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Thousands of resting state functional magnetic resonance imaging (RS-fMRI) articles have been published on brain disorders. For precise localization of abnormal brain activity, a voxel-level comparison is needed. Because of the large number of voxels in the brain, multiple comparison correction (MCC) must be performed to reduce false positive rates, and a smaller P value (usually including either liberal or stringent MCC) is widely recommended. The study suggests that a stringent MCC may reduce the number of false positive results and that the brain regions surviving MCC are true positive results and thus can improve the reproducibility between studies. However, determining the clusters that represent true positives is difficult because ground truths have not been established for many brain disorders that do not present visible structural abnormalities, e.g., Parkinson's disease (PD) and many psychiatric disorders. Meta-analysis provides robust results that can be used to investigate reproducibility across studies. However, most existing neuroimaging meta-analytic articles are based on only a few peak coordinates reported in the original articles, namely coordinate-based meta-analysis (CB-meta). The current REST-meta-PD study included raw RS-fMRI data from 15 cohorts of PD patients and performed a meta-analysis of the amplitude of low frequency fluctuations (ALFF). We used the robustness results of the meta-analysis to test whether liberal or stringent MCC could increase reproducibility and reduce false positive rates.

Objective CareHPV is a human papillomavirus (HPV) DNA test for low-resource settings (LRS). This study assesses optimum triage strategies for careHPV-positive women in LRS. Methods A total of 2,530 Chinese women were concurrently screened for cervical cancer with visual inspection with acetic acid (VIA), liquid-based cytology and HPV testing by physician- and self-collected careHPV, and physician-collected Hybrid Capture 2 (HC2). Screen-positive women were referred to colposcopy with biopsy and endocervical curettage as necessary. HPV-positivity was defined as ≥1.0 relative light units/cutoff (RLU/CO) for both careHPV and HC2. Primary physician-HC2, physician-careHPV and self-careHPV and in sequential screening with cytology, VIA, or increased HPV test-positivity performance, stratified by age, were assessed for cervical intraepithelial neoplasia (CIN) grade 2/3 or worse (CIN2/3+) detection. Results The sensitivities and specificities of primary HPV testing for CIN2+ were: 83.8%, 88.1% for physician-careHPV; 72.1%, 88.2% for self-careHPV; and 97.1%, 86.0% for HC2. Physician-careHPV test-positive women with VIA triage had a sensitivity of 30.9% for CIN2+ versus 80.9% with cytology triage. Self-careHPV test-positive women with VIA triage was 26.5% versus 66.2% with cytology triage. The sensitivity of HC2 test-positive women with VIA triage was 38.2% versus 92.6% with cytology triage. The sensitivity of physician-careHPV testing for CIN2+ decreased from 83.8% at ≥1.0 RLU/CO to 72.1% at ≥10.00 RLU/CO, while the sensitivity of self-careHPV testing decreased from 72.1% at ≥1.0 RLU/CO to 32.4% at ≥10.00 RLU/CO; similar trends were seen with age-stratification. Conclusions VIA and cytology triage improved specificity for CIN2/3 than no triage. Sensitivity with VIA triage was unsuitable for a mass-screening program. VIA provider training might improve this strategy. Cytology triage could be feasible where a high-quality cytology program exists. Triage of HPV test-positive women by increased test positivity cutoff adds another LRS triage option.

Thousands of papers using resting-state functional magnetic resonance imaging (RS-fMRI) have been published on brain disorders. Results in each paper may have survived correction for multiple comparison. However, since there have been no robust results from large scale meta-analysis, we do not know how many of published results are truly positives. The present meta-analytic work included 60 original studies, with 57 studies (4 datasets, 2266 participants) that used a between-group design and 3 studies (1 dataset, 107 participants) that employed a within-group design. To evaluate the effect size of brain disorders, a very large neuroimaging dataset ranging from neurological to psychiatric isorders together with healthy individuals have been analyzed. Parkinson’s disease off levodopa (PD-off) included 687 participants from 15 studies. PD on levodopa (PD-on) included 261 participants from 9 studies. Autism spectrum disorder (ASD) included 958 participants from 27 studies. The meta-analyses of a metric named amplitude of low frequency fluctuation (ALFF) showed that the effect size (Hedges’ g) was 0.19 - 0.39 for the 4 datasets using between-group design and 0.46 for the dataset using within-group design. The effect size of PD-off, PD-on and ASD were 0.23, 0.39, and 0.19, respectively. Using the meta-analysis results as the robust results, the between-group design results of each study showed high false negative rates (median 99%), high false discovery rates (median 86%), and low accuracy (median 1%), regardless of whether stringent or liberal multiple comparison correction was used. The findings were similar for 4 RS-fMRI metrics including ALFF, regional homogeneity, and degree centrality, as well as for another widely used RS-fMRI metric namely seed-based functional connectivity. These observations suggest that multiple comparison correction does not control for false discoveries across multiple studies when the effect sizes are relatively small. Meta-analysis on un-thresholded t-maps is critical for the recovery of ground truth. We recommend that to achieve high reproducibility through meta-analysis, the neuroimaging research field should share raw data or, at minimum, provide un-thresholded statistical images.

TTRAP is a multi-functional protein that is involved in multiple aspects of cellular functions including cell proliferation, apoptosis and the repair of DNA damage. Here, we demonstrated that the lentivirus-mediated overexpression of TTRAP significantly inhibited cell growth and induced apoptosis in osteosarcoma cells. The ectopic TTRAP suppressed the growth and colony formation capacity of two osteosarcoma cell lines, U2OS and Saos-2. Cell apoptosis was induced in U2OS cells and the cell cycle was arrested at G2/M phase in Saos-2 cells. Exogenous expression of TTRAP in serum-starved U2OS and Saos-2 cells induced an increase in caspase-3/-7 activity and a decrease in cyclin B1 expression. In comparison with wild-type TTRAP, mutations in the 5'-tyrosyl-DNA phosphodiesterase activity of TTRAP, in particular TTRAPE152A, showed decreased inhibitory activity on cell growth. These results may aid in clarifying the physiological functions of TTRAP, especially its roles in the regulation of cell growth and tumorigenesis. [BMB Reports 2013; 46(2): 113-118]

To establish a 96-well plate based kinase assay using a recombinant vascular endothelial growth factor (VEGF) receptor 1 kinase domain protein.A human VEGF receptor 1 kinase domain protein was expressed in E coli, and its activity was monitored by its ability of phosphorylating the polyE4Y substrate coated on the walls of 96-well plates with antibody recognition and a colorimetric readout. A random screening of a sample organic compound library was carried out, and the hits were characterized with a transformed cell line stably expressing VEGF receptor 1 protein.An efficient E coli expression system for human VEGF receptor 1 kinase domain protein was constructed, and the purified recombinant protein was used to establish a practical screening assay for kinase inhibitors in vitro. Two thousand eight hundred organic compounds were screened, and two disubstituted furans (A1 and A5) with new structure showed inhibition of VEGF receptor 1 kinase. Compound A1 inhibited only phosphorylation of substrate, while compound A5 inhibited both autophosphorylation and substrate phosphorylation. Both inhibitors affected phosphorylation in the transformed cells.The recombinant receptor kinase based assay is simple and effective in identifying kinase inhibitors.