MicroRNA-155 inhibition attenuates myocardial infarction-induced connexin 43 degradation in cardiomyocytes by reducing pro-inflammatory macrophage activation.

Background: Degradation of pro-inflammatory macrophage-mediated connexin 43 (Cx43) plays an important role in post-myocardial infarction (MI) arrhythmogenesis, microRNA (miR)-155 produced by macrophages has been shown to mediate post-MI effects. We hypothesized that miR-155 inhibition attenuated MI-induced Cx43 degradation by reducing pro-inflammatory macrophage activation. Methods: MI was induced by permanent ligation of the left anterior descending coronary artery in male C57BL/6 mice. Lipopolysaccharide (LPS)-stimulated mice bone marrow-derived macrophages (BMDMs) and hypoxia-induced neonatal rat cardiomyocytes (NRCMs) were used in vitro models. qRT-PCR, Western-blot and immunofluorescence were used to analyze relevant indicators. Results: The expression levels of miR-155, interleukin-1 beta (IL-1ß), and matrix metalloproteinase (MMP)7 were higher in MI mice and LPS-treated BMDMs than in the sham/control groups, treatment with a miR-155 antagomir reversed these effects. Moreover, miR-155 inhibition reduced ventricular arrhythmias incidence and improved cardiac function in MI mice. Cx43 expression was decreased in MI mice and hypoxia-exposed NRCMs, and hypoxia-induced Cx43 degradation in NRCMs was reduced by application of conditioned medium from LPS-induced BMDMs treated with the miR-155 antagomir, but increased by conditioned medium from BMDMs treated with a miR-155 agomir. Importantly, NRCMs cultured in conditioned medium from LPS-induced BMDMs transfected with small interfering RNA against IL-1ß and MMP7 showed decreased hypoxia-mediated Cx43 degradation, and this effect also was diminished by BMDM treatment with the miR-155 agomir. Additionally, siRNA-mediated suppressor of cytokine signaling 1 (SOCS1) knockdown in LPS-induced BMDMs promoted Cx43 degradation in hypoxia-exposed NRCMs, and the effect was reduced by the miR-155 inhibition. Conclusions: MiR-155 inhibition attenuated post-MI Cx43 degradation by reducing macrophage-mediated IL-1ß and MMP7 expression through the SOCS1/nuclear factor-κB pathway.

PU.1 inhibition attenuates atrial fibrosis and atrial fibrillation vulnerability induced by angiotensin-II by reducing TGF-ß1/Smads pathway activation.

Fibrosis serves a critical role in driving atrial remodelling-mediated atrial fibrillation (AF). Abnormal levels of the transcription factor PU.1, a key regulator of fibrosis, are associated with cardiac injury and dysfunction following acute viral myocarditis. However, the role of PU.1 in atrial fibrosis and vulnerability to AF remain unclear. Here, an in vivo atrial fibrosis model was developed by the continuous infusion of C57 mice with subcutaneous Ang-II, while the in vitro model comprised atrial fibroblasts that were isolated and cultured. The expression of PU.1 was significantly up-regulated in the Ang-II-induced group compared with the sham/control group in vivo and in vitro. Moreover, protein expression along the TGF-ß1/Smads pathway and the proliferation and differentiation of atrial fibroblasts induced by Ang-II were significantly higher in the Ang-II-induced group than in the sham/control group. These effects were attenuated by exposure to DB1976, a PU.1 inhibitor, both in vivo and in vitro. Importantly, in vitro treatment with small interfering RNA against Smad3 (key protein of TGF-ß1/Smads signalling pathway) diminished these Ang-II-mediated effects, and the si-Smad3-mediated effects were, in turn, antagonized by the addition of a PU.1-overexpression adenoviral vector. Finally, PU.1 inhibition reduced the atrial fibrosis induced by Ang-II and attenuated vulnerability to AF, at least in part through the TGF-ß1/Smads pathway. Overall, the study implicates PU.1 as a potential therapeutic target to inhibit Ang-II-induced atrial fibrosis and vulnerability to AF.

Halogen Inhalation-Induced Lung Injury and Acute Respiratory Distress Syndrome.

OBJECTIVE: Exposure to halogens, such as chlorine or bromine, results in environmental and occupational hazard to the lung and other organs. Chlorine is highly toxic by inhalation, leading to dyspnea, hypoxemia, airway obstruction, pneumonitis, pulmonary edema, and acute respiratory distress syndrome (ARDS). Although bromine is less reactive and oxidative than chlorine, inhalation also results in bronchospasm, airway hyperresponsiveness, ARDS, and even death. Both halogens have been shown to damage the systemic circulation and result in cardiac injury as well. There is no specific antidote for these injuries since the mechanisms are largely unknown. DATA SOURCES: This review was based on articles published in PubMed databases up to January, 2018, with the following keywords: "chlorine," "bromine," "lung injury," and "ARDS." STUDY SELECTION: The original articles and reviews including the topics were the primary references. RESULTS: Based on animal studies, it is found that inhaled chlorine will form chlorine-derived oxidative products that mediate postexposure toxicity; thus, potential treatments will target the oxidative stress and inflammation induced by chlorine. Antioxidants, cAMP-elevating agents, anti-inflammatory agents, nitric oxide-modulating agents, and high-molecular-weight hyaluronan have shown promising effects in treating acute chlorine injury. Elevated free heme level is involved in acute lung injury caused by bromine inhalation. Hemopexin, a heme-scavenging protein, when administered postexposure, decreases lung injury and improves survival. CONCLUSIONS: At present, there is an urgent need for additional research to develop specific therapies that target the basic mechanisms by which halogens damage the lungs and systemic organs.

EZH2 promotes cell migration and invasion but not alters cell proliferation by suppressing E-cadherin, partly through association with MALAT-1 in pancreatic cancer.

Enhancer of zeste homolog 2 (EZH2) is an essential component of the polycomb repressive complex 2 (PRC2), which is required for epigenetic silencing of target genes, including those affecting cancer progression. Its role in pancreatic cancer remains to be clarified; therefore, we investigated the effects of aberrantly expressed EZH2 on pancreatic cancer. We found that EZH2 expression is up-regulated in pancreatic cancer tissues and positively correlated with lymph node metastasis and advanced clinical stage in pancreatic cancer patients. EZH2 knockdown in pancreatic cancer cell lines inhibited cell migration and invasion, but did not alter cell proliferation. Silencing of EZH2 also increased E-cadherin expression in vitro, and E-cadherin expression was inversely correlated with EZH2 expression in pancreatic cancer tissue samples. Patients with high EZH2 and low E-cadherin expression had the worst prognosis. RIP and ChIP assays suggest that EZH2 is recruited to the E-cadherin promoter by the long non-coding RNA, MALAT-1 (metastasis associated in lung adenocarcinoma transcript 1), where it represses E-cadherin expression. Our results show that EZH2-based therapies may be an option for the treatment of pancreatic cancer.

[Characteristics of Hydrogen and Oxygen Isotopes of Soil Water in the Water Source Area of Yuanyang Terrace].

Stable isotope techniques provide a new approach to study soil water movement. The precipitation and the soil water from 0 to 100 cm soil layer in 4 kinds of typical vegetation types (forest, shrub forest, grassland and non-forest land) over the water source area of Yuanyang terrace were sampled, and their isotope compositions were analyzed, aimed to understand the characteristics of stable isotopes in different depth of the soil water. The results showed that the meteoric water line in the water source area of Yuanyang terrace was δD = 6.838 4δ(18)O-5.6921 (R2 = 0.8787, n = 20), the slope and intercept were less than the global atmospheric precipitation. The hydrogen and oxygen stable isotopes in the soil water of the 4 kinds of typical types was lower than the local meteoric water line side and the fluctuation of isotope value on surface soil profile was greater. With the increasing soil depth, the fluctuation of delta 18O value was smaller and smaller, especially in the 80-100 cm soil layer which was the most obvious. The delta 18O values of the deep soil water in forest and grassland were higher than that in the surface soil. while it was on the contrary in shrub forest and non-forest land.

Meta-analysis comparing the safety and efficacy of metastatic colorectal cancer treatment regimens, capecitabine plus irinotecan (CAPIRI) and 5-fluorouracil/leucovorin plus irinotecan (FOLFIRI).

The relative efficacy and safety of first-line metastatic colorectal cancer (mCRC) treatment regimens, capecitabine with irinotecan (CAPIRI) and 5-fluorouracil/leucovorin plus irinotecan (FOLFIRI), are not well defined. We identified and subsequently examined seven independent, randomized controlled clinical trials, performing a meta-analysis to compare these two treatment regimens. Using Medline, EMBASE, Cochrane Library (CENTRAL), and the American Society of Clinical Oncology Annual Meeting to search available literature until February 2014, we identified seven studies comparing safety and efficacy of CAPIRI and FOLFIRI in mCRC patients. These studies were pooled and evaluated for rates of progression-free survival (PFS), objective response rate (ORR), overall survival (OS), and diarrhea. CAPIRI and FOLFIRI demonstrated similar efficacy outcomes, though CAPIRI was associated with a higher incidence of diarrhea. CAPIRI and FOLFIRI are equally effective options for first-line treatment of mCRC.

MiR-21 upregulation induced by promoter zone histone acetylation is associated with chemoresistance to gemcitabine and enhanced malignancy of pancreatic cancer cells.

BACKGROUND AND AIMS: MicroRNA-21 (miR-21) is reported to be overexpressed and to contribute to proliferation, apoptosis and gemcitabine resistance in pancreatic ductal adenocarcinomas (PDACs). The aims of this study were to explore regulation of miR-21 expression by epigenetic change and its impact on chemoresistance and malignant properties of of pancreatic cancer. MATERIALS AND METHODS: We retrospectively collected 41 cases of advanced pancreatic cancer patients who were sensitive or resistant to gemcitabine and assessed levels of serum circulating miR-21 for correlation with cytotoxic activity. Histone acetylation in the miR-21 promoter was also studied in gemcitabine-sensitive and gemcitabine-resistant PDAC cells. Gemcitabine-resistant HPAC and PANC-1 cells were transfected with pre-miR-21 precursors (pre-miR-21) and antisense oligonucleotides (anti-miR-21), and were treated with TSA. Finally, invasion and metastasis assays were performed and alteration in mir-21, PTEN, AKT and pAKT level was evaluated in these cells. RESULTS: Serum miR-21 levels were increased in gemcitabine- resistant PDAC patients compared with gemcitabine-sensitive subjects. The miR-21 levels were increased in 6 PDAC cells treated with gemcitabine significantly, associated with 50% inhibitory concentrations (IC50s). Histone acetylation levels at miR-21 promoter were increased in PDAC cells after treatment with gemcitabine. Enhanced invasion and metastasis, increased miR-21 expression, decreased PTEN, elevated pAKT level were demonstrated in gemcitabine-resistant HPAC and PANC-1 cells. Pre-miR-21 transfection or TSA treatment further increased invasion and metastasis ability, decreased PTEN, and elevated pAKT levels in these two lines. In contrast, anti-miR-21 transfection could reverse invasion and metastasis, and PTEN and pAKT expressions induced by gemcitabine. CONCLUSIONS: MiR-21 upregulation induced by histone acetylation in the promoter zone is associated with chemoresistance to gemcitabine and enhanced malignant potential in pancreatic cancer cells.

[Role of pharmacokinetic monitoring of serum fluorouracil concentration in patients with local advanced and metastatic colorectal cancer and further improving efficacy of fluorouracil-based chemotherapy].

OBJECTIVE: To investigate the relationship between serum concentration of fluorouracil and therapeutic efficacy as well as adverse reactions in patients with unresectable locally advanced or measurable metastatic colorectal cancer, and to analyze its role in further improving therapeutic efficacy and reducing adverse reactions of fluorouracil-based chemotherapy. METHODS: Eighty-six patients were randomly assigned into three groups according to the average plasma concentration of fluorouracil after three cycles of chemotherapy with the initial regimen of two weeks FOLFOX-4 (oxaliplatin + leucovorin + fluorouracil) or FOLFIRI (irinotecan + leucovorin + fluorouracil): group 1 (plasma concentration of fluorouracil < 25 ng/ml), group 2 (25 - 35 ng/ml) and group 3 (> 35 ng/ml). The blood samples were taken at 12 h after continuous infusion of fluorouracil in each cycle and the plasma concentration of fluorouracil was detected by high performance liquid chromatography (HPLC) (about 5 am ± 1 h). The relationship between the drug plasma concentration, therapeutic efficacy and adverse reactions in different fluorouracil plasma concentration arms was analyzed retrospectively. RESULTS: The average plasma concentrations of fluorouracil of the three groups were (23.48 ± 1.95) ng/ml, (31.47 ± 2.33) ng/ml and (39.89 ± 3.87) ng/ml, respectively (P < 0.01). As for therapeutic efficacy, the median OS of the groups 2 and 3 were 18.0 and 17.5 months, significantly higher than that in the group 1 (13.0 months, P < 0.01). The PFS were 4.5, 7.5 and 8.0 months, respectively (P < 0.01). In terms of adverse reactions, the incidences of bone marrow suppression, mucositis and diarrhea in the group 3 were significantly higher than that in the first two groups (P = 0.02, P = 0.04 and P = 0.02). CONCLUSIONS: The patients with local advanced and metastatic colorectal cancer, receiving fluorouracil-based chemotherapy, and with an average plasma concentration of fluorouracil between 25 - 35 mg/L have a better prognosis, and lower incidence of adverse reactions such as bone marrow suppression, mucositis and diarrhea.

[Analyze on chemical compositions of Dalbergia odorifera essential oils extracted by CO2-supercritical-fluid-extraction and steam distillation extraction].

OBJECTIVE: To analyze the chemical compositions of Dalbergia odorifera essential oils extacted by CO2-supercritical-fluid-extraction (SFE-CO2) and steam distillation extraction (SD). METHODS: The essential oils of Dalbergia odorifera were extracted by steam distillation extraction and SFE-CO2. The chemical components were separated and analyzed by gas chromatography-mass spectrometry. RESULTS: 12 compounds were identified in SFE sample. The major components from essential oils were 2-propenoic acid-3(4-methoxyphenyl)-ethyl ester (14.53%), nerolidol (14.95%), ageratochromene (1.33%). 9 compounds were identified in SD sample. The major components from essential oils were nerolidol (26.61%), cedrol (1.65%). CONCLUSION: The SFE method is better than the SD method in reliability stability and reproducibility, and suitable for essential oils extraction of Dalbergia odorifera.

Regulation of epithelial sodium channels by cGMP/PKGII.

Airway and alveolar fluid clearance is mainly governed by vectorial salt movement via apically located rate-limiting Na(+) channels (ENaC) and basolateral Na(+)/K(+)-ATPases. ENaC is regulated by a spectrum of protein kinases, i.e. protein kinase A (PKA), C (PKC), and G (PKG). However, the molecular mechanisms for the regulation of ENaC by cGMP/PKG remain to be elucidated. In the present study, we studied the pharmacological responses of native epithelial Na(+) channels in human Clara cells and human alphabetagammadelta ENaCs expressed in oocytes to cGMP. 8-pCPT-cGMP increased amiloride-sensitive short-circuit current (I(sc)) across H441 monolayers and heterologously expressed alphabetagammadelta ENaC activity in a dose-dependent manner. Similarly, 8-pCPT-cGMP (a PKGII activator) but not 8-Br-cGMP (a PKGI activator) increased amiloride-sensitive whole cell currents in H441 cells in the presence of CFTRinh-172 and diltiazem. In all cases, the cGMP-activated Na(+) channel activity was inhibited by Rp-8-pCPT-cGMP, a specific PKGII inhibitor. This was substantiated by the evidence that PKGII was the sole isoform expressed in H441 cells at the protein level. Importantly, intratracheal instillation of 8-pCPT-cGMP in BALB/c mice increased amiloride-sensitive alveolar fluid clearance by approximately 30%, consistent with the in vitro results. We therefore conclude that PKGII is an activator of lung epithelial Na(+) channels, which may expedite the resolution of oedematous fluid in alveolar sacs.

1,3,5-Tris(N-phenyl-benzimidazol-2-yl)benzene methanol solvate.

The main mol-ecule of the title compound, C(45)H(30)N(6)·CH(3)OH, has a non-planar core: the dihedral angles between the benzimidazole rings and the central benzene ring are 20.19 (10), 34.57 (8), and 44.59 (8)°, while the dihedral angles between the peripheral phenyl rings and the attached benzimidazole rings are 84.57 (7), 62.71 (6) and 51.73 (6)°. The tri-substituted benzene mol-ecule is connected to the methanol solvent mol-ecule through an O-H⋯N hydrogen bond, forming a 1:1 solvate. In the crystal structure, no significant π-π inter-actions are present, and the mol-ecules are associated through weak C-H⋯N and C-H⋯O(methanol) contacts.

catena-Poly[[silver(I)-µ-dipyrazin-2-ylamine] perchlorate monohydrate].

In the title complex, {[Ag(C(8)H(7)N(5))]ClO(4)·H(2)O}(n), the multidentate dipyrazin-2-ylamine acts as a µ(2)-bridging link with an anti-syn configuration, assembling the Ag(I) ions into a zigzag chain structure. The Ag(I) ion is linearly coordinated by two dipyrazin-2-ylamine ligands through two pyrazine N atoms. (ClO(4) (-))⋯π(pyrazine) [O⋯centroid distances of 3.612 (3) and 3.664 (1) Å] and π-π inter-actions [centroid-centroid distance = 3.518 (2) Å] as well as O-H⋯O and N-H⋯O hydrogen-bonds assemble the chains into a three-dimensional supra-molecular aggregation.