Genetic and Pathogenic Characterization of a New Iridovirus Isolated from Cage-Cultured Large Yellow Croaker (Larimichthys crocea) in China

Iridoviruses are an important pathogen of ectothermic vertebrates and are considered a significant threat to aquacultural fish production. Recently, one of the most economically important marine species in China, the large yellow croaker (Larimichthys crocea), has been increasingly reported to be the victim of iridovirus disease. In this study, we isolated and identified a novel iridovirus, LYCIV-ZS-2020, from cage-cultured large yellow croaker farms in Zhoushan island, China. Genome sequencing and subsequent phylogenetic analyses showed that LYCIV-ZS-2020 belongs to the genus Megalocytivirus and is closely related to the Pompano iridoviruses isolated in the Dominican Republic. LYCIV-ZS-2020 enriched from selected tissues of naturally infected large yellow croaker was used in an artificial infection trial and the results proved its pathogenicity in large yellow croaker. This is the first systematic research on the genetic and pathogenic characterization of iridovirus in large yellow croakers, which expanded our knowledge of the iridovirus.

Age and Sex Differences in the Association of Sleep Duration and Overweight/Obesity among Chinese Participants Age above 45 Years: A Cohort Study

OBJECTIVES

We aimed to evaluate the association between sleep duration and obesity and estimate the attributable risk of sleep in the China Health and Retirement Longitudinal Study surveys (CHARLS).

METHODS

A total of 9061 adults aged 45 years above from CHARLS (2011-2015) were included. The main outcome of this study was incident overweight/obesity specific to general and abdominal obesity. Overweight/obesity was defined as BMI ≥ 23.0 (kg/m2) and BMI≥27.5 (kg/m2), respectively. Abdominal obesity was defined as waist circumference ≥90 cm for men and ≥80 cm for women. Self-reported sleep durations were obtained using a structured questionnaire. We assessed hazard ratios (HRs) and 95% confidence intervals (CIs) as well as the population attributable fraction (PAF) for associations between sleep duration and obesity.

RESULTS

986 and 606 participants were identified as overweight and general obesity respectively, 1253 experienced abdominal obesity events. In multivariable-adjusted models, participants with daytime sleep of 0-30 minutes and more than 30 minutes associated with 30% (HR: 0.70, 95% CI: 0.56-0.87) and 35% (HR: 0.65, 95% CI: 0.55-0.78) decreased incident overweight risk respectively compared to those having no daytime sleep, this association also found among females and middle-aged, not males or elderly. Similarly, 0-30 minutes (HR: 0.68, 95% CI: 0.48-0.96) and more than 30 minutes of daytime sleep (HR: 0.73, 95% CI: 0.59-0.91) were associated with a reduced risk of abdominal obesity, similar results also found among females and middle-aged. Compared with 7-9 hours of nocturnal sleep, people who slept 5-7 hours had a reduced risk of overweight (HR: 0.59, 95% CI=0.47-0.74),but not found in subgroups. The hazard role of long nocturnal sleep for abdominal obesity was only found among elderly (HR: 2.33, 95% CI=1.35-4.04) and males (HR: 2.24, 95% CI=1.17-4.29). Compared with moderate total sleepers (7-9hours/day), participants with short total sleep duration exhibited an elevated risk of overweight (HR: 1.13, 95% CI=1.00-1.28), this also found among middle-aged. The PAF for inadequate total sleep duration (<7 hours/day) was 10.77% for overweight individuals.

CONCLUSIONS

Insufficient sleep duration was associated with an elevated risk of overweight only detected among middle-aged not elderly and other subgroups specific by age. The risks for abdominal obesity were increased for males and middle-aged with long nocturnal sleep. Daytime sleep may significantly reduce the risk of overweight and abdominal obesity in female and middle-aged individuals. The link between sleep duration and obesity requires further study.

Mesoporous polydopamine nanoparticles carrying peptide RL-QN15 show potential for skin wound therapy

BACKGROUND

Skin wound healing remains a considerable clinical challenge, thus stressing the urgent need for the development of new interventions to promote repair. Recent researches indicate that both peptides and nanoparticles may be potential therapies for the treatment of skin wounds.

METHODS

In the current study, the mesoporous polydopamine (MPDA) nanoparticles were prepared and the peptide RL-QN15 that was previously identified from amphibian skin secretions and exhibited significant potential as a novel prohealing agent was successfully loaded onto the MPDA nanoparticles, which was confirmed by results of analysis of scanning electron microscopy and fourier transform infrared spectroscopy. The encapsulation efficiency and sustained release rate of RL-QN15 from the nanocomposites were determined. The prohealing potency of nanocomposites were evaluated by full-thickness injured wounds in both mice and swine and burn wounds in mice.

RESULTS

Our results indicated that, compared with RL-QN15 alone, the prohealing potency of nanocomposites of MPDA and RL-QN15 in the full-thickness injured wounds and burn wounds in mice was increased by up to 50 times through the slow release of RL-QN15. Moreover, the load on the MPDA obviously increased the prohealing activities of RL-QN15 in full-thickness injured wounds in swine. In addition, the obvious increase in the prohealing potency of nanocomposites of MPDA and RL-QN15 was also proved by the results from histological analysis.

CONCLUSIONS

Based on our knowledge, this is the first research to report that the load of MPDA nanoparticles could significantly increase the prohealing potency of peptide and hence highlighted the promising potential of MPDA nanoparticles-carrying peptide RL-QN15 for skin wound therapy.

Occurrence, spatial distribution, source, and ecological risk assessment of organochlorine pesticides in Dongting Lake, China

The occurrence, distribution, sources, and ecological risks of organochlorine pesticides in Dongting Lake of China were investigated. The average concentrations of organochlorine pesticides (OCPs) in 22 surface water samples and 14 sediment samples were 90.07 ng/L and 80.65 ng/g dw, respectively. Sixteen types of OCPs, dominated by HCHs, DDTs and heptachlor, were detected in the Dongting Lake. The relationships of OCP residues between Dongting Lake and its tributary rivers have been discussed and the hydraulic connections with the Yangtze River and the Three Gorges Dam (TGD) were also considered. Results showed that the shortage of runoff, earlier dry season, and reduction of sediment deposition extremely deteriorated the hydraulic conditions, magnified the water cycle, and restrained the self-purification of OCPs. The ∑OCPs in surface water were concentrated in the inlets of Yangtze River, Lishui River, Zishui River, Yuanshui River, and Xiangjiang River. Moreover, the ∑OCPs in the outlet of the Yangtze River also maintained a high level, indicating that OCPs posed adverse effects on the Yangtze River. Risk assessments of OCPs in the surface water of Dongting Lake were estimated according to available water quality guidelines and health risk assessment models. The results indicated that OCPs in the surface water of Dongting Lake were safe for aquatic organisms and human health. In addition, sediment quality guidelines (SQGs) were also applied to evaluate the potential ecotoxicological risks of OCPs in sediments. The results presented that contaminants of γ-HCH; o,p'-DDD; and dieldrin in sediment had adverse effects on benthic organisms, indicating that fundamental solutions should be proposed to control OCP contamination in Dongting Lake.

Ventilation and air cleaning to limit aerosol particle concentrations in a gym during the COVID-19 pandemic

SARS-CoV-2 can spread by close contact through large droplet spray and indirect contact via contaminated objects. There is mounting evidence that it can also be transmitted by inhalation of infected saliva aerosol particles. These particles are generated when breathing, talking, laughing, coughing or sneezing. It can be assumed that aerosol particle concentrations should be kept low in order to minimize the potential risk of airborne virus transmission. This paper presents measurements of aerosol particle concentrations in a gym, where saliva aerosol production is pronounced. 35 test persons performed physical exercise and aerosol particle concentrations, CO₂ concentrations, air temperature and relative humidity were obtained in the room of 886 m³. A separate test was used to discriminate between human endogenous and exogenous aerosol particles. Aerosol particle removal by mechanical ventilation and mobile air cleaning units was measured. The gym test showed that ventilation with air-change rate ACH = 2.2 h^-1, i.e. 4.5 times the minimum of the Dutch Building Code, was insufficient to stop the significant aerosol concentration rise over 30 min. Air cleaning alone with ACH = 1.39 h^-1 had a similar effect as ventilation alone. Simplified mathematical models were engaged to provide further insight into ventilation, air cleaning and deposition. It was shown that combining the above-mentioned ventilation and air cleaning can reduce aerosol particle concentrations with 80 to 90% , depending on aerosol size. This combination of existing ventilation supplemented with air cleaning is energy efficient and can also be applied for other indoor environments.

High-throughput sequencing of the porcine antibody repertoire with or without PEDV infection: A proof-of-concept study

A host's adaptive immune system can protect against a wide variety of pathogens by producing diverse antibodies. The antibody repertoire is so vast that traditional low-throughput methods cannot fully sequence it. In this study, we developed a high-throughput sequencing (HTS) method for antibody repertoire assessment in swine, and tested it with or without porcine epidemic diarrhea virus (PEDV) infection. We isolated peripheral blood mononuclear cells from normal or PEDV-seropositive pigs and applied multiplex PCR to amplify the porcine B cell receptor heavy chain library, followed by HTS using the Illumina Miseq system to obtain full sequence information. The results from sequence analysis demonstrated that in normal conditions, several V gene segments were preferentially used, with IGHV1-4 and IGHV1S2 being the two most frequent. The IGHV usage in PEDV-seropositive pigs was not exactly the same as that of PEDV-seronegative pigs, with an increased usage of IGHV1-6. Our study provides an effective approach to comprehensively understand the overall porcine antibody repertoire, as well as to monitor broad antibody responses to viral challenge in pigs.

Identification of Potential Early Diagnostic Biomarkers of Sepsis

Objective

The goal of this article was to identify potential biomarkers for early diagnosis of sepsis in order to improve their survival.

Methods

We analyzed differential gene expression between adult sepsis patients and controls in the GSE54514 dataset. Coexpression analysis was used to cluster coexpression modules, and enrichment analysis was performed on module genes. We also analyzed differential gene expression between neonatal sepsis patients and controls in the GSE25504 dataset, and we identified the subset of differentially expressed genes (DEGs) common to neonates and adults. All samples in the GSE54514 dataset were randomly divided into training and validation sets, and diagnostic signatures were constructed using least absolute shrink and selection operator (LASSO) regression. The key gene signature was screened for diagnostic value based on area under the receiver operating characteristic curve (AUC). STEM software identified dysregulated genes associated with sepsis-associated mortality. The ssGSEA method was used to quantify differences in immune cell infiltration between sepsis and control samples.

Results

A total of 6316 DEGs in GSE54514 were obtained spanning 10 modules. Module genes were mainly enriched in immune and metabolic responses. Screening 51 genes from among common genes based on AUC > 0.7 led to a LASSO model for the training set. We obtained a 25-gene signature, which we validated in the validation set and in the GSE25504 dataset. Among the signature genes, SLC2A6, C1ORF55, DUSP5 and RHOB were recognized as key genes (AUC > 0.75) in both the GSE54514 and GSE25504 datasets. SLC2A6 was identified by STEM as associated with sepsis-associated mortality and showed the strongest positive correlation with infiltration levels of Th1 cells.

Conclusion

In summary, our four key genes may have important implications for the early diagnosis of sepsis patients. In particular, SLC2A6 may be a critical biomarker for predicting survival in sepsis.

Lysosomal ion channels involved in cellular entry and uncoating of enveloped viruses: Implications for therapeutic strategies against SARS-CoV-2

Ion channels are necessary for correct lysosomal function including degradation of cargoes originating from endocytosis. Almost all enveloped viruses, including coronaviruses (CoVs), enter host cells via endocytosis, and do not escape endosomal compartments into the cytoplasm (via fusion with the endolysosomal membrane) unless the virus-encoded envelope proteins are cleaved by lysosomal proteases. With the ongoing outbreak of severe acute respiratory syndrome (SARS)-CoV-2, endolysosomal two-pore channels represent an exciting and emerging target for antiviral therapies. This review focuses on the latest knowledge of the effects of lysosomal ion channels on the cellular entry and uncoating of enveloped viruses, which may aid in development of novel therapies against emerging infectious diseases such as SARS-CoV-2.

Simultaneous, Rapid and Nondestructive Determination of Moisture, Fat Content and Storage Time in Leisure Dried Tofu Using LF-NMR

Leisure dried tofu is a kind of small packaged food which is popular with consumers in China. However, during the storage of leisure dried tofu, moisture and fat may be lost and deteriorate. For their own benefit, bad business operators might forge or mark the production date and shelf life. Therefore, it is necessary to explore a method to determine simultaneously the moisture, fat content, and storage time of leisure dried tofu. Samples were measured for obtaining transverse relaxation data by using low-field nuclear magnetic resonance (LF-NMR) spectrometer. The experimental data were analyzed and modeled by methods including partial least squares (PLS) or back-propagation artificial neural network (BP-ANN). The results show that the models can be used to predict the moisture, fat content, and storage time rapidly, nondestructively, accurately, and simultaneously. Furthermore, in order to explore the changes of nutrients in leisure dried tofu with the storage time, the storage dynamics of moisture and fat was considered by a using corresponding calibration model.

A novel spike subunit 1-based enzyme-linked immunosorbent assay reveals widespread porcine torovirus infection in eastern China

Toroviruses (ToVs), closely related but genetically distinct from coronaviruses, are known to infect horses, cows, pigs, goats and humans, mainly causing enteritic disorders. However, due to the lack of an adaptive culture system, porcine ToV (PToV) has received less attention. In this study, we developed a novel serological detection method based on the PToV envelope spike subunit 1 (S1) protein for the first time, and compared it to an existing indirect enzyme-linked immunosorbent assay (ELISA) based on the nucleocapsid protein. By using the S1-based ELISA, we carried out the first seroepidemiological survey of PToV in China, assaying both specific IgG and IgA responses in 1,037 serum samples collected from diarrheic pigs in eastern China. There was a relatively high incidence of seropositivity in pigs of different ages, especially one-week-old piglets and sows (78% and 43%), the former probably reflecting maternal antibodies. Furthermore, 3/20 (15%) of faecal samples collected from one PToV-seropositive swine herd in Zhejiang province tested positive by RT-PCR. The complete PToV genome was sequenced from one of these samples, and its phylogenetic relationship with other full-length PToV sequences available in GenBank was determined. Our data provide the first serological evidence for PToV infection in pigs from China, which will help elucidate the potential pathogenicity of PToV in pigs.

The porcine deltacoronavirus accessory protein NS6 is expressed in vivo and incorporated into virions

Porcine deltacoronavirus (PDCoV) is one of the emerged coronaviruses posing a significant threat to the swine industry. Previous work showed the presence of a viral accessory protein NS6 in PDCoV-infected cells. In this study, we detected the expression of the NS6 protein in small intestinal tissues of PDCoV-infected piglets. In addition, SDS-PAGE and Western blot analysis of sucrose gradient-purified virions showed the presence of a 13-kDa NS6 protein. Further evidences of the presence of NS6 in the PDCoV virions were obtained by immunogold staining of purified virions with anti-NS6 antiserum, and by immunoprecipitation of NS6 from purified virions. Finally, the anti-NS6 antibody was not able to neutralize PDCoV in cultured cells. These data establish for the first time that the accessory protein NS6 is expressed during infection in vivo and incorporated into PDCoV virions.

Occurrence and risk evaluation of organophosphorus pesticides in typical water bodies of Beijing, China

AbstractHuman activities, particularly in large cities, can lead to pollution caused by micropollutants such as pesticides in water bodies, which have been recognized as serious threats to the environment and human health. The pollution level of six organophosphorus pesticides, three herbicides, and one bactericide in groundwater and the Wenyu River, and their fates in three sewage treatment plants (STPs) and a hospital were investigated in this study. The concentrations of the ten detected pesticides ranged from not detected (ND) to 323.44 ng L^-1 in different water samples from Beijing; metalaxyl was detected to have the highest concentration (89.58 ng L^-1), and the detection frequencies of atrazine and metalaxyl were 100%. The maximum concentrations of pesticides in the Wenyu River, STPs, and the hospital were 1-2 orders of magnitude higher than those in the groundwater. Good removal efficiencies by the treatment processes were observed for ametryn (100%), while the removal efficiencies for atrazine and omethoate were the lowest in the three STPs (- 9.6% and 12.67%, respectively). Finally, risk quotient (RQ) values of each contaminant were estimated from the maximum values determined for typical urban to assess the ecology and health effects. In the case of environmental toxicity, the highest RQ values (> 1) were obtained for dichlorvos and omethoate. In the case of health toxicity, the RQ values show that the pesticides found in groundwater pose no potential health risks to humans at current concentrations.

Removal of tri-(2-chloroisopropyl) phosphate (TCPP) by three types of constructed wetlands

In this study, three types of constructed wetlands (CWs) (biofilm-attachment-surface-CWs, packed bed-CWs and traditional-CWs) were assembled to comparatively evaluate their ability and mechanism to remove tri-(2-chloroisopropyl) phosphate (TCPP) under continuous flow operation. The removal rate (26%-28%) of TCPP in two types of CWs containing plants was twice as much as that in plant-free CWs in 6-month experiments, and TCPP showed a terminal accumulation phenomenon in Cyperus alternifolius with the order of accumulation of leaf>stem>root. The mass balance indicated that the contributions of filler and hydrophyte absorption to TCPP removal were less than 1%, but the transpiration of hydrophytes may make an important contribution (approximately 10%) to TCPP removal. Species in the genera Massilia, Denitratisoma and SM1A02 may be responsible for TCPP biodegradation. In addition, the effect of TCPP on the metabolic pathways and energy generation in the roots of C. alternifolius suggested that TCPP may be transported and utilized through cellular metabolism.

Discovery of a novel short peptide with efficacy in accelerating the healing of skin wounds

Despite extensive efforts to develop efficacious therapeutic approaches, the treatment of skin wounds remains a considerable clinical challenge. Existing remedies cannot sufficiently meet current needs, so the discovery of novel pro-healing agents is of growing importance. In the current research, we identified a novel short peptide (named RL-QN15, primary sequence 'QNSYADLWCQFHYMC') from Rana limnocharis skin secretions, which accelerated wound healing in mice. Exploration of the underlying mechanisms showed that RL-QN15 activated the MAPK and Smad signaling pathways, and selectively modulated the secretion of cytokines from macrophages. This resulted in the proliferation and migration of skin cells and dynamic regulation of TGF-β1 and TGF-β3 in wounds, which accelerated re-epithelialization and granulation tissue formation and thus skin regeneration. Moreover, RL-QN15 showed significant therapeutic potency against chronic wounds, skin fibrosis, and oral ulcers. Our results highlight frog skin secretions as a potential treasure trove of bioactive peptides with healing activity. The novel peptide (RL-QN15) identified in this research shows considerable capacity as a candidate for the development of novel pro-healing agents.

FI-Net: Identification of Cancer Driver Genes by Using Functional Impact Prediction Neural Network

Identification of driver genes, whose mutations cause the development of tumors, is crucial for the improvement of cancer research and precision medicine. To overcome the problem that the traditional frequency-based methods cannot detect lowly recurrently mutated driver genes, researchers have focused on the functional impact of gene mutations and proposed the function-based methods. However, most of the function-based methods estimate the distribution of the null model through the non-parametric method, which is sensitive to sample size. Besides, such methods could probably lead to underselection or overselection results. In this study, we proposed a method to identify driver genes by using functional impact prediction neural network (FI-net). An artificial neural network as a parametric model was constructed to estimate the functional impact scores for genes, in which multi-omics features were used as the multivariate inputs. Then the estimation of the background distribution and the identification of driver genes were conducted in each cluster obtained by the hierarchical clustering algorithm. We applied FI-net and other 22 state-of-the-art methods to 31 datasets from The Cancer Genome Atlas project. According to the comprehensive evaluation criterion, FI-net was powerful among various datasets and outperformed the other methods in terms of the overlap fraction with Cancer Gene Census and Network of Cancer Genes database, and the consensus in predictions among methods. Furthermore, the results illustrated that FI-net can identify known and potential novel driver genes.

CheXLocNet: Automatic localization of pneumothorax in chest radiographs using deep convolutional neural networks

BACKGROUND

Pneumothorax can lead to a life-threatening emergency. The experienced radiologists can offer precise diagnosis according to the chest radiographs. The localization of the pneumothorax lesions will help to quickly diagnose, which will be benefit for the patients in the underdevelopment areas lack of the experienced radiologists. In recent years, with the development of large neural network architectures and medical imaging datasets, deep learning methods have become a methodology of choice for analyzing medical images. The objective of this study was to the construct convolutional neural networks to localize the pneumothorax lesions in chest radiographs.

METHODS AND FINDINGS

We developed a convolutional neural network, called CheXLocNet, for the segmentation of pneumothorax lesions. The SIIM-ACR Pneumothorax Segmentation dataset was used to train and validate CheXLocNets. The training dataset contained 2079 radiographs with the annotated lesion areas. We trained six CheXLocNets with various hyperparameters. Another 300 annotated radiographs were used to select parameters of these CheXLocNets as the validation set. We determined the optimal parameters by the AP50 (average precision at the intersection over union (IoU) equal to 0.50), a segmentation evaluation metric used by several well-known competitions. Then CheXLocNets were evaluated by a test set (1082 normal radiographs and 290 disease radiographs), based on the classification metrics: area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and positive predictive value (PPV); segmentation metrics: IoU and Dice score. For the classification, CheXLocNet with best sensitivity produced an AUC of 0.87, sensitivity of 0.78 (95% CI 0.73-0.83), and specificity of 0.78 (95% CI 0.76-0.81). CheXLocNet with best specificity produced an AUC of 0.79, sensitivity of 0.46 (95% CI 0.40-0.52), and specificity of 0.92 (95% CI 0.90-0.94). For the segmentation, CheXLocNet with best sensitivity produced an IoU of 0.69 and Dice score of 0.72. CheXLocNet with best specificity produced an IoU of 0.77 and Dice score of 0.79. We combined them to form an ensemble CheXLocNet. The ensemble CheXLocNet produced an IoU of 0.81 and Dice score of 0.82. Our CheXLocNet succeeded in automatically detecting pneumothorax lesions, without any human guidance.

CONCLUSIONS

In this study, we proposed a deep learning network, called, CheXLocNet, for the automatic segmentation of chest radiographs to detect pneumothorax. Our CheXLocNets generated accurate classification results and high-quality segmentation masks for the pneumothorax at the same time. This technology has the potential to improve healthcare delivery and increase access to chest radiograph expertise for the detection of diseases. Furthermore, the segmentation results can offer comprehensive geometric information of lesions, which can benefit monitoring the sequential development of lesions with high accuracy. Thus, CheXLocNets can be further extended to be a reliable clinical decision support tool. Although we used transfer learning in training CheXLocNet, the parameters of CheXLocNet was still large for the radiograph dataset. Further work is necessary to prune CheXLocNet suitable for the radiograph dataset.

Behavior of selected organophosphate flame retardants (OPFRs) and their influence on rhizospheric microorganisms after short-term exposure in integrated vertical-flow constructed wetlands (IVCWs)

Considering its ubiquitous occurrence and potential adverse effects of organophosphorus flame retardant (OPFR), it is urgent to explore the efficient treatment for OPFRs wastewater. Thus, integrated vertical-flow constructed wetlands (IVCWs) were set up to comparatively evaluate their nitrogen removal capacity under tidal flow operations and to investigate environmental behavior and rhizosphere microbial responses after short-term exposure to three OPFRs. The results show that IVCWs have an excellent TN removal rate (628.13 ± 110.63 mg m^-2 d^-1) and moderate mitigation efficiencies (48.37 ± 9.52 to 82.28 ± 7.48%) for target OPFRs when treating low-C/N ratio wastewater. Moreover, the sorption of selected OPFRs to soil (28.85-308.41 ng g^-1, dry weight (dw)), igneous rock (659.85-970.80 ng g^-1 dw) and zeolite (1045.60-1351.70 ng g^-1 dw) and accumulation in tissues of C. alternifolius (0-289.68 ng g^-1 dw) and P. australis (0.56-108.22 ng g^-1 dw) showed a hydrophobicity-specific feature. Namely, the highly hydrophobic compound tricresyl phosphate (TCrP) partitioned preferentially to sediment, and the chlorinated analytes were more easily taken up and then translocated into the plant body. Simultaneously, further mass balance analysis revealed the fate of OPFRs in IVCW components. A total of 53.25% of the highly hydrophobic TCrP inflow mass settled in sediment, while tris (2-chloroethyl) phosphate (TCEP) and tris (1-chloro-2-propyl) phosphate (TCPP) were more liable to discharge (35.33-50.89%) and other pathways (38.77-39.87%). Furthermore, the abundance of aerobic denitrifying bacteria (AD) in rhizosphere soil (2.25-5.12%), jointly with the prevalence of nitrobacteria (NOBs, 1.84-13.60%) and denitrifying bacteria (DNBs, 5.84-7.89%) in sublayer matrices, was responsible for superior TN removal. Additionally, the rhizosphere microbial richness, diversity and nitrogen-related microorganisms were clearly influenced by the presence of OPFRs. Notably, the genera Pseudomonas and Sphingobium might be the functional microorganisms for mixture OPFRs biodegradation.

Trypsin promotes porcine deltacoronavirus mediating cell-to-cell fusion in a cell type-dependent manner

Porcine deltacoronavirus (PDCoV) is a newly emerging threat to the global porcine industry. PDCoV has been successfully isolated using various medium additives including trypsin, and although we know it is important for viral replication, the mechanism has not been fully elucidated. Here, we systematically investigated the role of trypsin in PDCoV replication including cell entry, cell-to-cell membrane fusion and virus release. Using pseudovirus entry assays, we demonstrated that PDCoV entry is not trypsin dependent. Furthermore, unlike porcine epidemic diarrhea virus (PEDV), in which trypsin is important for the release of virus from infected cells, PDCoV release was not affected by trypsin. We also demonstrated that trypsin promotes PDCoV replication by enhancing cell-to-cell membrane fusion. Most importantly, our study illustrates two distinct spreading patterns from infected cells to uninfected cells during PDCoV transmission, and the role of trypsin in PDCoV replication in cells with different virus spreading types. Overall, these results clarify that trypsin promotes PDCoV replication by mediating cell-to-cell fusion transmission but is not crucial for viral entry. This knowledge can potentially contribute to improvement of virus production efficiency in culture, not only for vaccine preparation but also to develop antiviral treatments.

Characterization of a novel bat-HKU2-like swine enteric alphacoronavirus (SeACoV) infection in cultured cells and development of a SeACoV infectious clone

Swine enteric alphacoronavirus (SeACoV), also known as swine acute diarrhea syndrome coronavirus (SADS-CoV), belongs to the species Rhinolophus bat coronavirus HKU2. Herein, we report on the primary characterization of SeACoV in vitro. Four antibodies against the SeACoV spike, membrane, nucleocapsid and nonstructural protein 3 capable of reacting with viral antigens in SeACoV-infected Vero cells were generated. We established a DNA-launched SeACoV infectious clone based on the cell adapted passage-10 virus and rescued the recombinant virus with a unique genetic marker in cultured cells. Six subgenomic mRNAs containing the leader-body junction sites, including a bicistronic mRNA encoding the accessory NS7a and NS7b genes, were experimentally identified in SeACoV-infected cells. Cellular ultrastructural changes induced by SeACoV infection were visualized by electron microscopy. The availability of the SeACoV infectious clone and a panel of antibodies against different viral proteins will facilitate further studies on understanding the molecular mechanisms of SeACoV replication and pathogenesis.

Specific recombinant proteins of porcine epidemic diarrhea virus are immunogenic, revealing their potential use as diagnostic markers

Given the highly contagious and acute nature of porcine epidemic diarrhea (PED), especially in piglets, there is an urgent need for the development of rapid and sensitive diagnostic assays. The diagnostic potentials of specific porcine epidemic diarrhea virus (PEDV) accessory and nonstructural proteins, if any, have not yet been investigated. In order to determine and compare which of the viral proteins may be useful as diagnostic antigens, whole virus (WV) particles and a panel of structural and nonstructural PEDV proteins [spike subunit 1 (S1), the C-terminal part of ORF3 (ORF3C), envelope (E), nonstructural protein 1 (Nsp1), Nsp2, Ac (acidic domain of Nsp3), and ADRP (ADP-ribose-1-monophosphatase domain of Nsp3), expressed individually in bacterial and/or mammalian cells] were tested for reactivity with sera from PEDV-infected pigs by ELISA and/or western blot analysis. According to western blots, serum antibody interactions with the S1 protein were relatively more sensitive and specific than ORF3C, E and Ac. Furthermore, a total of 851 serum samples from diarrheal pigs of different ages were analyzed by ELISA, with most showing immune-reactivity towards the WV, S1, ORF3C, and E proteins. The earliest IgG antibody response was observed in the one-week-old piglets, with similar antibody ontogeny and patterns of seroconversion for S1, ORF3C, E, and WV antigens. In addition, the pattern of neutralizing antibody was more similar to that of IgA in weaning piglets after PEDV infection. Collectively, these data provide more reliable information on the host immune response to different viral proteins, which will be useful for development of novel serological assays and for design of vaccines that better stimulate protective immunity.

Inhibition of SGK1 confers vulnerability to redox dysregulation in cervical cancer

Cervical cancer has poor prognosis and patients are often diagnosed at advanced stages of the disease with limited treatment options. There is thus an urgent need for the discovery of new therapeutic strategies in cervical cancer. The activation of SGK1 has been linked to the development of various cancer types but little is known about the role of SGK1 in cervical cancer and its potential as a therapeutic target. Here we report that SGK1 is an antioxidative factor that promotes survival of cervical cancer cells. Gene set enrichment analysis of RNA-Seq data reveals a strong inverse association between SGK1 and oxidative phosphorylation. Consistently, inhibition of SGK1 via siRNA or pharmacological inhibitor GSK650394 induces ROS and cytotoxicity upon H₂O₂ stress. Further analysis of clinical data associates SGK1 with gene expression signatures regulated by the antioxidant transcription factor NRF2 in cervical cancer. Mechanistically, SGK1 activation exerts antioxidant effect through induction of c-JUN-dependent NRF2 expression and activity. Importantly, we find that inhibition of SGK1 confers vulnerability to melatonin as a pro-oxidant, resulting in ROS over-accumulation and consequently enhanced cell cytotoxicity. We further demonstrate that combined use of GSK650394 and melatonin yields substantial regression of cervical tumors in vivo. This work opens new perspectives on the potential of SGK1 inhibitors as sensitizing agents to enable the design of therapeutically redox-modulating strategies against cervical cancer.

Characteristics of the Life Cycle of Porcine Deltacoronavirus (PDCoV) In Vitro: Replication Kinetics, Cellular Ultrastructure and Virion Morphology, and Evidence of Inducing Autophagy

Porcine deltacoronavirus (PDCoV) causes severe diarrhea and vomiting in affected piglets. The aim of this study was to establish the basic, in vitro characteristics of the life cycle such as replication kinetics, cellular ultrastructure, virion morphology, and induction of autophagy of PDCoV. Time-course analysis of viral subgenomic and genomic RNA loads and infectious titers indicated that one replication cycle of PDCoV takes 5 to 6 h. Electron microscopy showed that PDCoV infection induced the membrane rearrangements with double-membrane vesicles and large virion-containing vacuoles. The convoluted membranes structures described in alpha- and beta-coronavirus were not observed. PDCoV infection also increased the number of autophagosome-like vesicles in the cytoplasm of cells, and the autophagy response was detected by LC3 I/II and p62 Western blot analysis. For the first time, this study presents the picture of the PDCoV infection cycle, which is crucial to help elucidate the molecular mechanism of deltacoronavirus replication.