Operando Decoding of Surface Chemical and Thermal Events in Photoelectrocatalysis via a Lab-Around-Microfiber Sensor.

Operando decoding of the key parameters of photo-electric catalysis provides reliable information for catalytic effect evaluation and catalytic mechanism exploration. However, to capture the details of surface-localized and rapid chemical and thermal events at the nanoscale in real-time is highly challenging. A promising approach based on a lab-around-microfiber sensor capable of simulating photo-electric catalytic reactions on the surface of optical fibers as well as monitoring reactant concentration changes and catalytic heat generation processes is demonstrated. Due to the penetration depth of submicron size and the fast response ability of the evanescent field, the lab-around-microfiber sensor overcame the difficulty of reading instantaneous surface parameters in the submicron range. This sensor operando dismantled the changes in reactant concentration and temperature on the catalyst surface induced by light and voltage, respectively. It also decoded the impact of catalyst composition on the adsorption efficiency and catalytic efficiency across various wavelengths and determined the synchronized occurrence of pollutant degradation and catalytic thermal effects. Stable correlations between the real-time parameters and catalytic activities are obtained, helping to provide a basic understanding of the catalytic process and mechanism. This approach fills an important gap in the current monitoring methods of catalytic processes and heat production.

Urban-Rural Disparities in the Association Between Home- and Community-Based Service Utilization and Levels of Disability Among Chinese Older Adults With Disabilities.

Home- and community-based services (HCBS) are optimal ways to deal with disability problems among older adults. This study aims to analyze urban-rural disparities in the relationship between HCBS utilization and levels of disability among Chinese older adults with disabilities, so as to meet the long-term care needs of them. In applying the Andersen Behavioral Model, bivariate analysis and multivariate regression models were employed using data from 843 older adults with disabilities from the 2018 China Longitudinal Aging Social Survey (CLASS). After adjusting covariates, disability levels among Chinese older adults with disabilities were significantly correlated with HCBS utilization in urban areas but not in rural areas. The urban-rural disparities may be due to the low utilization of HCBS in rural areas (only 11.2%) among older adults with disabilities compared with their urban counterparts (22.7%).

Quantitative Assessment of Fungal Biomarkers in Clinical Samples via an Interface-Modulated Optical Fiber Biosensor.

Invasive fungal infections pose a significant public health threat. The lack of precise and timely diagnosis is a primary factor contributing to the significant increase in patient mortality rates. Here, an interface-modulated biosensor utilizing an optical fiber for quantitative analysis of fungal biomarkers at the early stage of point-of-care testing (POCT), is reported. By integrating surface refractive index (RI) modulation and plasmon enhancement, the sensor to achieve high sensitivity in a directional response to the target analytes, is successfully optimized. As a result, a compact fiber-optic sensor with rapid response time, cost-effectiveness, exceptional sensitivity, stability, and specificity, is developed. This sensor can successfully identify the biomarkers of specific pathogens from blood or other tissue specimens in animal models. It quantifies clinical blood samples with precision and effectively discriminates between negative and positive cases, thereby providing timely alerts to potential patients. It significantly reduces the detection time of fungal infection to only 30 min. Additionally, this approach exhibits remarkable stability and achieves a limit of detection (LOD) three orders of magnitude lower than existing methods. It overcomes the limitations of existing detection methods, including a high rate of misdiagnosis, prolonged detection time, elevated costs, and the requirement for stringent laboratory conditions.

Marriage of a Dual-Plasmonic Interface and Optical Microfiber for NIR-II Cancer Theranostics.

The use of light as a powerful tool for disease treatment has introduced a new era in tumor treatment and provided abundant opportunities for light-based tumor theranostics. This work reports a photothermal theranostic fiber integrating cancer detection and therapeutic functions. Its self-heating effect can be tuned at ultralow powers and used for self-heating detection and tumor ablation. The fiber, consisting of a dual-plasmonic nanointerface and an optical microfiber, can be used to distinguish cancer cells from normal cells, quantify cancer cells, perform hyperthermal ablation of cancer cells, and evaluate the ablation efficacy. Its cancer cell ablation rate reaches 89% in a single treatment. In vitro and in vivo studies reveal quick, deep-tissue photonic hyperthermia in the NIR-II window, which can markedly ablate tumors. The marriage of a dual-plasmonic nanointerface and an optical microfiber presents a novel paradigm in photothermal therapy, offering the potential to surmount the challenges posed by limited light penetration depth, nonspecific accumulation in normal tissues, and inadvertent damage in current methods. This work thus provides insight for the exploration of an integrated theranostic platform with simultaneous functions in cancer diagnostics, therapeutics, and postoperative monitoring for future practical applications.

Ccdc85c-Par3 condensates couple cell polarity with Notch to control neural progenitor proliferation.

Polarity proteins regulate the proliferation and differentiation of neural progenitors to generate neurons during brain development through multiple signaling pathways. However, how cell polarity couples the signaling pathways remains unclear. Here, we show that coiled-coil domain-containing protein 85c (Ccdc85c) interacts with the polarity protein Par3 to regulate the proliferation of radial glial cells (RGCs) via phase separation coupled to percolation (PSCP). We find that the interaction with Ccdc85c relieves the intramolecular auto-inhibition of Par3, which leads to PSCP of Par3. Downregulation of Ccdc85c causes RGC differentiation. Importantly, the open conformation of Par3 facilitates the recruitment of the Notch regulator Numb to the Par3 condensates, which might prevent the attenuation of Notch activity to maintain RGC proliferation. Furthermore, ectopic activation of Notch signaling rescues RGC proliferation defects caused by the downregulation of Ccdc85c. These results suggest that Ccdc85c-mediated PSCP of Par3 regulates Notch signaling to control RGC proliferation during brain development.

Plasmonic Coupling on an Optical Microfiber Surface: Enabling Single-Molecule and Noninvasive Dopamine Detection.

Optical fibers can be effective biosensors when employed in early-stage diagnostic point-of-care devices as they can avoid interference from molecules with similar redox potentials. Nevertheless, their sensitivity needs to be improved for real-world applications, especially for small-molecule detection. This work demonstrates an optical microfiber biosensor for dopamine (DA) detection based on the DA-binding-induced aptamer conformational transitions that occur at plasmonic coupling sites on a double-amplified nanointerface. The sensor exhibits ultrahigh sensitivity when detecting DA molecules at the single-molecule level; additionally, this work provides an approach for overcoming optical device sensitivity limits, further extending optical fiber single-molecule detection to a small molecule range (e.g., DA and metal ions). The selective energy enhancement and signal amplification at the binding sites effectively avoid nonspecific amplification of the whole fiber surface which may lead to false-positive results. The sensor can detect single-molecule DA signals in body-fluids. It can detect the released extracellular DA levels and monitor the DA oxidation process. An appropriate aptamer replacement allows the sensor to be used for the detection of other target small molecules and ions at the single-molecule level. This technology offers alternative opportunities for developing noninvasive early-stage diagnostic point-of-care devices and flexible single-molecule detection techniques in theoretical research.

Empathic concern induction modulates behavioral ratings and neural responses to harm-related moral judgment: An event-related potentials study.

Although empathic concern is critical in harm-related moral judgment, the temporal dynamics underlying the impact of empathic concern on moral judgment remain unclear. This study used event-related potentials (ERPs) to investigate how empathic concern induction shaped the way individuals perceive harmful/helpful behaviors. Behavioral results showed that participants assigned more blame to harmful behaviors in the empathic concern priming condition compared to those in the control condition. ERP results showed that helpful behaviors elicited larger N1 than did harmful behaviors. Additionally, harmful behaviors in the empathic concern priming condition elicited more negative N2 than did harmful behaviors in the control condition. Moreover, harmful behaviors elicited larger late positive potential (LPP) than did helpful behaviors in the control condition. These findings suggest that (1) empathic concern induction might increase moral sensitivity about harm-related norms; (2) participants independent of the empathic concern manipulation can distinguish between harmful behaviors and helpful behaviors similarly, as indicated by the early ERP component (N1); (3) empathic concern especially influences the intermediate (N2) and later (LPP) ERP components.

Developing a Capsule Clinic-A 24-Hour Institution for Improving Primary Health Care Accessibility: Evidence From China.

Telehealth is an effective combination of medical service and intelligent technology. It can improve the problem of remote access to medical care. However, an imbalance in the allocation of health resources still occurs. People spend more time and money to access higher-quality services, which results in inequitable access to primary health care (PHC). At the same time, patients' usage of telehealth services is limited by the equipment and their own knowledge, and the PHC service suffers from low usage efficiency and lack of service supply. Therefore, improving PHC accessibility is crucial to narrowing the global health care coverage gap and maintaining health equity. In recent years, China has explored several new approaches to improve PHC accessibility. One such approach is the capsule clinic, an emerging institution that represents an upgraded version of the internet hospital. In coordination with the United Nations, the Yinzhou district of Ningbo city in Zhejiang, China, has been testing this new model since 2020. As of October 2022, the number of applications in Ningbo was 15, and the number of users reached 12,219. Unlike internet hospitals, the entire process-from diagnosis to prescription services-can be completed at the capsule clinic. The 24-hour telehealth service could also solve transportation problems and save time for users. Big data analysis can accurately identify regional populations' PHC service needs and improve efficiency in health resource allocation. The user-friendly, low-cost, and easily accessible telehealth model is of great significance. Installation of capsule clinics would improve PHC accessibility and resolve the uneven distribution of health resources to promote health equity.

Preparation and Characterization of Graphene Oxide/Polyaniline/Polydopamine Nanocomposites towards Long-Term Anticorrosive Performance of Epoxy Coatings.

To address the challenging issues of metal materials corrosion in industries, which has caused huge economic losses and security threats to many facilities in marine environments, functional polymer coatings have been widely used and regarded as one of the simplest and most effective methods to prevent such an undesirable event. In this study, a new type of coating filler consisting of graphene oxide/polyaniline/polydopamine (GO-PANI-PDA) nanocomposites has been successfully synthesized. The morphology, structure, composition, and corrosion resistance performance of the GO-PANI-PDA (GPP) nanocomposites were investigated via a series of characterization methods. The results from our electrochemical impedance spectroscopy, potentiodynamic polarization curve and salt spray experiment showed that the best corrosion resistance performance of the coating is from GPP 21 with the epoxy/GO-PANI:PDA ratio of 2:1, which exhibited a positive corrosion potential (-0.51 V) shift from epoxy/GO-PANI coating (-0.64 V). The corrosion current density (3.83 × 10-8 A/cm2) of GPP 21 is nearly an order of magnitude lower than that of epoxy/GO-PANI (7.05 × 10-7 A/cm2). The good anti-corrosion performance was fascinatingly observed in salt spray tests even without obvious corrosion phenomenon after 30 days of testing. Due to these remarkable properties, GPP nanocomposites can be an outstanding candidate for the rapid development of broadband shielding and anticorrosive materials.

Can a multitiered copayment system affect people's healthcare-seeking behavior? A case study of Wenzhou, China.

BACKGROUND: Facilitating the primary health care (PHC) system and maintaining people's reasonable healthcare-seeking behavior are key to establishing a sustainable healthcare system. China has employed a multitiered copayment system/medical insurance differentiated payment policies to incentivize the public to utilize PHC services through its hierarchical medical care system; however, most people still prefer visiting tertiary care hospitals. We question whether the quality gap in healthcare services reduces the effect of the multitiered copayment system, which is considered an important factor in the lack of reform in the Chinese healthcare system. Thus, we explore the effect and influencing factors of the multitiered copayment system that drives primary healthcare-seeking behavior under the current situation with a large quality gap. We also consider the hypothetical situation of a reduced gap in the future. METHODS: This study used the hypothetical quality improvement scenario to elicit people's hypothetical behaviors, and a multistage stratified cluster random sampling method. This preliminary study was conducted in 2016 using 1829 individuals from four regions of Wenzhou in Zhejiang Province: Ouhai, Ruian, Yongjia, and Taishun. A descriptive statistical analysis, chi-square analysis, Fisher's exact test, and multinomial logistic regression model were performed to introduce the effect of the multitiered copayment system, and to explore the factors affecting the selection of PHC institutions at pre- and post-change phases. RESULT: The results show that compared with the large quality gap phase, the number of respondents who believed the multitiered copayment system had an effect on their selection of PHC institutions after the equalization of healthcare services quality increased threefold (from 14.0% to 50.8%). Moreover, the main determinants in people's selection of PHC institutions changed from age and needs variables (self-rated health status) to age, needs variables (self-rated health status) and enabling variables (distance to a medical care facility). CONCLUSION: The results indicate limited initial effects of the multitiered copayment system. However, they become more pronounced after the equalization of healthcare services quality. This study confirms that changes in the quality gap in healthcare services influence the effect of the multitiered copayment system. Hence, reducing this gap can help achieve the intended outcome of the tiered healthcare insurance schedule.

Cell cortex regulation by the planar cell polarity protein Prickle1.

The planar cell polarity pathway regulates cell polarity, adhesion, and rearrangement. Its cytoplasmic core components Prickle (Pk) and Dishevelled (Dvl) often localize as dense puncta at cell membranes to form antagonizing complexes and establish cell asymmetry. In vertebrates, Pk and Dvl have been implicated in actomyosin cortex regulation, but the mechanism of how these proteins control cell mechanics is unclear. Here we demonstrate that in Xenopus prechordal mesoderm cells, diffusely distributed, cytoplasmic Pk1 up-regulates the F-actin content of the cortex. This counteracts cortex down-regulation by Dvl2. Both factors act upstream of casein kinase II to increase or decrease cortical tension. Thus, cortex modulation by Pk1 and Dvl2 is translated into mechanical force and affects cell migration and rearrangement during radial intercalation in the prechordal mesoderm. Pk1 also forms puncta and plaques, which are associated with localized depletion of cortical F-actin, suggesting opposite roles for diffuse and punctate Pk1.

Optical Microfiber with a Gold Nanorods-Black Phosphorous Nanointerface: An Ultrasensitive Biosensor and Nanotherapy Platform.

The detection and therapy of cancers in the early stage significantly alleviate the associated dangers. Optical devices offer new opportunities for these early measures. However, the clinical translation of the existing methods is severely hindered by their relatively low sensitivity or unclear physiological metabolism. Here, an optical microfiber sensor with a drug loading gold nanorod-black phosphorous nanointerface, as an ultrasensitive biosensor and nanotherapy platform, is developed to meet the early-stage requirement. With interface sensitization and functionalization of the hybrid nanointerface, the microfiber sensor presents an ultrahigh sensing performance, achieving the selective detection of the HER2 biomarker with limits of detection of 0.66 aM in buffer solution and 0.77 aM in 10% serum. It can also distinguish breast cancer cells from other cells in the early stage. Additionally, enabled by the interface, the optical microfiber is able to realize cellular nanotherapy, including photothermal/chemotherapy with pump laser coupling after diagnosis, and evaluate therapy results in real time. The immobilization of the interface on the optical microfiber surface prevents the damage to normal cells induced by nanomaterial enrichment, making the device more efficient and intelligent. This study opens up a new avenue for the development of smart optical platforms for sensitive biosensing and precision therapy.

The Effect of Repetitive Transcranial Magnetic Stimulation (rTMS) on Cognition in Patients With Traumatic Brain Injury: A Protocol for a Randomized Controlled Trial.

Cognitive impairment, defined as a decline in memory and executive function, is one of the most severe complications of traumatic brain injury (TBI). Patients with TBI are often unable to return to work due to cognitive impairment and their overall quality of life is reduced. TBI can bring a serious economic burden to patient's families and to society. Reported findings on the efficacy of repetitive transcranial magnetic stimulation (rTMS) in improving cognitive impairment following TBI are inconsistent. The purpose of the proposed study is to investigate whether rTMS can improve memory and executive function in patients with TBI. Herein, we propose a prospective randomized placebo-controlled (rTMS, sham rTMS, cognitive training), parallel-group, single-center trial. 36 participants with a TBI occurring at least 6 months prior will be recruited from an inpatient rehabilitation center. Participants will be randomly assigned to the real rTMS, sham rTMS, or cognitive training groups with a ratio of 1:1:1. A 20-session transcranial magnetic stimulation protocol will be applied to the left and right dorsolateral prefrontal cortices (DLPFC) at frequencies of 10 Hz and 1 Hz, respectively. Neuropsychological assessments will be performed at four time points: baseline, after the 10th rTMS session, after the 20th rTMS session, and 30 days post-intervention. The primary outcome is change in executive function assessed using the Shape Trail Test (STT). The secondary outcome measures are measures from neuropsychological tests: the Hopkins Verbal Learning Test (HVLT), the Brief Visuospatial Memory Test (BVMT), the Digit Span Test (DST). We report on positive preliminary results in terms of improving memory and executive function as well as beneficial changes in brain connectivity among TBI patients undergoing rTMS and hypothesize that we will obtain similar results in the proposed study.

Preparation and Characterization of Graphene Oxide/Polyaniline/Carbonyl Iron Nanocomposites.

Nano coatings for anti-corrosion and electromagnetic wave absorbing can simultaneously implement the functions of assimilating electromagnetic waves and reducing the corrosion of materials caused by corrosive environments, such as seawater. In this work, a composite material for both electromagnetic wave absorption and anti-corrosion was prepared by an in-situ chemical oxidation and surface coating method using carbonyl iron powder (CIP), graphene oxide (GO) and aniline (AN). The synthesized composite material was characterized by scanning electron microscopy (SEM), infrared spectroscopy (FT-IR) and XRD. The carbonyl iron powder-graphene oxide-polyaniline (CIP-GO-PANI) composite material was used as the functional filler, and the epoxy resin was the matrix body for preparing the anticorrosive wave-absorbing coating. The results show that CIP had strong wave-absorbing properties, and the anti-corrosion property was greatly enhanced after being coated by GO-PANI.

Are there gender differences in the trajectories of self-rated health among chinese older adults? an analysis of the Chinese Longitudinal Healthy Longevity Survey (CLHLS).

BACKGROUND: Self-rated health (SRH) is a good predictor of morbidity and mortality. Extensive research has shown that females generally report poorer SRH than males but still tend to live longer. Previous studies used cross-sectional or pooled data for their analyses while ignoring the dynamic changes in males' and females' SRH statuses over time. Furthermore, longitudinal studies, especially those that focus on older adults, typically suffer from the incompleteness of data. As such, the effect of dropout data on the trajectories of SRH is still unknown. Our objective is to examine whether there are any gender differences in the trajectories of SRH statuses in Chinese older adults. METHODS: The trajectories of SRH were estimated using the pattern-mixture model (PMM), a special latent growth model, under non-ignorable dropout data assumption. We analyzed the Chinese Longitudinal Healthy Longevity Survey (CLHLS) data of 15,613 older adults aged 65 years and above, collected from 2005 to 2014. RESULTS: The results demonstrated the effect of non-ignorable dropout data assumptions in this study. The previous SRH score was negatively associated with the likelihood of dropping out of the study at the next follow-up survey. Our results showed that both males and females in China perceive their SRH as decreasing over time. A significant gender difference was found in the average SRH score (female SRH was lower than male SRH) in this study. Nonetheless, based on the results obtained using the PMM, there are no gender differences in the trajectories of SRH at baseline as well as in the rate of decline among the total sample. The results also show that males and females respond to SRH predictors similarly, except that current drinking has a more pronounced positive effect on males and healthcare accessibility has a more pronounced positive effect on females. CONCLUSIONS: Our results suggest that missing data have an impact on the trajectory of SRH among Chinese older adults. Under the non-ignorable dropout data assumptions, no gender differences were found in trajectories of SRH among Chinese older adults. Males and females respond to SRH predictors similarly, except for current drinking habit and healthcare accessibility.

3D nanointerface enhanced optical microfiber for real-time detection and sizing of single nanoparticles.

Portable devices, which can detect and characterize the individual nanoparticles in real time, are of insignificant interest for early diagnosis, homeland security, semiconductor manufacturing and environmental monitoring. Optical microfibers present a good potential in this field, however, are restricted by the sensitivity limit. This study reports the development of a 3D plasmonic nanointerface, which is made of a Cu-BTC framework supporting Cu3-xP nanocrystals, enhancing the optical microfiber for real-time detection and sizing of single nanoparticles. The Cu3-xP nanocrystals are successfully embedded in the 3D Cu-BTC framework. The localized-surface plasmon resonance is tuned to coincide with the evanescent field of the optical microfiber. The 3D Cu-BTC framework, as the scaffold of nanocrystals, confines the local resonance field on the microfiber with three dimensions, at which the binding of target nanoparticles occurs. Based on the evanescent field confinement and surface enhancement by the nanointerface, the optical microfiber sensor overcomes its sensitivity limit, and enables the detection and sizing of the individual nanoparticles. The compact size and low optical power supply of the sensor confirm its suitability as a portable device for the real-time single-nanoparticle characterization, especially for the convenient evaluation of the ultrafine particles in the environment. This work opens up an approach to overcome the sensitivity limit of the optical microfibers, as long with stimulating the portable real-time single-nanoparticle detection and sizing.

Injury of photoreceptors and retinal pigment epithelium in macular area of a preterm infant: A case analysis.

RATIONAL: Injury of photoreceptors and retinal pigment epithelium (RPE) in macular area of premature infants is very rare. PATIENT CONCERNS: A preterm infant delivered under general anesthesia. The infant was born at 28 weeks' and 4 days' gestation, with a birth weight of 1.15 kg and a treatment of oxygen inhalation after birth. According to the related protocol formulated by the Ophthalmology Branch of the Chinese Medical Association in 2014, the infant was regularly checked in our hospital. DIAGNOSIS: Optical coherence tomography (OCT) examination showed injuries of the photoreceptors and RPE in macular area. INTERVENTIONS: The fundus screening at 40 weeks' and 4 days' gestation (corrected gestational age) showed retinopathy of prematurity in bilateral eyes, with round yellow-white lesions at the macular area of right eye and sub-temporal macular area. OCT examination showed interrupted signals in the external limiting membrane (ELM), inner segment of the photoreceptors (IS)/outer segment of the photoreceptors (OS) layer, interdigitation zone (IZ), and RPE of the central fovea of macula of the right eye, with the area of defect of approximately 184 µm. Enhanced signal reflection was found under the defect area. Interrupted signals were also found in the IS/OS layer of the central fovea of macula of the left eye, with the area of defect of approximately 222 µm. Fundus fluorescence angiography (FFA) examination showed transmitted fluorescence at the macular area of the right eye and sub-temporal macular area of the left eye, suggesting retinopathy of prematurity in bilateral eyes. OUTCOMES: Several factors, such as photic damage, eye injuries, hyperpyrexia, and underlying diseases, could cause macular retinal injuries. However, the baby had not received any radiation from high energy intense light sources, and had no history of hyperpyrexia or trauma. Fundamental screening was performed 1 year and 4 months of age and no obvious change was found in the round yellow-white lesions of the eyes compared with that in earlier stages. We have contacted with the patient for the follow-up OCT and FFA examinations a month later to check the possible structural changes of the macular area. LESSONS: The retina of a preterm infant is underdeveloped, we speculated that the bilateral retinal injuries in this baby could be caused by various factors.

Nucleic acid hybridization on a plasmonic nanointerface of optical microfiber enables ultrahigh-sensitive detection and potential photothermal therapy.

Quantifying the microRNA (miRNA) level and manipulating them in complex samples, such as serum, is of intense interest because miRNAs are important diagnostic markers. Here, we demonstrate an optical microfiber integrating of untrasensitive detection function and local photothermal therapy potential. A nanointerface consisting of GO supported Cu2-xS nanoplates presented the localized surface plasmon resonance (LSPR) tuned to be consistent with the operation wavelength of the microfiber transducer. It enhanced the surface energy density of evanescent field, on which the miRNA sensing and therapy occurred. With evanescent field enhancement by the plasmonic nanointerface, the sensor exhibits an ultrahigh sensitivity for detecting microRNA at concentrations ranging from 0.1 aM to 10 pM. It is also capable of differentiating one-base mismatches of miRNA at ultralow concentrations (as low as 10 aM) in serum. The photothermal effect of nanointerface simultaneously endows the sensor with the potential for localized photothermal therapy. This work presents a possible approach for the in-situ integration of diagnosis and treatment in early stage.

An Optical Microfiber Biosensor for CEACAM5 Detection in Serum: Sensitization by a Nanosphere Interface.

The detection of carcinoembryonic antigen (CEA)-related cell adhesion molecules 5 (CEACAM5) is significant in cancer prewarning. Early diagnosis can effectively alleviate the danger of cancer. Point-of-care testing (POCT) has become a competitive technology for early detection. Fiber optic biosensors have great potential as POCT tools. However, their limits of detection (LODs) are not sufficient to afford ultralow concentration detection at the early stage. Herein, this work presents an optical microfiber sensor functionalized by a polystyrene@gold nanosphere (PS@Au nanosphere) interface for a synergistic sensitization effect to detect the ultralow CEACAM5 concentrations in serum at the early stage. The sensor's LOD achieves 3.54 × 10-17 M in pure solution and 5.27 × 10-16 M in serum, with the sensitization effect coupled with surface area enlargement and electromagnetic enhancement of interface. This LOD is about 6 orders of magnitude lower than that of current methods. It can be employed to detect the biomarkers at ultralow concentrations present in serum in the early stages of cancer. As the interfacial synergistic sensitization strategy is suitable for refractive index (RI)-based optical transducers, this work provides new opportunities to employ fiber optic biosensors as effective POCT tools.

Gulp1 controls Eph/ephrin trogocytosis and is important for cell rearrangements during development.

Trogocytosis, in which cells nibble away parts of neighboring cells, is an intercellular cannibalism process conserved from protozoa to mammals. Its underlying molecular mechanisms are not well understood and are likely distinct from phagocytosis, a process that clears entire cells. Bi-directional contact repulsion induced by Eph/ephrin signaling involves transfer of membrane patches and full-length Eph/ephrin protein complexes between opposing cells, resembling trogocytosis. Here, we show that the phagocytic adaptor protein Gulp1 regulates EphB/ephrinB trogocytosis to achieve efficient cell rearrangements of cultured cells and during embryonic development. Gulp1 mediates trogocytosis bi-directionally by dynamic engagement with EphB/ephrinB protein clusters in cooperation with the Rac-specific guanine nucleotide exchange factor Tiam2. Ultimately, Gulp1's presence at the Eph/ephrin cluster is a prerequisite for recruiting the endocytic GTPase dynamin. These results suggest that EphB/ephrinB trogocytosis, unlike other trogocytosis events, uses a phagocytosis-like mechanism to achieve efficient membrane scission and engulfment.