Phosphatidic acid-regulated SOS2 controls sodium and potassium homeostasis in Arabidopsis under salt stress.

The maintenance of sodium/potassium (Na+ /K+ ) homeostasis in plant cells is essential for salt tolerance. Plants export excess Na+ out of cells mainly through the Salt Overly Sensitive (SOS) pathway, activated by a calcium signal; however, it is unknown whether other signals regulate the SOS pathway and how K+ uptake is regulated under salt stress. Phosphatidic acid (PA) is emerging as a lipid signaling molecule that modulates cellular processes in development and the response to stimuli. Here, we show that PA binds to the residue Lys57 in SOS2, a core member of the SOS pathway, under salt stress, promoting the activity and plasma membrane localization of SOS2, which activates the Na+ /H+ antiporter SOS1 to promote the Na+ efflux. In addition, we reveal that PA promotes the phosphorylation of SOS3-like calcium-binding protein 8 (SCaBP8) by SOS2 under salt stress, which attenuates the SCaBP8-mediated inhibition of Arabidopsis K+ transporter 1 (AKT1), an inward-rectifying K+ channel. These findings suggest that PA regulates the SOS pathway and AKT1 activity under salt stress, promoting Na+ efflux and K+ influx to maintain Na+ /K+ homeostasis.

Rice potassium transporter OsHAK18 mediates phloem K+ loading and redistribution.

High-affinity K+ transporters/K+ uptake permeases/K+ transporters (HAK/KUP/KT) are important pathways mediating K+ transport across cell membranes, which function in maintaining K+ homeostasis during plant growth and stress response. An increasing number of studies have shown that HAK/KUP/KT transporters play crucial roles in root K+ uptake and root-to-shoot translocation. However, whether HAK/KUP/KT transporters also function in phloem K+ translocation remain unclear. In this study, we revealed that a phloem-localized rice HAK/KUP/KT transporter, OsHAK18, mediated cell K+ uptake when expressed in yeast, Escherichia coli and Arabidopsis. It was localized at the plasma membrane. Disruption of OsHAK18 rendered rice seedlings insensitive to low-K+ (LK) stress. After LK stress, some WT leaves showed severe wilting and chlorosis, whereas the corresponding leaves of oshak18 mutant lines (a Tos17 insertion line and two CRISPR lines) remained green and unwilted. Compared with WT, the oshak18 mutants accumulated more K+ in shoots but less K+ in roots after LK stress, leading to a higher shoot/root ratio of K+ per plant. Disruption of OsHAK18 does not affect root K+ uptake and K+ level in xylem sap, but it significantly decreases phloem K+ concentration and inhibits root-to-shoot-to-root K+ (Rb+ ) translocation in split-root assay. These results reveal that OsHAK18 mediates phloem K+ loading and redistribution, whose disruption is in favor of shoot K+ retention under LK stress. Our findings expand the understanding of HAK/KUP/KT transporters' functions and provide a promising strategy for improving rice tolerance to K+ deficiency.

A 14-3-3 protein positively regulates rice salt tolerance by stabilizing phospholipase C1.

The phosphatidylinositol-specific phospholipase Cs (PI-PLCs) catalyze the hydrolysis of phosphatidylinositols, which play crucial roles in signaling transduction during plant development and stress response. However, the regulation of PI-PLC is still poorly understood. A previous study showed that a rice PI-PLC, OsPLC1, was essential to rice salt tolerance. Here, we identified a 14-3-3 protein, OsGF14b, as an interaction partner of OsPLC1. Similar to OsPLC1, OsGF14b also positively regulates rice salt tolerance, and their interaction can be promoted by NaCl stress. OsGF14b also positively regulated the hydrolysis activity of OsPLC1, and is essential to NaCl-induced activation of rice PI-PLCs. We further discovered that OsPLC1 was degraded via ubiquitin-proteasome pathway, and OsGF14b could inhibit the ubiquitination of OsPLC1 to protect OsPLC1 from degradation. Under salt stress, the OsPLC1 protein level in osgf14b was lower than the corresponding value of WT, whereas overexpression of OsGF14b results in a significant increase of OsPLC1 stability. Taken together, we propose that OsGF14b can interact with OsPLC1 and promote its activity and stability, thereby improving rice salt tolerance. This study provides novel insights into the important roles of 14-3-3 proteins in regulating protein stability and function in response to salt stress.

The Role of Follicular Regulatory T Cells/Follicular Helper T Cells in Primary Immune Thrombocytopenia.

INTRODUCTION: Immune thrombocytopenia (ITP) is an autoimmune disease characterized by thrombocytopenia. Herein, we sought to identify potential immune-related therapeutic targets in ITP. METHODS: The differentially expressed genes (DEGs) between ITP patients and controls in GSE43177 and PRJNA299534 were analyzed. The intersections of the two DEG groups were screened as common genes, and enrichment analysis was performed. Additionally, differential analysis of immune cell levels between ITP and controls was performed. Changes in the proportions of T follicular helper (Tfh) and follicular regulatory T (Tfr) cells in peripheral blood samples from ITP patients, ITP patients responding to therapy, and healthy controls were identified. The expression changes in B-cell lymphoma (Bcl)-6 and interleukin (IL)-21 were further evaluated. RESULTS: A total of 76 common genes were identified, and enrichment analysis found that these genes were mainly associated with neutrophil-mediated immunity, the MAPK signaling pathway, and the FOXO signaling pathway. Furthermore, we found different levels of Tfh cells in patients with ITP and controls. The level of Tfh cells in the peripheral blood is significantly increased in ITP patients and declines after responding to therapy. The Tfr/Tfh ratio was reduced in ITP patients and increased after responding to therapy. IL-21 and Bcl-6 were more highly expressed in ITP patients than in controls. CONCLUSION: We identified abnormally expressed genes in ITP related to immune-related biological functions. We further identified the changes in Tfh and Tfr cells during ITP treatment. This provides a rationale for immunotherapy in ITP patients.

A Live-Attenuated Zika Virus Vaccine with High Production Capacity Confers Effective Protection in Neonatal Mice.

Zika virus (ZIKV) infection during pregnancy has been linked to congenital abnormalities, such as microcephaly in infants. An efficacious vaccine is desirable for preventing the potential recurrence of ZIKV epidemic. Here, we report the generation of an attenuated ZIKV (rGZ02a) that has sharply decreased virulence in mice but grows to high titers in Vero cells, a widely approved cell line for manufacturing human vaccines. Compared to the wild-type ZIKV (GZ02) and a plasmid-launched rGZ02p, rGZ02a has 3 unique amino acid alterations in the envelope (E, S304F), nonstructural protein 1 (NS1, R103K), and NS5 (W637R). rGZ02a is more sensitive to type I interferon than GZ02 and rGZ02p, and causes no severe neurological disorders in either wild-type neonatal C57BL/6 mice or type I interferon receptor knockout (Ifnar1-/-) C57BL/6 mice. Immunization with rGZ02a elicits robust inhibitory antibody responses with a certain long-term durability. Neonates born to the immunized dams are effectively protected against ZIKV-caused neurological disorders and brain damage. rGZ02a as a booster vaccine greatly improves the protective immunity primed by Ad2-prME, an adenovirus-vectored vaccine expressing ZIKV prM and E proteins. Our results illustrate that rGZ02a-induced maternal immunity can be transferred to the neonates and confer effective protection. Hence, rGZ02a may be developed as an alternative live-attenuated vaccine and warrants further evaluation. IMPORTANCE Zika virus (ZIKV), a mosquito-borne flavivirus that has caused global outbreaks since 2013, is associated with severe neurological disorders, such as Guillian-Barré syndrome in adults and microcephaly in infants. The ZIKV epidemic has gradually subsided, but a safe and effective vaccine is still desirable to prevent its potential recurrence, especially in countries of endemicity with competent mosquito vectors. Here, we describe a novel live-attenuated ZIKV, rGZ02a, that carries 3 unique amino acid alterations compared to the wild-type GZ02 and a plasmid-launched rGZ02p. The growth capacity of rGZ02a is comparable to GZ02 in Vero cells, but the pathogenicity is significantly attenuated in two mice models. Immunization with rGZ02a elicits robust inhibitory antibody responses in the dams and effectively protects their offspring against ZIKV disease. Importantly, in a heterologous prime-boost regimen, rGZ02a effectively boosts the protective immunity primed by an adenovirus-vectored vaccine. Thus, rGZ02a is a promising candidate for a live-attenuated ZIKV vaccine.

Ligand-Assisted Controllable Growth of Self-Supporting Ultrathin Two-Dimensional Metal-Organic Framework Nanosheet Electrodes for an Efficient Oxygen Evolution Reaction.

Rational design of metal-organic frameworks (MOFs) into ultrathin two-dimensional (2D) nanosheets with controllable thickness is significantly attractive but is also a significant challenge. Herein, the authors report, for the first time, the synthesis of ultrathin 2D nickel-based MOF nanosheets with a thickness of only about 2 nm via a ligand-assisted controllable growth strategy, which cannot be acquired from the exfoliation of their bulky counterparts or the conventional hydrothermal method. The correlation between 2D nanosheets and crystal growth preference was demonstrated through a judicious choice of a specific [Ni(BIP)(p-BDC)(H2O)2]n framework (BIP = (3,5-bis(1-imidazoly)pyridine), p-H2BDC = terephthalic acid) to underlie the geometry of the resultant morphology. Under the modulation by the dosage of terephthalic acid through a corrosion-dissolution-coordination process, the nanosheets of Ni-MOFs with a controllable thickness can be tuned to 50 and 100 nm. Ultrathin 2D Ni-MOF nanosheet-derived N-doped Ni@carbon exhibits a satisfactory electrocatalytic performance with a small overpotential of 170 mV to achieve a current density of 10 mA cm-2, much outperforming the bulk Ni-MOF and the most reported non-noble-metal oxygen evolution reaction electrocatalysts to date. It is believed that this ligand-assisted controllable growth strategy represents a novel and simple path to prepare high-performance MOF-based electrocatalysts for wide applications.

Evidence and Mass Quantification of Atmospheric Microplastics in a Coastal New Zealand City.

This study investigated the atmospheric deposition of microplastics (MPs) in Auckland, New Zealand, from two sampling sites over a 9-week period. The sizes, morphologies, number counts, and mass concentrations of specific polymers were determined for airborne MPs using a combination of a Nile Red-assisted automated fluorescence microscopy technique in series with pyrolysis-gas chromatography-mass spectrometry (Pyr-GC/MS). This enabled a larger number of MPs to be analyzed from each sample compared to traditional spectroscopic techniques. Microplastic number concentrations increased exponentially with decreasing size. The results show the importance of using consistent methodologies and size cutoffs when comparing microplastic data between studies. Eight polymers were quantified in the atmospheric deposition samples, with polyethylene (PE), polycarbonate (PC), and poly(ethylene terephthalate) (PET) being the most commonly observed. The largest MP deposition rates at an urban rooftop correlated with winds originating from the marine environment with speeds between 15 and 20 m s-1, indicating that airborne MPs in coastal regions may originate from wave-breaking mechanisms. This study represents the first report of using Pyr-GC/MS to determine the chemical compositions and mass concentrations of atmospheric microplastics, along with corresponding data on their sizes, morphologies, and number counts.

Toxicological evaluation of S. involucrata culture: Acute, 90-day subchronic and genotoxicity studies.

Saussurea involucrata is an endangered plant that is used in traditional Chinese medicine. Through the use of plant cell culture techniques, preparations of Saussurea involucrata (S. involucrata) cell cultures have been developed and used to generate medicinal preparations. There have been few evidence-based analyses of the toxicological effects of S. involucrata culture conducted to date. Here, we conducted the experiments designed to assess the acute, subchronic, and genotoxic toxicological effects of S. involucrata culture. The genotoxic study was assessed through Ames, marrow micronucleus, and sperm malformation assays. The acute toxicity was assessed by orally administering in rats and mice at dose of 7500 mg/kg. Subchronic toxicity studies were then conducted by administering rats at doses of 500, 1000, or 1500 mg/kg for 90 days. No genotoxicity was observed at any tested dose levels, nor was any evidence of acute toxicity detected in treated mice or rats. Similarly, subchronic study of S. involucrata culture administration was not associated with any changes in rat food intake, weight, hematological parameters, organ weight, or organ histology. Then, we determined that the no observed adverse effect level of S. involucrata culture was greater than 1500 mg/kg in our 90-day toxicity study.

[Research progress on culture technologies,chemical components,and pharmacological activities of Saussurea involucrata cells].

Saussurea involucrata,a traditional Chinese medicinal material,is effective in the treatment of rheumatoid arthritis with cold-dampness blockage syndrome,cold pain in lower abdomen,and menstrual irregularities. However,due to the specific habitat,low natural reproduction rate,slow growth,and overexploitation,it is at the high risk of extinction. S. involucrata cells can be obtained through callus culture,suspension culture,and hairy root culture. This study highlighted the influences of reactor type,culture system,precursor,elicitor type, and light wavelength on the suspension culture of S. involucrate cells. The chemical components of S. involucrata cells mainly include phenylpropanoids,flavonoids,lignans,and steroids,among which phenylpropanoids are the most abundant. S. involucrata cells have multiple pharmacological activities of anti-inflammation,analgesia,activating blood and resolving stasis,immunoregulation,increasing bone density,lowering blood lipids,anti-hypoxia,anti-exercise fatigue,anti-radiation,anti-obesity,and anti-oxidation. Moreover,it has the potential of treating aplastic anemia. This study reviews the cell culture technologies,chemical components,and pharmacological activities of S. involucrata cells,laying a basis for the further research,development,and utilization.

Modeling abnormal early development with induced pluripotent stem cells from aneuploid syndromes.

Many human diseases share a developmental origin that manifests during childhood or maturity. Aneuploid syndromes are caused by supernumerary or reduced number of chromosomes and represent an extreme example of developmental disease, as they have devastating consequences before and after birth. Investigating how alterations in gene dosage drive these conditions is relevant because it might help treat some clinical aspects. It may also provide explanations as to how quantitative differences in gene expression determine phenotypic diversity and disease susceptibility among natural populations. Here, we aimed to produce induced pluripotent stem cell (iPSC) lines that can be used to improve our understanding of aneuploid syndromes. We have generated iPSCs from monosomy X [Turner syndrome (TS)], trisomy 8 (Warkany syndrome 2), trisomy 13 (Patau syndrome) and partial trisomy 11;22 (Emanuel syndrome), using either skin fibroblasts from affected individuals or amniocytes from antenatal diagnostic tests. These cell lines stably maintain the karyotype of the donors and behave like embryonic stem cells in all tested assays. TS iPSCs were used for further studies including global gene expression analysis and tissue-specific directed differentiation. Multiple clones displayed lower levels of the pseudoautosomal genes ASMTL and PPP2R3B than the controls. Moreover, they could be transformed into neural-like, hepatocyte-like and heart-like cells, but displayed insufficient up-regulation of the pseudoautosomal placental gene CSF2RA during embryoid body formation. These data support that abnormal organogenesis and early lethality in TS are not caused by a tissue-specific differentiation blockade, but rather involves other abnormalities including impaired placentation.

Investigating the deposition of fibrous zeolite particles on leaf surfaces: A novel low-cost method for detecting the presence of airborne hazardous mineral fibers.

Naturally occurring fibrous minerals, such as erionite, can pose a significant threat to human health when disturbed and subsequently respired. Understanding the spatial abundance and characteristics of these hazardous fibrous minerals in ambient air is crucial for minimizing human exposure and assessing risk. Conventional detection methods for airborne hazardous mineral fibers, such as those developed for asbestos, are of limited utility in environmental settings where fiber concentrations are low and different fiber types may be present and can be costly especially when monitoring large areas over long periods of time. This study presents an innovative methodology for detecting and identifying the presence of airborne naturally occurring fibrous zeolites, using leaf surface deposition sampling, SEM-EDX analysis for the detection and assessment of elemental composition, and TEM-SAED with continuous rotation diffraction (MicroED) to determine their crystallographic unit cell parameters. In total, 309 fibrous zeolite particles (FZPs) were identified on a range of tree leaf surfaces across 80 % of the sampling sites located close to both active and disused zeolite quarries in the Taupo Volcanic Region, New Zealand. The FZPs displayed various morphologies including aggregates, bundles, and fibril-like structures. Of the FZPs detected, 92.2 % were < 5 µm in length. Tetrahedral Si:(Si+Al) ratio results indicated that 40 % of the FZPs were in the reference range for zeolite mordenite. TEM-SAED plus MicroED analysis resulted in 61 % of tested FZPs indexed to unit cell parameters that matched with mordenite. This research demonstrates the potential of leaf sampling as a cost-effective method for detecting airborne FZPs while the MicroED data can be utilized for distinguishing between different types of airborne fibrous zeolites in ambient air.

Comparative study of Fe(II)/sulfite, Fe(II)/PDS and Fe(II)/PMS for p-arsanilic acid treatment: Efficient organic arsenic degradation and contrasting total arsenic removal.

As a widely used feed additives, p-arsanilic acid (p-AsA) frequently detected in the environment poses serious threats to aquatic ecology and water security due to its potential in releasing more toxic inorganic arsenic. In this work, the efficiency of Fe(II)/sulfite, Fe(II)/PDS and Fe(II)/PMS systems in p-AsA degradation and simultaneous arsenic removal was comparatively investigated for the first time. Efficient p-AsA abatement was achieved in theses Fe-based systems, while notable discrepancy in total arsenic removal was observed under identical acidic condition. By using chemical probing method, quenching experiments, isotopically labeled water experiments, p-AsA degradation was ascribed to the combined contribution of high-valent Fe(IV) and SO4•-in these Fe(II)-based system. In particular, the relative contribution of Fe(IV) and SO4•- in the Fe(II)/sulfite system was highly dependent on the molar ratio of [Fe(II)] and [sulfite]. Negligible arsenic removal was observed in the Fe(II)/sulfite and Fe(II)/PDS systems, while ∼80% arsenic was removed in the Fe(II)/PMS system under identical acidic condition. This interesting phenomenon was due to that ferric precipitation only occurred in the Fe(II)/PMS system. As(V) was further removed via adsorption onto the iron precipitate or the formation of ferric arsenate-sulfate compounds, which was confirmed by particle diameter measurements, fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Through tuning solution pH, complete removal of total arsenic could achieve in all three systems. Among these three Fe-based technologies, the hybrid oxidation-coagulation Fe(II)/PMS system demonstrated potential superiority for arsenic immobilization by not requiring pH adjustment for coagulation and facilitating the in-situ generation of ferric arsenate-sulfate compounds with comparably low solubility levels like scorodite. These findings would deepen the understanding of these three Fe-based Fenton-like technologies for decontamination in water treatment.

Hollow Carbon Nanopillar Arrays Encapsulated with Pd-Cu Alloy Nanoparticles for the Oxygen Evolution Reaction.

Delicate design and bottom-up synthesis of hollow nanostructures for oxygen evolution electrocatalysts is a promising way to accelerate the reaction kinetics of overall water splitting. Herein, an efficient and versatile strategy for the controllable preparation of Pd-Cu alloy nanoparticles encapsulated in carbon nanopillar arrays (PD-Cu@HPCN) is developed. Core-shell structured MOF@imidazolium-based ionic polymers (ImIPs) have been prepared and adopted as a template, along with the decomposition of the inner Cu-MOFs when an anion exchange occurs between sodium tetrachloropalladate in solution and bromides in the external ImIP shell. Pd nanoparticles will be highly dispersed in the resulting Pd-Cu@HO-ImIP array, and subsequent topotactic transformation generates Pd-Cu@HNPC. No hazardous reagents or tedious steps are used to remove the inner Cu-MOF templates in contrast to the traditional top-down methods. Remarkably, the Pd-Cu@HPCN catalyst possesses outstanding oxygen evolution reaction (OER) activity, including small overpotential with 10 mA cm-2 at an overpotential of 188 mV, a large double layer capacitance (73.8 mF cm-2), and high stability (20 h). This simple, green, and efficient synthesis methodology represents a new way to design metal alloys for OER electrocatalysts or other electrocatalytic devices.

Relationships of platelet glycoprotein specific antibody with therapeutic efficacy of short-term high-dose dexamethasone and bleeding score in the newly diagnosed adult patients with primary immune thrombocytopenia.

Objectives: We aimed to investigate relationships of platelet glycoprotein (GP) specific antibody with therapeutic efficacy of high-dose dexamethasone (HD-DXM) and bleeding score in primary immune thrombocytopenia (ITP) adults. Methods: A retrospective study was carried out to analyze relationships of polymorphism of GP specific antibody with initial therapeutic efficacy of HD-DXM and bleeding score of newly diagnosed ITP adults between 1 June, 2016 and 31 January, 2020. Results: 59 patients were involved in the study, with 33 cases of responders and 26 cases of non-responders between June 2016 and January 2020. At admission, there were 31 (52.5%) GP antibody-positive patients. Initial therapy of HD-DXM was effective for 78.6% GP antibody-negative patients and 35.5% GP antibody-positive patients, with a better therapeutic efficacy in patients with anti-GP Ib/IX antibody or anti-GP IIb/IIIa antibody but not in those with anti-GP Ib/IX antibody plus anti-GP IIb/IIIa antibody. Notably, therapeutic efficacy is much worse for minority (Uyghur) patients compared with corresponding Han patients. Similarly, it was much lower in GP antibody-positive patients compared with corresponding negative ones at low and medium bleeding score, with no response in GP antibody-positive patients at high bleeding score. Furthermore, there was a moderate negative correlation between therapeutic efficacy and GP-specific antibody (p < 0.05), but no obvious linear relationship between clinical bleeding degree and GP-specific antibody (p > 0.05). Conclusion: Collectively, the newly diagnosed ITP adults with GP-specific antibody have a poor response to short-term HD-DXM, especially in minority (Uyghur) patients with GP-specific antibody in China.

Imbalance of follicular regulatory T (Tfr) cells/follicular helper T (Tfh) cells in adult patients with primary immune thrombocytopenia.

This study is to investigate the role of follicular regulatory T (Tfr) cells/follicular helper T (Tfh) cells imbalance in adult patients with primary immune thrombocytopenia (ITP). Totally, 40 cases of primary ITP patients and 30 healthy controls were enrolled. Blood samples were collected from ITP patients (pre- and post-therapy) and controls. Flow cytometry was used to detect the proportion of Tfr and Tfh cells in peripheral blood. Real-time quantitative polymerase chain reaction (PCR) was performed to detect the mRNA expression levels of FOXP3, BCL-6, and BLIMP-1. Enzyme-linked immunosorbent assay (ELISA) was conducted to detect interleukin (IL)-10 and IL-21 levels. Spearman's correlation was used for correlation analysis. Compared with control, Tfr cell proportion, FOXP3 mRNA, and IL-10 were significantly decreased in the pre-therapy ITP group, but were significantly increased post-therapy. Tfh cell proportion, BCL-6 mRNA, and IL-21 were increased, while BLIMP-1 mRNA was decreased, in the pre-therapy ITP group than the control group. These effects were reversed in the post-therapy ITP group. Moreover, the Tfr/Tfh ratio was decreased in the pre-therapy ITP group than control group, whereas was increased in the post-therapy ITP group than the pre-therapy ITP group. Furthermore, Tfr cell proportion, FOXP3 mRNA, IL-10, and Tfr/Tfh ratio were positively correlated with the platelet count (PLT) in the ITP pre-therapy group. In addition, Tfh cell proportion, BCL-6 mRNA, and IL-21 were negatively correlated with the PLT, while BLIMP-1 mRNA was positively correlated with the PLT. Conclusively, Tfr cell proportion in peripheral blood is decreased and Tfh cell proportion is increased, leading to unbalanced Tfr/Tfh ratio in ITP patients pre-therapy. The imbalance of Tfr/Tfh is recovered post-therapy, suggesting that the Tfr and Tfh cells may be involved in ITP pathogenesis. The abnormal expression of FOXP3, BCL-6, and BLIMP-1 mRNA and the changes in IL-10 and IL-21 levels may be related to the imbalance of Tfr/Tfh.

SARS-CoV-2 induces cardiomyocyte apoptosis and inflammation but can be ameliorated by ACE inhibitor Captopril.

Although the clinical manifestation of COVID-19 is mainly respiratory symptoms, approximately 20% of patients suffer from cardiac complications. COVID-19 patients with cardiovascular disease have higher severity of myocardial injury and poor outcomes. The underlying mechanism of myocardial injury caused by SARS-CoV-2 infection remains unclear. Using a non-transgenic mouse model infected with Beta variant (B.1.351), we found that the viral RNA could be detected in lungs and hearts of infected mice. Pathological analysis showed thinner ventricular wall, disorganized and ruptured myocardial fiber, mild inflammatory infiltration, and mild epicardia or interstitial fibrosis in hearts of infected mice. We also found that SARS-CoV-2 could infect cardiomyocytes and produce infectious progeny viruses in human pluripotent stem cell-derived cardiomyocyte-like cells (hPSC-CMs). SARS-CoV-2 infection caused apoptosis, reduction of mitochondrial integrity and quantity, and cessation of beating in hPSC-CMs. In order to dissect the mechanism of myocardial injury caused by SARS-CoV-2 infection, we employed transcriptome sequencing of hPSC-CMs at different time points after viral infection. Transcriptome analysis showed robust induction of inflammatory cytokines and chemokines, up-regulation of MHC class I molecules, activation of apoptosis signaling and cell cycle arresting. These may cause aggravate inflammation, immune cell infiltration, and cell death. Furthermore, we found that Captopril (hypotensive drugs targeting ACE) treatment could alleviate SARS-CoV-2 induced inflammatory response and apoptosis in cardiomyocytes via inactivating TNF signaling pathways, suggesting Captopril may be beneficial for reducing COVID-19 associated cardiomyopathy. These findings preliminarily explain the molecular mechanism of pathological cardiac injury caused by SARS-CoV-2 infection, providing new perspectives for the discovery of antiviral therapeutics.

Transformation mechanisms of iopamidol by iron/sulfite systems: Involvement of multiple reactive species and efficiency in real water.

Although the ability of iron/sulfite system for decontamination purposes has been investigated, the complex reactive species generated and the underlying transformation mechanisms remain elusive. Here, we have comprehensively examined the transformation of iopamidol (IPM), a representative of iodinated X-ray contrast media, by iron catalyzed sulfite oxidation process under different water chemistry conditions. Multiple reactive intermediates including Fe(IV), SO4•-, and SO5•- were identified by conducting a series of experiments. Eight transformation products were detected by mass spectrometry analysis, and correlation with the nature of involved reactive species has been made. Further, the transformation pathways including amide hydrolysis, deiodination, amino and hydroxyl groups oxidation were proposed. Interestingly, these transformation products could be removed through adsorption to iron precipitates formed via pH adjustment. Combining Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, we revealed an effective way to reduce the amount of transformation products in the treated solutions. Since the iron/sulfite process appears to be less sensitive to natural organic matter, it exhibited very good efficiency for IPM removal in real water samples, even with a high organic carbon loading. These findings may have strong implications in the development of novel oxidation process based on the sulfite/iron systems for wastewater treatment.

Regulation of Th1/Th2 and Th17/Treg by pDC/mDC imbalance in primary immune thrombocytopenia.

This study investigates the regulatory effect of plasmacytoid dendritic cells (pDC)/myeloid dendritic cells (mDC) imbalance on balance of Th1/Th2 and Th17/Treg in primary immune thrombocytopenia (ITP). A total of 30 untreated ITP patients and 20 healthy controls were recruited. Compared with healthy control, the pDC proportion of ITP patients was significantly reduced (P = 0.004), while the mDC proportion was not significantly changed (P = 0.681), resulting in a decrease in the pDC/mDC ratio (P = 0.001). Additionally, compared with controls, serum levels of interleukin (IL)-6, IL-12, and IL-23 were increased in ITP patients (P < 0.001), and mRNA levels of IL-12p40, IL-12p35, and IL-23p19 were also increased (P =0.014, P = 0.043, P < 0.001). Compared with the healthy control, the proportion of Th1 and Th17 cells in ITP patients increased (P = 0.001, P = 0.031). Serum levels of interferon gamma (IFN-γ) and IL-17 in ITP patients also increased (P = 0.025, P = 0.005). Furthermore, T-bet and RORγt mRNA levels were increased in peripheral blood of ITP patients (P = 0.018, P < 0.001). Correspondingly, the proportion of Th2 and Treg cells decreased (P = 0.007, P < 0.001), along with a decrease in serum IL-4 and transforming growth factor beta (TGF-ß) (P = 0.028, P = 0.042), and an increase in GATA-3 mRNA (P < 0.001). However, there was no significant difference in Foxp3 mRNA levels (P = 0.587). Pearson correlation analysis showed that the proportion of total dendritic cells (DCs) was positively correlated with IL-12 (r = 0.526, P = 0.003) and IL-23 (r = 0.501, P = 0.005) in ITP patients. Th1/Th2 ratio, IFN-γ, and IL-12 levels were negatively correlated with platelet counts (r = -0.494, P = 0.009; r = -0.415, P = 0.028; r = -0.492, P = 0.032). However, IL-23 was positively correlated with IL-17 (r = 0.489, P = 0.006) and negatively correlated with platelet count (r = -0.564, P = 0.001). The ratio of IL-6 and Th17 cells was negatively correlated with platelet count (r = -0.443, P = 0.014; r = -0.471, P = 0.011). The imbalance of pDC/mDC and the increase of IL-6, IL-12, and IL-23 lead to the increased differentiation of CD4+ T cells into Th1 and Th17 cells, which might be the important mechanisms underlying the imbalance of Th1/Th2 and Th17/Treg in ITP patients.

Slow-freezing cryopreservation of neural stem cell spheres with different diameters.

Neural stem cells (NSCs) are of great value for clinical application and scientific research. The development of efficient cryopreservation protocols could significantly facilitate the storage and transportation for clinic applications. The objective of the present study is to improve the survival rate and viability of NSCs. Neural stem cells with three states of single-cell suspension, NSC spheres with diameters of 30-50 microm and 80-100 microm, were cryopreserved by slow-freezing method with the cryoprotective agent (CPA) of dimethyl sulfoxide (Me(2)SO), respectively. Then the post-thawing NSCs were tested for the survival rate and the differentiation ability. As a result, NSC spheres with diameter of 80-100 microm and Me(2)SO concentration of 8% achieve the survival rate of 82.9%, and the NSCs still sustain the multi-differentiation potentiality. These results indicated that both the subtle interaction among NSCs and sphere diameters may affect the survival rate together.

[Expression and Significance of Shh Signaling Pathway in Bone Marrow CD34+ Cells of Patients with Myelodysplastic Syndrome and Acute Myeloid Leukemia with Myelodysplasia-Related Changes].

OBJECTIVE: To study the expression of Shh singaling related gene, including Shh, Ptch1, Smo and Gli1 in bone marrow CD34+ cells of patients with myelodysplastic syndrome(MDS) and acute myeloid leukemia with myelodysplasia-related changes(AML-MRC), and to explore their clinical significance. METHODS: The count of CD34+ cells in bone marrow was detected by flow cytometry in 53 patients with MDS and 30 patients with AML-MRC. Magnetic beads were used to separate CD34+ cells. The expression of Shh, Ptch1,Smo and Gli1 on CD34+ cells was detected by qRT-PCR, the effect of the 4 gene expression on prognosis of patients in MDS and AML-MRC group was compared, 25 patients with iron-deficiency anemia were used as controls. RESULTS: The expression levels of Shh, Smo and Gli1 of patients in MDS and AML-MRC group were significantly higher than those in control group (P＜0.05), moreover increased with disease progression(P<0.05). The expression of Ptch1 was not statistically significantly different between 3 groups（P＞0.05）. In comparison of prognosis, the expression of Smo and Gli1 in the patients of relatively high risk groups and AML-MRC groups were significantly increased (P<0.05). The median overall survival time of patients in MDS and AML-MRC groups was 12（7.5，16.5） and 6（3.0，9.0） months (P=0.000) respectively. The median survival time of MDS and AML-MRC patients with high expression of Smo and Gli1 was significantly shorter than that of MDS and AML-MRC patients with low expression of Smo and Gli1(P<0.05). CONCLUSION: Shh signaling pathway in the patients with MDS is activated, which is involved in the progress and prognosis of MDS.