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Various applications would benefit from the ability to continuously measure biomolecules. Here the authors describe a biosensing technology based on the free diffusion of biofunctionalized particles hovering over a sensor surface, which enables monitoring of analytes (pM-µM) over long timespans.

Sulfur is an essential nutrient for plant growth and development. Sulfate transporters (Sultrs) are critical for sulfate (SO42-) uptake from the soil by the roots in higher plants. However, knowledge about Sultrs in apples (Malus domestica) is scarce. Here, nine putative MdSultrs were identified and classified into two groups according to the their phylogenetic relationships, gene structures, and conserved motifs. Various cis-regulatory elements related to abiotic stress and plant hormone responsiveness were found in the promoter regions of MdSultrs. These MdSultrs exhibited tissue-specific expression patterns and responded to low sulfur (S), abscisic acid (ABA), indole-3-acetic acid (IAA), and methyl jasmonate (MeJA), wherein MdSultr3;1a was especially expressed in the roots and induced by low S. The uptake of SO42- in cultivated apples depends on the roots of its rootstock, and MhSultr3;1a was isolated from Malus hupehensis roots used as a rootstock. MhSultr3;1a shared 99.85% homology with MdSultr3;1a and localized on the plasma membrane and nucleus membrane. Further function characterization revealed that MhSultr3;1a complemented an SO42- transport-deficient yeast mutant and improved the growth of yeast and apple calli under low S conditions. The MhSultr3;1a-overexpressing apple calli had a higher fresh weight compared with the wild type (WT) under a low-S treatment because of the increased SO42- and cysteine (Cys) content. These results demonstrate that MhSultr3;1a may increase the content of SO42- and Cys to meet the demands of S-containing compounds and improve their growth under S-limiting conditions.

The use of antibodies to capture and profile exosomes limits the number of target proteins that can be detected. Here the authors develop a proximity-dependent barcoding assay that allows profiling of 38 surface proteins on individual exosomes from heterogeneous samples such as serum and seminal fluid.

Biomarkers are natural indicators of some biological conditions, often used in diagnostics. Here, the authors developed a biosensor that continuously measures concentrations of DNA or protein biomarkers, and is based on particles that change mobility by directly interacting with individual molecules.

Abstract Detection and quantification of proteins and their post-translational modifications are crucial to decipher functions of complex protein networks in cell biology and medicine. Capillary isoelectric focusing together with antibody-based detection can resolve and identify proteins and their isoforms with modest sample input. However, insufficient sensitivity prevents detection of proteins present at low concentrations and antibody cross-reactivity results in unspecific detection that cannot be distinguished from bona fide protein isoforms. By using DNA-conjugated antibodies enhanced signals can be obtained via rolling circle amplification (RCA). Both sensitivity and specificity can be greatly improved in assays dependent on target recognition by pairs of antibodies using in situ proximity ligation assays (PLA). Here we applied these DNA-assisted RCA techniques in capillary isoelectric focusing to resolve endogenous signaling transducers and isoforms along vascular endothelial growth factor (VEGF) signaling pathways at concentrations too low to be detected in standard assays. We also demonstrate background rejection and enhanced specificity when protein detection depended on binding by pairs of antibodies using in situ PLA, compared to assays where each antibody preparation was used on its own.

Extracellular vesicles (EVs) derived from blood cells are promising biomarkers for various diseases. However, they are difficult to measure accurately in plasma due to their small size. Here, we demonstrate that platelet-derived EVs in plasma can be measured using solid-phase proximity ligation assay with high sensitivity and specificity using very small sample volume of biological materials. The results correlate well with high-sensitivity flow cytometry with the difference that the smallest EVs are detected. Briefly, the EVs are first captured on a solid phase, using lactadherin binding, and detection requires recognition with two antibodies followed by qPCR. The assay, using cholera toxin subunit-B or lactadherin as capture agents, also allowed detection of the more rare population of tissue factor (TF)-positive EVs at a concentration similar to sensitive TF activity assays. Thus, this assay can detect different types of EVs with high specificity and sensitivity, and has the potential to be an attractive alternative to flow cytometric analysis of preclinical and clinical samples. Improved techniques for measuring EVs in plasma will hopefully contribute to the understanding of their role in several diseases.

The quality of DNA-labeled affinity probes is critical in DNA-assisted protein analyses, such as proximity ligation and extension assays, immuno-PCR, and immuno-rolling circle amplification reactions. Efficient, high-performance methods are therefore required for isolation of pure conjugates from reactions where DNA strands have been coupled to antibodies or recombinant affinity reagents. Here we describe a universal, scalable approach for preparing high-quality oligonucleotide-protein conjugates by sequentially removing any unconjugated affinity reagents and remaining free oligonucleotides from conjugation reactions. We applied the approach to generate high-quality probes using either antibodies or recombinant affinity reagents. The purified high-grade probes were used in proximity ligation assays in solution and in situ, demonstrating both augmented assay sensitivity and improved signal-to-noise ratios.

Objective To explore the causes and nursing strategies of red blood cell spillage in apheresis platelet donors, so as to avoid adverse reactions to blood donation and platelet discarding and improve blood donation services. Methods A nursing flowchart for red blood cell spillage was developed based on literature. One case of red blood cell spillage in a apheresis platelet donor as attached, and corresponding literature review was conducted. Results After the nursing intervention through the nursing flowchart of red cell spillage, platelet apheresis was successfully conducted. The donor felt good and did not experience any adverse reaction to blood donation, and with no more red blood cell spillage. By reviewing relevant literature, the incidence, principles, causes, treatments, prevention of adverse reactions to blood donation and psychological care methods of red blood cell spillage were systematically summarized. Conclusion Red blood cell spillage in apheresis platelet donors occurs occasionally, and a flowchart of care for red blood cell spillage can help blood station staff quickly identify the cause and handle it correctly to avoid mishandling whicn can result in adverse reactions or discarding of platelets.

Abstract Objective To investigate the characteristics of different Acute Gastrointestinal Injury (AGI) grading trajectories and examine their impact on prognosis in the Pediatric Intensive Care Unit (PICU). Methods This retrospective cohort study was conducted at a large children’s hospital in China. The children admitted to the PICU were included. AGI grade was assessed every other day during the initial nine days following PICU admission. Results A total of 642 children were included, of which 364 children (56.7%) exhibited varying degrees of gastrointestinal dysfunction (AGI grade ≥ 2). Based on the patterns of AGI grading over time, six groups were identified: low-stable group, low-fluctuating group, medium-decreasing group, medium-increasing group, high-decreasing group, high-persistent group. The high-persistent group accounted for approximately 90% of all recorded deaths. Compared to low-stable group, both the medium-increasing and high-persistent groups exhibited positive correlations with length of stay in PICU (PICU LOS) and length of stay (LOS). Compared to low-stable group, the five groups exhibited a negative correlation with the percentage of energy received by enteral nutrition (EN), as well as the protein received by EN. Conclusion This study identified six distinct trajectory groups of AGI grade in critically ill children. The pattern of AGI grade trajectories over time were associated with EN delivery proportions and clinical outcomes.

Objective This study endeavors to introduce the statistical process control (SPC) method to analyze the quality control index concerning red blood cells in additive solution with leukocytes reduced, with the aspiration to advance the effective utilization of blood quality control data, thereby providing empirical foundations for the continual enhancement of blood quality. Methods Between 2020 and 2022, test data pertaining to the quality control index of red blood cells in additive solution with leukocytes reduced were amassed from six blood stations in Chongqing area. Utilizing Minitab software, the SPC analysis was carried out, p-control charts were delineated, the non-conformance rates of each quality control index along with their 95% confidence intervals were computed, as well as the Process Capability Index (Z value). Results In accordance with the Whole Blood and Blood Components Quality Requirements, the appraisal of the quality control indexes for red blood cells in additive solution with leukocytes reduced manifested a conformity rate of 100% for appearance, end-of-storage hemolysis rate and sterility test. Nonetheless, the conformity rates for volume, hemoglobin, hematocrit and residual leukocytes did not attain 100%, albeit all were ≥75%. Through the employment of binomial distribution-based p-control charts, the controlled state of the production process was discerned. Although the overarching conformity rate satisfied the national standard stipulations, it was discerned that there were out-of-control points concerning volume, hemoglobin, hematocrit, and residual leukocytes across different institutions, exhibiting palpable trends. The non-conformance rates of all quality control indexes were less than 25%, yet at a 95% confidence level, the residual leukocyte counts from institutions B, C, E, and F did not adhere to the stipulations (exceeding 25%). By architecting the ability evaluation index Z value for count data process capability analysis, it was unveiled that the volume of institution E, the hematocrit of institutions B, C, and F, and the residual leukocytes Z values of all six blood collection and supply institutions were below 2, hinting at avenues for amelioration. Conclusion The SPC method anchored in binomial distribution exhibits substantial application merit in blood component quality management, facilitating real-time surveillance of blood collection, preparation, and storage procedures.

PurposeThis study aimed to clarify the effect of early glucocorticoid (GC) application on achieving minimal manifestation (MM) status or better in the treatment of myasthenia gravis (MG) in the early clinical phase.MethodsA retrospective analysis was performed using data from 336 patients with MG who received GC therapy from January 2015 to September 2022 in the Zhengzhou University Henan Institute of Medical and Pharmaceutical Sciences Myasthenia Gravis Biobank (ZMB). Patients were divided into two groups: the early mono-GC group (treated with GC within 6 months of MG onset) and the delayed mono-GC group.ResultsKaplan–Meier analysis showed that the early mono-GC group achieved MM status earlier and more frequently than the delayed mono-GC group (log-rank test, p = 0.0082; hazard ratio [HR], 1.66; p = 0.011). The early mono-GC group had a lower maintenance oral GC dose than the delayed mono-GC group. In multivariate Cox regression analysis, early mono-GC (HR, 1.50; p = 0.043), early-onset MG (EOMG) (HR, 1.74; p = 0.034), and ocular MG (OMG) (HR, 1.90; p = 0.007) were associated with MM status or better. In conclusion, early mono-GC, EOMG, and OMG were positive predictors of treatment goals. In EOMG, OMG, and acetylcholine receptor antibody-positive MG (AChR-MG) subgroups, the maintenance oral GC doses in the early mono-GC group were significantly lower than the doses in the delayed mono-GC group (p < 0.05).ConclusionEarly intervention with GC led to better long-term outcomes and reduced the necessary maintenance dose of oral GC for patients with MG. EOMG and OMG were positive predictors of MM status or better with mono-GC.

Variations in different urinary measurements for evaluating iodine status are concerning to clinicians and researchers. The present study aimed to analyze the interindividual and intraindividual variations in the urinary iodine concentration (UIC) and urinary iodine/creatinine (UI/Cr) ratio and evaluate their application in assessing the iodine nutrition of preschool children. Four repeated spot urine samples were collected from 163 children at different times within one day. The urinary iodine concentration (UIC) and urinary creatinine concentration (UCr) were measured, and the UI/Cr ratio was calculated. The UIC (P

Myasthenia gravis (MG) is characterized by autoimmune damage to the postsynaptic membrane of the neuromuscular junction (NMJ) with impaired postsynaptic acetylcholine receptor (AChR) aggregation. Low-density lipoprotein receptor-related protein 4 (LRP4) plays an important role in AChR aggregation at endplate membranes via the Agrin–LRP4–muscle-specific receptor tyrosine kinase (MuSK) cascade. Sorting nexin 17 (SNX17) regulates the degradation and recycling of various internalized membrane proteins. However, whether SNX17 regulates LRP4 remains unclear. Therefore, we examined the regulatory effects of SNX17 on LRP4 and its influence on AChR aggregation in MG. We selected C2C12 myotubes and induced LRP4 internalization via stimulation with anti-LRP4 antibody and confirmed intracellular interaction between SNX17 and LRP4. SNX17 knockdown and overexpression confirmed that SNX17 promoted MuSK phosphorylation and AChR aggregation by increasing cell surface LRP4 expression. By establishing experimental autoimmune MG (EAMG) mouse models, we identified that SNX17 upregulation improved fragmentation of the AChR structure at the NMJ and alleviated leg weakness in EAMG mice. Thus, these results reveal that SNX17 may be a novel target for future MG therapy.

Healthcare is in demand of technologies for real-time sensing in order to continuously guard the state of patients. Here we present biomarker-monitoring based on the sensing of particle mobility, a concept wherein particles are coupled to a substrate via a flexible molecular tether, with both the particles and substrate provided with affinity molecules for effectuating specific and reversible interactions. Single-molecular binding and unbinding events modulate the Brownian particle motion and the state changes are recorded using optical scattering microscopy. The technology is demonstrated with DNA and protein as model biomarkers, in buffer and in blood plasma, showing sensitivity to picomolar and nanomolar concentrations. The sensing principle is direct and self-contained, without consuming or producing any reactants. With its basis in reversible interactions and single-molecule resolution, we envisage that the presented technology will enable biosensors for continuous biomarker monitoring with high sensitivity, specificity, and accuracy. [ABSTRACT FROM AUTHOR]

Limited load capacity is the bottleneck for the practical application of mobile multi-joint legged robots. And improving the efficiency of the drive system is a key factor in improving the load capacity. To improve the efficiency of mobile robots, in this paper, a new kind of actuator that imitates the driving mechanism of human muscles is innovatively designed and validated through experiments. The proposed actuator consists of a single power source and multiple plunger pistons, and imitates the configuration of a human muscle, to improve the efficiency and load capacities. The design proposed here represents a new class of driving methods. The actuator selects the most appropriate combination of the effective areas of plunger pistons like the human muscles, to ensure that the maximal output force aligns with the load force. To validate that the new actuator can improve the efficiency of hydraulic systems of mobile robots, a robotic arm incorporating a prototype of the new actuator was designed. The proposed system was validated through a series of experiments. The experiments show that the bionic actuator can adjust the flow rate of the system input by adjusting the number and size of the motion units involved in the work, and with the change in load force, it changes the output force by recruiting different motion units, which indicates good controllability. The results reported herein reveal that the application of bionics to the design of robotic actuator can significantly improve the efficiency and overall performance of the robots, and this biomimetic approach can be applied to a variety of robots.

The high energy efficiency and lightweight are recent trends in mobile hydraulics. In this paper, a new energy-saving fluid power converter (FPC) is designed to solve the problem of low energy conversion efficiency in hydraulic systems with variable load. The FPC is a kind of hydraulic transformer, it is similar to the DC transformer in working principle. Pulse width modulation (PWM) signal is used to control the high-speed on-off valves, and the high-speed on-off valve can switch supply ports between different pressure oil sources to achieve the adjustment of the FPC's output. The FPC's mathematical principle is analyzed in this paper, the influence of the friction between the inertial mass and the conversion cylinder on the system efficiency is studied. The influence of the PWM signal frequency, conversion cylinder cross-sectional area and inertial mass on the characteristics of FPC system is deduced. The results of the analysis are validated by Matlab/Simulink, and suggestions of selecting the design parameters of FPC are provided.

In order to improve the interface experience effect of the mobile terminal software, this paper improves the UI design by combining computer image processing technology and improves the diffusion algorithm for images by improving the diffusion model, improving the diffusion coefficient and adaptively selecting the diffusion threshold. Moreover, this paper has carried out deep research on coordinate transformation and image interpolation and stored the result of coordinate transformation in the coordinate transformation table and weight table. In addition, this paper proposes an improved digital scan conversion method based on a lookup table and constructs an improved UI design system model. Through the analysis of experimental data, it can be seen that the application effect of computer image processing technology in UI design is very good, and it can effectively promote the improvement of UI design technology.

This study aimed to establish a cell-based assay (CBA) for the detection of agrin antibodies (Agrin-Ab) to explore the clinical features of agrin antibody-positive Chinese patients with myasthenia gravis (Agrin-MG). We developed a CBA based on the human full-length agrin protein expressed in HEK293T cells for the reliable and efficient detection of Agrin-Ab. Clinical data and serum samples were collected from 1948 MG patients in 26 provinces in China. The demographic and clinical features of Agrin-MG patients were compared with those of other MG patient subsets. Eighteen Agrin-MG cases were identified from 1948 MG patients. Nine patients were Agrin-Ab positive, and nine were AChR-Ab and Agrin-Ab double-positive (Agrin/AChR-MG). Eleven (61.11%) patients were males older than 40 years of age. The initial symptom in 13 (81.25%) cases was ocular weakness. Occasionally, the initial symptom was limb-girdle weakness (two cases) or bulbar muscle weakness (one case). Agrin-MG patients demonstrated slight improvement following treatment with either acetylcholinesterase inhibitor or prednisone; however, the combination of the two drugs could effectively relieve MG symptoms. In China, Agrin-MG demonstrated seropositivity rates of 0.92%. These patients were commonly middle-aged or elderly men. The patients usually presented weakness in the ocular, bulbar, and limb muscles, which may be combined with thymoma. These patients have more severe diseases, although the combination of pyridostigmine and prednisone was usually effective in relieving symptoms.

Better and more efficient use of biomass energy is seen as a favourable option for reducing carbon emissions. Biomass pellet fuel is one of the most common and important ways of utilising biomass energy. The use of diverse biomass resources with different properties for pelletizing is a current research hotspot. This paper provides an innovative overview of co-pelletization technology for biomass pellet fuels. The chemical composition of various types of biomass is classified and the influence of different biomass matrix feedstocks and pelletizing operating parameters on pellet quality and pelletizing process is summarized. The research results indicate that the natural chemical fraction of biomass has a significant influence on the pelletizing process and fuel quality. Furthermore, co-pelletizing can be divided into biomass-biomass co-pelletizing and biomass-non-biomass co-pelletizing. Common co-pelleting combinations include: woody and herbaceous crop co-pelleting; woody or herbaceous crops with high starch and oil content (e.g. microalgae, peanut shells, etc.); mixed pelleting of different parts of the same crop (e.g. bark and leaves of the same quality); co-pelleting of biomass with solid waste (e.g. municipal sludge, waste paper, etc.). Crop types such as oil and sugar used for co-pelletizing with herbaceous and woody crops help to reduce energy consumption in the preparation of biomass pellet fuel and improve the quality of the pellets. Co-pelletization of non-biomass-based materials (domestic production waste, inorganic additives) with biomass also facilitates the pelletizing process and improves the quality of pellet fuel. It is obvious that mixing different raw materials for co-pelletizing is considered a promising way for upgrading biomass pellet and that economical, environmentally friendly and sustainable raw materials are prerequisites for co-pelletizing. Moreover, co-pelletizing seems to be a strong option for enhancing the competitiveness of biomass pellet fuel production at scale in the future.