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In order to develop a near-infrared band fiber grating external cavity semiconductor laser for quantum precision measurement applications, a high polarization dependent gain chip and a birefringent fiber Bragg grating were designed independently, the effects of grating reflectivity, external cavity, and chip length on laser linewidth were systematically analyzed based on the Fabry-Pérot equivalent resonant cavity model. The results shows that the developed laser achieves an output power of 54.46 mW, a side mode suppression ratio of 58.88 dB, and a polarization extinction ratio of 24.46 dB. The Lorentz linewidth measured is 2.69 kHz by delayed self-heterodyne beat frequency method. This study provides a reference for the single frequency narrow linewidth external cavity semiconductor lasers with independent design and preparation of discrete devices, and is expected to be used in quantum precision measurement fields such as radar imaging, gyroscopes, magnetometers, and atomic clocks. [ABSTRACT FROM AUTHOR]

Background: Human papillomavirus (HPV) infection has become an important etiological driver of oropharyngeal squamous cell carcinoma (OPSCC), leading to unique tumor characteristics. However, the interplay between HPV-associated tumor cells and tumor microenvironment (TME) remains an enigma. Methods: We performed a single-cell RNA-sequencing (scRNA-seq) on HPV-positive (HPV+) and HPV-negative (HPV‒) OPSCC tumors, each for three samples, and one normal tonsil tissue. Ex vivo validation assays including immunofluorescence staining, cell line co-culture, and flow cytometry analysis were used to test specific subtypes of HPV+ tumor cells and their communications with T cells. Results: Through a comprehensive single-cell transcriptome analysis, we uncover the distinct transcriptional signatures between HPV+ and HPV‒ OPSCC. Specifically, HPV+ OPSCC tumor cells manifest an enhanced interferon response and elevated expression of the major histocompatibility complex II (MHC-II), potentially bolstering tumor recognition and immune response. Furthermore, we identify a CXCL13+CD4+ T cell subset that exhibits dual features of both follicular and pro-inflammatory helper T cells. Noteworthily, HPV+ OPSCC tumor cells embrace extensive intercellular communications with CXCL13+CD4+ T cells. Interaction with HPV+ OPSCC tumor cells amplifies CXCL13 and IFNγ release in CD4+T cells, fostering a pro-inflammatory TME. Additionally, HPV+ tumor cells expressing high MHC-II and CXCL13+CD4+ T cell prevalence are indicative of favorable overall survival rates in OPSCC patients. Conclusions: Together, our study underscores a synergistic inflammatory immune response orchestrated by highly immunogenic tumor cells and CXCL13+CD4+ T cells in HPV+ OPSCC, offering useful insights into strategy development for patient stratification and effective immunotherapy in OPSCC. [ABSTRACT FROM AUTHOR]

OBJECTIVES Thoracoscopic segmentectomy is the recommended treatment option for small peripheral pulmonary nodules. To assess the ability of preoperative three-dimensional (3D) reconstruction computed tomography (CT) to shorten the operative time and improve perioperative outcomes in thoracoscopic segmentectomy compared with standard chest CT, we conducted this randomized controlled trial. METHODS The DRIVATS study was a multicentre, randomized controlled trial conducted in 3 hospitals between July 2019 and November 2023. Patients with small peripheral pulmonary nodules not reaching segment borders were randomized in a 1:1 ratio to receive either 3D reconstruction CT or standard chest CT before thoracoscopic segmentectomy. The primary end-point was operative time. The secondary end-points included incidence of postoperative complications, intraoperative blood loss and operative accident event. RESULTS A total of 191 patients were enrolled in this study: 95 in the 3D reconstruction CT group and 96 in the standard chest CT group. All patients underwent thoracoscopic segmentectomy except for 1 patient in the standard chest CT group who received a wedge resection. There is no significant difference in operative time between the 3D reconstruction CT group (median, 100 min [interquartile range (IQR), 85–120]) and the standard chest CT group (median, 100 min [IQR, 81–140]) (P  =   0.82). Only 1 intraoperative complication occurred in the standard chest CT group. No significant difference was observed in the incidence of postoperative complications between the 2 groups (P  =   0.52). Other perioperative outcomes were also similar. CONCLUSIONS In patients with small peripheral pulmonary nodules not reaching segment borders, the use of 3D reconstruction CT in thoracoscopic segmentectomy was feasible, but it did not result in significant differences in operative time or perioperative outcomes compared to standard chest CT. [ABSTRACT FROM AUTHOR]

Background The fat mass and obesity-associated protein (FTO) is an RNA demethylase that contributes to several physiological processes. Nonetheless, the impact of FTO on bone remodeling in the midpalatal suture while undergoing rapid maxillary expansion (RME) remains unclear. Methods First, to explore the expression of FTO in the midpalatal suture during RME, six rats were randomly divided into two groups: Expansion group and Sham group (springs without being activated). Then, suture mesenchymal stem cells (SuSCs) were isolated as in vitro model. The expression of FTO was knocked down by small interfering RNA to study the effect of FTO on the osteogenic differentiation of SuSCs. Finally, to evaluate the function of FTO in the process of bone remodeling in the midpalatal suture, ten rats were randomly divided into two groups: FB23-2 group (10 μM, a small molecule inhibitor of FTO) and DMSO group (control). Results Increased arch width and higher expression of OCN and FTO in the midpalatal area were observed in expansion group (P  < .05). In the in vitro model, the mRNA expression levels of Runx2, Bmp2, Col1a1, Spp1, and Tnfrsf11b were decreased (P  < .05) upon knocking down FTO. Additionally, the protein levels of RUNX2 and OPN were also decreased (P  < 0.05). Adding FB23-2, a small-molecule inhibitor targeting FTO, to the medium of SuSCs caused a decrease in the mRNA expression levels of Runx2, Bmp2, Col1a1, Spp1, and Tnfrsf11b (P  < 0.05). There was a statistically significant difference in evaluating the expression of OCN and OPN on the palatal suture between the FB23-2 and DMSO groups (P  < .05). Limitation The molecular mechanisms by which FTO regulates SuSCs osteogenesis remain to be elucidated. The FTO conditional knock out mouse model can be established to further elucidate the role of FTO during RME. Conclusion FTO contributes to the osteogenic differentiation of SuSCs and plays a promoting role in midpalatal suture bone remodeling during the RME. [ABSTRACT FROM AUTHOR]

Objective: Apical periodontitis is the most frequently occurring pathological lesion. Fat mass and obesity‐associated protein (Fto) is the first identified RNA N6‐methyladenosine demethylase. However, whether Fto regulates apical periodontitis remains unclear. This study aimed to explore the mechanisms of Fto in the tumor necrosis factor‐α (TNF‐α)‐induced inflammatory response. Materials and Methods: We established an apical periodontitis model. An immortalized cementoblast cell line (OCCM‐30) cells were exposed to TNF‐α. Fto, Il6, Mcp1, and Mmp9 expressions were assessed by qRT‐PCR. We knocked down Fto using lentiviruses and detected TNF‐α‐induced inflammation‐related gene expressions and mRNA stability. Results: Mice with apical periodontitis showed downregulation of Fto expression. OCCM‐30 cells exposed to TNF‐α showed an upregulation of inflammation‐related genes with a decrease in Fto. Furthermore, knockdown of Fto promoted the expressions of Il6, Mcp1, and Mmp9 in TNF‐α‐treated OCCM‐30 cells as compared with negative control cells, whereas it did not affect the mRNA stability. Interestingly, Fto knockdown activated the p65, p38, and ERK1/2 pathways, and it slightly activated the JNK signaling pathway after TNF‐α administration in OCCM‐30 cells. Conclusion: A TNF‐α‐induced decrease in the expression of Fto might play a critical role in the inflammatory response in cementoblasts, and knockdown of Fto might upregulate the inflammatory response. [ABSTRACT FROM AUTHOR]