Chemodynamic therapy (CDT) uses the tumor microenvironment‐assisted intratumoral Fenton reaction for generating highly toxic hydroxyl free radicals (•OH) to achieve selective tumor treatment. ...However, the limited intratumoral Fenton reaction efficiency restricts the therapeutic efficacy of CDT. Recent years have witnessed the impressive development of various strategies to increase the efficiency of intratumoral Fenton reaction. The introduction of these reinforcement strategies can dramatically improve the treatment efficiency of CDT and further promote the development of enhanced CDT (ECDT)‐based multimodal anticancer treatments. In this review, the authors systematically introduce these reinforcement strategies, from their basic working principles, reinforcement mechanisms to their representative clinical applications. Then, ECDT‐based multimodal anticancer therapy is discussed, including how to integrate these emerging Fenton reinforcement strategies for accelerating the development of multimodal anticancer therapy, as well as the synergistic mechanisms of ECDT and other treatment methods. Eventually, future direction and challenges of ECDT and ECDT‐based multimodal synergistic therapies are elaborated, highlighting the key scientific problems and unsolved technical bottlenecks to facilitate clinical translation.
The advances in reinforcement strategies to increase the efficiency of intratumoral Fenton reaction are discussed. Then, multimodal anticancer therapies involving enhanced chemodynamic therapy and mechanisms of synergy are highlighted. Finally, the major challenges and further improvements of this evolving field are elaborated.
Exploring and understanding biological and pathological changes are of great significance for early diagnosis and therapy of diseases. Optical sensing and imaging approaches have experienced major ...progress in this field. Particularly, an emergence of various functional optical nanoprobes has provided enhanced sensitivity, specificity, targeting ability, as well as multiplexing and multimodal capabilities due to improvements in their intrinsic physicochemical and optical properties. However, one of the biggest challenges of conventional optical nanoprobes is their absolute intensity-dependent signal readout, which causes inaccurate sensing and imaging results due to the presence of various analyte-independent factors that can cause fluctuations in their absolute signal intensity. Ratiometric measurements provide built-in self-calibration for signal correction, enabling more sensitive and reliable detection. Optimizing nanoprobe designs with ratiometric strategies can surmount many of the limitations encountered by traditional optical nanoprobes. This review first elaborates upon existing optical nanoprobes that exploit ratiometric measurements for improved sensing and imaging, including fluorescence, surface enhanced Raman scattering (SERS), and photoacoustic nanoprobes. Next, a thorough discussion is provided on design strategies for these nanoprobes, and their potential biomedical applications for targeting specific biomolecule populations (
e.g.
cancer biomarkers and small molecules with physiological relevance), for imaging the tumor microenvironment (
e.g.
pH, reactive oxygen species, hypoxia, enzyme and metal ions), as well as for intraoperative image guidance of tumor-resection procedures.
Conventional optical nanoprobes rely on absolute intensity-dependent signal readout, which can often cause erroneous sensing and imaging results owing to the existence of analyte-independent confounding factors. Ratiometric signal processing provides built-in self-calibration for signal correction, enabling more accurate molecular detection and imaging.
Chemical contamination in food is one of the most serious food safety problems. Competitive enzyme-linked immunosorbent assay (Cp-ELISA) is the most widely used analytical tool for detection of food ...chemical contaminants due to its high throughput, low cost, and straightforward readouts. However, conventional ELISA suffers from low sensitivity, which greatly limits its potential in highly sensitive detection. To fulfill increasingly stringent control requirement for chemical contaminants in food, improving the sensitivity of Cp-ELISA is important and meaningful. In this paper, we will briefly review various emerging strategies for increasing Cp-ELISA sensitivity, including: 1) screening higher affinity antibodies to target antigens; 2) preparing competing antigens with lower affinity to antibodies; 3) employing signal amplification; and 4) introducing novel signal transducer elements. This review will focus on clarifying the underlying mechanisms of these strategies in improving sensitivity and providing a careful comparison. Brief discussion on challenges and future directions will be elaborated.
•Emerging strategies for improving the detection sensitivity of competitive ELISA was systematically reviewed.•Three core elements of antibodies, competing antigens and signal transducers in competitive ELISA were highlighted.•Typical applications for food chemical contamination detection were selected.•This work perhaps stimulates an extensive and deep research in this field.
Conversion of agricultural lands to urban uses affects regional and global climate not only through the release of greenhouse gases but also through altering land surface physical processes such as ...energy and water balances. Most existing studies on the meteorological impacts of urbanization focus on urban heat island effects with little attention on its impacts of atmospheric humidity, a key variable in hydrometeorology and climate science. We define the influences of urbanization on reducing atmospheric humidity and elevating vapor pressure deficit as urban dry island (UDI) effects. We conduct a case study in the Yangtze River Delta, a typical humid area in southern China that is under rapid urbanization. We examine spatiotemporal characteristics of UDI and identify potential drivers during 2001–2014. Relationships and interactions between variations of air temperature, atmospheric humidity, evapotranspiration, and leaf area index of different land cover were determined using correlation and attribution analyses at both station and regional levels. We show that atmospheric humidity decreased dramatically and vapor pressure deficit increased sharply in the urban core, resulting in enhanced UDI. In addition to global warming and localized urban heat island, UDI is closely related to the loss of vegetation cover (i.e., natural wetlands and paddies). Reduction of evapotranspiration or latent heat is another important factor contributing to UDI effects. We conclude that the role of vegetated land cover and associated ecohydrological processes in moderating UDI and maintaining a stable climate and environment should be considered in massive urban planning and global change impact assessment in southern China.
Key Points
Proposed urban dry island (UDI) to characterize urbanization effects on reducing atmospheric humidity and elevating vapor pressure deficit
Enhanced UDI effects are explained by feedback of the ecohydrological cycle to urban land cover change
Urban heat island and UDI effects are coupled and should be collectively addressed in urban planning and climate change assessment
Herein, we synthesized bifunctional magnetic fluorescent beads (MFBs) with a distinct core/shell structure by encapsulating octadecylamine-coated CdSe/ZnS QDs (OC-QDs) and oleic acid-modified iron ...oxide nanoparticles (OA-IONPs) into two polymer matrixes with different hydrophobic properties. The OC-QDs and OA-IONPs were mainly distributed in the outer layer of MFBs. The resultant MFBs displayed ca. 226-fold stronger fluorescence emission relative to the corresponding OC-QDs and retained ca. 45.4% of the saturation magnetization of the OA-IONPs. The MFBs were used to purify and enrich aflatoxin B1 (AFB1) from dark soy sauce and then utilized as a fluorescent reporter of immunochromatographic assay (ICA) for the sensitive detection of AFB1. Under the optimal detection conditions, the MFB-based ICA (MFB-ICA) displayed a dynamic linear detection of AFB1 in sauce extract over the range of 5–150 pg/mL with a half maximal inhibitory concentration of 27 ± 3 pg/mL (n = 3). The detection limits for AFB1 in sauce extract and real dark soy sauce were 3 and 51 pg/mL, respectively, which are considerably better than those of the previously reported fluorescent bead-based ICA methods. The analytical performance of the proposed MFB-ICA in terms of selectivity and accuracy was investigated by analyzing AFB1-spiked dark soy sauce samples. The reliability of the proposed method was further confirmed by ultraperformance liquid chromatography with fluorescence detection. With the combined advantages of QDs and IONPs, the resultant MFBs offer great potential as reporters of ICA for the sensitive detection of trace pollutants in complex matrix samples.
Support Vector Machine Classifier With Pinball Loss Xiaolin Huang; Lei Shi; Suykens, Johan A. K.
IEEE transactions on pattern analysis and machine intelligence,
05/2014, Letnik:
36, Številka:
5
Journal Article
Recenzirano
Traditionally, the hinge loss is used to construct support vector machine (SVM) classifiers. The hinge loss is related to the shortest distance between sets and the corresponding classifier is hence ...sensitive to noise and unstable for re-sampling. In contrast, the pinball loss is related to the quantile distance and the result is less sensitive. The pinball loss has been deeply studied and widely applied in regression but it has not been used for classification. In this paper, we propose a SVM classifier with the pinball loss, called pin-SVM, and investigate its properties, including noise insensitivity, robustness, and misclassification error. Besides, insensitive zone is applied to the pin-SVM for a sparse model. Compared to the SVM with the hinge loss, the proposed pin-SVM has the same computational complexity and enjoys noise insensitivity and re-sampling stability.
Coronavirus disease 2019 (COVID‐19) is a global pandemic that has caused severe health threats and fatalities in almost all communities. Studies have detected severe acute respiratory syndrome ...coronavirus 2 (SARS‐CoV‐2) in saliva with a viral load that lasts for a long period. However, researchers are yet to establish whether SARS‐CoV‐2 can directly enter the salivary glands. Therefore, this study aimed to assess the presence of angiotensin‐converting enzyme 2 (ACE2)/transmembrane serine proteases 2 (TMPRSS2) expression in salivary glands using publicly available databases. The distribution of ACE2 and TMPRSSs family in salivary gland tissue and other tissues was analyzed. The Genotype‐Tissue Expression dataset was employed to explore the ACE2 and TMPRSS2 expression in various body organs and salivary glands in a healthy population. The single‐cell sequencing data for salivary gland samples (including submandibular salivary gland and parotid gland) from mice were collected and analyzed. The components and proportions of salivary gland cells expressing the key protease TMPRSSs family were analyzed. Transcriptome data analysis showed that ACE2 and TMPRSS2 were expressed in salivary glands. The expression levels of ACE2 and TMPRSS2 were marginal without significant differences in different age groups or between men and women. Single‐cell RNA sequence analysis indicated that TMPRSS2 was mainly expressed in salivary gland epithelial cells. We speculate that SARS‐CoV‐2 may be entered in salivary glands.
Highlights
Our research found that human salivary glands have a host cell receptor for SARS‐CoV‐2. This implies that the virus might gain entry into the salivary glands. However, the underlying mechanism remains unclear and should further be explored.
In this paper, we propose a novel matching based tracker by investigating the relationship between template matching and the recent popular correlation filter based trackers (CFTs). Compared to the ...correlation operation in CFTs, a sophisticated similarity metric termed mutual buddies similarity is proposed to exploit the relationship of multiple reciprocal nearest neighbors for target matching. By doing so, our tracker obtains powerful discriminative ability on distinguishing target and background as demonstrated by both empirical and theoretical analyses. Besides, instead of utilizing single template with the improper updating scheme in CFTs, we design a novel online template updating strategy named memory, which aims to select a certain amount of representative and reliable tracking results in history to construct the current stable and expressive template set. This scheme is beneficial for the proposed tracker to comprehensively understand the target appearance variations, recall some stable results. Both qualitative and quantitative evaluations on two benchmarks suggest that the proposed tracking method performs favorably against some recently developed CFTs and other competitive trackers.
Highly luminescent quantum dot beads (QBs) were synthesized by encapsulating CdSe/ZnS and used for the first time as immunochromatographic assay (ICA) signal amplification probe for ultrasensitive ...detection of aflatoxin B1 (AFB1) in maize. The challenges to using high brightness QBs as probes for ICA are smooth flow of QBs and nonspecific binding on nitrocellulose (NC) membrane, which are overcome by unique polymer encapsulation of quantum dots (QDs) and surface blocking method. Under optimal conditions, the QB-based ICA (QB-ICA) sensor exhibited dynamic linear detection of AFB1 in maize extract from 5 to 60 pg mL–1, with a median inhibitory concentration (IC50) of 13.87 ± 0.16 pg mL–1, that is significantly (39-fold) lower than those of the QD as a signal probe (IC50 = 0.54 ± 0.06 ng mL–1). The limit of detection (LOD) for AFB1 using QB-ICA sensor was 0.42 pg mL–1 in maize extract, which is approximately 2 orders of magnitude better than those of previously reported gold nanoparticle based immunochromatographic assay (AuNP-ICA) and is even comparable with or better than the conventional enzyme-linked immunosorbent assay (ELISA) method. The performance and practicability of our QB-ICA sensor were validated with a commercial ELISA kit and further confirmed with liquid chromatography tandem mass spectrometry (LC–MS/MS). Given its efficient signal amplification performance, the proposed QB-ICA offers great potential for rapid, sensitive, and cost-effective quantitative detection of analytes in food safety monitoring.
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