LncRNA FIRRE stimulates PTBP1-induced Smurf2 decay, stabilizes B-cell receptor, and promotes the development of diffuse large B-cell lymphoma.

Sustained expression of B-cell receptor (BCR) critically contributes to the development of diffuse large B-cell lymphoma (DLBCL). However, little is known on the mechanism regulating BCR expression. In the present study, we explored the biological significance of functional intergenic repeating RNA element (FIRRE) in DLBCL and its regulation on BCR. Functional impacts of FIRRE on cell viability, transformation, and apoptosis were examined by MTT, colony formation, and flow cytometry, respectively. The interaction between FIRRE and polypyrimidine tract binding protein 1 (PTBP1) was identified by RNA pull-down and verified using RNA immunoprecipitation (RIP) assays. The effects of FIRRE and PTBP1 on Smurf2 mRNA were examined by RIP, RNA pull-down, and mRNA stability assays. Smurf2-mediated BCR ubiquitination was investigated using co-immunoprecipitation, ubiquitination, and protein stability assays. In vivo, xenograft models were used to assess the impacts of targeting FIRRE on DLBCL growth. FIRRE was specifically up-regulated in and essentially maintained multiple malignant behaviors of BCR-dependent DLBCL cells. Through the interaction with PTBP1, FIRRE promoted the mRNA decay of Smurf2, a ubiquitin ligase for the degradation BCR protein. Targeting FIRRE was sufficient to regulat Smurf2 and BCR expressions and inhibit DLBCL malignancy both in vivo and in vitro. FIRRE-PTBP1 interaction, by simulating Smurf2 mRNA decay and stabilizing BCR, promotes the development of DLBCL. Consequently, targeting this signaling mechanism may provide therapeutic benefits for DLBCL.

Image-free real-time target tracking by single-pixel detection.

Image-based target tracking methods rely on continuous image acquisition and post-processing, which will result in low tracking efficiency. To realize real-time tracking of fast moving objects, we propose an image-free target tracking scheme based on the discrete cosine transform and single-pixel detection. Our method avoids calculating all the phase values, so the number of samples can be greatly reduced. Furthermore, complementary modulation is applied to reduce the measurement noise, and background subtraction is applied to enhance the contrast. The results of simulations and experiments demonstrate that the proposed scheme can accomplish the tracking task in a complex background with a sampling ratio of less than 0.59% of the Nyquist-Shannon criterion, thereby significantly reducing the measurement time. The tracking speed can reach 208 fps at a spatial resolution of 128 × 128 pixels with a tracking error of no more than one pixel. This technique provides a new idea for real-time tracking of fast-moving targets.

Clinical significance of measuring reticulated platelets in infectious diseases.

This study aimed to explore the association between the percentage of reticulated platelets (RP%) and infection, and analyze the value of combined measurement of RP% with other inflammatory indicators in diagnosing infection. A total of 190 patients with signs and symptoms suspicious of infection were included in the infection group, and 70 healthy subjects with comparable percentages of gender and age were included in the control group. Peripheral white blood cell (WBC) count, percentage of neutrophils (N%), platelet count, C-reactive protein (CRP), procalcitonin (PCT), RP%, and axillary temperature were recorded. Dynamic changes in RP% with infection were measured to analyze the association between RP% and infection. The receiver operating characteristic curve was used to evaluate the value of each inflammatory indicator in diagnosing infection and analyze the diagnostic value of the combined adoption of multiple inflammatory indicators. RP% was significantly higher in the infection group than in the noninfection and control groups. The sensitivity and specificity for diagnosing infection were, respectively, 91.78% and 93.18% when RP% and CRP were used in combination, 90.41% and 90.90% when RP% and PCT were used in combination, and 100% and 100% when RP%, CRP, and PCT were used in combination. RP% changed dynamically with the progression of infection and recovered to lower than 5.5% at 2 to 7 days before the body temperature recovered to a normal level. The diagnostic value of RP% was the highest. A combined use with CRP/PCT could improve the sensitivity and specificity in the early diagnosis of infectious diseases.