A near-infrared photodetector based on carbon nanotube transistors exhibits ultra-low dark current through field-modulated charge carrier transport.

Near-infrared photodetectors (NIR PDs) are devices that convert infrared light signals, which are widely used in military and civilian applications, into electrical signals. However, a common problem associated with PDs is a high dark current. Interestingly, gate voltage can regulate carrier migration in the channels. In this study, a PbS quantum dot heterojunction combined with a carbon nanotube (CNT) field effect transistor (FET) is designed and described. Significantly, this NIR PD achieves field-modulated carrier transport in a CNT transistor, in which the dark current is effectively regulated by the gate voltage. In this PD, an ultra-low dark current of 8 pA is obtained by gate voltage regulation. Moreover, the device shows a fast response speed of 6.5 ms and a high normalized detectivity of 4.75 × 1011 Jones at 0.085 W cm-2 power density and -0.2 V bias voltage. Overall, this work details a novel strategy for the fabrication of a PD with an ultra-low dark current based on a FET.

Association of clinical characteristics and recurrence of conventional colorectal adenomas with patient age: a single-center study.

OBJECTIVES: We performed a clinical study comparing early-onset and late-onset conventional colorectal adenomas (CCRAs) since little is known about the differences in their characteristics. METHODS: Pearson's chi-square test and the Kruskal‒Wallis test were used to compare basic information. MCAR tests and multiple imputation were performed to complete missing values. Multivariate logistic analysis and propensity score matching were used to identify the risk factors for recurrence. RESULTS: We included 2793 patients (688 with early-onset CCRAs and 2105 with late-onset CCRAs) from January 2017 to December 2021. Patients with early-onset CCRAs had higher levels of Hb, ALB, and triglycerides but lower HDL levels and N/L ratios. Moreover, we found that more early-onset CCRAs were in the left colon than late-onset CCRAs, and the size of early-onset CCRAs was larger. Early-onset CCRAs tended to lack pedicles compared to late-onset CCRAs. Additionally, the ratio of EMR and APC in early-onset CCRAs was higher than that in late-onset CCRAs, and the ratio of ESD and surgery for late-onset CCRAs was higher. We found that age ≥ 50 years, abnormal vessels, drinking alcohol, and DB and ALB levels may be risk factors for recurrence, while the LDL level may be a protective factor. Finally, analysis of cumulative recurrence rates after PSM showed that patients with late-onset CCRAs exhibited higher recurrence rates (P < 0.05). CONCLUSION: Compared with late-onset CCRAs, early-onset CCRAs were associated with higher triglyceride levels, lower HDL levels, and larger tumor volumes. Age ≥ 50 years, abnormal vessels, alcohol consumption, and DB and ALB levels were independent risk factors for recurrence of CCRAs.

Low expression of FOXP2 predicts poor survival and targets caspase-1 to inhibit cell pyroptosis in colorectal cancer.

Background: Colorectal cancer (CRC) is the third most common cancer worldwide. Several studies have suggested that FOXP2 functions as a tumour suppressor. However, to date, it remains unclear how FOXP2 influences CRC occurrence. Methods: We took advantage of CRC tissue samples and compared the expression of FOXP2 via immunohistochemistry assays. We elucidated the underlying function of FOXP2 in CRC cells by constructing a cell model with FOXP2 depletion. Co-IP experiments and immunofluorescence (IF) assays were conducted, and the results demonstrated that FOXP2 can promote the activation of caspase-1 to enhance cell pyroptosis. Results: We used tissue RNA sequencing analysis in a colitis-associated cancer mouse model, and found that FOXP2 was downregulated in colitis and tumour tissues. We also found that CRC patients with low FOXP2 expression had poorer survival. Cell viability assays and electron microscopic examination showed that depletion of FOXP2 could enhance cell growth and inhibit cell pyroptosis. At the same time, knocking down FOXP2 expression was able to promote the protein expression of PCNA and cyclin D1 and downregulate the expression of the caspase family of proteins and GSDMD, which are markers of pyroptosis. A series of co-IP and IF assays revealed that FOXP2 interacts with caspase-1 and promotes its expression. Conclusion: Our findings reveal a key role for FOXP2 in CRC cell pyroptosis and provide a mechanism explaining how FOXP2 promotes cell pyroptosis.