Efficient biosynthesis of transglutaminase in Streptomyces mobaraensis via systematic engineering strategies.

Transglutaminases (TGases) have been widely used in food, pharmaceutical, biotechnology, and other industries because of their ability to catalyze deamidation, acyl transfer, and crosslinking reactions between Ƴ-carboxamide groups of peptides or protein-bound glutamine and the Ɛ-amino group of lysine. In this study, we demonstrated an efficient systematic engineering strategy to enhance the synthesis of TGase in a recombinant Streptomyces mobaraensis smL2020 strain in a 1000-L fermentor. Briefly, the enzymatic properties of the TGase TGL2020 from S. mobaraensis smL2020 and TGase TGLD from S. mobaraensis smLD were compared to obtain the TGase TGLD with perfected characteristics for heterologous expression in a recombinant S. mobaraensis smL2020ΔTG without the gene tgL 2020. Through multiple engineering strategies, including promoter engineering, optimizing the signal peptides and recombination sites, and increasing copies of the expression cassettes, the final TGLD activity in the recombinant S. mobaraensis smL2020ΔTG: (PL2020-spL2020-protgLD-tgLD)2 (tgL2020and BT1) reached 56.43 U/mL and 63.18 U/mL in shake flask and 1000-L fermentor, respectively, which was the highest reported to date. With the improvement of expression level, the application scope of TGLD in the food industry will continue to expand. Moreover, the genetic stability of the recombinant strain maintained at more than 20 generations. These findings proved the feasibility of multiple systematic engineering strategies in synthetic biology and provided an emerging solution to improve biosynthesis of industrial enzymes.

Harmonizing three-dimensional MRI using pseudo-warping field guided GAN.

In pursuit of cultivating automated models for magnetic resonance imaging (MRI) to aid in diagnostics, an escalating demand for extensive, multisite, and heterogeneous brain imaging datasets has emerged. This potentially introduces biased outcomes when directly applied for subsequent analysis. Researchers have endeavored to address this issue by pursuing the harmonization of MRIs. However, most existing image-based harmonization methods for MRI are tailored for 2D slices, which may introduce inter-slice variations when they are combined into a 3D volume. In this study, we aim to resolve inconsistencies between slices by introducing a pseudo-warping field. This field is created randomly and utilized to transform a slice into an artificially warped subsequent slice. The objective of this pseudo-warping field is to ensure that generators can consistently harmonize adjacent slices to another domain, without being affected by the varying content present in different slices. Furthermore, we construct unsupervised spatial and recycle loss to enhance the spatial accuracy and slice-wise consistency across the 3D images. The results demonstrate that our model effectively mitigates inter-slice variations and successfully preserves the anatomical details of the images during the harmonization process. Compared to generative harmonization models that employ 3D operators, our model exhibits greater computational efficiency and flexibility.

Oxygen evolution and its drivers in a stratified reservoir: A supply-side perspective for informing hypoxia alleviation strategies.

Hypoxia in stratified waters greatly threatens aquatic ecology and societal development owing to enhanced nutrient discharge and increasing global temperature. Current research predominantly alleviates hypoxia by reducing dissolved oxygen (DO) consumption or conducting hypolimnetic oxygenation, yet their implementation has encountered bottlenecks. Therefore, this study explores the potential of increasing the inherent DO supplies in stratified reservoirs to mitigate hypoxia. High-frequency in situ observations and massive modeling experiments are integrated to discern the DO supply mode and the dominant driver of DO evolution. Results indicate that periodic thermodynamic conditions determine the DO supply relationships between oxygen sources (inflow carriage, reaeration, and photosynthesis) for different water layers. Thermal stratification causes the hypolimnion to rely mostly on the inflow for DO supply, leading to a fragile budget prone to hypoxia. However, episodic hydrodynamic events (turnover, wind stir, density current, and flood) can promote DO supply and inhibit hypoxia. Temperature and DO regimes are primarily driven by outflow conditions, followed by inflow and meteorology conditions. Furthermore, hypolimnetic hypoxia can be regulated by altering inflow volume, outflow volume, and outlet elevation. These findings highlight the importance of longitudinal solute exchange in DO evolution in stratified reservoirs, providing a basis for alleviating hypoxia through cascade reservoir operations.

Surface segregation of rigid polyarylene ether amidoxime on polyurethane nanofiber into hierarchical membranes as substrate of flexible SERS nanosensor for sulfamethoxazole detection.

Electrospun polymeric nanofibrous membranes are emerging as the promising substrates for preparation of flexible SERS nanosensors due to their intrinsic nanoscale surface roughness, easy scalability as well as rich surface reactivity. Although the nanofiber membranes prepared from high performance thermoplastics exhibit good mechanical stability, the SERS nanosensors based on these substrates normally have lower signal-to-noise ratio because of the interference from background Raman signals of aromatic moieties. Herein, we synthesized an optically transparent polyurethane (PU) and rigid polyarylene ether amidoxime (PEA), which were electrospun into core-shell nanofibers membranes with a "beads-on-web" morphology. Furthermore, the PU-PEA membranes were coated with ultra-thin silver layer and thermally annealed to prepare the flexible SERS nanosensor without any background noises. In addition, the Raman enhancement of SERS nanosensor can be readily improved by tuning of PU-PEA composition, silver thickness as well as thermal annealing temperature. Finally, the optimized SERS nanosensor enables label-free detection of sulfamethoxazole as low as 0.1 nM with a good reproducibility and detection performance in real water sample. Meanwhile, the optimized SERS nanosensor shows long term anti-biofouling capacity. Thanks to its facile fabrication, competitive analytical performance and resistance to biofouling, the current work basically open new way for design of flexible SERS nanosensors for biomedical applications.

Learning Unified Anchor Graph for Joint Clustering of Hyperspectral and LiDAR Data.

The joint clustering of multimodal remote sensing (RS) data poses a critical and challenging task in Earth observation. Although recent advances in multiview subspace clustering have shown remarkable success, existing methods become computationally prohibitive when dealing with large-scale RS datasets. Moreover, they neglect intrinsic nonlinear and spatial interdependencies among heterogeneous RS data and lack generalization ability for out-of-sample data, thereby restricting their applicability. This article introduces a novel unified framework called anchor-based multiview kernel subspace clustering with spatial regularization (AMKSC). It learns a scalable anchor graph in the kernel space, leveraging contributions from each modality instead of seeking a consensus full graph in the feature space. To ensure spatial consistency, we incorporate a spatial smoothing operation into the formulation. The method is efficiently solved using an alternating optimization strategy, and we provide theoretical evidence of its scalability with linear computational complexity. Furthermore, an out-of-sample extension of AMKSC based on multiview collaborative representation-based classification is introduced, enabling the handling of larger datasets and unseen instances. Extensive experiments on three real heterogeneous RS datasets confirm the superiority of our proposed approach over state-of-the-art methods in terms of clustering performance and time efficiency. The source code is available at https://github.com/AngryCai/AMKSC.

A neurofunctional signature of subjective disgust generalizes to oral distaste and socio-moral contexts.

While disgust originates in the hard-wired mammalian distaste response, the conscious experience of disgust in humans strongly depends on subjective appraisal and may even extend to socio-moral contexts. Here, in a series of studies, we combined functional magnetic resonance imaging with machine-learning-based predictive modelling to establish a comprehensive neurobiological model of subjective disgust. The developed neurofunctional signature accurately predicted momentary self-reported subjective disgust across discovery (n = 78) and pre-registered validation (n = 30) cohorts and generalized across core disgust (n = 34 and n = 26), gustatory distaste (n = 30) and socio-moral (unfair offers; n = 43) contexts. Disgust experience was encoded in distributed cortical and subcortical systems, and exhibited distinct and shared neural representations with subjective fear or negative affect in interoceptive-emotional awareness and conscious appraisal systems, while the signatures most accurately predicted the respective target experience. We provide an accurate functional magnetic resonance imaging signature for disgust with a high potential to resolve ongoing evolutionary debates.

Surface-displayed phenolic acid decarboxylase for increased vinylphenolic pyranoanthocyanins in blueberry wine.

During the fruit wine production, phenolic acid decarboxylase (PAD) converts free hydroxycinnamic acid into 4-vinyl derivatives that can then react spontaneously with anthocyanins, generating more stable pyranoanthocyanins that are responsible for the color stability of fruit wine. Nevertheless, the low PAD activity in yeast under the winemaking conditions has largely limited the generation of 4-vinyl derivatives. To bridge this gap, we expressed PAD from Bacillus amyloliquefaciens in Pichia pastoris and surface-displayed it on Saccharomyces cerevisiae. As a result, S. cerevisiae surface-displayed PAD (SDPAD) exhibited an enhanced thermal stability and tolerance to acidic conditions. Fermentation experiments showed that SDPAD can significantly increase the content of vinylphenolic pyranoanthocyanins and thus maintain the color stability of blueberry wine. Our study demonstrated the feasibility of surface display technology for color stability enhancement during the production of blueberry wine, providing a new and effective solution to increase the content of vinylphenolic pyranoanthocyanins in the fruit-based wines.

TET2 Is Downregulated in Early Esophageal Squamous Cell Carcinoma and Promotes Esophageal Squamous Cell Malignant Behaviors.

OBJECTIVE: To explore the expression of the ten eleven translocation (TET) 2 protein in early esophageal squamous cell carcinoma (EESCC), precancerous lesions, and cell lines and to evaluate the effect of TET2 on the functional behavior of EC109 esophageal cancer cells. METHODS: Thirty-one samples of EESCC and precancerous lesions collected via endoscopic submucosal dissection at Taihe Hospital, Shiyan, from February 1, 2017, to February 1, 2019, were analyzed. The study involved evaluating TET2 expression levels in lesion tissue and adjacent normal epithelium, correlating these with clinical pathological features. Techniques including 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide, cell scratch assays, flow cytometry for propidium iodide (PI) staining, Hoechst 333258/PI double staining, and nude mouse tumorigenesis experiments were employed to assess the effect of TET2 on the proliferation, migration, cell cycle, apoptosis, and tumorigenic ability of esophageal cancer cells. RESULTS: TET2 expression was notably reduced in early esophageal cancer tissue and correlated with tumor invasion depth (P < 0.05). Overexpression of TET2 enhanced the proliferation and migration of esophageal cancer cells, increased the cell population in the G0 phase, decreased it in the S phase, and intensified cell necrosis (P < 0.05). There was a partial increase in tumorigenic ability (P = 0.087). CONCLUSION: TET2 downregulation in ESCC potentially influences the necrosis, cell cycle, and tumorigenic ability of esophageal cancer cells, suggesting a role in the onset and progression of esophageal cancer.

Extramedullary infiltration in pediatric acute myeloid leukemia: Results from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) initiative.

BACKGROUND: The outcome of extramedullary infiltration (EMI) in pediatric acute myeloid leukemia (AML) is controversial, and little is known about the implications of stem cell transplantation (SCT) and gemtuzumab ozogamicin (GO) treatment on patients with EMI. METHODS: We retrieved the clinical data of 713 pediatric patients with AML from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) dataset, and analyzed the clinical and prognostic characteristics of patients with EMI at diagnosis and relapse. RESULTS: A total of 123 patients were identified to have EMI at diagnosis and 64 presented with EMI at relapse. The presence of EMI was associated with age ≤2 years, M5 morphology, abnormal karyotype, and KMT2A rearrangements. Hyperleukocytosis and complex karyotype were more prevalent in patients with EMI at relapse. Additionally, patients with EMI at diagnosis had a reduced incidence of FLT3 ITD-/NPM1+, whereas those with EMI at relapse displayed a lower frequency of FLT3 ITD+. Patients with EMI at diagnosis exhibited a lower complete remission (CR) rate at the end of Induction Course 1 and higher relapse incidence. Importantly, EMI at diagnosis independently predicted both shorter event-free survival (EFS) and overall survival (OS). Regarding relapse patients, the occurrence of EMI at relapse showed no impact on OS. However, relapse patients with myeloid sarcoma (MS)/no central nervous system (CNS) exhibited poorer OS compared to those with CNS/no MS. Furthermore, regarding patients with EMI at diagnosis, SCT failed to improve the survival, whereas GO treatment potentially enhanced OS. CONCLUSION: EMI at diagnosis is an independent adverse prognostic risk factor for pediatric AML, and GO treatment potentially improves survival for patients with EMI at diagnosis.

The relationship between social support and professional identity of health professional students from a two-way social support theory perspective: chain mediating effects of achievement motivation and meaning in life.

BACKGROUND: Studies has suggested that receiving social support improves the professional identity of health professional students. According to the two-way social support theory, social support includes receiving social support and giving social support. However, the effect of the two-way social support on health professional students' professional identity has not been clarified yet. METHODS: To explore the mechanism of how two-way social support affects health professional students' professional identity, an observational, cross-sectional study was conducted among a convenience and cluster sample of 1449 health professional students from two medical schools in western China. Measures included a short version of the two-way social support scale, a health professional students' professional identity questionnaire, an achievement motivation scale, and a meaning in life scale. Data were analyzed by use of SPSS26.0 software and PROCESSv4.0 plug-in. RESULTS: Receiving social support, giving social support, achievement motivation, meaning in life, and professional identity were positively correlated with each other. Receiving and giving social support not only directly predicted health professional students' professional identity, but also indirectly predicted health professional students' professional identity through the mediating roles of achievement motivation and meaning in life, and the chain mediating roles of achievement motivation and meaning in life, respectively. The effectiveness of predicting health professional students' professional identity varied among different types of two-way social support, which could be depicted as two-way social support > mainly giving social support > mainly receiving social support > low two-way social support. CONCLUSION: In the medical education, the awareness and ability of health professional students to receive and give social support should be strengthened. More attention should be drawn on the chain mediating effect of achievement motivation and meaning in life between two-way social support and professional identity. The current results shed new light on exploring effective ways of improving health professional students' professional identity, which suggested that more attention should be paid to the positive effects of mainly giving social support and two-way social support rather than only on the effects of receiving social support.

Molecular characterization, expression and antibacterial function of a macin, HdMac, from Haliotis discus hannai.

Macins are a family of antimicrobial peptides, which play multiple roles in the elimination of invading pathogens. In the present study, a macin was cloned and characterized from Pacific abalone Haliotis discus hannai (Designated as HdMac). Analysis of the conserved domain suggested that HdMac was a new member of the macin family. In non-stimulated abalones, HdMac transcripts were constitutively expressed in all five tested tissues, especially in hemocytes. After Vibrio harveyi stimulation, the expression of HdMac mRNA in hemocytes was significantly up-regulated at 12 hr (P < 0.01). RNAi-mediated knockdown of HdMac transcripts affected the survival rates of abalone against V. harveyi. Moreover, recombinant protein of HdMac (rHdMac) exhibited high antibacterial activities against invading bacteria, especially for Vibrio anguillarum. In addition, rHdMac possessed binding activities towards glucan, lipopolysaccharides (LPS), and peptidoglycan (PGN), but not chitin in vitro. Membrane integrity analysis revealed that rHdMac could increase the membrane permeability of bacteria. Meanwhile, both the phagocytosis and chemotaxis ability of hemocytes could be significantly enhanced by rHdMac. Overall, the results showed that HdMac could function as a versatile molecule involved in immune responses of H. discus hannai.

Effect of fasting plasma glucose level in severe fever and thrombocytopenia syndrome patients without diabetes.

Hyperglycemia is correlated with worse in-hospital outcomes in acute infectious diseases such as coronavirus disease 2019 (COVID-19) and severe fever with thrombocytopenia syndrome (SFTS). This study assessed the relationship between fasting plasma glucose (FPG) levels and in-hospital mortality, disease type, and secondary infections among individuals with SFTS without preexisting diabetes. The clinical data and laboratory results upon admission of 560 patients with SFTS without preexisting diabetes meeting the inclusion criteria at Wuhan Union Hospital were collected. FPG levels in surviving patients with SFTS subjects were significantly lower than those in patients with SFTS who had died (P<0.0001). In multivariate Cox regression, high FPG level (≥11.1 mmol/L) was a risk factor independently associated with the in-hospital death of patients with SFTS without preexisting diabetes. Similarly, the FPG levels in general patients with SFTS were significantly lower than those in patients with severe SFTS (P<0.0001). Multivariate logistic regression identified high FPG level (7.0-11.1 mmol/L) as a risk factor independently associated with SFTS severity. While FPG levels were comparable between patients with SFTS with and without secondary infection (P = 0.5521), logistic regression analysis revealed that high FPG levels were not a risk factor for secondary infection in patients with SFTS without preexisting diabetes. High FPG level on admission was an independent predictor of in-hospital death and severe disease in individuals with SFTS without preexisting diabetes. FPG screening upon admission and glycemic control are effective methods for improving the prognosis of patients with SFTS.

The horizontal ladder test (HLT) protocol: a novel, optimized, and reliable means of assessing motor coordination in Sus scrofa domesticus.

Pigs can be an important model for preclinical biological research, including neurological diseases such as Alcohol Use Disorder. Such research often involves longitudinal assessment of changes in motor coordination as the disease or disorder progresses. Current motor coordination tests in pigs are derived from behavioral assessments in rodents and lack critical aspects of face and construct validity. While such tests may permit for the comparison of experimental results to rodents, a lack of validation studies of such tests in the pig itself may preclude the drawing of meaningful conclusions. To address this knowledge gap, an apparatus modeled after a horizontally placed ladder and where the height of the rungs could be adjusted was developed. The protocol that was employed within the apparatus mimicked the walk and turn test of the human standardized field sobriety test. Here, five Sinclair miniature pigs were trained to cross the horizontally placed ladder, starting at a rung height of six inches and decreasing to three inches in one-inch increments. It was demonstrated that pigs can reliably learn to cross the ladder, with few errors, under baseline/unimpaired conditions. These animals were then involved in a voluntary consumption of ethanol study where animals were longitudinally evaluated for motor coordination changes at baseline, 2.5, 5, 7.5, and 10% ethanol concentrations subsequently to consuming ethanol. Consistent with our predictions, relative to baseline performance, motor incoordination increased as voluntary consumption of escalating concentrations of ethanol increased. Together these data highlight that the horizontal ladder test (HLT) test protocol is a novel, optimized and reliable test for evaluating motor coordination as well as changes in motor coordination in pigs.

Passivation strategies for enhancing sensitivity and repeatability of microelectrode electrochemical sensors.

The sensitivity and repeatability are crucial for the practical application of electrochemical sensors. Many studies have focused on sensing materials and electrode structure to enhance sensitivity and repeatability rather than insulating layers. In this paper, polyaniline (PANI) microelectrode arrays were prepared to explore the influence of the insulating layer on sensitivity and repeatability of electrochemical sensors. The effects of different types of insulating layers, the sizes of the electrodes, and the thicknesses of the insulating layers were studied by experiment and simulation. The research findings indicated that the kind of organic insulating layers (Polyimide (PI) and SU-8) did not have a significant effect on the performance of the sensors. However, as the electrode area increased, the PANI film deposited on the electrode exhibited improved uniformity and density, leading to significant improvements in sensitivity and repeatability of the sensors. Additionally, the thickness of the insulating layer also had a significant impact on the performance of the device. The microelectrode with thinner insulating layers exhibited improved performance in sensitivity, repeatability and signal-to-noise ratio. The research findings indicated that increasing the electrode size and reducing the thickness of the insulating layer led to a more uniform and dense PANI film, resulting in an array electrode that exhibits excellent performance and remarkable repeatability.

Dominance by cyanobacteria in the newly formed biofilms on stone monuments under a protective shade at the Beishiku Temple in China.

Following the installation of a protective shade, rapid propagation of microorganisms showing in black and grey colors occurred at Beishiku Temple in Gansu Province of China. This study employed a combination of high-throughput sequencing technology, morphological examinations, and an assessment of the surrounding environmental condition to analyze newly formed microbial disease spots. The investigation unveiled the responsible microorganisms and the instigating factors of the microbial outbreak that subsequently to the erection of the shade. Through comparison of bioinformatics, the ASV method surpasses the OTU method in characterizing community compositional changes by the dominant microbial groups, the phylum Cyanobacteria emerged as the most dominant ones in the microbial community accountable for the post-shade microbial deterioration. The black spot and grey spot are predominantly composed of Mastigocladopsis and Scytonema, respectively. Validation analysis, based on the active RNA-level community results, supported and validated these conclusions. Comparative scrutiny of the microbial community before shade installation and the background environmental data disclosed that the erection of the shade prompted a decrease in temperatures and an increase in humidity within the protected area. Consequently, this spurred the exponential proliferation of indigenous cyanobacteria in the spots observed. The outcomes of this study carry considerable significance in devising preventive conservation strategies for cultural heritage and in managing the process of biodeterioration.

Effectiveness of PD1/PD-L1 combined with anti-angiogenic drugs in patients with advanced nonsmall cell lung cancer: A systematic review and meta-analysis.

Background: Protein-1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1) therapy have become an important treatment approach for patients with advanced nonsmall cell lung cancer (NSCLC), but primary or secondary resistance remains a challenge for some patients. PD-1/PD-L1 combined with anti-angiogenic drugs (AAs) in NSCLC patients have potential synergistic effects, and the survival benefit may vary based on a treatment order. To investigate the efficacy of PD-1/PD-L1 combined with AAs as the treatment for patients with advanced NSCLC. Materials and Methods: We comprehensively searched EMBASE, PubMed, Web of Science, CNKI, VIP, and Wanfang databases from January 2017 to September 2022. The Cochrane risk bias tool evaluated the quality of included randomized clinical trials. Newcastle-Ottawa-Scale score was used to evaluate the quality of retrospective studies. Publication bias was evaluated by funnel plot, Begg's test, and Egger's test. Results: Seventeen articles were finally selected, involving 5182 patients. Meta-analysis results showed that PD1/PD-L1 combined with AAs therapy significantly improved progression-free survival (PFS) (hazard ratio [HR] = 0.61, 95% confidence interval [CI]: 0.50-0.75, P < 0.00001), overall survival (OS) (HR = 0.79, 95% CI: 0.71-0.88, P < 0.00001), and objective response rate (ORR) (risk ratio = 0.88, 95% CI: 0.81-0.96, P = 0.004), with the statistically significant difference. The sensitivity analysis demonstrated the robustness of the PFS, ORR, and OS. Conclusion: The combination of PD-1/PD-L1 inhibitors with AAs in treating advanced patients has exhibited notable therapeutic advantages when contrasted with monotherapy. Specifically, the administration of PD-1/PD-L1 inhibitors in conjunction with AAs, or sequential treatment involving PD-1/PD-L1 followed by AAs, has shown enhanced therapeutic efficacy in this patient population.

Functionalized lignin nanoparticles assembled with MXene reinforced polypropylene with favorable UV-aging resistance, electromagnetic shielding effects and superior fire-safety.

Deterioration in mechanical performances and aging resistance due to the introduction of flame retardants is a major obstacle for bio-based fire-safety polypropylene (PP). Herein, we reported a kind of functionalized lignin nanoparticles assembled with MXene (MX@LNP), and applied it to construct the flame-retardant PP composites (PP-MA) with superior fire safety, excellent mechanical performance, electromagnetic shielding effects and aging resistance. Specifically, the PP-MA doped with only 18 wt% flame-retardant additives (PP-MA18) achieved the UL-94 V-0 rating. In comparison to pure PP, PP-MA18 presented a greatly decreased peak of heat release rate (pHRR), total heat rate (THR), and peak smoke production rate (pSPR) by 79.7 %, 69.0 % and 75.8 %, respectively, and satisfactory decrease in total flammable and toxic volatiles evolved. The formed fine solid microstructure of carbon residuals effectively promoted the compactness of char layers. More importantly, the nano-effect and the strong interface interaction between the complexed MX@LNP and PP enhanced the tensile strength (45.78 MPa) and elongation at break (725.95 %) of PP-MA. Additionally, the significant ultraviolet absorption and electromagnetic wave dissipation performance of MXene and lignin enabled excellent aging resistance and electromagnetic shielding effects of PP-MA compared with PP. This achieved MX@LNP afforded a novel approach for developing flame retardant materials with excellent application performance.

Preferential deposition of buoyant small microplastics in surface sediments of the Three Gorges Reservoir, China: Insights from biomineralization.

Sediments act as sinks of microplastics (MPs) derived from terrestrial ecosystems. However, the fate and transport of MPs at the zone of sediment-overlying water in reservoir environment are poorly understood. Here, the MPs distribution patterns in surface sediments of the Three Gorges Reservoir (TGR) and dominant mechanisms responsible for the sinking of MPs at the zone of sediment-overlying water were comprehensively investigated. The predominant occurrence of small microplastics (<300 µm, SMPs) in surface sediments of the TGR was found, with buoyant polyethene (PE) was dominant polymer types. Interestingly, the high abundance of SMPs in sediments correlated well with the Ca2+/Mg2+ in overlying water, suggesting that divalent cations in overlying water may enhance the preferential deposition of SMPs. Simulation sinking experiments under the presence of Microcystis aeruginosa and two divalent cations using different-sized PE MPs demonstrated that the greater deposition of SMPs was mainly the result of the formation of biogenic calcite on the surface of MPs rather than magnesium minerals, which provides stronger ballasting effects for SMPs than for large MPs. This study first highlights that the impact of biomineralization on preferential sinking of SMPs and enhances the understanding of the transport behaviour of MPs in aquatic environment.

Blockage of mechanosensitive Piezo1 channel alleviates the severity of experimental malaria-associated acute lung injury.

BACKGROUND: Malaria-associated acute lung injury (MA-ALI) is a well-recognized clinical complication of severe, complicated malaria that is partly driven by sequestrations of infected red blood cells (iRBCs) on lung postcapillary induced impaired blood flow. In earlier studies the mechanosensitive Piezo1 channel emerged as a regulator of mechanical stimuli, but the function and underlying mechanism of Piezo1 impacting MA-ALI severity via sensing the impaired pulmonary blood flow are still not fully elucidated. Thus, the present study aimed to explore the role of Piezo1 in the severity of murine MA-ALI. METHODS: Here, we utilized a widely accepted murine model of MA-ALI using C57BL/6 mice with Plasmodium berghei ANKA infection and then added a Piezo1 inhibitor (GsMTx4) to the model. The iRBC-stimulated Raw264.7 macrophages in vitro were also targeted with GsMTx4 to further explore the potential mechanism. RESULTS: Our data showed an elevation in the expression of Piezo1 and number of Piezo1+-CD68+ macrophages in lung tissues of the experimental MA-ALI mice. Compared to the infected control mice, the blockage of Piezo1 with GsMTx4 dramatically improved the survival rate but decreased body weight loss, peripheral blood parasitemia/lung parasite burden, experimental cerebral malaria incidence, total protein concentrations in bronchoalveolar lavage fluid, lung wet/dry weight ratio, vascular leakage, pathological damage, apoptosis and number of CD68+ and CD86+ macrophages in lung tissues. This was accompanied by a dramatic increase in the number of CD206+ macrophages (M2-like subtype), upregulation of anti-inflammatory cytokines (e.g. IL-4 and IL-10) and downregulation of pro-inflammatory cytokines (e.g. TNF-α and IL-1ß). In addition, GsMTx4 treatment remarkably decreased pulmonary intracellular iron accumulation, protein level of 4-HNE (an activator of ferroptosis) and the number of CD68+-Piezo1+ and CD68+-4-HNE+ macrophages but significantly increased protein levels of GPX4 (an inhibitor of ferroptosis) in experimental MA-ALI mice. Similarly, in vitro study showed that the administration of GsMTx4 led to a remarkable elevation in the mRNA levels of CD206, IL-4, IL-10 and GPX-4 but to a substantial decline in CD86, TNF-α, IL-1ß and 4-HNE in the iRBC-stimulated Raw264.7 cells. CONCLUSIONS: Our findings indicated that blockage of Piezo1 with GsMTx4 alleviated the severity of experimental MA-ALI in mice partly by triggering pulmonary macrophage M2 polarization and subsequent anti-inflammatory responses but inhibited apoptosis and ferroptosis in lung tissue. Our data suggested that targeting Piezo1 in macrophages could be a promising therapeutic strategy for treating MA-ALI.

Short-term exposure to extreme temperature and outpatient visits for respiratory diseases among children in the northern city of China: a time-series study.

BACKGROUND: Although studies have indicated that extreme temperature is strongly associated with respiratory diseases, there is a dearth of studies focused on children, especially in China. We aimed to explore the association between extreme temperature and children's outpatient visits for respiratory diseases and seasonal modification effects in Harbin, China. METHODS: A distributed lag nonlinear model (DLNM) was used to explore the effect of extreme temperature on daily outpatient visits for respiratory diseases among children, as well as lag effects and seasonal modification effects. RESULTS: Extremely low temperatures were defined as the 1st percentile and 2.5th percentile of temperature. Extremely high temperatures were defined as the 97.5th percentile and 99th percentile of temperature. At extremely high temperatures, both 26 °C (97.5th) and 27 °C (99th) showed adverse effects at lag 0-6 days, with relative risks (RRs) of 1.34 [95% confidence interval (CI): 1.21-1.48] and 1.38 (95% CI: 1.24-1.53), respectively. However, at extremely low temperatures, both - 26 °C (1st) and - 23 °C (2.5th) showed protective effects on children's outpatient visits for respiratory diseases at lag 0-10 days, with RRs of 0.86 (95% CI: 0.76-0.97) and 0.85 (95% CI: 0.75-0.95), respectively. We also found seasonal modification effects, with the association being stronger in the warm season than in the cold season at extremely high temperatures. CONCLUSIONS: Our study indicated that extremely hot temperatures increase the risk of children's outpatient visits for respiratory diseases. Efforts to reduce the exposure of children to extremely high temperatures could potentially alleviate the burden of pediatric respiratory diseases, especially during the warm season.