Endoscopic construction of an antireflux mucosal barrier for the treatment of GERD: a pilot study (with video).

BACKGROUND AND AIMS: Based on the porcine natural antireflux mechanism, we developed a novel endoscopic procedure to build an antireflux mucosal flap to block acid reflux and treat GERD. METHODS: The antireflux mucosal valvuloplasty (ARMV) procedure is performed by releasing and reconstructing three-fourths of the circumference of cardiac mucosa at the lesser curvature side into a double-layer mucosal flap. The mucosal flap works together with cardiac scarring to block reflux. We retrospectively reviewed 30 patients who underwent ARMV from 2019 to 2021. Subjective and objective data evaluating GERD were collected before and after ARMV. RESULTS: All 30 ARMV procedures were performed successfully, with a mean operation time of 72.6 ± 20.3 minutes. One patient had postoperative bleeding that required endoscopic hemostasis. The mean follow-up time was 28.9 ± 13.9 months. Twenty-five of 30 patients (83.3%) and 23 of 26 patients (88.5%) reported discontinuation or reduction in proton pump inhibitor therapy 3 months and 1 year after ARMV, respectively. GERD questionnaire and GERD Health-Related Quality of Life questionnaire scores improved significantly from 14.0 ± 2.6 and 48.7 ± 15.0, respectively, before ARMV to 7.7 ± 2.5 and 10.2 ± 5.9, respectively, 12 months after ARMV (P < .0001 in both comparisons). Eleven patients received 24-hour esophageal pH monitoring before and after ARMV. The mean acid exposure time and DeMeester score dropped from 56.9% ± 23.7% and 167.1 ± 80.1, respectively, before ARMV to 5.5% ± 3.0% and 18.6 ± 11.9, respectively, after ARMV (P < .0001 in both comparisons). CONCLUSIONS: This pilot study showed that ARMV is a safe, feasible, and effective procedure for GERD patients. Further prospective and comparative trials are needed to confirm its role among endoscopic antireflux therapies.

Heparin impairs angiogenesis through inhibition of microRNA-10b.

Heparin, which has been used as an anticoagulant drug for decades, inhibits angiogenesis, whereas thrombin promotes tumor-associated angiogenesis. However, the mechanisms underlying the regulation of angiogenesis by heparin and thrombin are not well understood. Here, we show that microRNA-10b (miR-10b) is down-regulated by heparin and up-regulated by thrombin in human microvascular endothelial cells (HMEC-1). Overexpression of miR-10b induces HMEC-1 cell migration, tube formation, and angiogenesis, and down-regulates homeobox D10 (HoxD10) expression via direct binding of miR-10b to the putative 3' UTR of HoxD10. In addition, HMEC-1 cell migration and tube formation are induced by HoxD10 knockdown, whereas angiogenesis is arrested when HoxD10 expression is increased after anti-miR-10b or heparin treatments. Furthermore, expression of miR-10b and its transcription factor Twist are up-regulated by thrombin, whereas HoxD10 expression is impaired by thrombin. Using quartz crystal microbalance analysis, we show that heparin binds to thrombin, thereby inhibiting thrombin-induced expression of Twist and miR-10b. However, the expression of miR-10b is not attenuated by heparin any more after thrombin expression is silenced by its siRNA. Interestingly, we find that heparin attenuates miR-10b expression and induces HoxD10 expression in vivo to inhibit angiogenesis and impair the growth of MDA-MB-231 tumor xenografts. These results provide insight into the molecular mechanism by which heparin and thrombin regulate angiogenesis.

Structure of a ß-glucan from Grifola frondosa and its antitumor effect by activating Dectin-1/Syk/NF-κB signaling.

A soluble homogeneous ß-glucan, GFPBW1, with a molecular mass of 300 kDa was purified from the fraction of the fruit bodies of Grifola frondosa extracted with 5% NaOH. Using various methods, such as infrared spectroscopy, NMR, methylation and monosaccharide composition analysis, its structure was determined to be a ß-D-(1-3)-linked glucan backbone with a single ß-D-(1-6)-linked glucopyranosyl residue branched at C-6 on every third residue. It induced TNF-α and IL-6 production and the activation of Syk and NF-κB signaling in resident peritoneal macrophages from ICR mice, which could be significantly inhibited by the blocking reagent laminarin. A competitive phagocytosis assay with FITC-zymosan indicated that GFPBW1 could bind to DC-associated C-type lectin 1 (Dectin-1). The TNF-α secretion and activation of Syk/NF-κB signaling triggered by GFPBW1 were enhanced in RAW264.7 cells overexpressing wild but not mutant (Δ38 and Y15S) Dectin-1. Furthermore, GFPBW1 potentiated the Concanavalin A-induced proliferative response of splenocytes and inhibited Sarcoma-180 growth allografted in ICR mice but not in immunodeficient BALB/c nu/nu mice. These results suggested that the antitumor activity of GFPBW1 was partially associated with the activation of macrophages via the Dectin-1/Syk/NF-κB signaling pathway. This molecule could be a promising biological response modifier with clear application for antitumor therapies.

Molecular characterization and expression analysis of dihydroflavonol 4-reductase (DFR) gene in Saussurea medusa.

Dihydroflavonol 4-reductase (DFR), which catalyzes the reduction of dihydroflavonols to leucoanthocyanins, is a key enzyme in the biosynthesis of anthocyanidins, proanthocyanidins, and other flavonoids of importance in plant development and human nutrition. This study isolated a full length cDNA encoding DFR, designated as SmDFR (GenBank Accession No. EF600682), by screening a cDNA library from a red callus line of Saussurea medusa, which is an endangered, traditional Chinese medicinal plant with high pharmacological value. SmDFR was functionally expressed in yeast (Saccharomyces cerevisiae) to confirm that SmDFR can readily reduce dihydroquercetin (DHQ) and dihydrokampferol (DHK), but it could not reduce dihydromyricetin (DHM). The deduced SmDFR structure shared extensive sequence similarity with previously characterized plant DFRs and phylogenetic analysis showed that it belonged to the plant DFR super-family. SmDFR also possessed flavanone 4-reductase (FNR) activity and can catalyze the conversion of eridictyol to luteoforol. Real-time PCR analysis showed that the expression level of SmDFR was higher in flowers compared with both leaves and roots. This work greatly enhances our knowledge of flavonoid biosynthesis in S. medusa and marks a major advance that could facilitate future genetic modification of S. medusa.

Lobolide, a diterpene, blockades the NF-κB pathway and p38 and ERK MAPK activity in macrophages in vitro.

AIM: Recent studies have shown that constitutive activation of the nuclear factor κB (NF-κB) plays a key role in chronic inflammation and cancers. The aim of this study was to characterize lobolide, a cembrane diterpene, as a drug candidate targeting the NF-κB signaling pathway. METHODS: A HEK 293/NF-κB-Luc stable cell line was constructed to evaluate the effect of lobolide on NF-κB activation. THP-1 human monocytes and peripheral blood mononuclear cells (PBMCs) from healthy volunteers were tested. Lipopolysaccharide (LPS)-induced TNFα and IL-1ß production and activation of the TAK1-IKK-NF-κB pathway were studied using ELISA and Western blot analysis. RESULTS: In HEK 293/NF-κB-Luc stable cells, lobolide (0.19-50 µmol/L) inhibited NF-κB activation in a concentration-dependent manner with an IC(50) value of 4.2 ± 0.3 µmol/L. Treatment with lobolide (2.5-10 µmol/L) significantly suppressed LPS-induced production of TNFα and IL-1ß in both THP-1 cells and PBMCs. In THP-1 cells, the suppression was partially caused by blockade of the translocation of NF-κB from the cytoplasm to the nucleus via affecting the TAK1-IKK-NF-κB pathway and p38 and ERK MAPK activity. CONCLUSION: Lobolide is a potential inhibitor of the NF-κB pathway, which blocks the translocation of NF-κB from the cytoplasm to the nucleus. Lobolide inhibits LPS-stimulated TNFα and IL-1ß release, suggesting that the compound might be an anti-inflammatory compound.

Bergman projections on weighted Fock spaces in several complex variables.

Let ϕ be a real-valued plurisubharmonic function on [Formula: see text] whose complex Hessian has uniformly comparable eigenvalues, and let [Formula: see text] be the Fock space induced by ϕ. In this paper, we conclude that the Bergman projection is bounded from the pth Lebesgue space [Formula: see text] to [Formula: see text] for [Formula: see text]. As a remark, we claim that Bergman projections are also well defined and bounded on Fock spaces [Formula: see text] with [Formula: see text]. We also obtain the estimates for the distance induced by ϕ and the [Formula: see text]-norm of Bergman kernel for [Formula: see text].

Abnormal pinocytosis and valence-variable behaviors of cerium suggested a cellular mechanism for plant yield reduction induced by environmental cerium.

The environmental safety of cerium (Ce) applications in many fields has been debated for almost a century because the cellular effects of environmental Ce on living organisms remain largely unclear. Here, using new, interdisciplinary methods, we surprisingly found that after Ce(III) treatment, Ce(III) was first recognized and anchored on the plasma membrane in leaf cells. Moreover, some trivalent Ce(III) was oxidized to tetravalent Ce(IV) in this organelle, which activated pinocytosis. Subsequently, more anchoring sites and stronger valence-variable behavior on the plasma membrane caused stronger pinocytosis to transport Ce(III and IV) into the leaf cells. Interestingly, a great deal of Ce was bound on the pinocytotic vesicle membrane; only a small amount of Ce was enclosed in the pinocytotic vesicles. Some pinocytic vesicles in the cytoplasm were deformed and broken. Upon breaking, pinocytic vesicles released Ce into the cytoplasm, and then these Ce particles self-assembled into nanospheres. The aforementioned special behaviors of Ce decreased the fluidity of the plasma membrane, inhibited the cellular growth of leaves, and finally, decreased plant yield. In summary, our findings directly show the special cellular behavior of Ce in plant cells, which may be the cellular basis of plant yield reduction induced by environmental Ce.

Methyl jasmonate stimulates jaceosidin and hispidulin production in cell cultures of Saussurea medusa.

Cell cultures of Saussurea medusa produce valuable secondary metabolites, and jaceosidin and hispidulin are the major bioactive compounds. In the present study, the cultures were challenged by methyl jasmonate (MJ). The highest jaceosidin and hispidulin concentrations (65.2 +/- 3.67 mg/L and 12.3 +/- 0.47 mg/L) were achieved with 5 microM MJ added to 9-d-old subcultures, being 2.2-fold and 4.2-fold, respectively, higher than those from controls. The elicitor had little influence on cell growth, indicating that the changed biological processes did not include alterations in cell division. Furthermore, we observed that the activities of phenylalanine ammonia lyase were transiently increased after treatment with MJ, which suggests that this elicitor modifies jaceosidin and hispidulin production by regulating the phenylpropanoid pathway.

Interaction between La(III) and proteins on the plasma membrane of horseradish.

Lanthanum (La) is an important rare earth element in the ecological environment of plant. The proteins on the plasma membrane control the transport of molecules into and out of cell. It is very important to investigate the effect of La(III) on the proteins on the plasma membrane in the plant cell. In the present work, the interaction between La(III) and proteins on the plasma membrane of horseradish was investigated using optimization of the fluorescence microscopy and fluorescence spectroscopy. It is found that the fluorescence of the complex system of protoplasts and 1-aniline Kenai-8-sulfonic acid in horseradish treated with the low concentration of La(III) is increased compared with that of the control horseradish. The opposite effect is observed in horseradish treated with the high concentration of La(III). These results indicated that the low concentration of La(III) can interact with the proteins on the plasma membrane of horseradish, causing the improvement in the structure of proteins on the plasma membrane. The high concentration of La(III) can also interact with the proteins on the plasma membrane of horseradish, leading to the destruction of the structure of proteins on the plasma membrane. We demonstrate that the proteins on the plasma membrane are the targets of La(III) action on plant cell.

Living target of Ce(III) action on horseradish cells: proteins on/in cell membrane.

Positive and negative effects of rare earth elements (REEs) in life have been reported in many papers, but the cellular mechanisms have not been answered, especially the action sites of REEs on plasma membrane are unknown. Proteins on/in the plasma membrane perform main functions of the plasma membrane. Cerium (Ce) is the richest REEs in crust. Thus, the interaction between Ce(III) and the proteins on/in the plasma membrane, the morphology of protoplast, and the contents of nutrient elements in protoplast of horseradish were investigated using the optimized combination of the fluorescence microscopy, fluorescence spectroscopy, circular dichroism, scanning electron microscopy, and X-ray energy dispersive spectroscopy. It was found that Ce(III) at the low concentrations (10, 30 µM) could interact with proteins on/in the plasma membrane of horseradish, leading to the improvement in the structure of membrane proteins and the plasma membrane, which accelerated the intra-/extra-cellular substance exchange and further promoted the development of cells. When horseradish was treated with Ce(III) at the high concentrations (60, 80 µM), Ce(III) also could interact with the proteins on/in the plasma membrane of horseradish, leading to the destruction in the structure of membrane proteins and the plasma membrane. These effects decelerated the intra-/extra-cellular substance exchange and further inhibited the development of cells. Thus, the interaction between Ce(III) and proteins on/in the plasma membrane in plants was an important reason of the positive and negative effects of Ce(III) on plants. The results would provide some references for understanding the cellular effect mechanisms of REEs on plants.