Differences in resting-state brain activity in first-episode drug-naïve major depressive disorder patients with and without suicidal ideation.

Despite altered brain activities being associated with suicidal ideation (SI), the neural correlates of SI in major depressive disorder (MDD) have remained elusive. We enrolled 82 first-episode drug-naïve MDD patients including 41 with SI and 41 without SI, as well as 41 healthy controls (HCs). Resting-state functional and structural MRI data were collected. The measures of fractional amplitude of low-frequency fluctuation (fALFF) and grey matter volume (GMV) were calculated and compared. Compared with HCs, patients with SI exhibited increased fALFF values in the right rectus gyrus and left medial superior frontal gyrus, middle frontal gyrus and precuneus. Decreased GMV in the right parahippocampal gyrus, insula and middle occipital gyrus and increased GMV in the left superior frontal gyrus were detected in patients with SI. In addition, patients without SI demonstrated increased fALFF values in the right superior frontal gyrus and decreased fALFF values in the right postcentral gyrus. Decreased GMV in the left superior frontal gyrus, right medial superior frontal gyrus, opercular part of inferior frontal gyrus, postcentral gyrus, fusiform gyrus and increased left supplementary motor area, superior occipital gyrus, right anterior cingulate gyrus and superior temporal gyrus were revealed in patients with SI. Moreover, in comparison with patients without SI, increased fALFF values were identified in the left precuneus of patients with SI. However, no significant differences were found in GMV between patients with and without SI. These findings might be helpful for finding neuroimaging markers predicting individual suicide risk and detecting targeted brain regions for effective early interventions.

Spatiotemporal encoding MRI in a portable low-field system.

PURPOSE: Demonstrate the potential of spatiotemporal encoding (SPEN) MRI to deliver largely undistorted 2D, 3D, and diffusion weighted images on a 110 mT portable system. METHODS: SPEN's quadratic phase modulation was used to subsample the low-bandwidth dimension of echo planar acquisitions, delivering alias-free images with an enhanced immunity to image distortions in a laboratory-built, low-field, portable MRI system lacking multiple receivers. RESULTS: Healthy brain images with different SPEN time-bandwidth products and subsampling factors were collected. These compared favorably to EPI acquisitions including topup corrections. Robust 3D and diffusion weighted SPEN images of diagnostic value were demonstrated, with 2.5 mm isotropic resolutions achieved in 3 min scans. This performance took advantage of the low specific absorption rate and relative long TEs associated with low-field MRI. CONCLUSION: SPEN MRI provides a robust and advantageous fast acquisition approach to obtain faithful 3D images and DWI data in low-cost, portable, low-field systems without parallel acceleration.

Quantitative anatomical analysis of lumbar interspaces based on 3D CT imaging: optimized segment selection for lumbar puncture in different age groups.

BACKGROUND: Optimal lumbar puncture segment selection remains controversial. This study aims to analyze anatomical differences among L3-4, L4-5, and L5-S1 segments across age groups and provide quantitative evidence for optimized selection. METHODS: 80 cases of CT images were collected with patients aged 10-80 years old. Threedimensional models containing L3-S1 vertebrae, dural sac, and nerve roots were reconstructed. Computer simulation determined the optimal puncture angles for the L3-4, L4-5, and L5-S1 segments. The effective dural sac area (ALDS), traversing nerve root area (ATNR), and area of the lumbar inter-laminar space (ALILS) were measured. Puncture efficacy ratio (ALDS/ALILS) and nerve injury risk ratio (ATNR/ALILS) were calculated. Cases were divided into four groups: A (10-20 years), B (21-40 years), C (41-60 years), and D (61-80 years). Statistical analysis was performed using SPSS. RESULTS: 1) ALDS was similar among segments; 2) ATNR was greatest at L5-S1; 3) ALILS was greatest at L5-S1; 4) Puncture efficacy ratio was highest at L3-4 and lowest at L5-S1; 5) Nerve injury risk was highest at L5-S1. In group D, L5-S1 ALDS was larger than L3-4 and L4-5. ALDS decreased after age 40. Age variations were minimal across parameters. CONCLUSION: The comprehensive analysis demonstrated L3-4 as the optimal first-choice segment for ages 10-60 years, conferring maximal efficacy and safety. L5-S1 can serve as an alternative option for ages 61-80 years when upper interspaces narrow. This study provides quantitative imaging evidence supporting age-specific, optimized lumbar puncture segment selection.

EspP2 Regulates the Adhesion of Glaesserella parasuis via Rap1 Signaling Pathway.

Different levels of EspP2 expression are seen in strains of Glaesserella parasuis with high and low pathogenicity. As a potential virulence factor for G. parasuis, the pathogenic mechanism of EspP2 in infection of host cells is not clear. To begin to elucidate the effect of EspP2 on virulence, we used G. parasuis SC1401 in its wild-type form and SC1401, which was made EspP2-deficient. We demonstrated that EspP2 causes up-regulation of claudin-1 and occludin expression, thereby promoting the adhesion of G. parasuis to host cells; EspP2-deficiency resulted in significantly reduced adhesion of G. parasuis to cells. Transcriptome sequencing analysis of EspP2-treated PK15 cells revealed that the Rap1 signaling pathway is stimulated by EspP2. Blocking this pathway diminished occludin expression and adhesion. These results indicated that EspP2 regulates the adhesion of Glaesserella parasuis via Rap1 signaling pathway.

Understanding aliasing effects and their removal in SPEN MRI: A k-space perspective.

PURPOSE: To characterize the mechanism of formation and the removal of aliasing artifacts and edge ghosts in spatiotemporally encoded (SPEN) MRI within a k-space theoretical framework. METHODS: SPEN's quadratic phase modulation can be described in k-space by a convolution matrix whose coefficients derive from Fourier relations. This k-space model allows us to pose SPEN's reconstruction as a deconvolution process from which aliasing and edge ghost artifacts can be quantified by estimating the difference between a full sampling and reconstructions resulting from undersampled SPEN data. RESULTS: Aliasing artifacts in SPEN MRI reconstructions can be traced to image contributions corresponding to high-frequency k-space signals. The k-space picture provides the spatial displacements, phase offsets, and linear amplitude modulations associated to these artifacts, as well as routes to removing these from the reconstruction results. These new ways to estimate the artifact priors were applied to reduce SPEN reconstruction artifacts on simulated, phantom, and human brain MRI data. CONCLUSION: A k-space description of SPEN's reconstruction helps to better understand the signal characteristics of this MRI technique, and to improve the quality of its resulting images.

High-resolution multi-shot diffusion-weighted MRI combining markerless prospective motion correction and locally low-rank constrained reconstruction.

PURPOSE: Subject head motion is a major challenge in DWI, leading to image blurring, signal losses, and biases in the estimated diffusion parameters. Here, we investigate a combined application of prospective motion correction and spatial-angular locally low-rank constrained reconstruction to obtain robust, multi-shot, high-resolution diffusion-weighted MRI under substantial motion. METHODS: Single-shot EPI with retrospective motion correction can mitigate motion artifacts and resolve any mismatching of gradient encoding orientations; however, it is limited by low spatial resolution and image distortions. Multi-shot acquisition strategies could achieve higher resolution and image fidelity but increase the vulnerability to motion artifacts and phase variations related to cardiac pulsations from shot to shot. We use prospective motion correction with optical markerless motion tracking to remove artifacts and reduce image blurring due to bulk motion, combined with locally low-rank regularization to correct for remaining artifacts due to shot-to-shot phase variations. RESULTS: The approach was evaluated on healthy adult volunteers at 3 Tesla under different motion patterns. In multi-shot DWI, image blurring due to motion with 20 mm translations and 30° rotations was successfully removed by prospective motion correction, and aliasing artifacts caused by shot-to-shot phase variations were addressed by locally low-rank regularization. The ability of prospective motion correction to preserve the orientational information in DTI without requiring a reorientation of the b-matrix is highlighted. CONCLUSION: The described technique is proved to hold valuable potential for mapping brain diffusivity and connectivity at high resolution for studies in subjects/cohorts where motion is common, including neonates, pediatrics, and patients with neurological disorders.

Pseudo multishot echo-planar imaging for geometric distortion improvement.

Conventional echo-planar imaging (EPI) uses a radiofrequency pulse for excitation and a prolonged echo train to sample k space, while off-resonance and T2 * decay effects caused by magnetic susceptibility variation accumulate within each echo, leading to geometric distortion. Multishot EPI methods, which divide k space into segments, can shorten the effective echo spacing and reduce the distortion on EPI images. But multiple shots cost longer scan time and render susceptibility to motion. In this study, we propose a new "multishot" EPI method termed pseudo multishot EPI (pmsEPI), in which phase-encoding lines are segmented as in multishot EPI but are collected within a single shot. With the magnetization divided into different pathways via interleaved excitation instead of refocusing in a single long echo train, the total phase error accumulation is reduced in each segmented acquisition, thereby improving distortion of the resultant EPI image. The performance of the pmsEPI method is demonstrated by phantom and in vivo brain experiments on a 3-T scanner. The experimental results show that the distortion displacements of pmsEPI acquisition compared with conventional EPI decrease by 50% with two pseudo shots and 66% with three pseudo shots, validating the ability of the method to obtain images with reduced distortion in a single shot, although magnetization splitting may induce more than 40% SNR loss and minor artifacts. Specifically, the ability of pmsEPI in diffusion-weighted imaging with different trajectory options is highlighted, and the flexibility is demonstrated in a single-shot blip up and down acquisition.

Structural characteristics of a low molecular weight velvet antler protein and the anti-tumor activity on S180 tumor-bearing mice.

Velvet antler is a traditional Chinese medicine with various pharmacological values, which is an important raw material for traditional Chinese medicinal wine. Nevertheless, the chemical compositions and bioactivities of velvet antler residue used for making medicinal wine are rarely reported, leading to a waste of resources. In this study, a velvet antler protein (VA-pro) was extracted from velvet antler residue by simulating the gastrointestinal digestion, and its composition, structural characteristics and in vivo anti-tumor activities were determined and investigated. VA-pro possessed high purity with a relatively low molecular weight as 22.589 kDa under HPLC, one- and two-dimensional electrophoresis, and it contained high contents of Pro, Gly, Glu and Ala. Besides, the secondary structure of VA-pro was dominated by ß-turn and ß-sheet, and VA-pro possessed similar protein sequence, isoelectric point and amino acid compositions to hypothetical protein G4228_020061. The in vivo results substantiated that VA-pro could improve the body weights and immune organ indices, increase the expressions of sera cytokines and regulate the distributions of T and B lymphocytes subsets in peripheral blood of S180 tumor-bearing mice. Furthermore, VA-pro could effectively inhibit solid S180 tumors growth by inducing S phase cell cycle arrest mediated through mitochondria. To summarize, our study provided theoretical support that VA-pro had the potential to be used as an immunopotentiator in immunocompromised or cancer-bearing hosts.

Identification of a Novel Linear B-Cell Epitope of HbpA Protein from Glaesserella parasuis Using Monoclonal Antibody.

Glaesserella parasuis (G. parasuis.) is the etiological pathogen of Glässer's disease, which causes high economic losses to the pig industry. The heme-binding protein A precursor (HbpA) was a putative virulence-associated factor proposed to be potential subunit vaccine candidate in G. parasuis. In this study, three monoclonal antibodies (mAb) 5D11, 2H81, and 4F2 against recombinant HbpA (rHbpA) of G. parasuis SH0165 (serotype 5) were generated by fusing SP2/0-Ag14 murine myeloma cells and spleen cells from BALB/c mice immunized with the rHbpA. Indirect enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence assay (IFA) demonstrated that the antibody designated 5D11 showed a strong binding affinity with the HbpA protein and was chosen for subsequent experiments. The subtypes of the 5D11 were IgG1/κ chains. Western blot analysis showed that mAb 5D11 could react with all 15 serotype reference strains of G. parasuis. None of the other bacteria tested reacted with 5D11. In addition, a linear B-cell epitope recognized by 5D11 was identified by serial truncations of HbpA protein and then a series of truncated peptides were synthesized to define the minimal region that was required for mAb 5D11 binding. The 5D11 epitope was located on amino acids 324-LPQYEFNLEKAKALLA-339 by testing the 5D11 monoclonal for reactivity with 14 truncations. The minimal epitope 325-PQYEFNLEKAKALLA-339 (designated EP-5D11) was pinpointed by testing the mAb 5D11 for reactivity with a series of synthetic peptides of this region. The epitope was highly conserved among G. parasuis strains, confirmed by alignment analysis. These results indicated that mAb 5D11 and EP-5D11 might potentially be used to develop serological diagnostic tools for G. parasuis. Three-dimensional structural analysis revealed that amino acids of EP-5D11 were in close proximity and may be exposed on the surface of the HbpA protein.

Rituximab-treated patients with lymphoma develop strong CD8 T-cell responses following COVID-19 vaccination.

B-cell depletion induced by anti-cluster of differentiation 20 (CD20) monoclonal antibody (mAb) therapy of patients with lymphoma is expected to impair humoral responses to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccination, but effects on CD8 T-cell responses are unknown. Here, we investigated humoral and CD8 T-cell responses following two vaccinations in patients with lymphoma undergoing anti-CD20-mAb therapy as single agent or in combination with chemotherapy or other anti-neoplastic agents during the last 9 months prior to inclusion, and in healthy age-matched blood donors. Antibody measurements showed that seven of 110 patients had antibodies to the receptor-binding domain of the SARS-CoV-2 Spike protein 3-6 weeks after the second dose of vaccination. Peripheral blood CD8 T-cell responses against prevalent human leucocyte antigen (HLA) class I SARS-CoV-2 epitopes were determined by peptide-HLA multimer analysis. Strong CD8 T-cell responses were observed in samples from 20/29 patients (69%) and 12/16 (75%) controls, with similar median response magnitudes in the groups and some of the strongest responses observed in patients. We conclude that despite the absence of humoral immune responses in fully SARS-CoV-2-vaccinated, anti-CD20-treated patients with lymphoma, their CD8 T-cell responses reach similar frequencies and magnitudes as for controls. Patients with lymphoma on B-cell depleting therapies are thus likely to benefit from current coronavirus disease 2019 (COVID-19) vaccines, and development of vaccines aimed at eliciting T-cell responses to non-Spike epitopes might provide improved protection.

Metal Ion Periplasmic-Binding Protein YfeA of Glaesserella parasuis Induces the Secretion of Pro-Inflammatory Cytokines of Macrophages via MAPK and NF-κB Signaling through TLR2 and TLR4.

The YfeA gene, belonging to the well-conserved ABC (ATP-binding cassette) transport system Yfe, encodes the substrate-binding subunit of the iron, zinc, and manganese transport system in bacteria. As a potential vaccine candidate in Glaesserella parasuis, the functional mechanisms of YfeA in the infection process remain obscure. In this study, vaccination with YfeA effectively protected the C56BL6 mouse against the G. parasuis SC1401 challenge. Bioinformatics analysis suggests that YfeA is highly conserved in G. parasuis, and its metal-binding sites have been strictly conserved throughout evolution. Stimulation of RAW 264.7 macrophages with YfeA verified that toll-like receptors (TLR) 2 and 4 participated in the positive transcription and expression of pro-inflammatory cytokines IL-1ß, IL-6, and TNF-α. The activation of TLR2 and TLR4 utilized the MyD88/MAL and TRIF/TRAM pairs to initiate TLRs signaling. Furthermore, YfeA was shown to stimulate nuclear translocation of NF-κB and activated diverse mitogen-activated protein (MAP) kinase signaling cascades, which are specific to the secretion of particular cytokine(s) in murine macrophages. Separate blocking TLR2, TLR4, MAPK, and RelA (p65) pathways significantly decreased YfeA-induced pro-inflammatory cytokine production. In addition, YfeA-stimulated RAW 264.7 produces the pro-inflammatory hallmark, reactive oxygen species (ROS). In conclusion, our findings indicate that YfeA is a novel pro-inflammatory mediator in G. parasuis and induces TLR2 and TLR4-dependent pro-inflammatory activity in RAW 264.7 macrophages through P38, JNK-MAPK, and NF-κB signaling pathways.

The Impact of Weather and Air Pollution on Viral Infection and Disease Outcome Among Pediatric Pneumonia Patients in Chongqing, China, from 2009 to 2018: A Prospective Observational Study.

BACKGROUND: For pediatric pneumonia, the meteorological and air pollution indicators have been frequently investigated for their association with viral circulation but not for their impact on disease severity. METHODS: We performed a 10-year prospective, observational study in 1 hospital in Chongqing, China, to recruit children with pneumonia. Eight commonly seen respiratory viruses were tested. Autoregressive distributed lag (ADL) and random forest (RF) models were used to fit monthly detection rates of each virus at the population level and to predict the possibility of severe pneumonia at the individual level, respectively. RESULTS: Between 2009 and 2018, 6611 pediatric pneumonia patients were included, and 4846 (73.3%) tested positive for at least 1 respiratory virus. The patient median age was 9 months (interquartile range, 4‒20). ADL models demonstrated a decent fitting of detection rates of R2 > 0.7 for respiratory syncytial virus, human rhinovirus, parainfluenza virus, and human metapneumovirus. Based on the RF models, the area under the curve for host-related factors alone was 0.88 (95% confidence interval [CI], .87‒.89) and 0.86 (95% CI, .85‒.88) for meteorological and air pollution indicators alone and 0.62 (95% CI, .60‒.63) for viral infections alone. The final model indicated that 9 weather and air pollution indicators were important determinants of severe pneumonia, with a relative contribution of 62.53%, which is significantly higher than respiratory viral infections (7.36%). CONCLUSIONS: Meteorological and air pollution predictors contributed more to severe pneumonia in children than did respiratory viruses. These meteorological data could help predict times when children would be at increased risk for severe pneumonia and when interventions, such as reducing outdoor activities, may be warranted.

Epidemiology and Ecology of Severe Fever With Thrombocytopenia Syndrome in China, 2010‒2018.

BACKGROUND: The growing epidemics of severe fever with thrombocytopenia syndrome (SFTS), an emerging tick-borne disease in East Asia, and its high case fatality rate have raised serious public health concerns. METHODS: Surveillance data on laboratory-confirmed SFTS cases in China were collected. The spatiotemporal dynamics and epidemiological features were explored. The socioeconomic and environmental drivers were identified for SFTS diffusion using survival analysis and for SFTS persistence using a two-stage generalized boosted regression tree model. RESULTS: During 2010‒2018, a total of 7721 laboratory-confirmed SFTS cases were reported in China, with an overall case fatality rate (CFR) of 10.5%. The average annual incidence increased >20 times and endemic areas expanded from 27 to 1574 townships, whereas the CFR declined from 19% to 10% during this period. Four geographical clusters-the Changbai Mountain area, the Jiaodong Peninsula, the Taishan Mountain area, and the Huaiyangshan Mountain area-were identified. Diffusion and persistence of the disease were both driven by elevation, high coverages of woods, crops, and shrubs, and the vicinity of habitats of migratory birds but had different meteorological drivers. Residents ≥60 years old in rural areas with crop fields and tea farms were at increased risk to SFTS. CONCLUSIONS: Surveillance of SFTS and intervention programs need to be targeted at areas ecologically suitability for vector ticks and in the vicinity of migratory birds to curb the growing epidemic.

Comparative transcriptome analysis reveals that deletion of CheY influences gene expressions of ABC transports and metabolism in Haemophilus parasuis.

Haemophilus (Glaesserella) parasuis is a commensal bacterium that causes Glässer's disease (GD) in swine. As a global transcriptional factor, CheY regulates the expression of hundreds of genes in H. parasuis. In this study, we measured changes in gene expression at the whole transcriptome level using RNAseq. We identified 2058 co-expressed genes, and found 624 differentially expressed genes (q < 0.05) in ΔcheY and SC1401. Several important GO annotations and signaling pathways were identified. RNA-seq results were assembled according to the reference genome, compared with the annotated gene model, and 12 new transcriptional regions were found. Finally, q-PCR results validated the RNA-seq results with 8 randomly selected genes. The present study indicated that CheY is mainly involved in the regulation of ABC transport, oxidative phosphorylation, and ß-Lactam resistance. We draw the regulatory network of CheY, which offers greater insight into the regulatory mechanism of CheY in H.parasuis.

Identification of MHC Class Ib Ligands for Stimulatory and Inhibitory Ly49 Receptors and Induction of Potent NK Cell Alloresponses in Rats.

Early studies indicate that rats may have a repertoire of MHC class Ib-reactive Ly49 stimulatory receptors capable of mounting memory-like NK cell alloresponses. In this article, we provide molecular and functional evidence for this assumption. Pairs of Ly49 receptors with sequence similarities in the lectin-like domains, but with opposing signaling functions, showed specificity for ligands with class Ia-like structural features encoded from the first telomeric MHC class Ib gene cluster, RT1-CE, which is syntenic with the H2-D/H2-L/H2-Q cluster in mice. The activating Ly49s4 receptor and its inhibitory counterparts, Ly49i4 and Ly49i3, reacted with all allelic variants of RT1-U, whereas Ly49s5 and Ly49i5 were specific for RT1-Eu NK cell cytolytic responses were predictably activated and inhibited, and potent in vivo NK alloresponses were induced by repeated MHC class Ib alloimmunizations. Additional Ly49-class Ib interactions, including RT1-Cl with the Ly49s4/Ly49i4/Ly49i3 group of receptors, were characterized using overexpressed receptor/ligand pairs, in vitro functional assays, and limited mutational analyses. Obvious, as well as subtle, Ly49-class Ib interactions led to ligand-induced receptor calibration and NK subset expansions in vivo. Together, these studies suggest that in vivo NK alloresponses are controlled by pleomorphic Ly49-class Ib interactions, some of which may not be easily detectable in vitro.

Construction of targeted and integrative promoter-reporter plasmids pDK-K and pDK-G to measure gene expression activity in Haemophilus parasuis.

Haemophilus parasuis (H. parasuis) is rather difficult to manipulate genetically due to the diversity of restriction-modification systems and other mechanisms harbored by various isolates. This prevents exogenous plasmids from replicating in this species and hinders research efforts focused on transcriptional regulators in this bacterium. In this study, we generated a convenient promoter reporter system based on gene knock-in method using natural transformation in H. parasuis. Gene knock-in has proven useful as a powerful tool facilitating identification and studying the transcription activities of regulators under a variety of conditions that favor gene transcription or expression from an incorporated promoter. The vectors, pDK-K and pDK-G, carrying promoterless reporter lacZ gene and two homologous sequences flanking a knock-in site, may have some advantages over the extensively used plasmid-bearing reporter system in other bacteria in stability and ease of genetic manipulation in H. parasuis. The knock-in site was positioned at a site occupied by flanking genes that were both hypothetical and had the same transcription orientation, thus the expression of the reversely cloned promoter-lacZ fusion wouldn't be affected by the upstream promoter on the chromosome. The expression activity of lacZ gene under the transcriptional activation of a 300 bp promoter-proximal segment of cyaA, crp or comA genes in H. parasuis was separately validated using X-gal and o-nitrophenyl-ß-d-galactoside(ONPG) as substrates. The derivatives harboring promoter-lacZ fusion segments showed significantly higher ß-galactosidase activity levels than the promoterlessones both in TSB++ broth and on TSA++ plate as screened either by X-gal method or the standard Miller method. We also used pDK vector to further certify that the cyaA promoter is inducible and whose transcriptional levels were in correlation with the growth kinetics of the bacteria in TSB++. With this system, gene knock-in method based on natural transformation in H. parasuis proved to be useful in identifying transcriptional regulation of a certain promoter.

Complete genome sequence of a novel negevirus isolated from Culex tritaeniorhynchus in China.

A novel negevirus, tentatively named Manglie virus (MaV), was isolated from Culex tritaeniorhynchus from the village of Manglie, Yunnan, China, in August 2011. It was identified by high-throughput sequencing of cell culture supernatants, and the complete genome was sequenced using an Illumina MiSeq sequencer. The complete MaV genome comprised 9,218 nt encoding three hypothetical proteins and had a poly(A) tail. BLASTn analysis showed that the genome had the greatest similarity to Ngewotan virus strain Nepal22, with query coverage of 100% and 79% identity. Genomic and phylogenetic analyses demonstrated that MaV should be considered a novel negevirus.

The enhanced effect of supplemented lighting on nutrient removal by an aquatic vegetables (lettuce) purification system from rural domestic sewage.

Aquatic plant treatment system (APTS) is a widely used sewage purification technique; however, it requires a large area of land due to its long hydraulic retention time. In order to improve the economic value of APTS in the treatment of rural sewage, an aquatic vegetables (lettuce) purification system strengthened with a set of supplemented lighting was evaluated. The effect of supplemented lighting of blue and red light on lettuce growth and sewage purification was studied by batch experiments. The results showed that the lettuce growth and the removal rates of pollutants were enhanced by supplemented lighting, of which red light is superior to blue light, and the increase of red light intensity further promoted the growth of lettuce and the removal rate of pollutants. Supplementary light is a suitable method which could improve the purification effect of APTS in most weather conditions especially in countries where day-night light patterns change substantially between winter and summer. The results would be useful for the APTS design for treating rural domestic sewage.

The enhanced effect of activated sludge attached to the roots of Pistia stratiotes on nutrient removal for secondary effluent.

Aquatic plants are widely used for treating wastewater treatment plant secondary effluent. During this process, some residual activated sludge in the secondary effluent is intercepted and attaches to the plant roots. However, the effect of the attached activated sludge on nutrient removal in secondary effluent has up to now been unknown. Aiming at this problem, this investigation was conducted to compare the nutrient removal rates in secondary effluent by washed Pistia stratiotes (washed batch) and Pistia stratiotes with activated sludge attached to the roots (study batch). Extracellular polymeric substances (EPS) from the activated sludge attached to the roots were extracted and characterized by three-dimensional excitation emission matrix (3D-EEM) fluorescence spectroscopy. The results showed that the nutrient removal rates in the study batch were better than that in the washed batch. The 3D-EEM results showed that the protein content of EPS increased during the experiment, indicating the growth of microorganisms in the attached activated sludge. Our work demonstrated the enhanced effect of activated sludge attached to the roots of Pistia stratiotes on the removal of pollutants in secondary effluent, which is useful to guide the practical engineering of secondary effluent treatment.

A novel STAT3 inhibitor negatively modulates platelet activation and aggregation.

The signal transducer and activator of transcription 3 (STAT3) plays a critical role in platelet functions. This study sought to understand the effects of the STAT3 inhibitor SC99 on platelet activation and aggregation. Immunoblotting assays were applied to measure the effects of SC99 on the STAT3 signaling pathway. A ChronoLog aggregometer was used to evaluate platelet aggregation. A flow cytometer was used to evaluate P-selectin expression in the presence of SC99. AlamarBlue and Annexin-V staining were used to evaluate platelet viability and apoptosis, respectively. A fluorescence microscope was applied to analyze platelet spreading. SC99 inhibited the phosphorylation of JAK2 and STAT3 in human platelets but had no effects on the phosphorylation of AKT, p65 or Src, all of which are involved in platelet activation. Further studies revealed that SC99 inhibited human platelet aggregation induced by collagen and thrombin in a dose-dependent manner. SC99 inhibited thrombin-induced P-selectin expression and fibrinogen binding to single platelets. Moreover, SC99 inhibited platelet spreading on fibrinogen and clot retraction mediated by outside-in signaling. SC99 inhibited platelet aggregation in mice but it did not significantly prolong the bleeding time. Taken together, the present study revealed that SC99 inhibited platelet activation and aggregation as a STAT3 inhibitor. This agent can be developed as a promising treatment for thrombotic disorders.