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Endogenous transfer RNA‐derived small RNAs (tsRNAs) are newly identified RNAs that are closely associated with the pathogenesis of multiple diseases, but the involvement of tsRNAs in regulating acute pancreatitis (AP) development has not been reported. In this study, we screened out a novel tsRNA, tRF3‐Thr‐AGT, that was aberrantly downregulated in the acinar cell line AR42J treated with sodium taurocholate (STC) and the pancreatic tissues of STC‐induced AP rat models. In addition, STC treatment suppressed cell viability, induced pyroptotic cell death and cellular inflammation in AP models in vitro and in vivo. Overexpression of tRF3‐Thr‐AGT partially reversed STC‐induced detrimental effects on the AR42J cells. Next, Z‐DNA‐binding protein 1 (ZBP1) was identified as the downstream target of tRF3‐Thr‐AGT. Interestingly, upregulation of tRF3‐Thr‐AGT suppressed NOD‐like receptor protein 3 (NLRP3)‐mediated pyroptotic cell death in STC‐treated AR42J cells via degrading ZBP1. Moreover, the effects of tRF3‐Thr‐AGT overexpression on cell viability and inflammation in AR42J cells were abrogated by upregulating ZBP1 and NLRP3. Collectively, our data indicated that tRF3‐Thr‐AGT suppressed ZBP1 expressions to restrain NLRP3‐mediated pyroptotic cell death and inflammation in AP models. This study, for the first time, identified the role and potential underlying mechanisms by which tRF3‐Thr‐AGT regulated AP pathogenesis.

The morphology and the structure of βF′ metastable phase were studied in aged binary Mg Nd alloy by atomic-resolution scanning transmission electron microscopy (STEM). The proposed three categories of βF′ − βF′ configurations are respectively aligned, staggered and inserted configurations, which can explain well the β′′′ structure proposed previously based on the experimental images and constructed models. The inserted βF′ − βF′ configuration is the most important one during the structural evolution of aging, which play a crucial role in the in-situ transformation from the D019-like to the quasi-β1 structures.

Aged Mg-3.0 wt% Nd alloys were investigated by high angle annular dark-field scanning transmission electron microscopy. A hitherto unreported metastable phase designated β 3 can always emerge at the endpoints of β 1 particles. The crystal structure of β 3 phase is determined to an orthorhombic lattice (space group Cmcm ). With the {111} β 1 planes acting as the basal plane of growth, β 3 phase has three types of variants, which are related by a 120° rotation with respect to each other around the same [001] β 3 axis. In addition, several peculiar morphologies and further evolution of β 3 phase were also analyzed.

After solid solution and aging treatment, Mg–3.0 wt%Y–1.0 wt%Ce ternary alloys were characterized using high angle annular dark field scanning transmission electron microscopy. The main precipitates are dominated by β′ phase and Mg17Ce2, a Ni17Th2–type intermetallic compound. An orientation domain can be discerned generally in Mg17Ce2 granules. This domain structure of Mg17Ce2 always consists of two types of domains (defined as domain–Ι and domain–Π) with a 90 degree orientation difference. In terms of crystallographic orientation relationships among α-Mg matrix and both domains, the domain–Ι is parallel to α-Mg matrix, whereas, the domain–Π is perpendicular to α-Mg matrix. It can be certain that a 1 ¯ 010 direction is an unchanged orientation. Due to nearly equal values of lattice parameters (a and c) of Mg17Ce2, both domain–Ι and domain–Π can matches well with α-Mg matrix. Comparatively, the interfacial matching between domain–Ι and α-Mg matrix is better, suggesting that the domain–Ι is dominant.

Polycrystalline lanthanum-doped (Bi 1- x La x ) 2 Sr 2 CaCu 2 O 8+ δ samples for x = 0, 0.03, 0.05, 0.08, 0.10, 0.15 and 0.20, were synthesized by the Sol-Gel method. The Bi-2212 phase was structurally characterized by X-ray diffraction (XRD), Rietveld refinement and transmission electron microscopy (TEM). In the whole doping ranges, it can be proved that the dominated Bi-2212 phase crystallizes in a tetragonal structure with space group I 4/mmm and the doping element La has been incorporated partly into the Bi-2212 lattices. With increasing x , a and c axes of Bi-2212 lattice shrink gradually when x ≤ 0.05, which mainly is ascribed to the role of the stronger La O bonding. Afterwards, the larger ionic radius of La 3+ will play a decisive role in the elongation of a and c axes. Meanwhile, the substitution of La 3+ for Bi 3+ causes the evolution of the altitude of the CuO 5 pentahedra.

In Mg−0.8 at.% Bi binary alloys,the structure, the morphology and the orientation of precipitates were characterized by high-resolution transmission electron microscopy (HRTEM) and high-angle annular dark detector field scanning transmission electron microscopy (HAADF−STEM) techniques. The main precipitate is the α-Mg3Bi2 phase with hexagonal structure ( P 3 ¯ m 1 ). The morphology of α-Mg3Bi2 precipitate is classified into three types, rod-shaped, cuboid-shaped and polyhedral, which are related closely with orientation relationships (ORs) between α-Mg3Bi2 precipitate and α Mg matrix. For the first two types of morphologies, precipitate and α Mg matrix can maintain the following ORs: 11 2 ¯ 0 Mg 3 Bi 2 / / 0001 Mg and 1 1 ¯ 00 Mg 3 Bi 2 / / 1 1 ¯ 00 Mg . In contrast, another set of ORs between polyhedral α-Mg3Bi2 and α Mg matrix can be determined as: 11 2 ¯ 0 Mg 3 Bi 2 / / 11 2 ¯ 0 Mg and 0003 Mg 3 Bi 2 / / 1 1 ¯ 01 Mg . The morphology of α-Mg3Bi2 precipitates is discussed particularly based on the interfacial misfit mechanism.

Increasing evidence supports a role for N-myc downstream-regulated gene 2 (NDRG2) deregulation in tumorigenesis. We investigated the roles and mechanisms of NDRG2 in human cholangiocarcinoma (CCA) progression. In the present study, expression of NDRG2, microRNA (miR)-181c and leukemia inhibitory factor (LIF) in human CCA and adjacent nontumor tissues were examined. The effects of NDRG2 on CCA tumor growth and metastasis were determined both in vivo and in vitro. The role of the NDRG2/LIF/miR-181c signaling pathway in cholangiocarcinogenesis and metastasis were investigated both in vivo and in vitro. The results showed that human CCA tissues exhibited decreased levels of NDRG2 and increased levels of miR-181c and LIF compared with nontumor tissues. NDRG2 could inhibit CCA cell proliferation, chemoresistance, and metastasis both in vitro and in vivo. We found that NDRG2 is a target gene of miR-181c, and the down-regulation of NDRG2 was attributed to miR-181c overexpression in CCA. Furthermore, miR-181c can be activated by LIF treatment, whereas NDRG2 could inhibit LIF transcription through disrupting the binding between Smad, small mothers against decapentaplegic complex and LIF promoter. Down-regulation of NDRG2 and overexpression of miR-181c or LIF are significantly associated with a poorer overall survival (OS) in CCA patients. Finally, we found that a combination of NDRG2, miR-181c, and LIF expression is a strong predictor of prognosis in CCA patients. Conclusion: These results establish the counteraction between NDRG2 and LIF/miR-181c as a key mechanism that regulates cholangiocarcinogenesis and metastasis. Our results elucidated a novel pathway in NDRG2-mediated inhibition of cholangiocarcinogenesis and metastasis and suggest new therapeutic targets, including NDRG2, LIF, miR-181c, and transforming growth factor beta, in CCA prevention and treatment. (Hepatology 2016;64:1606-1622)

Hepatocellular carcinoma (HCC) is a highly vascularized tumor with frequent extrahepatic metastasis. Active angiogenesis and metastasis are responsible for rapid recurrence and poor survival of HCC. However, the mechanisms that contribute to tumor metastasis remain unclear. Here we evaluate the effects of ATPase inhibitory factor 1 (IF1), an inhibitor of the mitochondrial H(+)-adenosine triphosphate (ATP) synthase, on HCC angiogenesis and metastasis. We found that increased expression of IF1 in human HCC predicts poor survival and disease recurrence after surgery. Patients with HCC who have large tumors, with vascular invasion and metastasis, expressed high levels of IF1. Invasive tumors overexpressing IF1 were featured by active epithelial-mesenchymal transition (EMT) and increased angiogenesis, whereas silencing IF1 expression attenuated EMT and invasion of HCC cells. Mechanistically, IF1 promoted Snai1 and vascular endothelial growth factor (VEGF) expression by way of activating nuclear factor kappa B (NF-κB) signaling, which depended on the binding of tumor necrosis factor (TNF) receptor-associated factor 1 (TRAF1) to NF-κB-inducing kinase (NIK) and the disruption of NIK association with the TRAF2-cIAP2 complex. Suppression of the NF-κB pathway interfered with IF1-mediated EMT and invasion. Chromatin immunoprecipitation assay showed that NF-κB can bind to the Snai1 promoter and trigger its transcription. IF1 was directly transcribed by NF-κB, thus forming a positive feedback signaling loop. There was a significant correlation between IF1 expression and pp65 levels in a cohort of HCC biopsies, and the combination of these two parameters was a more powerful predictor of poor prognosis. Conclusion: IF1 promotes HCC angiogenesis and metastasis by up-regulation of Snai1 and VEGF transcription, thereby providing new insight into HCC progression and IF1 function. (Hepatology 2014;60:1659–1673)

Although gankyrin is involved in the tumorigenicity and metastasis of some malignancies, the role of gankyrin in cholangiocarcinoma (CCA) is unclear. In this study we investigated the expression of gankyrin in human CCA tissues and cell lines. The effects of gankyrin on CCA tumor growth and metastasis were determined both in vivo and in vitro. The results showed that gankyrin was overexpressed in CCA tissues and cell lines. Gankyrin expression was associated with CCA histological differentiation, TNM stage, and metastasis. The multivariate Cox analysis revealed that gankyrin was an independent prognostic indicator for overall survival. Gankyrin overexpression promoted CCA cell proliferation, migration, and invasion, while gankyrin knockdown inhibited CCA tumor growth, metastasis, and induced Rb-dependent senescence and G1 phase cell cycle arrest. Gankyrin increased the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and promoted the nuclear translocation of p-STAT3. Suppression of STAT3 signaling by small interfering RNA (siRNA) or STAT3 inhibitor interfered with gankyrin-mediated carcinogenesis and metastasis, while interleukin (IL)-6, a known upstream activator of STAT3, could restore the proliferation and migration of gankyrin-silenced CCA cells. The IL-6 level was decreased by gankyrin knockdown, while increased by gankyrin overexpression. Gankyrin regulated IL-6 expression by way of facilitating the phosphorylation of Rb; meanwhile, rIL-6 treatment increased the expression of gankyrin, suggesting that IL-6 was regulated by a positive feedback loop involving gankyrin in CCA. In the xenograft experiments, gankyrin overexpression accelerated tumor formation and increased tumor weight, whereas gankyrin knockdown showed the opposite effects. The in vivo spontaneous metastasis assay revealed that gankyrin promoted CCA metastasis through IL-6/STAT3 signaling pathway. Conclusion: Gankyrin is crucial for CCA carcinogenesis and metastasis by activating IL-6/STAT3 signaling pathway through down-regulating Rb protein. (Hepatology 2014;59:935–946)

Glutamate is the major mediator of excitotoxic neuronal death following cerebral ischemia. Under severe ischemic conditions, glutamate transporters can functionally reverse to release glutamate, thereby inducing further neuronal injury. Hypothermia has been shown to protect neurons from brain ischemia. However, the mechanism(s) involved remain unclear. Therefore, the aim of this study was to investigate the mechanism(s) mediating glutamate release during brain ischemia-reperfusion injury under hypothermic conditions. Neuron/astrocyte co-cultures were exposed to oxygen-glucose deprivation (OGD) at various temperatures for 2h, and cell viability was assayed 12h after reoxygenation. PI and MAP-2 staining demonstrated that hypothermia significantly decreased neuronal injury. Furthermore, [(3)H]-glutamate uptake assays showed that hypothermia protected rat primary cortical cultures against OGD reoxygenation-induced injury. Protein levels of the astrocytic glutamate transporter, GLT-1, which is primarily responsible for the clearance of extracellular glutamate, were also found to be reduced in a temperature-dependent manner. In contrast, expression of GLT-1 in astrocyte-enriched cultures was found to significantly increase following the addition of neuron-conditioned medium maintained at 37 °C, and to a lesser extent with neuron-conditioned medium at 33 °C. In conclusion, the neuroprotective effects of hypothermia against brain ischemia-reperfusion injury involve down-regulation of astrocytic GLT-1, which mediates the reverse transport of glutamate. Moreover, this process may be regulated by molecules secreted by stressed neurons.

Summary Mesenchymal stem cells (MSCs) have the ability to suppress T cell proliferation and modulate cytokine production. Recently, MSCs have been shown to ameliorate autoimmune diseases such as experimental autoimmune encephalomyelitis (EAE), but in some cases shown to stimulate lymphocyte proliferation. So far, mechanisms through which MSCs modulate immune reactions are still undefined. In this report we demonstrate that MSCs have the capacity for either stimulating or inhibiting myelin basic protein-specific T lymphocytes in a dose-dependent manner and modulate antigen-stimulated T cells to differentiate into either T helper type 17 or regulatory T cells, respectively, via pathways involving transforming growth factor-β and interleukin-6. These results may lead better utility of MSCs as a treatment for autoimmune disease.

Increasing evidence supports a role for N-myc downstream-regulated gene 2 (NDRG2) deregulation in tumorigenesis. We investigated the roles and mechanisms of NDRG2 in human cholangiocarcinoma (CCA) progression. In the present study, expression of NDRG2, microRNA (miR)-181c and leukemia inhibitory factor (LIF) in human CCA and adjacent nontumor tissues were examined. The effects of NDRG2 on CCA tumor growth and metastasis were determined both in vivo and in vitro. The role of the NDRG2/LIF/miR-181c signaling pathway in cholangiocarcinogenesis and metastasis were investigated both in vivo and in vitro. The results showed that human CCA tissues exhibited decreased levels of NDRG2 and increased levels of miR-181c and LIF compared with nontumor tissues. NDRG2 could inhibit CCA cell proliferation, chemoresistance, and metastasis both in vitro and in vivo. We found that NDRG2 is a target gene of miR-181c, and the down-regulation of NDRG2 was attributed to miR-181c overexpression in CCA. Furthermore, miR-181c can be activated by LIF treatment, whereas NDRG2 could inhibit LIF transcription through disrupting the binding between Smad, small mothers against decapentaplegic complex and LIF promoter. Down-regulation of NDRG2 and overexpression of miR-181c or LIF are significantly associated with a poorer overall survival (OS) in CCA patients. Finally, we found that a combination of NDRG2, miR-181c, and LIF expression is a strong predictor of prognosis in CCA patients.These results establish the counteraction between NDRG2 and LIF/miR-181c as a key mechanism that regulates cholangiocarcinogenesis and metastasis. Our results elucidated a novel pathway in NDRG2-mediated inhibition of cholangiocarcinogenesis and metastasis and suggest new therapeutic targets, including NDRG2, LIF, miR-181c, and transforming growth factor beta, in CCA prevention and treatment. (Hepatology 2016;64:1606-1622).

Associating Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) has been reported to be a novel surgical technique that provides fast and effective growth of liver remnant. Despite occasional reports on animal studies, the mechanisms of rapid liver regeneration in ALPPS remains unclear. In the present study, we intend to develop a reproducible rat model to mimick ALPPS and to explore the underlying mechanisms. Rats assigned to the portal vein ligation (PVL), left lateral lobe (LLL) resection, transection and sham groups served as controls. Results indicated that the regeneration rate in the remnant liver after ALPPS was two times relative to PVL, whereas rats with transection alone showed minimal volume increase. The expression levels of Ki-67 and PCNA were about ten-fold higher after ALPPS compared with the transection and LLL resection groups and four-fold higher compared with the PVL group. The levels of TNF-α, IL-6 and HGF in the regenerating liver remnant were about three-fold higher after ALPPS than the controls. There was a more significant activation of NF-κB p65, STAT3 and Yap after ALPPS, suggesting synergistic activation of the pathways by PVL and transection, which might play an important role in liver regeneration after ALPPS.