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Background: The clinical significance of metastasis associated in colon cancer 1 (MACC1), in human gallbladder cancer, is not yet established. This study was performed to assess the expression of MACC1 in benign and malignant gallbladder lesions, and to assess its clinicopathological significance. Materials and Methods: Tissue samples from resected gallbladder cancer (n = 70) and cholelithiasis (n = 70) were evaluated for MACC1 expression by immunohistochemical staining. Their expression was correlated with different clinicopathological parameters. Results: Cytoplasmic MACC1 expression was significantly higher (58.6%) in gallbladder cancer than in chronic cholecystitis (27.1%, P < 0.001). High MACC1 levels were associated with lymph node metastasis (P < 0.05), tumor node metastasis (TNM) stage (P < 0.01), and perineural invasion (P < 0.01), but not with sex, age, history of gallstones or histological grade (P > 0.05). The univariate Kaplan-Meier analysis showed that a positive MACC1 expression was associated with decreased overall survival (P < 0.001). The multivariate Cox regression analysis showed that MACC1 expression and the histopathological subtypes were independent risk factors for disease-free survival. Conclusion: The expression of MACC1 might be closely related to carcinogenesis, clinical biological behaviors, and prognosis of gallbladder adenocarcinoma. [ABSTRACT FROM AUTHOR]

A Claisen rearrangement/iodolactamization sequence starting from commercially available trifluoroacetaldehyde methyl hemiacetal, followed by a classical chemical resolution, provided enantiomerically pure 4,4-difluoro-3,3-dimethylproline (S)-1. No hazardous fluorination reagents were used, and the overall yield over 12 steps was greater than 28%. [ABSTRACT FROM AUTHOR]

The neurotropic parasite Toxoplasma gondii is a globally distributed parasitic protozoan among mammalian hosts, including humans. During the course of infection, the CNS is the most commonly damaged organ among invaded tissues. The polymorphic rhoptry protein 18 (ROP18) is a key serine (Ser)/threonine (Thr) kinase that phosphorylates host proteins to modulate acute virulence. However, the basis of neurotropism and the specific substrates through which ROP18 exerts neuropathogenesis remain unknown. Using mass spectrometry, we performed proteomic analysis of proteins that selectively bind to active ROP18 and identified RTN1-C, an endoplasmic reticulum (ER) protein that is preferentially expressed in the CNS. We demonstrated that ROP18 is associated with the N-terminal portion of RTN1-C and specifically phosphorylates RTN1-C at Ser7/ 134 and Thr4/8/118. ROP18 phosphorylation of RTN1-C triggers ER stress-mediated apoptosis in neural cells. Remarkably, ROP18 phosphorylation of RTN1-C enhances glucose-regulated protein 78 (GRP78) acetylation by attenuating the activity of histone deacetylase (HDAC), and this event is associated with an increase of neural apoptosis. These results clearly demonstrate that both RTN1-C and HDACs are involved in T. gondii ROP18-mediated pathogenesis of encephalitis during Toxoplasma infection. [ABSTRACT FROM AUTHOR]

Remifentanil-induced hyperalgesia (RIH) is a severe but common postoperative clinical problem with elusive underlying neural mechanisms. Here, we discovered that glutamatergic neurons in the thalamic ventral posterolateral nucleus (VPLGlu) exhibited significantly elevated burst firing accompanied by upregulation of Cav3.1 T-type calcium channel expression and function in RIH model mice. In addition, we identified a glutamatergic neuronal thalamocortical circuit in the VPL projecting to hindlimb primary somatosensory cortex glutamatergic neurons (S1HLGlu) that mediated RIH. In vivo calcium imaging and multi-tetrode recordings revealed heightened S1HLGlu neuronal activity during RIH. Moreover, preoperative suppression of Cav3.1-dependent burst firing in VPLGlu neurons or chemogenetic inhibition of VPLGlu neuronal terminals in the S1HL abolished the increased S1HLGlu neuronal excitability while alleviating RIH. Our findings suggest that remifentanil induces postoperative hyperalgesia by upregulating T-type calcium channel-dependent burst firing in VPLGlu neurons to activate S1HLGlu neurons, thus revealing an ion channel-mediated neural circuit basis for RIH that can guide analgesic development. [ABSTRACT FROM AUTHOR]

The obligate intracellular parasite Toxoplasma gondii secretes effector molecules into the host cell to modulate host immunity. Previous studies have shown that T. gondii could interfere with host NF-κB signaling to promote their survival, but the effectors of type I strains remain unclear. The polymorphic rhoptry protein ROP18 is a key serine/threonine kinase that phosphorylates host proteins to modulate acute virulence. Our data demonstrated that the N-terminal portion of ROP18 is associated with the dimerization domain of p65. ROP18 phosphorylates p65 at Ser-468 and targets this protein to the ubiquitin-dependent degradation pathway. The kinase activity of ROP18 is required for p65 degradation and suppresses NF-κB activation. Consistently, compared with wild-type ROP18 strain, ROP18 kinase-deficient type I parasites displayed a severe inability to inhibit NF-κB, culminating in the enhanced production of IL-6, IL-12, and TNF-α in infected macrophages. In addition, studies have shown that transgenic parasites carrying kinase-deficient ROP18 induce M1-biased activation. These results demonstrate for the first time that the virulence factor ROP18 in T. gondii type I strains is responsible for inhibiting the host NF-κB pathway and for suppressing proinflammatory cytokine expression, thus providing a survival advantage to the infectious agent. [ABSTRACT FROM AUTHOR]

In this paper, we developed a novel electrochemical method to quantify DNA methyltransferase (MTase) and analyze DNA MTase activity. After the double DNA helix structure was assembled on the surface of gold nanoparticle modified glassy carbon electrode, it was first methylated by M. SssI MTase and then digested by restriction endonuclease HpaII, which could not recognize the methylated CpG site. Successively, anti-5-methylcytosine antibody was specifically conjugated on the CpG methylation site and horseradish peroxidase labeled goat antimouse IgG (HRP-IgG) was conjugated on anti-5-methylcytosine antibody. In the detection buffer solution containing H2O2 and hydroquinone, HRP-IgG can catalyze hydroquinone oxidation by H2O2 to generate benzoquinone, resulting in a highly electrochemical reduction signal. Consequently, the activity of M. SssI MTase was assayed, and DNA methylation was detected using the signal change with and without methylation. Furthermore, the inhibition investigation demonstrated that, in the presence of 160 μM S-adenosyl-l-methionine as methyl donor, 5-aza-2′-deoxycytidine, procaine, epicatechin, and caffeic acid could inhibit the M. SssI MTase activity with the IC50 values of 45.77, 410.3, 129.03, and 124.2 μM, respectively. Therefore, this study may provide a sensitive platform for screening DNA MTase inhibitors. [ABSTRACT FROM AUTHOR]

Antisense oligonucleotides (ASOs) conjugated to triantennary N-acetyl galactosamine (GalNAc) ligands represent an emerging approach to antisense therapy. Our current generation of GalNAc-ASO conjugates link the GalNAc to the 5'-terminus of the ASO. The conjugation reaction can be accomplished using solution-phase or solid-phase techniques. Here we show a direct comparison of a solution-phase and a solid-phase conjugation strategy. The solution-phase approach, using amine-pentafluorophenyl (PFP) ester coupling, is higher yielding and gives material of slightly higher purity, but requires several additional unit operations and longer production time. The solid-phase approach, using a protected GalNAc ligand phosphoramidite, is more expedient, but results in lower yield and purity. Both strategies efficiently deliver conjugated material in excellent purity. [ABSTRACT FROM AUTHOR]

Resonance Raman spectra (RRs) for 4,5-Ethylenedithio-1,3-dithiole-2-thione (EDDT) were obtained with 397.9 and 416 nm excitation wavelengths, and density functional calculations were performed to elucidate the electronic transitions and the RRs of EDDT in chloroform solvent The RRs indicate that the Franck--Condon region photodynamics have multidimensional character with nuclear motion predominantly along the C4=C5 stretch and the C4=C5 twist out-of-plane. Resonance Raman cross-sections of A-band absorption have been obtained for the vibrational modes of EDDT with its excitation frequencies spanning the 408 nm. Resonance Raman intensity analysis of the resulting RRs excitation profiles and absorption spectrum using a time-dependent wave packet formalism yields mode-specific nuclear displacement and vibrational re-organizational energies. The intensity analysis results for EDDT were compared to previously reported results for dimethyl 1,3-dithioie-2-thione-4,5-dicarboxylate (DDTD), which shows that the additional six-member heterocycle of EDDT strongly affects the reorganizational energy and energy participation. The authors briefly discuss the differences and similarities of the spectra in terms of molecular symmetry and electron density. [ABSTRACT FROM AUTHOR]