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Objective: To assess the overall effectiveness of non-pharmacological interventions on internet addiction (IA) in youth. Method: Randomized controlled trials (RCTs) published from their inception to April 1, 2023 were searched in Cochrane, Embase, Medline, Web of Science, China National Knowledge Infrastructure, China Science and Technology Journal Database, Chinese BioMedical Literature Database, and WanFang Data. Two reviewers independently extracted data and evaluated bias using the Cochrane Risk of Bias tool. Results: Sixty-six studies performed from 2007 to 2023, with a total of 4,385 participants, were identified. The NPIs included group counseling, cognitive behavioral therapy, sports intervention, combined interventions, eHealth, educational intervention, positive psychology intervention, sand play intervention, and electrotherapy. The results revealed that NPIs significantly reduced IA levels (standardized mean difference, SMD: -2.01, 95% confidence interval, CI: -2.29 to -1.73, I2 = 93.0%), anxiety levels (SMD: -1.07, 95%CI: -1.41 to -0.73, I2 = 72.4%), depression levels (SMD: -1.11, 95%CI: -1.52 to -0.7, I2 = 84.3%), and SCL-90 (SMD: -0.75, 95%CI: -0.97 to -0.54, I2 = 27.7%). Subgroup analysis stratified by intervention measure showed that cognitive behavioral therapy, group counseling, sports intervention, combined intervention, educational intervention, positive psychology intervention, sandplay intervention, and mobile health were all effective in relieving symptoms of IA except electrotherapy. Conclusion: NPIs appear to be effective in the treatment of IA in youth, which would act as an alternative treatment of IA. Further studies with larger sample sizes and robust designs are needed.
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The ability of Streptococcus mutans to survive and cause dental caries is dependent on its ability to metabolize various carbohydrates, accompanied by extracellular polysaccharide synthesis and biofilm formation. Here, the role of an rel competence-related regulator (RcrR) in the regulation of multiple sugar transportation and biofilm formation is reported. The deletion of the rcrR gene in S. mutans caused delayed growth, decreased biofilm formation ability, and affected the expression level of its multiple sugar transportation-related genes. Transcriptional profiling revealed 17 differentially expressed genes in the rcrR mutant. Five were downregulated and clustered with the sugar phosphotransferase (PTS) systems (mannitol- and trehalose-specific PTS systems). The conserved sites bound by the rcrR promoter were then determined by electrophoretic mobility shift assays (EMSAs) and DNase I footprinting assays. Furthermore, a potential binding motif in the promoters of the two PTS operons was predicted using MEME Suite 5.1.1. RcrR could bind to the promoter regions of the two operons in vitro, and the sugar transporter-related genes of the two operons were upregulated in an rcrR-overexpressing strain. In addition, when RcrR-binding sites were deleted, the growth rates and final yield of S. mutans were significantly decreased in tryptone-vitamin (TV) medium supplemented with different sugars, but not in absolute TV medium. These results revealed that RcrR acted as a transcription activator to regulate the two PTS systems, accompanied by multiple sugar transportation and biofilm formation. Collectively, these results indicate that RcrR is a critical transcription factor in S. mutans that regulates bacterial growth, biofilm formation, and multiple sugar transportation. IMPORTANCE The human oral cavity is a constantly changing environment. Tooth decay is a commonly prevalent chronic disease mainly caused by the cariogenic bacterium Streptococcus mutans. S. mutans is an oral pathogen that metabolizes various carbohydrates into extracellular polysaccharides (EPSs), biofilm, and tooth-destroying lactic acid. The host diet strongly influences the availability of multiple carbohydrates. Here, we showed that the RcrR transcription regulator plays a significant role in the regulation of biofilm formation and multiple sugar transportation. Further systematic evaluation of how RcrR regulates the transportation of various sugars and biofilm formation was also conducted. Notably, this study decrypts the physiological functions of RcrR as a potential target for the better prevention of dental caries.
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INTRODUCTION: Despite the strong appeal of ferritin as a magnetic resonance imaging (MRI) reporter for stem cell research, no attempts have been made to apply this genetic imaging reporter in stem cells in an inducible manner, which is important for minimizing the potential risk related to the constitutive expression of an imaging reporter. The aim of the present study was to develop an inducible genetic MRI reporter system that enables the production of intracellular MRI contrast as needed. METHODS: Ferritin heavy chain (FTH1) was genetically modified by adding a Tet-On switch. A C3H10T1/2 cell line carrying Tet-FTH1 (C3H10T1/2-FTH1) was established via lentiviral transduction. The dose- and time-dependent expression of FTH1 in C3H10T1/2 cells was assessed by western blot and immunofluorescence staining. The induced "ON" and non-induced "OFF" expressions of FTH1 were detected using a 3.0 T MRI scanner. Iron accumulation in cells was analyzed by Prussian blue staining and transmission electron microscopy (TEM). RESULTS: The expression of FTH1 was both dose- and time-dependently induced, and FTH1 expression peaked in response to induction with doxycycline (Dox) at 0.2 µg/ml for 72 h. The induced expression of FTH1 resulted in a significant increase in the transverse relaxation rate of C3H10T1/2-FTH1 cells following iron supplementation. Prussian blue staining and TEM revealed extensive iron accumulation in C3H10T1/2-FTH1 cells in the presence of Dox. CONCLUSIONS: Cellular MRI contrast can be produced as needed via the expression of FTH1 under the control of a Tet-On switch. This finding could lay the groundwork for the use of FTH1 to track stem cells in vivo in an inducible manner.