Design of robust superhydrophobic surfaces.

The ability of superhydrophobic surfaces to stay dry, self-clean and avoid biofouling is attractive for applications in biotechnology, medicine and heat transfer1-10. Water droplets that contact these surfaces must have large apparent contact angles (greater than 150 degrees) and small roll-off angles (less than 10 degrees). This can be realized for surfaces that have low-surface-energy chemistry and micro- or nanoscale surface roughness, minimizing contact between the liquid and the solid surface11-17. However, rough surfaces-for which only a small fraction of the overall area is in contact with the liquid-experience high local pressures under mechanical load, making them fragile and highly susceptible to abrasion18. Additionally, abrasion exposes underlying materials and may change the local nature of the surface from hydrophobic to hydrophilic19, resulting in the pinning of water droplets to the surface. It has therefore been assumed that mechanical robustness and water repellency are mutually exclusive surface properties. Here we show that robust superhydrophobicity can be realized by structuring surfaces at two different length scales, with a nanostructure design to provide water repellency and a microstructure design to provide durability. The microstructure is an interconnected surface frame containing 'pockets' that house highly water-repellent and mechanically fragile nanostructures. This surface frame acts as 'armour', preventing the removal of the nanostructures by abradants that are larger than the frame size. We apply this strategy to various substrates-including silicon, ceramic, metal and transparent glass-and show that the water repellency of the resulting superhydrophobic surfaces is preserved even after abrasion by sandpaper and by a sharp steel blade. We suggest that this transparent, mechanically robust, self-cleaning glass could help to negate the dust-contamination issue that leads to a loss of efficiency in solar cells. Our design strategy could also guide the development of other materials that need to retain effective self-cleaning, anti-fouling or heat-transfer abilities in harsh operating environments.

A standing Leidenfrost drop with Sufi whirling.

When a water drop is placed on a hot solid surface, it either undergoes explosive contact boiling or exhibits a stable state. In the latter case, the drop floats over an insulating layer of vapor generated by rapid vaporization of water at the surface/drop interface; this is known as the Leidenfrost state. Here, we discuss a previously unrecognized steady state in which a water drop "stands" on a hot smooth surface. In this state, the drop stabilizes itself with partial adhesion on the hot surface, leading to unique deformation and rotation behavior reminiscent of Sufi whirling-a form of spinning dance. Our analysis of this standing Leidenfrost state reveals the underlying mechanisms that drive the drop's stable partial adhesion and subsequent deformation with rotation. The heat-transfer efficiency of this standing state is up to 390% greater than that of the traditional floating Leidenfrost state.

Lipocalin-2 promotes neutrophilic inflammation in nasal polyps and its value as biomarker.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a common chronic inflammatory disease of the nasal cavity and paranasal sinuses. The role of neutrophils in the pathogenesis of CRSwNP has attracted more attention in recent years, due to its association with more severe disease and reduced steroid responsiveness. Lipocalin-2 (LCN2) has been found to modulate neutrophils infiltration in other neutrophilic inflammation including inflammatory bowel disease, rheumatoid arthritis, and psoriasis. The aim was to evaluate the expression and regulator role of LCN2 in neutrophilic inflammation in CRSwNP, and its role as a potential biomarker predicting non-eosinophilic CRSwNP (neCRSwNP). METHODS: Bioinformatic analysis, immunostainings, real-time PCR and ELISA were used to analyze the expression and location of LCN2 in nasal tissues. The expression of proinflammatory mediators were assessed in nasal tissues and secretions. LCN2 production in human nasal epithelial cells (HNECs) and neutrophils, as well as its role in neutrophilic inflammation was evaluated by in vitro experiments. RESULTS: LCN2 was mainly located in neutrophils and HNECs of nasal polyps. LCN2 expression was also significantly higher in the polyp tissue and nasal secretions from patients with neCRSwNP. The LCN2 levels were positively correlated with type 3 inflammation markers, including G-CSF, IL-8, and IL-17. LCN2 expression could be upregulated by IL-17 A and TNF-α in HNECs, and LCN2 could also promote the expression of IL-8 in dispersed polyp cells and HNECs. CONCLUSIONS: LCN2 could serve as a novel biomarker predicting patients with neCRSwNP, and the increased expression of LCN2 may participate in the pathogenesis of neCRSwNP.

A Time-Varying Mixture Integer-Valued Threshold Autoregressive Process Driven by Explanatory Variables.

In this paper, a time-varying first-order mixture integer-valued threshold autoregressive process driven by explanatory variables is introduced. The basic probabilistic and statistical properties of this model are studied in depth. We proceed to derive estimators using the conditional least squares (CLS) and conditional maximum likelihood (CML) methods, while also establishing the asymptotic properties of the CLS estimator. Furthermore, we employed the CLS and CML score functions to infer the threshold parameter. Additionally, three test statistics to detect the existence of the piecewise structure and explanatory variables were utilized. To support our findings, we conducted simulation studies and applied our model to two applications concerning the daily stock trading volumes of VOW.

Preliminary evidence for endoscopic surgery combined with postoperative anti-PD-1 immunotherapy in advanced recurrent nasopharyngeal carcinoma.

BACKGROUD: Endoscopic surgery can be used as the main treatment for advanced recurrent nasopharyngeal carcinoma (rNPC). However, there is a huge clinical controversy about the need for consolidated immunotherapy after surgery. METHODS: We performed a retrospective propensity score-matched analysis (1:2) of patients with locally advanced rNPC who underwent endoscopic nasopharyngectomy (ENPG) combined with anti-programmed cell death protein-1 (PD-1) monotherapy or ENPG alone. The survival rate was analyzed by Kaplan-Meier method. The primary endpoint was progression-free survival (PFS). The secondary endpoints included overall survival (OS), objective response rate (ORR) and disease control rate (DCR). Potential surgical-related complications and immune-related adverse events (AEs) were also assessed. RESULTS: We recruited 10 patients receiving ENPG plus anti-PD-1 monotherapy and 20 receiving ENPG alone. During the mean follow-up of 23.8 months, a significant improvement in the 2-year PFS was detected in the consolidation immunotherapy group compared to the ENPG alone group (80.0% vs. 40.0%; HR = 0.258; 95% CI: 0.09-0.72; p = 0.04), while the 2-year OS in the consolidation immunotherapy group was not significantly longer than that in the ENPG alone group (90.0% vs. 75.0%; HR = 0.482; 95% CI: 0.08-3.00; p = 0.50). The incidence of surgical-related complications in the consolidation immunotherapy group and ENPG alone group was 70.0 and 60.0%, respectively. Immune-related AEs were similar between the toripalimab arm (75.0%) and the camrelizumab arm (66.7%). Surgical-related complications depend on symptomatic treatments. Immune-related AEs were mild and tolerable. CONCLUSIONS: Consolidation immunotherapy regimen for patients with advanced rNPC after ENPG compared to ENPG alone provides a superior PFS rate with a manageable safety profile.

Preoperative Transarterial Embolization of Advanced Juvenile Nasopharyngeal Angiofibroma Using n-Butyl Cyanoacrylate: Case-Control Comparison with Microspheres.

PURPOSE: To evaluate the efficacy and safety of transarterial embolization (TAE) with n-butyl cyanoacrylate (nBCA) for juvenile nasopharyngeal angiofibroma (JNA). MATERIALS AND METHODS: A retrospective review was performed on patients with JNA who underwent TAE and endoscopic resection between 2020 and 2022. Patients embolized with nBCA were identified, and those embolized with microspheres were set as the control group. Data on demographics, symptoms, tumor characteristics, blood loss, adverse events, residual disease, and recurrence were collected, and case-control analysis was performed for the 2 groups. Differences in characteristics between the groups were tested using the Fisher exact and Wilcoxon tests. A generalized linear model (GLM) was used to analyze the univariate and multivariate influences on blood loss. RESULTS: Twenty patients were included in this study: 13 in the microsphere group and 7 in the nBCA group. The median blood loss was 400 mL (interquartile range [IQR], 200-520 mL) in the nBCA group and 1,000 mL (IQR, 500-1,000 mL) in the microsphere group (P = .028). The GLM confirmed lower blood loss in the nBCA group (relative risk, 0.58 [0.41-0.83]; P = .01). A residual tumor was found in 1 patient in each group (7.7% vs 14.3%; P = 1.000). Recurrence was not observed in any patient. None of the patients experienced adverse events during embolization. CONCLUSIONS: TAE of advanced JNA with nBCA glue is safe and effective and can significantly reduce intraoperative blood loss compared with microspheres.

Increased IL-1α expression in chronic rhinosinusitis with nasal polyps.

PURPOSE: To examine whether and how interleukin (IL)-1α is involved in chronic rhinosinusitis with nasal polyps (CRSwNP). METHODS: Nasal polyp (NP) and control tissues were collected from CRSwNP patients and control subjects. The expression of IL-1α and other proinflammatory cytokines (IL-1ß, IL-8 and IL-13, etc.), as well as neutrophil and eosinophil accumulation, were examined in sinonasal tissues using immunohistochemical (IHC), immunofluorescent (IF) staining, qPCR, and Luminex, respectively. Moreover, the regulation of IL-1α expression and its effects on other proinflammatory cytokines were evaluated in cultured nasal epithelial cells (NECs). RESULTS: The mRNA and protein levels of IL-1α were significantly higher in NP tissues compared to that in control tissues. IL-1α in polyp tissues was mainly located in epithelial cells and neutrophils. Polyps IL-1α level was significantly associated with IL-8, IL-1ß, IL-6, IL-4 and IL-13 production, as well as tissue neutrophil infiltration. Moreover, poly (I:C), lipopolysaccharides, Flagellin, R848 and cytokines (IL-4, IL-5, and IL-13) significantly increased the expression of IL-1α in cultured NECs in vitro, and recombinant IL-1α significantly promoted production of IL-8 and CXCL1 in cultured NECs. CONCLUSIONS: These findings provided the evidence that IL-1α were significantly increased in NP tissues, which may contribute to tissue neutrophilia in CRSwNP patients in China.

Subjective symptoms as predictors for eosinophilic chronic rhinosinusitis with nasal polyps in the Chinese population.

PURPOSE: To evaluate the putative association between subjective symptoms and eosinophilic inflammation in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). METHODS: A total of 102 patients with CRSwNP who underwent endoscopic sinus surgery were prospectively enrolled. The Sinonasal Outcomes Test-22 scores (SNOT-22), EuroQol 5-dimensional Questionnaire scores (ED-5D), and Lund-Mackay scores by computed tomography (CT) were obtained. Patients were grouped as eosinophilic CRSwNP (eCRSwNP) and non-eosinophilic CRSwNP (neCRSwNP). ECRSwNP was defined if tissue eosinophils of nasal polyps were greater than or equal to 8/HPF according to positive major basic protein (MBP) staining, and neCRSwNP otherwise. RESULTS: Thirty neCRSwNP and 72 eCRSwNP patients were included. ECRSwNP patients had higher incidences of asthma (p = 0.001), allergic rhinitis (p = 0.001), and ethmoid-to-maxillary opacification ratio on CT scans (p < 0.001), whereas the proportion of purulent discharge (p < 0.001) and maxillary sinus score (p = 0.002) was higher in the neCRSwNP patients. There were no significant differences between patients on the mains of the EQ-5D health utility values and total SNOT-22 score. However, eCRSwNP patients had higher SNOT-22 scores of sneezing (p = 0.006), runny nose (p < 0.001), and ear/facial domain (p = 0.012), and lower scores of thick nasal discharge (p = 0.015) and blockage (p = 0.042). Sneezing, thick nasal discharge, and blockage/congestion of nose were recognized as independent factors of CRSwNP. CONCLUSION: Sneezing was an independent predictor of eCRSwNP, and thick nasal discharge and blockage/congestion of nose were independent predictors of neCRSwNP.

Serum and glucocorticoid-regulated kinase 1 regulates transforming growth factor ß1-connective tissue growth factor pathway in chronic rhinosinusitis.

PURPOSE: Serum/glucocorticoid-regulated kinase 1 (SGK1) has been identified as a crucial regulator in fibrotic disorders. Herein, we explored SGK1 role in tissue remodeling of chronic rhinosinusitis (CRS). METHODS: Lentivirus was employed to generate an SGK1-overexpressing human bronchial epithelial cell (16HBE) line. To screen SGK1 downstream genes, RNA sequencing was performed on SGK1-overexpressing and control cell lines. To determine protein and gene expression levels, immunohistochemistry, western blotting, and quantitative real-time polymerase chain reaction were employed. Correlation analysis was performed using mRNA expression levels of SGK1, transforming growth factor ß1 (TGF-ß1), and connective tissue growth factor (CTGF) derived from CRS mucosal tissue and GEO database. Gene set enrichment analysis was conducted using gene sets from Molecular Signatures Database. The severity of symptoms in CRS patients was assessed using the 22-Item Sinonasal Outcome Test. RESULTS: SGK1 overexpression significantly increased the expression of connective tissue growth factor (CTGF) in 16HBE cells (P < 0.01). Consistently, CTGF protein level was considerably greater in mucosal tissue of CRS without nasal polyps (CRSsNP) than in CRS with nasal polyps (CRSwNP) (P < 0.05) or in control subjects (P < 0.01). TGF-ß1 protein level was higher in mucosal tissue of CRSsNP patients than in CRSwNP patients (P < 0.001) or in the control group (P < 0.01). mRNA levels of SGK1 and CTGF (P < 0.05, r = 0.668; P = 0.001, r = 0.630), TGF-ß1 and CTGF (P < 0.05, r = 0.560; P < 0.05, r = 0.420), as well as SGK1 and TGF-ß1(P < 0.05, r = 0.612; P < 0.05, r = 0.524) were significantly correlated in CRS mucosal tissue and GSE36830 dataset, respectively. TGF-ß1-induced upregulated genes were significantly enriched in SGK1 overexpression group. In vitro assays, TGF-ß1 promoted SGK1 and CTGF expression in a concentration- and time-dependent manner. Administrating an SGK1 inhibitor, GSK650394, significantly inhibited TGF-ß1-induced CTGF expression in 16HBE and dispersed primary nasal polyp cells. CONCLUSIONS: TGF-ß1 stimulation significantly increases SGK1 and CTGF expression. By regulating TGF-ß1-CTGF pathway, SGK1 may participate in tissue remodeling in the pathological mechanism of CRS.

Analysis of clinicopathologic features and expression of NR4A3 in sinonasal acinic cell carcinoma.

Acinic cell carcinoma (AiCC) in the nasal cavity and paranasal sinuses has rarely been reported in literature. A recent study demonstrated that recurrent genomic rearrangement [t(4;9) (q13;q31)] is a driver event in AiCC of the salivary glands that could promote the upregulation of transcription factor nuclear receptor subfamily 4 group A member 3 (NR4A3). In the current study, we evaluated the clinicopathological characteristics and expression of NR4A3 in four new cases of sinonasal AiCC. All four patients were men (range, 27-70 years). The tumor involved only the nasal cavity in two patients, while the other two patients showed involvement of both the nasal cavity and ethmoid sinus. Histologically, the tumor displayed a predominantly solid growth pattern and was composed of hematoxyphilic serous-like cells and scattered intercalated duct-like cells. Immunohistochemically, all cases expressed DOG-1. However, staining for mammaglobin, S-100, CA9, and P63 was absent in all patients. All four cases showed positive nuclear staining for NR4A3. In contrast, none of the other 39 sinonasal tumors, including secretory carcinomas, pleomorphic adenomas, mucoepidermoid carcinomas, adenoid cystic carcinomas, renal cell-like adenocarcinomas, intestinal-type adenocarcinomas, non-intestinal-type adenocarcinomas, extraskeletal myxoid chondrosarcoma, and carcinoma ex pleomorphic adenomas, presented with any positive NR4A3 nuclear staining. Additionally, NR4A3 rearrangements were observed in three cases with sinonasal AiCC by fluorescence in situ hybridization, and the expression level of NR4A3 mRNA was significantly increased in sinonasal AiCC compared with that in normal parotid tissue. Our study demonstrated that sinonasal AiCCs are characterized by an indolent nature and histopathological similarity to parotid AiCCs. Moreover, NR4A3 is a reliable biomarker for distinguishing sinonasal AiCCs from other sinonasal carcinomas.

Robust superhydrophobicity: mechanisms and strategies.

Superhydrophobic surfaces hold great prospects for extremely diverse applications owing to their water repellence property. The essential feature of superhydrophobicity is micro-/nano-scopic roughness to reserve a large portion of air under a liquid drop. However, the vulnerability of the delicate surface textures significantly impedes the practical applications of superhydrophobic surfaces. Robust superhydrophobicity is a must to meet the rigorous industrial requirements and standards for commercial products. In recent years, major advancements have been made in elucidating the mechanisms of wetting transitions, design strategies and fabrication techniques of superhydrophobicity. This review will first introduce the mechanisms of wetting transitions, including the thermodynamic stability of the Cassie state and its breakdown conditions. Then we highlight the development, current status and future prospects of robust superhydrophobicity, including characterization, design strategies and fabrication techniques. In particular, design strategies, which are classified into passive resistance and active regeneration for the first time, are proposed and discussed extensively.

Endoplasmic reticulum stress exacerbates inflammation in chronic rhinosinusitis with nasal polyps via the transcription factor XBP1.

Endoplasmic reticulum (ER) stress results in the activation of the unfolded protein response (UPR), a process that is involved in the pathogenesis of many inflammatory diseases. However, the role of ER stress in chronic rhinosinusitis with nasal polyps (CRSwNP) has yet to be elucidated. In this study, we found that the protein expression levels of a range of ER stress regulators, including p-PERK, ATF4, ATF6 and XBP1s, were significantly increased in CRSwNP compared to controls. Importantly, the expression of ATF4 and XBP1s was positively correlated with heightened inflammation in CRSwNP. In human nasal epithelial cells, the ER stress inducer tunicamycin (TM) could potentiate Toll-like receptors (TLRs) induced proinflammatory cytokines production. Furthermore, we found that the silencing of XBP1, but not ATF4 or ATF6, abrogated the proinflammatory effect of TM. Mechanistically, ER stress did not affect the NF-κB, MAPK or IRF3 signaling pathways. However, the ER stress regulator XBP1s was able to bind directly to the promoter region of inflammatory genes to modulate gene transcription. Besides, the commensal bacteria Staphylococcus aureus and several inflammatory factors, such as IL4, IL13, IL17 and IFNγ, could induce ER stress in epithelial cells. Collectively, ER stress plays a crucial role in facilitating TLR-induced inflammation. Targeting XBP1 can inhibit the inflammatory response, thus offering a potential approach to treat CRSwNP.

Clinicopathological analysis of low-grade papillary Schneiderian carcinoma: report of five new cases and review of the literature.

AIMS: Low-grade papillary Schneiderian carcinoma (LGPSC) is a rare and newly described entity of the sinonasal tract. The aim of this study was to evaluate the clinicopathological and molecular characteristics in order to identify typical features for differential diagnosis. METHODS AND RESULTS: Of the 3000 cases of sinonasal tumour studied during a period of 6 years, five cases were reviewed and diagnosed as LGPSC. All five patients were female (mean age, 47.8 years; range, 18-64 years) and had undergone multiple surgeries (3-10 surgeries). Both the sinonasal tract and the middle ear were involved in four patients. Nodal metastasis occurred in two patients, and one patient developed a distant metastasis to the left lung. Histologically, tumours had branched and crowded papillae with pushing boundaries. Tumour epithelia were multilayered and arranged in an orderly pattern without cilia. No malignant cytological features were observed in any of the cases. Immunohistochemical findings revealed a scattered distribution of Ki67-positive cells and positive staining for epithelial membrane antigen, mainly in the outermost-layer cells. Human papillomavirus (HPV) DNA was found in two patients and genotyped as HPV type 16. Sanger sequencing did not reveal any epidermal growth factor receptor or Kirsten rat sarcoma viral oncogene homologue gene mutation in the five cases. CONCLUSIONS: We report on five new cases of LGPSC, and confirm LGPSC as a new sinonasal carcinoma that behaves aggressively with metastatic potential. The combination of clinical behaviour and typical histological features can distinguish LGPSC from sinonasal papilloma and other carcinomas.

The postoperative outcomes of patients with chronic rhinosinusitis with nasal polyps by sustained released steroid from hyaluronic acid gel.

PURPOSE: The self-crosslinked hyaluronic acid (scHA) and steroids are considered as efficient factors for postoperative management after chronic rhinosinusitis (CRS) nasal surgery. This randomized clinical trial is designed to investigate the efficacy and potential of scHA gel as a topical drug sustained release carrier for steroid of budesonide. METHODS: The study is performed with 30 patients of chronic rhinosinusitis with nasal polyps (CRSwNP) who underwent functional endoscopic sinus surgery (FESS). The single application of scHA was assessed in the control patient group for postoperative recovery. In the treatment patient group, the combination of scHA/budesonide was applied for postoperative management. The patients are followed up in 2 weeks, 4 weeks and 12 weeks after surgery. RESULTS: The combination of scHA/budesonide results in better endoscopic scoring and mucus evaluation than the single scHA application. CONCLUSION: The results indicate that the combination of scHA/budesonide is a valuable treatment for the FESS postoperative management and implies the potential of scHA gel as a topical drug sustained release scaffold.

Assessment of Internal Carotid Artery Invasion With the Endoscopic Endonasal Approach: Implications of a New Grading System and Security Strategy.

BACKGROUND: Internal carotid artery (ICA) injury during the endoscopic endonasal approach (EEA) for ventral cranial base tumors is rare but fatal. OBJECTIVE: The aim of this study was to investigate the relationship between ventral cranial base tumors and corresponding ICA using quantitative means to improve the safety of surgery. MATERIAL AND METHODS: In this retrospective study, a total of 46 patients with ventral cranial base tumors undergoing surgery with the EEA were enrolled. Preoperative imaging features and clinical data were recorded. The influencing factors of the gross total resection (GTR) rate were analyzed. A new grading system and security strategy were developed. RESULTS: Postoperative enhanced magnetic resonance imaging showed a GTR of 61.7%. There was a significant correlation between the GTR rate and tumors surrounding the ICA, the tumor site, the involved ICA segment, and the blood supply (P < 0.05). We included preoperative radiotherapy as supplementary data in the grading system. Each variable involved the letter "S"; (surround, site, segment, blood supply, supplementary data); hence, the system was named the 5S ICA grading scale. CONCLUSION: We recommend a safety assessment through the 5S ICA grading scale and the ICA grading strategy to obtain the maximum total resection rate while ensuring patient safety.

Monitoring the Zero-Inflated Time Series Model of Counts with Random Coefficient.

In this research, we consider monitoring mean and correlation changes from zero-inflated autocorrelated count data based on the integer-valued time series model with random survival rate. A cumulative sum control chart is constructed due to its efficiency, the corresponding calculation methods of average run length and the standard deviation of the run length are given. Practical guidelines concerning the chart design are investigated. Extensive computations based on designs of experiments are conducted to illustrate the validity of the proposed method. Comparisons with the conventional control charting procedure are also provided. The analysis of the monthly number of drug crimes in the city of Pittsburgh is displayed to illustrate our current method of process monitoring.

Statistical Inference for Periodic Self-Exciting Threshold Integer-Valued Autoregressive Processes.

This paper considers the periodic self-exciting threshold integer-valued autoregressive processes under a weaker condition in which the second moment is finite instead of the innovation distribution being given. The basic statistical properties of the model are discussed, the quasi-likelihood inference of the parameters is investigated, and the asymptotic behaviors of the estimators are obtained. Threshold estimates based on quasi-likelihood and least squares methods are given. Simulation studies evidence that the quasi-likelihood methods perform well with realistic sample sizes and may be superior to least squares and maximum likelihood methods. The practical application of the processes is illustrated by a time series dataset concerning the monthly counts of claimants collecting short-term disability benefits from the Workers' Compensation Board (WCB). In addition, the forecasting problem of this dataset is addressed.

Surface charge printing for programmed droplet transport.

The directed, long-range and self-propelled transport of droplets on solid surfaces is crucial for many applications from water harvesting to bio-analysis1-9. Typically, preferential transport is achieved by topographic or chemical modulation of surface wetting gradients that break the asymmetric contact line and overcome the resistance force to move droplets along a particular direction10-16. Nonetheless, despite extensive progress, directional droplet transport is limited to low transport velocity or short transport distance. Here we report the high-velocity and ultralong transport of droplets elicited by surface charge density gradients printed on diverse substrates. We leverage the facile water droplet printing on superamphiphobic surfaces to create rewritable surface charge density gradients that stimulate droplet propulsion under ambient conditions17 and without the need for additional energy input. Our strategy provides a platform for programming the transport of droplets on flat, flexible and vertical surfaces that may be valuable for applications requiring a controlled movement of droplets17-19.

Surface-Charge-Assisted Microdroplet Generation on a Superhydrophobic Surface.

The ability to generate and manipulate droplets down to microscales has attracted great attention in a variety of applications, such as in printing, microreactors, and biological assays. However, the production of microdroplets is often limited by special equipment or the size of needles. Here, an unexplored and facile approach is demonstrated; microdroplets can be generated and trapped yet not pinned on a micro-nano-structured superhydrophobic surface by controllable surface charge during drop impact. Tiny droplets with a size at a scale of tens of microns to millimeters are generated by simply changing the impacting velocity, the size of the impact drop, or impact frequency. Theoretical analysis suggests the generation of the microdroplet as a result of the surface-charge-regulated adhesion, competing with liquid dynamic and interfacial energy. The distribution of surface charge which determines the size and the location of the microdroplet is at the top of the micro-nano-structured surface and dependent on the pressure field applied on the surface during the drop impact. The mobility of the resulting microdroplet that can be easily manipulated without liquid retention is also shown, by taking advantage of the shielding property of the surface charge. This facile yet effective method provides a promising candidate for the realization of tiny droplet-generating and -manipulating applications.

A caffeic acid phenethyl ester analog inhibits the proliferation of nasopharyngeal carcinoma cells via targeting epidermal growth factor receptor.

A previous study reported that compound 5A, a caffeic acid phenethyl ester (CAPE) analog, exhibited obvious neuroprotective activity, in particular, compound 5A possessed higher stability and membrane permeability than CAPE. CAPE displays antitumour function; therefore, evaluating the antitumour effect of its analog with higher stability and membrane permeability is worthwhile. We first investigated the antitumour activity of compound 5A. We found that compound 5A significantly inhibited the proliferation of tumor cells and showed low cytotoxicity in normal cells. Furthermore, compound 5A was found to induce the cell cycle arrest and apoptosis of CNE2 cells. Through the prediction of SwissTargetPrediction and subsequent confirmation, epidermal growth factor receptor (EGFR) was identified as a target of compound 5A. Compound 5A also influenced the expression of genes downstream of EGFR in nasopharyngeal carcinoma (NPC) cells. Based on these findings, compound 5A inhibits the proliferation of NPC cells by targeting EGFR and may become a new candidate compound for NPC treatment.