Droplet Impedance Feedback-Enabled Microsampling Microfluidic Device for Precise Chemical Information Monitoring.

Microelectrodes have transformed our understanding of spatiotemporal responses to electrical stimulation. However, biological signals are often molecular, complicating the capture of intricate chemical signals. The microfluidic chip developed in this paper accurately measures droplet volume by using impedance analysis. The utilization of droplet volume as a feedback signal for precise microsampling pressure control ensures that microsampling remains unaffected by droplet volume influence. Once the microsampling is complete, chemiluminescence detection enables high temporal resolution and continuous and sensitive monitoring of chemical information within the droplets. Experimental verification shows that the chip can avoid volume influence through impedance feedback, achieving consistent and stable microampling at the nanoliter level (0-3 nL). In just 0.3 s, it can perform sensitive chemiluminescence detection of H2O2 and glucose within droplets. The linear detection ranges for these analytes are 10-50,000 and 20-600 µM, respectively, with the limit of detection being 0.648 and 0.334 µM. The significance of this chip lies in its ability to reveal changes in both electrical and chemical signals during transient biological processes. Its potential applications are numerous, encompassing a wide range of emerging areas such as single-cell analysis, cell communication, and cellular immunity.

A tempo-spatial controllable microfluidic shear-stress generator for in-vitro mimicking of the thrombus.

Pathological conditions linked to shear stress have been identified in hematological diseases, cardiovascular diseases, and cancer. These conditions often exhibit significantly elevated shear stress levels, surpassing 1000 dyn/cm2 in severely stenotic arteries. Heightened shear stress can induce mechanical harm to endothelial cells, potentially leading to bleeding and fatal consequences. However, current technology still grapples with limitations, including inadequate flexibility in simulating bodily shear stress environments, limited range of shear stress generation, and spatial and temporal adaptability. Consequently, a comprehensive understanding of the mechanisms underlying the impact of shear stress on physiological and pathological conditions, like thrombosis, remains inadequate. To address these limitations, this study presents a microfluidic-based shear stress generation chip as a proposed solution. The chip achieves a substantial 929-fold variation in shear stress solely by adjusting the degree of constriction in branch channels after PDMS fabrication. Experiments demonstrated that a rapid increase in shear stress up to 1000 dyn/cm2 significantly detached 88.2% cells from the substrate. Long-term exposure (24 h) to shear stress levels below 8.3 dyn/cm2 did not significantly impact cell growth. Furthermore, cells exposed to shear stress levels equal to or greater than 8.3 dyn/cm2 exhibited significant alterations in aspect ratio and orientation, following a normal distribution. This microfluidic chip provides a reliable tool for investigating cellular responses to the wide-ranging shear stress existing in both physiological and pathological flow conditions.

Smart Droplet Microfluidic System for Single-Cell Selective Lysis and Real-Time Sorting Based on Microinjection and Image Recognition.

Single-cell analysis has important implications for understanding the specificity of cells. To analyze the specificity of rare cells in complex blood and biopsy samples, selective lysis of target single cells is pivotal but difficult. Microfluidics, particularly droplet microfluidics, has emerged as a promising tool for single-cell analysis. In this paper, we present a smart droplet microfluidic system that allows for single-cell selective lysis and real-time sorting, aided by the techniques of microinjection and image recognition. A custom program evolved from Python is proposed for recognizing target droplets and single cells, which also coordinates the operation of various parts in a whole microfluidic system. We have systematically investigated the effects of voltage and injection pressure applied to the oil-water interface on droplet microinjection. An efficient and selective droplet injection scheme with image feedback has been demonstrated, with an efficiency increased dramatically from 2.5% to about 100%. Furthermore, we have proven that the cell lysis solution can be selectively injected into target single-cell droplets. Then these droplets are shifted into the sorting area, with an efficiency for single K562 cells reaching up to 73%. The system function is finally explored by introducing complex cell samples, namely, K562 cells and HUVECs, with a success rate of 75.2% in treating K562 cells as targets. This system enables automated single-cell selective lysis without the need for manual handling and sheds new light on the cooperation with other detection techniques for a broad range of single-cell analysis.

High-Throughput Functional Screening of Antigen-Specific T Cells Based on Droplet Microfluidics at a Single-Cell Level.

The lack of an efficient method for the identification of tumor antigen-specific T cell receptors (TCRs) impedes the development of T cell-based cancer immunotherapies. Here, we introduce a droplet-based microfluidic platform for function-based screening and sorting of tumor antigen-specific T cells with high throughput. We built a reporter cell line by co-transducing the TCR library and reporter genes at the downstream of TCR signaling, and reporter cells fluoresced upon functionally binding with antigens. We co-encapsulated reporter cells and antigen-presenting cells in droplets to allow for stimulation on a single-cell level. Functioning reporter cells specific against the antigen were identified in the microfluidic channel based on the fluorescent signals of the droplets, which were immediately sorted out using dielectrophoresis. We validated the reporter system and sorting results using flow cytometry. We then performed single-cell RNA sequencing on the sorted cells to further validate this platform and demonstrate the compatibility with genetic characterizations. Our platform provides a means for precise and efficient T cell immunotherapy, and the droplet-based high-throughput TCR screening method could potentially facilitate immunotherapeutic screening and promote T cell-based anti-tumor therapies.

Generation and Screening of Antigen-Specific Nanobodies from Mammalian Cells Expressing the BCR Repertoire Library Using Droplet-Based Microfluidics.

Nanobodies, also known as VHHs, originate from the serum of Camelidae. Nanobodies have considerable advantages over conventional antibodies, including smaller size, more modifiable, and deeper tissue penetration, making them promising tools for immunotherapy and antibody-drug development. A high-throughput nanobody screening platform is critical to the rapid development of nanobodies. To date, droplet-based microfluidic systems have exhibited improved performance compared to the traditional phage display technology in terms of time and throughput. In realistic situations, however, it is difficult to directly apply the technology to the screening of nanobodies. Requirements of plasma cell enrichment and high cell viability, as well as a lack of related commercial reagents, are leading causes for impeding the development of novel methods. We overcame these obstacles by constructing a eukaryotic display system that secretes nanobodies utilizing homologous recombination and eukaryotic transformation technologies, and the significant advantages are that it is independent of primary cell viability and it does not require plasma cell enrichment in advance. Next, a signal capture system of "SA-beads + Biotin-antigen + nanobody-6 × His + fluorescence-labeled anti-6 × His (secondary antibody)" was designed for precise localization of the eukaryotic-expressed nanobodies in a droplet. Based on this innovation, we screened 293T cells expressing anti-PD-L1 nanobodies with a high positive rate of targeted cells (up to 99.8%). Then, single-cell transcriptomic profiling uncovered the intercellular heterogeneity and BCR sequence of target cells at a single-cell level. The complete complementarity determining region (CDR3) structure was obtained, which was totally consistent with the BCR reference. This study expanded the linkage between microfluidic technology and nanobody applications and also showed potential to accelerate the rapid transformation of nanobodies in the large-scale market.

A Ti3 C2 TX /Pt-Pd based amperometric biosensor for sensitive cancer biomarker detection.

The detection of cancer biomarkers is of great significance for the early screening of cancer. Detecting the content of sarcosine in blood or urine has been considered to provide a basis for the diagnosis of prostate cancer. However, it still lacks simple, high-precision and wide-ranging sarcosine detection methods. In this work, a Ti3 C2 TX /Pt-Pd nanocomposite with high stability and excellent electrochemical performance has been synthesized by a facile one-step alcohol reduction and then used on a glassy carbon electrode (GCE) with sarcosine oxidase (SOx ) to form a sarcosine biosensor (GCE/Ti3 C2 TX /Pt-Pd/SOx ). The prominent electrocatalytic activity and biocompatibility of Ti3 C2 TX /Pt-Pd enable the SOx to be highly active and sensitive to sarcosine. Under the optimized conditions, the prepared biosensor has a wide linear detection range to sarcosine from 1 to 1000 µM with a low limit of detection of 0.16 µM (S/N = 3) and a sensitivity of 84.1 µA/mM cm2 . Besides, the reliable response in serum samples shows its potential in the early diagnosis of prostate cancer. More importantly, the successful construction and application of the amperometric biosensor based on Ti3 C2 TX /Pt-Pd will provide a meaningful reference for detecting other cancer biomarkers.

A peptide translated from circPPP1R12A promotes the malignancy of non-small cell lung cancer cells through AKT signaling pathway.

BACKGROUND: Recent literature have indicated that the malignancy of cancer cells is modulated by hsa_circ_0000423 (named circPPP1R12A) through the way of translating protein. Herein, we investigated the role and latent mechanisms of circPPP1R12A in Non-Small Cell Lung Cancer (NSCLC). METHODS: CircPPP1R12A expression was measured by qRT-PCR. The malignancy of NSCLC was determined by CCK-8, TUNEL assay, Wound healing, Transwell and Western blotting assays. The underlying mechanisms of circPPP1R12A were confirmed by Western blotting and qRT-PCR assays. RESULTS: CircPPP1R12A expression in NSCLC tissues was higher than that of neighboring normal tissues. CircPPP1R12A showed an upregulated expression in NSCLC cells. Upregulation of circPPP1R12A could promote the cell viability of NSCLC cells and reduce the apoptosis of NSCLC cells, while it could not promote cell invasion and migration. The reduction of cell viability and apoptosis was discovered in NSCLC cells with the silencing of circPPP1R12A, but circPPP1R12A knockdown does not inhibit cell invasion and migration. There was something interesting that circPPP1R12A encoding protein circPPP1R12A-73aa was found in NSCLC cells. Mutations in circPPP1R12a-73AA might disrupt the function of circPPP1ra-73AA in A549 and H1299 cells. Next, we found that circPPP1R12A caused the increased growth of NSCLC cells by activating AKT signaling pathway. CONCLUSION: In summary, our study proved that NSCLC cell proliferation was promoted by circPPP1R12A-73aa translated from circPPP1R12A through the AKT pathway, which could throw some light on the understanding of the mechanism of NSCLC.

Combined multi-band infrared camouflage and thermal management via a simple multilayer structure design.

Infrared camouflage is crucial for high-temperature objects to avoid detection, and spontaneous infrared radiation is also an important way for high-temperature objects to dissipate heat. Therefore, selective infrared emission has become significant for the coating design of surfaces such as aircraft, which require low emission in the atmospheric window band (3-5 µm and 8-14 µm) and high emission outside it (5-8 µm). This Letter employs a simple multilayer film structure to achieve selective regulation of the material emission spectrum. Combining the transfer matrix method and genetic algorithm, a multilayer film structure containing 12 layers of three high-temperature-resistant materials (SiO2, TiO2 and Ge) has been designed. It shows fairly low emissivity in two main bands of infrared detection (ε3∼5µm=0.14, ε8∼14µm=0.21) and high emissivity outside them (ε5∼8µm=0.86), and this infrared selectivity can be well maintained with the incident angle rising from 0 to 60 deg. The Poynting vector distribution in the material at different incident wavelengths is analyzed to further explore the interference mechanism to achieve spectral selective emission. The significance of this work lies in the construction of a relatively simple coating design while ensuring efficient infrared camouflage and thermal management performance.

Circular RNA circß-catenin aggravates the malignant phenotype of non-small-cell lung cancer via encoding a peptide.

BACKGROUND: More and more evidences demonstrate that circular RNAs (circNRAs) can encode protein. As a circRNA with translation capabilities, outcomes of circß-catenin in non-small cell lung cancer (NSCLC) still need to be explored. METHOD: The research methods of circß-catenin in the article include qRT-PCR, wound healing assay, CCK-8, colony formation, and Transwell assay. Western blotting and immunofluorescence were provided to detect protein expression levels and peptide encoded by circß-catenin, respectively. RESULTS: A prominently higher circß-catenin expression was found in NSCLC tissues. Silencing of circß-catenin was able to inhibit NSCLC cell migrating, invasive, and proliferative phenotypes. Overexpression of circß-catenin could enhance the migrating, invasive, and proliferative phenotypes of NSCLC cells. Importantly, circß-catenin was found to encode a peptide in NSCLC cells. Silencing or overexpression of circß-catenin could reduce or increase ß-catenin protein expression via suppressing the degradation of ß-catenin. CONCLUSION: Circß-catenin could promote NSCLC cell malignant phenotypes via peptide-regulated ß-catenin pathway. Our study provided a new understanding for the mechanisms of NSCLC.

Synthesis, herbicidal activity study and molecular docking of novel pyrimidine thiourea.

According to the pharmacophore binding strategy and principle of bioelectronic isobaric, used the sulfonylurea bridge as the parent structure, a series of novel thiourea compounds containing aromatic-substituted pyrimidines were designed and synthesized. The preliminary herbicidal activity tests showed that some compounds had good herbicidal activity against Digitaria adscendens, Amaranthus retroflexus, especially for compound 4d and 4f. The results showed that compound 4d had an inhibition rate of 81.5% on the root growth of Brassica napus L. at the concentration of 100 mg L-1, and compound 4f had an inhibition rate of 81% on the root growth of Digitaria adscendens at the concentration of 100 mg L-1. Compounds 4d and 4f had higher comparative activity on Echinochloa crus-galli than the commercial herbicide bensulfuron-methyl. The preliminary structure-activity relationship (SAR) was also summarized. We also tested the in vivo AHAS enzyme activity inhibition experiment of 14 compounds at 100 mg L-1, and the results showed that they all have inhibitory activity on the enzyme, with the highest inhibition rate reaching 44.4% (compound 4d). Based on the results of molecular docking to yeast acetohydroxyacid synthase (AHAS), the possible herbicidal activity mechanism of these compounds was evaluated.

Few-mode random fiber laser with a switchable oscillating spatial mode.

Random fiber lasers are of tremendous interest to diverse applications for optical fiber sensing, speckle-free imaging. To date, random fiber lasers with fundamental mode oscillation have been well developed. However, controllable oscillating spatial mode in random fiber lasers have not been reported yet. Here, we propose and demonstrate a few-mode random fiber laser with a switchable oscillating spatial mode based on mode injection locking. An external signal light is injected to realize the locking of transverse mode in this random fiber laser and the direct oscillations of the fundamental mode, hybrid mode, and high order mode can be realized, respectively. This random fiber laser operates in the high-order LP11 mode stably with a threshold of as low as 88 mW. High efficiency and high purity cylindrical vector beams can be obtained by removing the degeneracy of the LP11 mode. This work may pave a path towards random fiber lasers with controllable spatial modes for specific applications in mode division multiplexing, imaging, and laser material processing.

Stable generation of cylindrical vector beams with an all-fiber laser using polarization-maintaining and ring-core fibers.

An all-fiber laser using polarization-maintaining and ring-core fibers that are capable of automatically generating stable TE01 and TM01 modes is proposed and demonstrated experimentally. Two vector-mode coupling long-period fiber gratings (LPFGs) fabricated by a high-frequency CO2 laser are used in the fiber laser to realize efficient coupling between HE11 mode and TE01/TM01 mode. The polarization dependence of the LPFGs is simulated using the coupled-mode theory and verified by experiments. A ring-core fiber is employed to support the stable propagation of TE01 and TM01 modes. By carefully aligning the polarization direction of the input light, the mode coupling ratios of both LPFGs exceed 15 dB. The mode purities of TE01 and TM01 modes are 92.4% and 97.3%, respectively. Owing to the all-polarization-maintaining structure, the laser output is highly stable under environmental disturbance. This laser can be used as a stable cylindrical vector beam source for a wide range of applications, including surface plasmon excitation, optical tweezers, high-resolution metrology and so on.

Plantar Pressure Distribution of Right and Left Foot in Bilateral Clubfoot Treated by Ponseti Method: A Correlation Analysis.

BACKGROUND Congenital clubfoot is a common pediatric orthopedic deformity that can be corrected by Ponseti method, and pedobarographic analysis has been used to assess the outcomes. However, the relationship between the plantar pressure distribution of the right and left foot in children with bilateral clubfoot has not been studied. In this study, the pedobarographic data of patients with bilateral clubfoot who were treated by the Ponseti method were reviewed, and a correlation analysis was conducted to clarify the relationship between the right and left foot. MATERIAL AND METHODS A retrospective cross-sectional study of children with bilateral clubfoot who were treated by the Ponseti method in infancy was performed, in which all the patients were available for clinical evaluation, and pedobarographic analysis was conducted on each patient after treatment. The Pearson's correlation coefficient (r) were calculated for all the measurements of the left and right foot. RESULTS A total of 20 children (mean age 6.9±1.07 years, range 4-8 years) with bilateral clubfoot who were treated by the Ponseti method were included. The Dimeglio and Pirani scores before and after treatment between the right and left foot were significantly correlated. All the pedobarographic measurements between the left and right foot were correlated, indicating different degrees of positive correlation. CONCLUSIONS The plantar pressure measurements between the 2 feet in patients with bilateral clubfoot were highly correlated before treatment, and a correlation was also observed after those patients were treated by the Ponseti method. We should take these correlations into consideration during study design and analysis of clubfoot cases.

A novel circulating miRNA-based signature for the early diagnosis and prognosis prediction of non-small-cell lung cancer.

BACKGROUND: Non-small-cell lung cancer (NSCLC) is a significant public health issue worldwide. The aim of our study was to develop a serum miRNA-based molecular signature for the early detection and prognosis prediction of NSCLC. METHODS: The significantly altered circulating miRNAs were profiled in GSE24709. The top ten upregulated miRNAs were miR-432, miR-942, miR-29c-5p, miR-601, miR-613, miR-520d-3p, miR-1261, miR-132-5p, miR-302b, and miR-154-5p, while the top ten downregulated miRNAs were miR-562, miR-18b, miR-9-3p, miR-154-3p, miR-20b, miR-18a, miR-487a, miR-20a, miR-103, and miR-144. Then, the top four upregulated serum miRNAs (miR-432, miR-942, miR-29c-5p, and miR-601) were validated by real-time quantitative PCR. The clinical significance of two candidate serum miRNAs, miR-942 and miR-601, was further explored. RESULTS: Our results showed that the expression levels of serum miR-942 and serum miR-601 were significantly upregulated in NSCLC. In addition, serum miR-942 and serum miR-601 showed better performance than CEA, CYFRA21-1, and SCCA for early diagnosis of NSCLC. Combining serum miR-942 and serum miR-601 enhanced the efficacy of detecting early-stage NSCLC. Moreover, high serum miR-942 and serum miR-601 were both associated with adverse clinical variables and poor survival. The NSCLC patients with simultaneously high serum miR-942 and serum miR-601 suffered worst clinical outcome, while those with simultaneously low serum miR-942 and serum miR-601 had most favorable outcome. The multivariate analysis showed that serum miR-942 and serum miR-601 were independent prognostic factors for NSCLC. CONCLUSIONS: Taken together, serum miR-942 and serum miR-601 might serve as a promising molecular signature for the early detection and prognosis prediction of NSCLC.

Flow-Through Free Anterolateral Thigh Flap in Reconstruction of Severe Limb Injury.

OBJECTIVE: This study aimed to present the use of flow-through free anterolateral thigh (ALT) flap for the reconstruction of severe limb injury. PATIENTS AND METHODS: Four patients (2 male and 2 female subjects), with an average age of 26 (9-39) years, were included. These injuries referred to upper and lower limbs, including bone, soft tissue, nerve, and arterial segments. Two patients experienced large soft tissue defects in the lower limb and were repaired by double flow-through ALT flaps. The sizes of damaged soft tissues in the remaining 2 patients were 14 × 10 cm and 21 × 13 cm, respectively. Three patients had bone fractures, in which one of them experienced bone shortening during operation. The arterial injury was observed in 2 patients and the lengths of defects were 5 and 12 cm, respectively. Flow-through free ALT flap was applied for all 4 patients. RESULTS: Patients were followed up for 18 months. All the flaps have survived successfully without any vascular crisis or infection. All incision wounds were under primary healing stage, without any severe complications. The flaps showed better appearance, color, texture, and satisfactory sensation. All patients had satisfactory functional recovery of their injured limbs. CONCLUSIONS: The flow-through free ALT flap assists in overcoming complex traumatic injuries with severe soft tissue and arterial defects in the limbs. This flow-through ALT flap can be an effective alternative for reconstruction of severe limb injury.

Long noncoding RNA 00460 (LINC00460) promotes glioma progression by negatively regulating miR-320a.

OBJECTIVE: Long noncoding RNA 00460 (LINC00460) has been reported to contribute to tumorigenesis in multiple types of human malignancies. However, the biological role and the underlying molecular mechanism of LINC00460 in glioma remain unclear. The aim of this study was to investigate the clinical value, the biological function, and the potential mechanism of LINC00460 in glioma. METHODS: The expression level of LINC00460 in glioma tissues and cell lines was examined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell Counting Kit-8, flow cemetery, wound healing, and transwell invasion assays were used to explore the effect of LINC00460 on glioma cell proliferation, apoptosis, migration, and invasion. qRT-PCR and reporter assays were used to further verify the regulatory mechanism of LINC00460 in glioma progression. RESULTS: LINC00460 expression was upregulated in glioma tissues and cell lines compared with non-tumor brain samples and astrocyte cell line (NHA), respectively. Moreover, increased LINC00460 expression was closely associated with glioma tumor grade. Loss-of-function assays revealed that knockdown of LINC00460 significantly inhibited glioma cell proliferation, induced cell apoptosis, and suppressed migration and invasion. The mechanistic assays disclosed that LINC00460 binded to miR-320a in a sequence-specific manner and regulated its expression. Moreover, miR-320 inhibition partially attenuated LINC00460 knockdown-mediated suppressive effects on glioma cell proliferation, migration, and invasion. CONCLUSION: These findings suggested that LINC00460 might function as an oncogenic lncRNA in glioma development and could be explored as a potential therapeutic target for glioma.

Identifying potential metastasis-related long non-coding RNAs, microRNAs, and message RNAs in the esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is the predominant form with the highest incidence. We aimed to find metastasis-related differentially expressed long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and messenger RNA (mRNAs) in ESCC. We first obtained the lncRNAs, miRNAs, and mRNAs profiles. The differentially expressed lncRNAs, miRNAs, and mRNAs were obtained, followed by the functional annotation. Then the interaction networks of miRNA-mRNA, lncRNA-mRNA coexpression, lncRNA-miRNA, and lncRNA-miRNA-mRNA were constructed. In addition, systematic expression pattern analysis of differentially expressed lncRNAs, miRNA, and mRNA in the normal, metastasis, and nonmetastasis was performed. Survivability of differentially expressed lncRNAs, miRNAs, and mRNA was analyzed. A total of 613 differentially expressed lncRNAs, 35 differentially expressed miRNAs, and 1586 differentially expressed mRNAs were obtained. Several interactions of H19-hsa-mir-222-chromobox 2 (CBX2), H19-hsa-mir-330-phosphoinositide-3-kinase regulatory subunit 4 (PIK3R4), KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1)/CTB-89H12.4-hsa-mir-374a-vascular endothelial growth factor A (VEGFA), MALAT1/X inactive specific transcript (XIST)/XIST antisense RNA (TSIX)-hsa-mir-340-tumor necrosis factor receptor superfamily member 10A (NFRSF10A) were identified to play key roles in the metastasis of ESCC. In addition, KCNQ1OT1, TSIX, and XIST were significantly associated with the survival time of patients. In conclusion, our study may be helpful in understanding the pathological mechanism and providing new diagnostic and therapeutic biomarkers for ESCC.

Novel Wax Valves To Improve Distance-Based Analyte Detection in Paper Microfluidics.

Microfluidic paper-based analytical devices (µPADs) have been extensively studied for disease diagnostics, food quality control, and environmental monitoring due to the advantages of low cost, portability, and simplicity. The lack of flow controllability has triggered the development of valves for such devices. This paper reports the µPADs integrating novel wax valves for distance-based detection. The valves are printed on paper and can be manually opened by organic solvents within seconds. The opened valve does not influence the flow. The µPADs with wax valves were then applied in the distance-based detection of potassium iodate and glucose. The valves allow mixing of reagents and subsequent incubation in the loading zone, resulting in a shorter detection time and larger linear detection range. This study has demonstrated a linear detection range of 0.05-0.5 mM for potassium iodate, while linear ranges of 1-5 and 2.5-80 mg/dL are achieved for glucose when total detection time is 15 and 25 min, respectively. The lower detection limit is only 1/11 of that in a previous study. The detection ranges of iodate and glucose assays cover the concentrations of iodate in salt/milk and glucose in human saliva, respectively. Due to the simplicity, reliability, and ability for high-density integration, the µPADs with wax valves are of great potential in point-of-care (sampling) applications.

All-fiber high-order mode laser using a metal-clad transverse mode filter.

We propose and demonstrate an all-fiber laser with LP11 mode output. A transverse mode filter is designed and fabricated to suppress the fundamental mode and enable the fiber laser to oscillate in the second-order (LP11) transverse mode. The mechanism is to introduce relatively low ohmic loss for the TE01 mode and much higher ohmic losses for other modes through the loss of evanescent waves in the metal clad. The fiber laser operates at the center wavelength of 1053.9 nm with a narrow 3 dB linewidth of 0.019 nm. Four states of cylindrical vector mode with high modal purity are obtained through adjusting the intra-cavity polarization controller. This approach has great potentiality and scalability of realizing single high-order mode fiber laser, from which a wide range of applications could benefit.

Isoalantolactone Inhibits Esophageal Squamous Cell Carcinoma Growth Through Downregulation of MicroRNA-21 and Derepression of PDCD4.

BACKGROUND: This study was designed to explore the anticancer potential of isoalantolactone, a sesquiterpene lactone, on esophageal squamous cell carcinoma (ESCC) cells and associated molecular mechanisms. METHODS: ESCC cell lines were treated with isoalantolactone or vehicle and tested for viability, proliferation, cell cycle distribution, and apoptosis. Xenograft tumor studies in nude mice were done to examine the in vivo anticancer effect of isoalantolactone. RESULTS: Isoalantolactone treatment reduced ESCC cell viability and proliferation in vitro, which was coupled with induction of G0/G1 cell cycle arrest and apoptosis. In vivo studies confirmed the growth-suppressive effect of isoalantolactone on ESCC cells. Mechanistically, isoalantolactone reversed microRNA-21-mediated repression of programmed cell death 4 (PDCD4). Overexpression of microRNA-21 and knockdown of PDCD4 blocked the growth suppression and apoptosis induction by isoalantolactone in ESCC cells. CONCLUSIONS: Isoalantolactone shows growth-suppressive activity against ESCC cells, which is ascribed to upregulation of PDCD4 via downregulation of microRNA-21.