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Studies have shown that internet gaming disorder (IGD) has the potential to be a type of addiction; however, direct comparisons (similarities and differences) between IGD and traditional addictions remain scarce, especially at the neuroimaging level. Resting‐state functional magnetic resonance imaging (fMRI) data were collected from 92 individuals with IGD, 96 individuals with tobacco use disorders (TUDs) and 107 individuals who served as healthy controls (HCs). Independent component analysis (ICA) was performed to explore the similarities and differences among these three groups; Granger causality analysis (GCA) was further performed based on the ICA results to determine potential neural features underlying the differences and similarities among the groups. The ICA results indicated significant differences in the subcortical network and cerebellar network. GCA results found that significant differences in bilateral caudate among three groups, and the efferents of dorsal frontostriatal circuit showed significant differences in insula among three groups, whereas efferents of ventral frontostriatal circuit showed significant differences in the medial prefrontal cortex (mPFC). Two kinds of addiction showed differences in thalamus and frontostriatal circuits, and similar changes found in cerebellum and mPFC regions. It suggested that addiction disorders have psychopathology features, and the craving and reward dysfunctions may be the key reasons. Although both substance addiction and behaviour addiction showed craving dysfunction in cerebellum, however, the key reward dysfunction of substance addiction was found in subcortical regions, whereas behaviour addiction located in cortical regions. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the latent Epstein–Barr virus (EBV) infection status of patients with newly diagnosed Hodgkin lymphoma (HL) and to discuss the relationship between tumor cell EBV status and the prognosis of HL patients. A total of 134 previously untreated HL patients were analyzed in the study. Epstein–Barr virus encoded RNAs (EBERs) in situ hybridization was performed to detect the EBV status of tumor cells. EBV positive status correlated with sex (p=0.046) and the proportion of extranodal lesions(p=0.037). There was no obvious correlation between EBV status and overall survival (OS) or failure-free survival (FFS) in all cases, but in cases over 50 years old, EBV positive group had an inferior 5-year FFS compared with EBV negative group (38.5%±13.5% vs 90.9%±8.7%, p=0.012). In FFS multivariate analysis of this age subgroup, EBV positive status was associated with significantly inferior survival (HR, 10.10; 95% CI, 1.26–81.08; p=0.030). This study demonstrates positive tumor cell EBV status is an unfavorable prognostic factor in elder HL patients. [ABSTRACT FROM AUTHOR]

The effects of o-phthalaldehyde (OPTA) on lactate dehydrogenase (LDH) have been studied by following changes in enzymatic activity, aggregation state and conformation. Treatment with OPTA resulted in pseudo first-order inactivation of LDH over a wide concentration range of the inhibitor, and the second-order rate constant was estimated to be 1.52 M−1 s−1. The loss of enzyme activity was concomitant with the increases in absorbance at 337 nm and fluorescence intensity at 405 nm. Complete loss of enzyme activity was accompanied by the formation of approximately 4 mol isoindole derivatives per mole LDH subunit. Cross-linking experiments verified enzyme dissociation during OPTA modification, which could be attributed to the modification of both thiol groups and lysine residues. Circular dichroism (CD) spectra showed that the secondary structure of the OPTA-modified enzyme decreased correspondingly. Comparison of the inactivation with the conformational changes of the enzyme suggests that the active site of the enzyme exhibits greater conformational flexibility than the enzyme molecule as a whole. It is concluded that OPTA modification has multiple effects on LDH, including its inactivation, dissociation and partial unfolding. [Copyright &y& Elsevier]

The inactivation and conformational changes of porcine heart lactate dehydrogenase (LDH) have been studied in sodium dodecyl sulfate (SDS) solutions. Increasing SDS concentration led to a quick and concentration-dependent inhibition of the enzyme, with complete inactivation within 5 min in the presence of 1.0 mM SDS. Meanwhile, fluorescence emission and circular dichroism spectra were used to follow the conformational changes of the enzyme during this process, concurrently showing that SDS less than 1.0 mM induced only limited conformational changes to LDH. The above results are in accordance with the suggestion by Tsou (Trends Biochem. Sci. 11 (1986) 427; Science 262 (1993) 380) that the active site usually be more flexible than the enzyme molecule as a whole. Furthermore, the results of polyacrylamide gel electrophoresis (PAGE) implied that unfolding intermediates were presented in the above process. When the SDS concentration used to treat LDH was increased, the bands of native enzyme on native PAGE faded and finally almost disappeared. Meanwhile, multiple bands with lower mobility but no activity emerged behind and enhanced correspondingly. Fast protein liquid chromatography indicated that dissociation occurred during the course of denaturation. The reasons for the above phenomena have been discussed. It was suggested that SDS, binding to LDH to form different LDH–SDS complexes, conferred an array of different unfolding states over the enzyme, and in turn resulted in the formation of the multiple bands on the native PAGE. [Copyright &y& Elsevier]

The objective of this study was to investigate altered expressions of nuclear matrix proteins (NMPs) of human osteosarcoma (OS) MG-63 cells during curcumin-induced apoptosis of human OS MG-63 cells. MG-63 cells were cultured with curcumin (7.5 mg/L) for 72 hr. Morphological alterations of cells were captured using light microscopy and transmission electron microscopy, and cell cycle distribution was estimated by flow cytometry. NMPs were selectively extracted and subjected to two-dimensional gel electrophoresis (2-DE) analysis. Western blots were performed to determine changes in the expression levels of specific NMPs. The results demonstrated that typical characteristics of apoptosis were observed. Cellular chromatin agglutinated, cell nuclei condensed, and apoptotic bodies were formed after treatment with curcumin. The 2-DE results displayed 27 NMPs, 21 of which were identified to have change in expression levels significantly during apoptosis. The altered expressions of three of these NMPs (nucleophosmin, prohibitin, and vimentin) were further confirmed by immunoblotting. These findings indicated that the apoptosis of MG-63 cells was accompanied by the expression alteration of NMPs. Our results might help to reveal the relationship between NMPs and the regulation of gene expression in the process of apoptosis, as well as provide the basic concepts for future studies on the mechanisms of apoptosis and the therapy for bone diseases.