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Pathogenic bacterial infections and drug resistance make it urgent to develop new antibacterial agents with targeted delivery. Here, a new targeting delivery nanosystem is designed based on the potential interaction between bacterial recognizing receptors on macrophage membranes and distinct pathogen‐associated molecular patterns in bacteria. Interestingly, the expression of recognizing receptors on macrophage membranes increases significantly when cultured with specific bacteria. Therefore, by coating pretreated macrophage membrane onto the surface of a gold–silver nanocage (GSNC), the nanosystem targets bacteria more efficiently. Previously, it has been shown that GSNC alone can serve as an effective antibacterial agent owing to its photothermal effect under near‐infrared (NIR) laser irradiation. Furthermore, the nanocage can be utilized as a delivery vehicle for antibacterial drugs since the gold–silver nanocage presents a hollow interior and porous wall structure. With significantly improved bacterial adherence, the Sa‐M‐GSNC nanosystem, developed within this study, is effectively delivered and retained at the infection site both via local or systemic injections; the system also shows greatly prolonged blood circulation time and excellent biocompatibility. The present work described here is the first to utilize bacterial pretreated macrophage membrane receptors in a nanosystem to achieve specific bacterial‐targeted delivery, and provides inspiration for future therapy based on this concept.

No abstract

Titanium implants have been widely used in bone tissue engineering for decades. However, orthopedic implant-associated infections increase the risk of implant failure and even lead to amputation in severe cases. Although TiO2 has photocatalytic activity to produce reactive oxygen species (ROS), the recombination of generated electrons and holes limits its antibacterial ability. Here, we describe a graphdiyne (GDY) composite TiO2 nanofiber that combats implant infections through enhanced photocatalysis and prolonged antibacterial ability. In addition, GDY-modified TiO2 nanofibers exert superior biocompatibility and osteoinductive abilities for cell adhesion and differentiation, thus contributing to the bone tissue regeneration process in drug-resistant bacteria-induced implant infection.

The widespread application of sophisticated structural health monitoring systems in civil infrastructures produces a large volume of data. As a result, the analysis and mining of structural health monitoring data have become hot research topics in the field of civil engineering. However, the harsh environment of civil structures causes the data measured by structural health monitoring systems to be contaminated by multiple anomalies, which seriously affect the data analysis results. This is one of the main barriers to automatic real-time warning, because it is difficult to distinguish the anomalies caused by structural damage from those related to incorrect data. Existing methods for data cleansing mainly focus on noise filtering, whereas the detection of incorrect data requires expertise and is very time-consuming. Inspired by the real-world manual inspection process, this article proposes a computer vision and deep learning–based data anomaly detection method. In particular, the framework of the proposed method includes two steps: data conversion by data visualization, and the construction and training of deep neural networks for anomaly classification. This process imitates human biological vision and logical thinking. In the data visualization step, the time series signals are transformed into image vectors that are plotted piecewise in grayscale images. In the second step, a training dataset consisting of randomly selected and manually labeled image vectors is input into a deep neural network or a cluster of deep neural networks, which are trained via techniques termed stacked autoencoders and greedy layer-wise training. The trained deep neural networks can be used to detect potential anomalies in large amounts of unchecked structural health monitoring data. To illustrate the training procedure and validate the performance of the proposed method, acceleration data from the structural health monitoring system of a real long-span bridge in China are employed. The results show that the multi-pattern anomalies of the data can be automatically detected with high accuracy.

Platelet rich fibrin (PRF) has been utilized clinically as a platelet concentrate capable of stimulating tissue regeneration. Interestingly, several protocols have been proposed with little data obtained regarding the final cell counts following centrifugation. The aim of the present study was to compare different commercially available centrifuges and their respective protocols utilizing a novel method to quantify cells. One millimeter blood layers following centrifugation were sequentially pipetted from the upper layer downward until all 10 mL were harvested in sequential samples. Thereafter, each sample was sent for CBC analysis to accurately quantify precisely cell numbers within each separate blood layer following centrifugation. The results from this study revealed that L-PRF protocols (2700 rpm × 12 min) produced a clot with the majority of platelets and leukocytes concentrated within the buffy coat with relatively no cells found within the first 4 mL of L-PRF. Slower centrifugation protocols produced using the A-PRF protocols (1300 rpm × 8 min) produced a more evenly distributed number of platelets throughout PRF. Injectable-PRF (i-PRF) protocols produced the highest concentration of leukocytes/platelets, however, the total number of leukocytes and platelets were significantly lower owing to the decreased total volume collected. Horizontal centrifugation produced a significant increase in both the number and concentration of platelets and leukocytes (up to 3.5× higher for either solid/liquid PRF). When compared to either fixed or angled centrifuge (InstraSpin, Process for PRF). In conclusion, the present study revealed a novel/accurate method to quantify cells following PRF protocols. Furthermore, PRF produced via horizontal centrifugation accumulated a higher number and concentration of platelets/leukocytes when compared to either fixed-angle centrifugation. K E Y W O R D S blood platelets, centrifugation, fibrin, platelet rich fibrin

Delivery of monoclonal antibody therapeutics across the blood-brain barrier is an obstacle to the diagnosis or therapy of CNS disease with antibody drugs. The immune therapy of Alzheimer's disease attempts to disaggregate the amyloid plaque of Alzheimer's disease with an anti-Abeta monoclonal antibody. The present work is based on a three-step model of immune therapy of Alzheimer's disease: (1) influx of the anti-Abeta monoclonal antibody across the blood-brain barrier in the blood to brain direction, (2) binding and disaggregation of Abeta fibrils in brain, and (3) efflux of the anti-Abeta monoclonal antibody across the blood-brain barrier in the brain to blood direction. This is accomplished with the genetic engineering of a trifunctional fusion antibody that binds (1) the human insulin receptor, which mediates the influx from blood to brain across the blood-brain barrier, (2) the Abeta fibril to disaggregate amyloid plaque, and (3) the Fc receptor, which mediates the efflux from brain to blood across the blood-brain barrier. This fusion protein is a new antibody-based therapeutic for Alzheimer's disease that is specifically engineered to cross the human blood-brain barrier in both directions.

Mucopolysaccharidosis Type I, Hurler's Syndrome, is a lysosomal storage disorder that affects the brain. The missing enzyme, alpha-L-iduronidase (IDUA), does not cross the blood-brain barrier (BBB). To enable BBB transport of the enzyme, human IDUA was fused to the carboxyl terminus of the heavy chain of a chimeric monoclonal antibody (MAb) to the human insulin receptor (HIR). The HIRMAb crosses the BBB on the endogenous insulin receptor, and acts as a molecular Trojan horse to ferry into brain the IDUA. Transfection of COS cells resulted in high levels of IDUA enzyme activity both in the medium and in the intracellular space. The size of the fusion heavy chain, as measured with Western blotting and antibodies to either human IDUA or human IgG, was increased about 80 kDa, relative to the size of the heavy chain of the parent HIRMAb. The IDUA enzyme specific activity of the affinity purified HIRMAb-IDUA fusion protein was 363 +/- 37 U/microg protein, which is comparable to specific activity of recombinant IDUA. The accumulation of glycosoaminoglycans in Hurler fibroblasts was decreased 70% by treatment with the HIRMAb-IDUA fusion protein. Confocal microscopy showed targeting of the fusion protein to the lysosome. The HIRMAb-IDUA fusion protein bound with high affinity to the HIR, and was rapidly transported into the brain of the adult Rhesus monkey following intravenous administration. The HIRMAb-IDUA fusion protein is a new treatment for Hurler's syndrome, which has been specifically engineered to cross the human BBB.