[Mechanism of Alisma orientale in treating nonalcoholic fatty liver disease]

In this study, network pharmacology technology was combined with molecular docking technology and experimental verification to clarify the active ingredients, potential targets and mechanism of Alisma orientale for nonalcoholic fatty liver disease(NAFLD), providing a basis for its clinical application. The active ingredients of A. orientale were screened through traditional Chinese medicine systems pharmacology database(TCMSP), and the potential targets related to both active ingredients and NAFLD were predicted through protein databases by considering the oral bioavailability(OB) and drug-likeness(DL). The "active ingredient-potential target" network was constructed by using Cytoscape software, and the molecular docking was performed between active ingre-dients and potential targets. KEGG pathway analysis and enrichment analysis were performed through DAVID biological information annotation databases. ClueGO software was used to analyze target GO annotation. Western blot and immunocytochemistry were used to detect the protein expression levels, and fluorescent probe was used to detect the reactive oxygen species(ROS) generation level. The results revealed that 7 active ingredients of A. orientale were obtained from TCMSP database and analysis platform, 140 ingredient-related targets were screened, and 59 potential targets were obtained by intersecting disease targets with ingredient-related targets. Molecular docking showed that 7 active ingredients of A. orientale could act on the potential targets including 3-hydroxy-3-methylglutaryl-coenzyme A reductase(HMGCR) and tyrosine-protein phosphatase non-receptor type 1(PTPN1). In addition, KEGG enrichment analysis showed that the potential targets were mainly enriched in inflammatory mediator regulation, insulin resistance, neuroactive ligand-receptor interaction, vascular smooth muscle contraction, FcγR-mediated phagocytosis and other related pathways of tryptophan(TRP) channel. GO enrichment analysis showed that potential targets mainly affected the biological processes of G-protein coupled receptor signaling pathway, organic hydroxyl compound transport, positive regulation of lipid biosynthesis process, positive regulation of lipid metabolic process. Western blot, immunocytochemistry and fluorescent probe confirmed that the extract of A. orientale could reduce HMGCR and PTPN1 protein expression levels effectively, and also could reduce ROS production level of HepG2 cells. This study systematically revealed the material basis and mechanism of A. orientale in regulating NAFLD through multi-component, multi-target, and multi-pathway characteristics, which provided a theoretical basis and scientific basis for the clinical application of A. orientale.

Inhibition of CD44 attenuates pressure overload-induced cardiac and lung inflammation, fibrosis, and heart failure progression

Background

Inflammation contributes to heart failure (HF) development and progression. CD44 is a member of the hyaluronate receptor family of cell adhesion molecules, which regulates tissue inflammation and fibrosis through modulating macrophage and lymphocyte migration and homing in several diseases. Here we evaluated the role and cellular mechanism of CD44 in regulating transverse aortic constriction (TAC)-induced HF development and progression in mice.

Methods and results

C57/B6 background CD44 KO and wild type mice (6–8 weeks) were subjected to TAC to evaluate the effect of CD44 on the development of TAC-induced LV hypertrophy and cardiac dysfunction. Due to the rapid response to TAC, Balb/c mice (6–8 weeks) were used to determine the effect of CD44 on the progression of TAC-induced congestive heart failure. We found that CD44 expression is dramatically increased in left ventricular (LV) tissues obtained from HF patients and mice. While CD44 gene knockout (KO) has no detectable effect on cardiac structure and function under control conditions, CD44 KO mice were protected from TAC-induced LV inflammation, fibrosis, hypertrophy, dysfunction, and lung remodeling as compared with wild type mice. In addition, we found that inhibition of CD44 signaling with blocking antibodies (Abs) significantly attenuated the transition from LV failure to lung remodeling, and right ventricular hypertrophy in mice with existing HF.

Conclusions

These data identify an important role of CD44 in attenuating cardiac and lung inflammation, fibrosis, HF development, and HF progression, suggesting that inhibition of CD44 signaling may be useful in preventing and treating HF.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Chinese National Natural Science Foundation Grants and American Heart Association

Elevated air temperature damage to photosynthetic apparatus alleviated by enhanced cyclic electron flow around photosystem I in tobacco leaves

High temperature can lead to increased production of excess light energy, thus reducing photosynthetic capacity in plants. Photosynthetic cyclic electron flow (CEF) in photosystem I (PSI) can effectively protect photosystems, but its physiological mechanism under high temperature is poorly understood. In this study, antimycin A (AA) and thenoyltrifluoroacetone (TTFA) were used to inhibit PGR5-and NDH-dependent CEF pathways, respectively, to reveal the photoprotective functions of CEF for PSII in tobacco leaves under high temperature stress (37 °C, HT). High temperatures caused decreases in maximal photochemistry efficiency (Fv/Fm) and damaged photosystem II (PSII) in tobacco leaves. Under AA inhibition of PGR5-dependent CEF, high temperature increased the fluorescence intensity of point O (Fo) in OJIP curves, i.e., the energy absorption per active reaction center (ABS/RC), the trapping rate of the reaction center (TRo/RC), and the electron transport efficiency per reaction center (ETo/RC) in tobacco leaves. High temperature induced an increase in the hydrogen peroxide content and a decrease in pigment content in tobacco leaves. Under the high temperature treatment, inhibition of PGR5-dependent CEF reduced the activities of the PSII reaction center significantly, destroyed the oxygen-evolving complex (OEC), and impeded photosynthetic electron transfer from PSII to the plastoquinone (PQ) pool in tobacco leaves. The TTFA treatment inhibited the NDH-dependent pathway under high temperature conditions, with the relative fluorescence intensity of point I (VI) decreased significantly, and the content of hydrogen peroxide and superoxide anion increased significantly. Additionally, Fo and the redox degree of the PSII donor side (Wk) increased, and pigment content decreased compared to the control, but with little change compared to high temperature treatment, indicating that the inhibition of the NDH-dependent pathway directly weakened the capacity of the PQ pool to lead to the accumulation of reactive oxygen species (ROS) in tobacco leaves. In conclusion, CEF alleviated damage to the photosynthetic apparatus in tobacco leaves by increasing PSII heat dissipation, reducing ROS production, and maintaining the stability of the PQ pool to accommodate photosynthetic electron flow.

Abstract 1050: Serum interleukin-27 serves as an early biomarker predicting development of hepatocellular carcinoma (HCC) in two large prospective cohorts

Background: Interleukin-27 (IL-27), which consists of p28 and Epstein-Barr virus induced gene 3 (EBI3) subunits, is a heterodimeric member of the IL-12/IL-23 cytokine family. Overexpression of IL-27 increases T cell expression of inhibitory receptors including PD-1, LAG3, TIGIT, and TIM3 that could limit intensity and duration of T cell responses to infection and cancer. IL-27 is overexpressed in HCC. The purpose of the study was to examine the role of IL-27 in the development of HCC in humans.

Methods: Two parallel studies were conducted. The discovery study included 100 HCC cases and 100 individually matched controls from the Singapore Chinese Health Study, which enrolled 32,000 participants with blood samples free of cancer at entry into the study and subsequently followed up for >15 years. The validation study also included 100 HCC cases and 100 matched controls from the Shanghai Cohort Study, a prospective cohort of 18,000 participants who were free of cancer at entry and similarly followed up for >20 years. Human IL-27 protein was quantified in sera that were collected, on average, 4.5 year prior to the diagnosis of HCC. Conditional logistic regression method was used to estimate odds ratio (OR) and 95% confidence interval (CI) of HCC for higher tertiles of IL-27 with adjustment for hepatitis B surface antigen (HBsAg), alcohol intake, body mass index and cigarette smoking. The Cancer Genome Atlas (TCGA) data were analyzed for the IL-27 gene expression in liver and other cancers.

Results: Serum IL-27 levels were significantly higher in persons who subsequently developed HCC than controls who remained free of HCC in both studies. In the discovery study, persons in the 2nd (1.39-1.95 ng/mL) and 3rd tertile of IL-27 (>1.95 ng/ml) had 9.3 (95% CI = 1.07-80.36) and 51.7 (95% CI = 5.1-527.8) times the risk of developing HCC, respectively, compared with the lowest IL-27 (<1.39 ng/ml). These novel results were confirmed in the validation study; the corresponding ORs (95% CIs) for HCC were 4.9 (1.2-19.6) and 16.3 (3.5-77.4) (both Ptrend < 0.001). When IL-27 and HBsAg were jointly analyzed, the OR (95% CI) of HCC was 24.73 (3.23-189.09) for lowest IL-27 & positive HBsAg, 45.52 (8.71-237.91) for highest IL-27 & negative HBsAg, and 265.19 (40.69-1728.45) for highest IL-27 & positive HBsAg, compared with lowest IL-27 & negative HBsAg. The TCGA analysis revealed that the IL-27 mRNA levels in primary liver cancer was at least 20 times higher than that of any other cancer.

Conclusion: Higher serum levels of IL-27 are associated with significantly higher risk of HCC development.

Implications: IL-27 can be further developed as a biomarker for identification of individuals at high risk for HCC and for diagnosis of HCC at an early stage, enabling more frequent surveillance. Anti-IL-27 agents may be developed for primary prevention of HCC. The blockade of IL-27 alone or in combination with other anti-immunosuppressive agents such as anti-PD1, anti-PD-L1, IL-2 and anti-LAG3 may represent novel immunotherapy strategies for HCC.

Citation Format: Jian-Min Yuan, Wang Yue, Renwei Wang, Jennifer Admas-Haduch, Woon-Puay Koh, Yu-Tang Gao, Michael T. Lotze. Serum interleukin-27 serves as an early biomarker predicting development of hepatocellular carcinoma (HCC) in two large prospective cohorts [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1050.

Elevated NO2 damages the photosynthetic apparatus by inducing the accumulation of superoxide anions and peroxynitrite in tobacco seedling leaves

This study aimed to further understand the toxicity of high concentrations of nitrogen dioxide (NO2) to plants, especially to plant photosynthesis. Tobacco plants in the six-leaf stage were exposed to 16.0 μL L-1 NO2 to determine the activities of photosystem II (PSII) and photosystem I (PSI) reaction centers, the blocking site of PSII electron transport, the degree of membrane peroxidation and the relative expression of PsbA, PsbO and PsaA genes in the third fully expanded leaves by using gas exchange and chlorophyll fluorescence techniques, biochemical and RT-PCR analysis. The results showed that 16.0 μL L-1 NO2 caused necrotic lesions to form on leaves and significantly increased the generation rate of superoxide anions (O2-) and the content of peroxynitrite (ONOO-) in leaves of tobacco seedling, leading to damage to cell membrane, chlorophyll content and net photosynthetic rate reduction, and photosynthetic apparatus destruction. Fumigation with 16.0 μL L-1 NO2 decreased the activity of PSII reaction center and oxygen evolution complex, and the relative expression of PabA in leaves of tobacco seedlings to inhibit the electron transport from the donor side to the receptor side of PSII, especially blocking the electron transport from QA to QB on the receptor side. The activity of the PSI reaction center and the relative expression of PsaA decreased, weakening the ability to accept electrons and inhibiting the electron transfer from PSII to PSI, which further increased the damage of PSII of tobacco seedling leaves caused by 16.0 μL L-1 NO2. Therefore, 16.0 μL L-1 NO2 leaded to the accumulation of O2- and ONOO-, which damaged the cell membrane and thylakoid membrane, inhibit the electron transport, and destroyed the photosynthetic apparatus in leaves of tobacco seedlings. The results from this study emphasized the importance of reducing the NO2 concentration in the atmosphere.

A novel femoral artery compression device (butterfly compress) versus manual compression for hemostasis after femoral artery puncture: a randomized comparison

Objective: This study aimed to investigate the hemostatic efficacy of a novel femoral artery compression device in patients undergoing an interventional procedure through femoral artery puncture.Material and methods: Patients enrolled in this trial were randomly assigned 1:1 to the novel femoral artery compression device (NFACD) or the manual compression (MC) group. The primary endpoints were time to hemostasis (TTH), time to ambulation (TTA), any other complications, such as the occurrence of hematoma, bleeding, pseudoaneurysm and arteriovenous fistula at the puncture site, and time to hospital discharge.Results: A total of 617 patients were included in this study (NFACD, n = 308 versus MC, n = 309) from May 2017 to September 2019, and the baseline characteristics of the groups were similar. We found that the TTH and TTA were significantly shorter in the NFACD group than in the MC group (4.4 ± 11.6 min vs. 20.1 ± 22.5 min; p < 0.001; 8.9 ± 14.2 h vs. 16.3 ± 27.5 h; p = 0.002). There were few other complications in either group. In addition, there was no significant difference in time to hospital discharge between the NFACD group and the MC group.Conclusion: The novel femoral artery compression device is effective in achieving hemostasis in patients undergoing femoral artery puncture and is associated with a marked shortening of the TTH and TTA.

Toxic effects of heavy metals Pb and Cd on mulberry (Morus alba L.) seedling leaves: Photosynthetic function and reactive oxygen species (ROS) metabolism responses

To explore the mechanism of how lead (Pb) and cadmium (Cd) stress affects photosynthesis of mulberry (Morus alba L.), we looked at the effects of different concentrations of Pb and Cd stress (at 100 and 200 μmol L^-1), which are two heavy metal elements, on leaf chlorophyll (Chl), photosynthesis gas exchange, Chl fluorescence, and reactive oxygen species (ROS) metabolism in mulberry leaves. The results showed that higher concentrations of Pb and Cd reduced leaf Chl content, especially in Chl a where content was more sensitive than in Chl b. Under Pb and Cd stress, the photosynthetic carbon assimilation capacity of mulberry leaves was reduced, which was a consequence of combined limitations of stomatal and non-stomatal factors. The main non-stomatal factors were decreased photosystem II (PSII) and photosystem I (PSI) activity and carboxylation efficiency (CE). Damage to the donor side of the PSII reaction center was greater than the acceptor side. After being treated with 100 μmol L^-1 of Pb and Cd, mulberry leaves continued to be able to dissipate excess excitation energy by starting non-photochemical quenching (NPQ), but when Pb and Cd concentrations were increased to 200 μmol L^-1, the protection mechanism that depends on NPQ was impaired. Excessive excitation energy from chloroplasts promoted a great increase of ROS, such as superoxide anion (O₂^•-) and H₂O₂. Moreover, under high Pb and Cd stress, superoxide dismutase (SOD) and ascorbate peroxidase (APX) were also inhibited to some extent, and excessive ROS also resulted in a significantly higher degree of oxidative damage. Compared with Cd, the effect of Pb stress at the same concentration level displayed a significantly lower impact on Chl content, photosynthetic carbon assimilation, and stomatal conductance. Meanwhile, Pb stress mainly damaged activity of the oxygen-evolving complex (OEC) located on PSII donor side, but it reduced the electronic pressure on the PSII acceptor side and PSI. Furthermore, under Pb stress, the NPQ, SOD, and APX activity were all significantly higher than those under Cd stress. Thus under Pb stress, the degree of photoinhibition and oxidative damage of PSII and PSI in mulberry leaves were significantly lower than under Cd stress.

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) diagnosed in children and adolescents

Background

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare but potentially fatal congenital coronary anomaly associated with early infant mortality and sudden adult death. By the development or lack of coronary collateral, it can be classified as infantile or adult type. However, even with the compensatory mechanism in adult patients, there is an estimated 80 to 90% incidence of sudden death at the mean age of 35 years.

Methods

We enrolled 9 patients with ALCAPA within the age group 5 to 16 years.

Results

Only one patient developed symptoms (apsychia), whereas other patients were asymptomatic, and there was no evident left ventricular dysfunction found in any of the cases.

Conclusion

With the development of imaging techniques, asymptomatic adult-type ALCAPA patients could be identified and diagnosed in childhood or adolescence. As a potential cause of sudden death, ALCAPA should be surgically repaired soon after the diagnosis.

Physiological and proteomic responses of reactive oxygen species metabolism and antioxidant machinery in mulberry (Morus alba L.) seedling leaves to NaCl and NaHCO3 stress

In this paper, the effects of 100 mM NaCl and NaHCO₃ stress on reactive oxygen species (ROS) and physiological and proteomic aspects of ROS metabolism in mulberry seedling leaves were studied. The results showed that NaCl stress had little effect on photosynthesis and respiration of mulberry seedling leaves. Superoxide dismutase (SOD) activity and the expression of related proteins in leaves increased by varying degrees, and accumulation of superoxide anion (O₂·^-) not observed. Under NaHCO₃ stress, photosynthesis and respiration were significantly inhibited, while the rate of O₂·^- production rate and H₂O₂ content increased. The activity of catalase (CAT) and the expression of CAT (W9RJ43) increased under NaCl stress. In response to NaHCO₃ stress, the activity and expression of CAT were significantly decreased, but the ability of H₂O₂ scavenging of peroxidase (POD) was enhanced. The ascorbic acid-glutathione (AsA-GSH) cycle in mulberry seedling leaves was enhancement in both NaCl and NaHCO₃ stress. The expression of 2-Cys peroxiredoxin BAS1 (2-Cys Prx BAS1), together with thioredoxin F (TrxF), thioredoxin O1 (TrxO1), thioredoxin-like protein CITRX (Trx CITRX), and thioredoxin-like protein CDSP32 (Trx CDSP32) were significantly increased under NaCl stress. Under NaHCO₃ stress, the expression of the electron donor of ferredoxin-thioredoxin reductase (FTR), together with Trx-related proteins, such as thioredoxin M (TrxM), thioredoxin M4 (TrxM4), thioredoxin X (TrxX), TrxF, and Trx CSDP32 were significantly decreased, suggesting that the thioredoxin-peroxiredoxin (Trx-Prx) pathway's function of scavenging H₂O₂ of in mulberry seedling leaves was inhibited. Taken together, under NaCl stress, excessive production of O₂·^- mulberry seedlings leaves was inhibited, and H₂O₂ was effectively scavenged by CAT, AsA-GSH cycle and Trx-Prx pathway. Under NaHCO₃ stress, despite the enhanced functions of POD and AsA-GSH cycle, the scavenging of O₂·^- by SOD was not effective, and that of H₂O₂ by CAT and Trx-Prx pathway were inhibited; and in turn, the oxidative damage to mulberry seedling leaves could not be reduced.

Chlorophyll synthesis and the photoprotective mechanism in leaves of mulberry (Morus alba L.) seedlings under NaCl and NaHCO3 stress revealed by TMT-based proteomics analyses

Chlorophyll (Chl) and effective photoprotective mechanism are important prerequisites to ensure the photosynthetic function of plants under stress. In this study, the effects of 100 mmol L^-1 NaCl and NaHCO₃ stress on chlorophyll synthesis and photosynthetic function of mulberry seedlings were studied by physiological combined with proteomics technology. The results show that: NaCl stress had little effect on the expression of Chl synthesis related proteins, and there were no significant changes in Chl content and Chl a:b ratio. However, 13 of the 15 key proteins in the process of Chl synthesis were significantly decreased under NaHCO₃ stress, and the contents of Chl a and Chl b were significantly decreased (especially Chl a). Although stomatal conductance (G_s) decreased significantly under NaCl stress, net photosynthetic rate (P_n), PSII maximum photochemical efficiency (F_v/F_m) and electron transfer rate (ETR) did not change significantly, but under NaHCO₃ stress, not only G_s decreased significantly, PSII activity and photosynthetic carbon were the same. In the photoprotective mechanism under NaCl stress, NAD(P)H dehydrogenase (NDH)-dependent cyclic electron flow (CEF) enhanced, the expression of related proteins subunit, ndhH, ndhI, ndhK, and ndhM, the key enzyme of the xanthophyll cycle, violaxanthin de-epoxidase (VDE) were up-regulated, the ratio of (A + Z)/(V + A + Z) and non-photochemical quenching (NPQ) was increased. The expressions of proteins FTR and Fd-NiR were also significant up-regulated under NaCl stress, Fd-dependent ROS metabolism and nitrogen metabolism can effectively reduce the electronic pressure on Fd. Under NaHCO₃ stress, the expressions of NDH-dependent CEF related proteins subunit (ndhH, ndhI, ndhK, ndhM and ndhN), VDE, ZE, FTR, Fd-NiR and Fd-GOGAT, were significant down-regulated, and ZE, CP26, ndhK, ndhM, Fd-NiR, Fd-GOGAT and FTR genes expression also significantly decreased, the photoprotective mechanism, like the xanthophyll cycle，CEF and Fd-dependent ROS metabolism and nitrogen metabolism might be damaged, resulting in the inhibition of PSII electron transfer and carbon assimilation in mulberry leaves under NaHCO₃ stress.

Colorectal laterally spreading tumours : subtype evaluation by EUS and BLI and outcome of ESD

BACKGROUND AND STUDY AIMS

Colorectal laterally spreading tumour (LST) is a specific type of colonic space-occupying lesion unlike other common polypoid lesions. Here, we explored the diagnostic values of endoscopic ultrasonography (EUS) and blue laser image (BLI) in LST subtypes, their relationship with histopathological characteristics and the therapeutic effect of endoscopic submucosal dissection(ESD) for LST.

PATIENTS AND METHODS

A prospective study of 138 patients with LST was conducted. All LSTs were explored for invasion depth and superficial microstructure through EUS and BLI before ESD. Histopathological characteristics of LSTs were demonstrated through pre-operative biopsy and post-operative specimen detection. Finally, the correlations among varied morphologies, manifestations of EUS and BLI, and histopathological characteristics of LSTs were analysed comprehensively. All patients underwent follow-up after ESD.

RESULTS

Nodular-mixed and pseudodepressed subtypes were more likely to invade the submucosa, and BLI revealed a greater proportion of types B and C than the homogeneous or flat-elevated subtypes. These endoscopic features were consistent with and proved by histopathological results. Pathological severity of LST on post-ESD specimen detection was greater than that on pre-ESD biopsy analysis. En bloc R0 resection was achieved in 128 cases, and only two patients suffered recurrence during follow-up.

CONCLUSIONS

Pre-operative evaluation through EUS and BLI examination provided clues of possible pathological features and helped guide the treatment of LST. ESD is a safe and effective therapy for colorectal LST.

Cause or prevention of breast cancer with estrogens: analysis from tumor biologic data, growth kinetic model and Women's Health Initiative study

The existing medical literature suggests that estrogens may cause breast cancer but, paradoxically, can also prevent this neoplasm under specific circumstances. Appropriate interpretation of this complex data requires an understanding of emerging concepts of tumor biology. A substantial body of data, including animal models and epidemiologic studies, suggests that estrogens contribute to the development of breast cancer. Additionally, pre-clinical experiments indicate that the responsible mechanisms include both estrogen receptor α-dependent and -independent effects (ERα-dependent and ERα-independent effects). We recently developed two models to describe the growth kinetics of occult breast tumors, one based on autopsy studies and tumor doubling time and the other, computer-based. Validation of the models involved comparison of the predicted incidence of breast cancer with the actual incidence in population-based studies. Utilization of these models allowed us to determine that 16 years on average are required for tumors to undergo the 30 doubling times necessary for the occult tumors to reach the threshold for clinical detection. These models suggest that menopausal hormone therapy with estrogen plus a progestogen in the Women's Health Initiative (WHI) study accelerated the doubling time of occult, pre-existing tumors from 200 to 150 days and thus, increased the rate of tumor diagnosis. Based on estrogen-induced apoptosis data, the model accurately predicted the prevention of diagnosed breast cancer in the estrogen-alone arm of the WHI. Notably, pre-clinical studies demonstrated that conjugated equine estrogen, as used in the WHI, has unique, pro-apoptotic properties compared to the anti-apoptotic effects of estradiol, a finding providing an explanation for the reduction in breast cancer with conjugated equine estrogen.

Effects of Sulfide Flavors on AHL-Mediated Quorum Sensing and Biofilm Formation of Hafnia alvei

In this study, 10 different sulfide flavor compounds commonly used as food additives were screened for antiquorum-sensing activity. Among these, diallyl disulfide (DADS) and methyl 2-methyl-3-furyl disulfide (MMFDS) were found to exert the strongest inhibition against violacein production in Chromobacterium violaceum 026, the tested biosensor strain. DADS and MMFDS also inhibited the growth of Hafnia alvei H4, yielding MIC values of 48 and 41.6 mM, respectively. In addition, DADS and MMFDS also inhibited the ability of H. alvei H4 to produce acyl-homoserine lactone as demonstrated by the reduced level of C6-HSL in the supernatant of DADS-treated culture. At concentrations corresponding to 1/4 MIC, DADS, and MMFDS inhibited the swarming ability of H. alvei H4 by 73.50% and 76.43%, respectively, while having virtually no effect on cell growth. The same concentrations of DADS and MMFDS also completely inhibited the formation of biofilm. These antiquorum sensing effects of DADS and MMFDS involved changes in the expression of the quorum-sensing genes luxI and luxR. Quantitative RT-PCR analysis showed that the mRNA levels of both genes were significantly reduced by DADS and MMDFS at concentrations below their MICs. However, further test using a mutant strain of H. alvei lacking luxR (ΔluxR) revealed significant reduction in luxI mRNA level upon treatment of the strain with DADS or MMDFS, but no change in luxR mRNA level occurred when a luxI-lacking mutant (ΔluxI) was treated with these compounds. The result therefore suggested that the antiquorum-sensing effect of DADS and MMFDS against H. alvei H4 might operate mainly through the inhibition of luxI expression in the cells.

PRACTICAL APPLICATION

The sulfide flavors compounds used in this paper are commonly used in food processing in China and are listed in the national standard of Chinese food additives GB2760-2014. The application of sulfide flavors in food processing can enhance aroma and prevent food spoilage.

[The role of poloxamer 188 for cord blood mononuclear cells into megakaryocytes cultivation and induction in three-dimensional WAVE Bioreactor]

Objective: To observe the effect of poloxamer 188 (P188) on megakaryocyte cultivation and induction from cord blood mononuclear cells in order to obtain more megakaryocyte progenitor cells (MPC). Methods: The cord blood mononuclear cells were isolated and inoculated in cell culture bag or cell culture flask respectively. The WIGGENS shaker and cell culture bags were used to mimick WAVE Bioreactor for three-dimensional (3D) cell culture, and the P188 was added to induction medium, The cells were detected for morphology, surface marker, viability, and number on day 14. Results: In the two-dimensional (2D) culture, CD41(+), CD41(+)/CD61(+), CD61(+) megakaryocytic numbers increased significantly after adding P188 (all P<0.01). And in the 3D culture of adding P188, the cell volume became larger and the nuclear shape was irregular, the cytoplasm appeared magenta granules, and the megakaryocyte cells became more mature. By 3D culture, the expression of CD41/CD61 was (36.30±1.27)% vs (23.95±1.34)%, hence the differentiation for MPC was significantly higher than that in the 2D group (P<0.01). Furthermore, adding P188 in 3D culture resulted in highest differentiation efficiency for MPC [(59.45±1.20)%]. There were no significantly differences in terms of cell viability and cell number among 3D culture containing P188, 2D and 3D culture groups (all P>0.05). Conclusion: 3D culture was beneficial for the differentiation of MPC, but the cell viability was lower than 2D group; However, the satisfied cell growth and better induction efficiency were obtained by adding of P188, which might provide a new method of megakaryocytes production for clinical application.

Mesenchymal stem cells inhibit T cell activation by releasing TGF-β1 from TGF-β1/GARP complex

Intervention with mesenchymal stem cells (MSCs) reveals a promising therapeutic tool to treat transplantation and autoimmune disease due to their immunoregulation capability. But the mechanisms of action are not fully investigated yet. Transforming growth factor-β1 (TGF-β1) exhibit multiple effects in migration, differentiation, and immunomodulation of MSCs. Glycoprotein A repetitions predominant (GARP) is an important marker of activated Treg (regulatory T cells). GARP binds latent TGF-β1 to regulate its activation, which is the indispensable step in Treg suppressing effector T cells. So far we don't know whether GARP present on MSCs and its association with MSCs function. Our study show that MSCs express GARP which binds latent TGF-β1 on their cell surface. We also found that TGF-β1+/- MSCs produce less TGF-β1 and exhibit reduced capacity in inhibiting T cells. When TGF-β1 signaling pathway was blocked, MSCs show decreased activity in inhibiting T cells. Importantly, silencing GARP expression distinctively damaged the capacity of MSCs to inhibit IFN-γ production. These findings indicated the expression of GARP on MSCs and its functionality in activating LAP, thus demonstrating GARP as a novel biomarker and new target to improve the therapeutic efficacy of MSCs.

Secreted GRP78 activates EGFR-SRC-STAT3 signaling and confers the resistance to sorafeinib in HCC cells

Acquired resistance is a common phenomenon for HCC patients who undergone sorafenib treatment, however the mechanism by which acquired resistance develops remains elusive. In this study, we found that GRP78 could be detected in the serum samples of HCC patients and the conditional medium of multiple HCC cell lines, suggesting that GRP78 is secreted by HCC cells. Further studies showed that secreted GRP78 facilitated the proliferation and inhibited the apoptosis induced by sorafenib both in HCC cell lines and in tumor xenografts. We further found that secreted GRP78 could interact physically with EGFR, therefore activates EGFR signaling pathway. knockdown of EGFR decreased secreted GRP78 induced phosphorylation of SRC and STAT3. By contrast, overexpression of EGFR further enhanced the phosphorylation of SRC and STAT3 induced by secreted GRP78, suggesting the critical role of EGFR in secreted GRP78 conferred resistance to sorafeinib. Moreover, inhibition of SRC by PP2 antagonized the resistance to sorafenib and inhibited the activation of STAT3 conferred by secreted GRP78. Taken together, our results showed that secreted GRP78 could interact with EGFR, activate EGFR-SRC-STAT3 signaling, conferring the resistance to sorafenib.

[Dynamic change of population structure of Oncomelania hupensis]

Objective To understand the successive dynamic change of population structure of Oncomelania hupensis during a one-year period, so as to provide the evidence for snail control. Methods A river beach and a ditch infested with O. hupensis snails were selected and longitudinally investigated in the midmonth during one year. The snail survey indices included the survival status, gender, number of whorls, length and width of shell, and gonad development status (measured by the color depth of gonad and the length ratio of gonad to liver), and the monthly snail eggs in the soil were collected and counted simultaneously. In addition, the temperature and humidity of the soil and the daily data of air temperature and precipitation were measured or collected during the study period (every month). Results Both survival rate of snails and live snail density at the two environments were positively correlated with the temperatures of air and soil. With a slight bimodal distribution, the snail survival rate peaked from May to June, and in September. The living snail densities got the highest level in July and September in the river beach, and from April to May in the ditch. The regression equations of snail length (L) and width (W) were L_beach = 2.355 + 1.678W (F = 2 989.43, P < 0.01) and L_ditch = 0.478 + 2.091W (F = 2.989.43, P < 0.01), respectively. The snails were the ones with 4.07-11.81 mm in the length (8.98 ± 0.92) mm in the river beach, and the snails were the ones with 3.63-9.92 mm in the length (7.03 ± 0.82) mm in the ditch. The main snails were the ones with five to eight whorls of shell in the river beach and four to seven whorls of shell in the ditch. The proportions of snails with less than or equal to five whorls (in the river beach) and four (in the ditch) were the highest in May and September, about 20%. The ratios of male and female snails were 1.66 in the river beach and 1.22 in the ditch, respectively. The gonad development status of male and female snails was basically synchronous and had a bimodal abundance period - from April to May and September to October. The numbers of snail eggs in the soil among months were significantly different, reaching the highest in June in the river beach (100.8/0.1 m²), and May in the ditch (82.5/ 0.1 m²). Conclusion The principal periods of breeding and alternation of generations of snails are April-May and SeptemberOctober every year, which should also be the optimal time for mollusciciding in schistosomiasis susceptible zones.