assays. RESULTS: Nestin was solely expressed in proliferative synthetic-type PASMCs, but rarely detected in PAECs. Nestin was barely detected in normal pulmonary arterioles and occlusive pulmonary vascular lesions. Its expression was robustly increased in developing pulmonary vasculature, but returned to normal levels at the late stage of pulmonary vascular remodeling in lung tissues from CHD-PAH patients and MCT-AV-induced PAH rats. Besides, nestin peaks were consistent with the histological features in lung tissues of MCT-AV-induced PAH rats. Moreover, nestin overexpression effectively promoted HPASMC phenotypic transformation, proliferation, apoptosis resistance and migration via enhancing Wnt/ß-catenin activation. CONCLUSIONS: These data indicated that nestin was re-expressed in proliferative synthetic-type PASMCs and might represent a potential marker of pulmonary vascular remodeling in CHD-PAH.

Two-dimensional speckle tracking echocardiography detected interventricular dyssynchrony predicts exercise capacity and disease severity in pre-capillary pulmonary hypertension.

BACKGROUND: Right ventricular (RV) intraventricular mechanical dyssynchrony detected by two-dimensional speckle tracking echocardiography (2D-STE) has been reported to be correlated with a decrease in RV contractile efficiency in pulmonary hypertension (PH) patients, while little attention has been paid to biventricular dysfunction. Therefore, we aimed to evaluate the predictive value of 2D-STE detected interventricular dyssynchrony for exercise capacity and disease severity in patients with pre-capillary PH (PcPH). METHODS: Conventional transthoracic echocardiography, 2D-STE and cardiopulmonary exercise tests (CPETs) were performed in all participants. Intra- and interventricular dyssynchrony were calculated as the standard deviation (SD) of the time intervals corrected for heart rate between QRS onset and peak longitudinal strain. Multivariate linear regression analyses were performed to identify independent predictors of peak oxygen consumption (PVO2) during the CPET. Multivariable logistical regression modeling was used to analyze the associations between interventricular dyssynchrony and risk assessment. RESULTS: Sixty-six PcPH patients were consecutively recruited (19 male and 47 female, average 35 years old). WHO functional class, N-terminal pro-brain natriuretic peptide (BNP) and body mass index were included as independent predictors in the first multivariate regression analysis of clinical data without echocardiographic parameters (Model-1, r2=0.423, P<0.001). We subsequently added conventional echocardiographic parameters and 2D-STE parameters to the clinical data, RV fractional area change (Model-2, r2=0.417, P<0.001), RV global longitudinal strain (Model-3, r2=0.454, P=0.001), RV intraventricular dyssynchrony (Model-4: r2=0.474, P<0.001) and interventricular dyssynchrony (Model-5, r2=0.483, P<0.001) were identified as independent predictors of PVO2. Interventricular dyssynchrony, calculated as the SD of the time intervals of nine segments, was independently associated with risk assessment (odd ratio 1.027, 95% CI: 1.003-1.052, P=0.03). The area under the receiver-operating characteristic curve (AUC) was 0.73 (P<0.001). CONCLUSIONS: Interventricular dyssynchrony detected by 2D-STE contributed to a better evaluation of exercise capacity and disease severity in PcPH patients.

A child with household transmitted COVID-19.

BACKGROUND: Although people of all ages are susceptible to the novel coronavirus infection, which is presently named "Coronavirus Disease 2019" (COVID-19), there has been relatively few cases reported among children. Therefore, it is necessary to understand the clinical characteristics of COVID-19 in children and the differences from adults. CASE PRESENTATION: We report one pediatric case of COVID-19. A 14-month-old boy was admitted to the hospital with a symptom of fever, and was diagnosed with a mild form of COVID-19. The child's mother and grandmother also tested positive for SARS-CoV-2 RNA. However, the lymphocyte counts were normal. The chest computed tomography (CT) revealed scattered ground glass opacities in the right lower lobe close to the pleura and resorption after the treatment. The patient continued to test positive for SARS-CoV-2 RNA in the nasopharyngeal swabs and stool at 17 days after the disappearance of symptoms. CONCLUSION: The present pediatric case of COVID-19 was acquired through household transmission, and the symptoms were mild. Lymphocyte counts did not significantly decrease. The RNA of SARS-CoV-2 in stool and nasopharyngeal swabs remained positive for an extended period of time after the disappearance of symptoms. This suggests that attention should be given to the potential contagiousness of pediatric COVID-19 cases after clinical recovery.