Ion-Selective Transport Promotion Enabled by Angstrom-Scale Nanochannels in Dendrimer-Assembled Polyamide Nanofilm for Efficient Electrodialysis.

The ion permeability and selectivity of membranes are crucial in nanofluidic behavior, impacting industries ranging from traditional to advanced manufacturing. Herein, we demonstrate the engineering of ion-conductive membranes featuring angstrom-scale ion-transport channels by introducing ionic polyamidoamine (PAMAM) dendrimers for ion separation. The exterior quaternary ammonium-rich structure contributes to significant electrostatic charge exclusion due to enhanced local charge density; the interior protoplasmic channels of PAMAM dendrimer are assembled to provide additional degrees of free volume. This facilitates the monovalent ion transfer while maintaining continuity and efficient ion screening. The dendrimer-assembled hybrid membrane achieves high monovalent ion permeance of 2.81 mol m-2 h-1 (K+), reaching excellent mono/multivalent selectivity up to 20.1 (K+/Mg2+) and surpassing the permselectivities of state-of-the-art membranes. Both experimental results and simulating calculations suggest that the impressive ion selectivity arises from the significant disparity in transport energy barrier between mono/multivalent ions, induced by the "exterior-interior" synergistic effects of bifunctional membrane channels.

Versatile Platinum Nanoparticles-Decorated Phage Nanozyme Integrating Recognition, Bacteriolysis, and Catalysis Capabilities for On-Site Detection of Foodborne Pathogenic Strains Vitality Based on Bioluminescence/Pressure Dual-Mode Bioassay.

Sensitive and on-site discrimination of live and dead foodborne pathogenic strains remains a significant challenge due to the lack of appropriate assay and signal probes. In this work, a versatile platinum nanoparticle-decorated phage nanozyme (P2@PtNPs) that integrated recognition, bacteriolysis, and catalysis was designed to establish the bioluminescence/pressure dual-mode bioassay for on-site determination of the vitality of foodborne pathogenic strains. Benefiting from the bacterial strain-level specificity of phage, the target Salmonella typhimurium (S.T) was specially captured to form sandwich complexes with P2@PtNPs on another phage-modified glass microbead (GM@P1). As the other part of the P2@PtNPs nanozyme, the introduced PtNPs could not only catalyze the decomposition of hydrogen peroxide to generate a significant oxygen pressure signal but also produce hydroxyl radicals around the target bacteria to enhance the bacteriolysis of phage and adenosine triphosphate release. It significantly improved the bioluminescence signal. The two signals corresponded to the total and live target bacteria counts, so the dead target could be easily calculated from the difference between the total and live target bacteria counts. Meanwhile, the vitality of S.T was realized according to the ratio of live and total S.T. Under optimal conditions, the application range of this proposed bioassay for bacterial vitality was 102-107 CFU/mL, with a limit of detections for total and live S.T of 30 CFU/mL and 40 CFU/mL, respectively. This work provides an innovative and versatile nanozyme signal probe for the on-site determination of bacterial vitality for food safety.

Intelligent Biogenic Missile for Two-Photon Fluorescence Imaging-Guided Combined Photodynamic Therapy and Chemotherapy in Tumors.

Photodynamic therapy (PDT) is a significant noninvasive therapeutic modality, but it is often limited in its application due to the restricted tissue penetration depth caused by the wavelength limitations of the light source. Two-photon (TP) fluorescence techniques are capable of having an excitation wavelength in the NIR region by absorbing two NIR photons simultaneously, which offers the potential to achieve higher spatial resolution for deep tissue imaging. Thus, the adoption of TP fluorescence techniques affords several discernible benefits for photodynamic therapy. Organic TP dyes possess a high fluorescence quantum yield. However, the biocompatibility of organic TP dyes is poor, and the method of coating organic TP dyes with silica can effectively overcome the limitations. Herein, based on the TP silica nanoparticles, a functionalized intelligent biogenic missile TP-SiNPs-G4(TMPyP4)-dsDNA(DOX)-Aptamer (TGTDDA) was developed for effective TP bioimaging and synergistic targeted photodynamic therapy and chemotherapy in tumors. First, the Sgc8 aptamer was used to target the PTK7 receptor on the surface of tumor cells. Under two-photon light irradiation, the intelligent biogenic missile can be activated for TP fluorescence imaging to identify tumor cells and the photosensitizer assembled on the nanoparticle surface can be activated for photodynamic therapy. Additionally, this intelligent biogenic missile enables the controlled release of doxorubicin (DOX). The innovative strategy substantially enhances the targeted therapeutic effectiveness of cancer cells. The intelligent biogenic missile provides an effective method for the early detection and treatment of tumors, which has a good application prospect in the real-time high-sensitivity diagnosis and treatment of tumors.

Bioluminescence assay for rapid detection of live Staphylococcus aureus based on the enrichment of egg yolk antibody modified magnetic metal organic framework immunobeads.

Specific and rapid detection of live Staphylococcus aureus (S.A) in environmental and food samples is critically important for protecting human health. In order to fulfill this purpose, two kinds of novel egg yolk antibody (IgY) immobilized immunomagnetic beads (IMBs; mSiO2-IgY and mMOF-IgY), with core-shell mSiO2 and mMOF as substrate, were prepared for selectively enriching S.A from samples. Furthermore, the IMBs with captured S.A were collected and re-dissolved in 0.5 mL PBS. After that, a cotton swab coated with sodium dodecylsulfate (SDS) was put in the solution to lyse S.A cells and emit ATP bioluminescence of the luciferin/luciferase system. Finally, a portable bioluminescence detector was used for quantification of ATP corresponding to S.A concentration. The results demonstrated that mMOF-IgY can enrich more S.A than mSiO2-IgY and emit a stronger signal. The reasons may be due to the higher immobilization amount of IgY on the IMBs. Under optimal conditions, the calibration line of S.A concentration was 10-105 CFU mL-1 by mMOF-IgY within 30 min. The low detection limit of S.A was 3 CFU mL-1. The results demonstrated that the assay takes much shorter time than plate counting. Its portability and excellent detection capability are suitable for rapid monitoring of specific pathogens in foods.

Effects of clinical nursing pathway on postoperative satisfaction and quality of life of patients with subarachnoid hemorrhage.

Objective: To explore the effects of clinical nursing pathway (CNP) on the postoperative satisfaction and quality of life (QOL) of patients with subarachnoid hemorrhage (SAH). Methods: This is a retrospective study. Eighty patients with SAH admitted to Baoding No.1 Central Hospital from June 2021 to January 2023 were prospectively divided into a observation group and a control group by random numbers. The control group was given routine nursing, and the observation group was additional given CNP. The prognosis, cognitive function, QOL, self-care ability, nursing satisfaction and the incidence of complications were compared between the two groups. Results: After CNP nursing, the GCS and MMSE scores in the observation group were higher than those in the control group 14 days, one month and six months after the operation; and the difference was statistically significant (p< 0.05). Six months after the operation, the SS-QOL and Ability of daily living (ADL) scores in both groups were significantly improved compared with those before the intervention; and the improvement in the observation group was significantly better than that in the control group; and the difference was statistically significant(p<0.05). The nursing satisfaction score in the observation group was significantly higher than in the control group. The total incidence of complications in the observation group was lower than that in the control group. Conclusions: The CNP intervention in perioperative period of SAH patients has remarkable clinical effect, can improve the pertinence and efficiency of nursing, promote patients to recover as soon as possible, significantly improve the QOL of patients,and is worthy of clinical popularization.

Ultrasensitive and Specific Phage@DNAzyme Probe-Triggered Fluorescent Click Chemistry for On-Site Detection of Foodborne Pathogens Using a Smartphone.

Rapid, specific, and on-site detection of virulent foodborne pathogenic strains plays a key role in controlling food safety. In this work, an ultrasensitive and specific Phage@DNAzyme signal probe was designed to detect foodborne pathogens. The proposed sensing probe was composed of the selected phage and functionalized DNAzyme, which realized the specific recognition of target foodborne pathogens at the strain level and the efficient catalysis of copper(II) based azide-alkyne cycloaddition (CuAAC) click reaction with fluorescent signal, respectively. As a proof of concept, the virulent Escherichia coli O157:H7 (E. coli O157:H7) as the representative analyte was first enriched and purified from the complex food samples by a 4-mercaptophenylboronic acid-modified gold slide. Following, the Phage@DNAzyme probes were specifically combined with the captured E. coli O157: H7 and catalyzed the click reaction between 3-azido-7-hydroxycoumarin and 3-butyn-1-ol with the assistance of Cu(II) to generate a visual fluorescent signal. Finally, the corresponding fluorescent signals were measured by a smartphone to quantify the target concentrations. Under optimized conditions, the bioassay exhibited a wide linear range from 102 to 108 CFU/mL and the detection limit was 50 CFU/mL (S/N = 3). It was further extended to the detection of another foodborne pathogen Salmonella typhimurium with satisfying sensing performances. This work gives a new path for developing rapid, specific, and on-site detection methods for trace levels of pathogenic strains in foods.

Dual-Mode Gold Nanocluster-Based Nanoprobe Platform for Two-Photon Fluorescence Imaging and Fluorescence Lifetime Imaging of Intracellular Endogenous miRNA.

Bioimaging is widely used in various fields of modern medicine. Fluorescence imaging has the advantages of high sensitivity, high selectivity, noninvasiveness, in situ imaging, and so on. However, one-photon (OP) fluorescence imaging has problems, such as low tissue penetration depth and low spatiotemporal resolution. These disadvantages can be solved by two-photon (TP) fluorescence imaging. However, TP imaging still uses fluorescence intensity as a signal. The complexity of organisms will inevitably affect the change of fluorescence intensity, cause false-positive signals, and affect the accuracy of the results obtained. Fluorescence lifetime imaging (FLIM) is different from other kinds of fluorescence imaging, which is an intrinsic property of the material and independent of the material concentration and fluorescence intensity. FLIM can effectively avoid the fluctuation of TP imaging based on fluorescence intensity and the interference of autofluorescence. Therefore, based on silica-coated gold nanoclusters (AuNCs@SiO2) combined with nucleic acid probes, the dual-mode nanoprobe platform was constructed for TP and FLIM imaging of intracellular endogenous miRNA-21 for the first time. First, the dual-mode nanoprobe used a dual fluorescence quencher of BHQ2 and graphene oxide (GO), which has a high signal-to-noise ratio and anti-interference. Second, the dual-mode nanoprobe can detect miR-21 with high sensitivity and selectivity in vitro, with a detection limit of 0.91 nM. Finally, the dual-mode nanoprobes performed satisfactory TP fluorescence imaging (330.0 µm penetration depth) and FLIM (τave = 50.0 ns) of endogenous miR-21 in living cells and tissues. The dual-mode platforms have promising applications in miRNA-based early detection and therapy and hold much promise for improving clinical efficacy.

A microfluidic chip-based multivalent DNA walker amplification biosensor for the simultaneous detection of multiple food-borne pathogens.

The rapid, simultaneous, sensitive detection of the targets has important application prospects for disease diagnosis and biomedical studies. However, in practical applications, the content of the targets is usually very low, and signal amplification strategies are often needed to improve the detection sensitivity. DNAzyme-driven DNA walkers are an excellent signal amplification strategy due to their outstanding specificity and sensitivity. Food-borne pathogens have always been a foremost threat to human health, and it is an urgent demand to develop a simple, rapid, sensitive, and portable detection method for food-borne pathogens. In addition, there are various species of pathogens, and it is difficult to simultaneously detect multiple pathogens by a single DNA walker. For this reason, a substrate strand with three rA cleavage sites was cleverly designed, and a multivalent DNA walker sensor combined with the microfluidic chip technology was proposed for the simultaneous, rapid, sensitive analysis of Vibrio parahaemolyticus, Salmonella typhimurium, and Staphylococcus aureus. The developed sensor could be used to detect pathogens simultaneously and efficiently with low detection limits and wide detection ranges. Moreover, the combination of gold stirring rod enrichment and DNA walker achieved double amplification, which greatly improved the detection sensitivity. More importantly, by changing the design of the substrate chain, the sensor was expected to be used to detect other targets, thus broadening the scope of practical applications. Therefore, the sensor can build novel detection tool platforms in the field of biosensing.

Clinical evaluation of Alprostadil combined with Nimodipine in treatment of Cerebral Vasospasm after Subarachnoid Hemorrhage in elderly patients.

Objective: To analyze the clinical efficacy of alprostadil combined with nimodipine in the treatment of cerebral vasospasm (CVS) after subarachnoid hemorrhage (SAH) in elderly patients. Methods: This is a retrospective study. According to different treatment methods, the elderly 100 patients with CVS after SAH hospitalized in Baoding First Central Hospital from March 2020 to May 2021 were randomly divided into control group and observation group, with 50 patients in each group. The control group was treated with nimodipine, while the observation group was additionally combined with alprostadil. The levels of inflammatory factors and hemorheological indexes were measured before and after treatment. The clinical efficacy was compared and the adverse reactions were observed of the two groups. Results: The overall clinical efficacy in the observation group (95.00%) was significantly higher than that in the control group (74.00%) (p<0.05). After treatment, serum tumor necrosis factor-α (TNF-α), interleukin-8 (IL-8), high-sensitivity C-reactive protein (hs-CRP) and hemorheological indexes such as plasma viscosity, whole blood viscosity at high shear, whole blood viscosity at low shear, hematocrit and platelet adhesion decreased significantly compared with those before treatment (p<0.05), which were more obvious in the observation group (p<0.05). During treatment, the rate of adverse reactions in the observation group was 12.00%, and that in the control group was 8.00%, without statistically significant difference between the two groups (p> 0.05). Conclusion: Alprostadil combined with nimodipine is markedly effective in the treatment of CVS after SAH in elderly patients. It can effectively reduce inflammatory factor levels and improve hemorheological indexes in patients, which is conducive to the repair of neurological function.

Effect of nimodipine combined with atorvastatin calcium on microinflammation and oxidative stress levels in patients with cerebral vasospasm after subarachnoid hemorrhage.

Objective: To evaluate the effect of nimodipine combined with atorvastatin calcium on the micro inflammation and oxidative stress levels in patients with cerebral vasospasm (CVS) after subarachnoid hemorrhage (SAH) and its clinical implications. Methods: A total of 80 patients with CVS caused by SAH who had been admitted to Baoding First Central Hospital from August 2021 to August 2022 were selected and randomly divided into two groups. The control group underwent conventional symptomatic treatment, while the experimental group was administered nimodipine combined with atorvastatin calcium on the basis of conventional treatment. The changes in the micro inflammatory cytokines and oxidative stress factors in the two groups were compared, as well as the differences in clinical efficacy and incidence of adverse drug reactions. Result: After treatment, the levels of inflammatory cytokines in the experimental group decreased more significantly than those in the control group (p=0.00). After treatment, the serum levels of oxidative stress factors were obviously higher in the experimental group than in the control group (p=0.00). After treatment, the total efficacy was 77.5% in the experimental group and 55% in the control group, and the difference was statistically significant (p=0.04). Conclusions: Nimodipine combined with atorvastatin calcium could significantly improve the clinical symptoms in patients with CVS after SAH, which would be beneficial, safe, and effective for the patient's recovery.

Effects of Butylphthalide Combined with Fasudil on Inflammatory Factors, Cognitive Function and Vascular Endothelial Function in Patients with Subarachnoid Hemorrhage Complicated with Cerebral Vasospasm.

Objective: To investigate the effect of butylphthalide combined with fasudil in the treatment of subarachnoid hemorrhage (SAH) with cerebral vasospasm (CVS) on inflammatory factors, cognitive function and vascular endothelial function. Methods: It is a retrospective study in which a total of 104 patients with SAH with CVS admitted to Baoding First Central Hospital from July 2020 to February 2022 were selected and randomly divided into two groups by drawing lots. Patients in the control group were treated with basic symptomatic treatment, while those in the observation group were treated with butylphthalide soft capsule combined with fasudil hydrochloride injection on the basis of the control group. Before and after treatment, serum neuron specific enolase (NSE), tumor necrosis factor-α(TNF-α), interleukin-8(IL-8), hypersensitive C-reactive protein (CRP), Birmingham Cognitive Screen test (BCoS) score, serum soluble intercellular adhesion molecule-1(ICAM-1), serum endothelin-1(ET-1), vascular endothelial growth factor (VEGF) levels, and endothelium-dependent vasodilation function (FMD) in the two groups were compared. Results: After treatment, the expression levels of NSE, TNF-α, IL-8 and CRP in the two groups were significantly decreased, and the expression levels of all indicators in the observation group were lower than that in the control group (p<0.05). After treatment, the scores of orientations, attention, memory, language, practice and action in the two groups were significantly increased, and the scores of all dimensions in the observation group were higher than those in the control group (p<0.05). After treatment, S-ICAM-1, ET-1, VEGF, FMD decreased in both groups, and all indicators of the observation group were lower than those of the control group, with statistically significant differences (p<0.05). Conclusion: Butylphthalide combined with fasudil therapy was found as effective in reducing inflammatory factors, ameliorating cognitive function and vascular endothelial function in patients with subarachnoid hemorrhage complicated with cerebral vasospasm.

Surface Mineralization of the TiO2-SiO2/PES Composite Membrane with Outstanding Separation Property via Facile Vapor-Ventilated In Situ Chemical Deposition.

Conventional polymeric membranes are broadly employed in water treatment processes; however, most of them suffer from relatively low water permeance and severe membrane fouling phenomena owing to their relatively hydrophobic nature. In this work, a novel class of inorganic-organic composite membranes was developed through a newly developed vapor-ventilated in situ chemical deposition method, where the Ti and Si precursors were first hydrolyzed and then conferred into metal oxides to form a continuous TiO2-SiO2 modification layer. Owing to the distinct physicochemical properties, the Ti and Si precursors were leveraged as quasi-molecular regulators to tune the membrane surface chemistry and pore aperture (within the nanoscale) to benefit highly efficient water purification by underpinning the rapid transport of water molecules and featuring an excellent fouling-resistant and fouling-releasing property against typical pollutants. The as-developed TiO2-SiO2/PES composite membrane showed a high water permeance of 187.4 L·m-2·h-1·bar-1, together with a relatively small mean pore aperture of 4.2 nm, showing an outstanding permeating efficiency among state-of-the-art membranes with a similar separation accuracy. This study provides a paradigm shift in membrane materials that could open avenues for developing high-performance inorganic-organic composite membranes for complex wastewater treatment.

High-speed identification system for fresh tea leaves based on phenotypic characteristics utilizing an improved genetic algorithm.

BACKGROUND: High-quality tea requires leaves of similar size and tenderness. The grade of the fresh leaves determines the quality of the tea. The automated classification of fresh tea leaves improves resource utilization and reduces manual picking costs. The present study proposes a method based on an improved genetic algorithm for identifying fresh tea leaves in high-speed parabolic motion using the phenotypic characteristics of the leaves. During parabolic flight, light is transmitted through the tea leaves, and six types of fresh tea leaves can be quickly identified by a camera. RESULTS: The influence of combinations of morphology, color, and custom corner-point morphological features on the classification results were investigated, and the necessary dimensionality of the model was tested. After feature selection and combination, the classification performance of the Naive Bayes, k-nearest neighbor, and support vector machine algorithms were compared. The recognition time of Naive Bayes was the shortest, whereas the accuracy of support vector machine had the best classification accuracy at approximately 97%. The support vector machine algorithm with only three feature dimensions (equivalent diameter, circularity, and skeleton endpoints) can meet production requirements with an accuracy rate reaching 92.5%. The proposed algorithm was tested by using the Swedish leaf and Flavia data sets, on which it achieved accuracies of 99.57% and 99.44%, respectively, demonstrating the flexibility and efficiency of the recognition scheme detailed in the present study. CONCLUSION: This research provides an efficient tea leaves recognition system that can be applied to production lines to reduce manual picking costs. © 2022 Society of Chemical Industry.

Analysis on efficacy of compound dextran combined with atorvastatin calcium in patients with CVS caused by SAH based on TCD blood flow indexes.

Objectives: To analyze the effects of compound dextran combined with atorvastatin calcium on blood flow indexes, peroxidase 2 (Prx2) and endothelin-1 (ET-1) in patients with cerebral vasospasm (CVS) caused by subarachnoid hemorrhage (SAH). Methods: One hundred patients with CVS caused by SAH treated in Baoding No.1 Central Hospital from January 2019 to December 2020 were divided into observation group and control group. The control group was treated with atorvastatin calcium tablets, while the observation group was additionally treated with compound dextran. The hospital stays, Glasgow Outcome Scale (GOS), hemoglobin (Hb) and hematocrit (Hct) levels before and five days after treatment were recorded. The hemodynamic parameters of the middle cerebral artery (MCA) and the serum levels of Prx2 and ET-1 were detected. Results: After treatment, GOS and Hct levels in the observation group were both higher than those in the control group (P < 0.05). After treatment, the mean and peak velocities of the MCA in the observation group were significantly lower than those in the control group (P < 0.05). After treatment, the serum levels of Prx2 and ET-1 in the observation group were significantly lower compared with those in the control group (P < 0.05). However, no significant differences were found in the incidences of adverse reactions between the two groups (P > 0.05). Conclusions: Compound dextran combined with atorvastatin calcium can effectively enhance clinical efficacy, improve cerebral blood flow and reduce serum Prx2 and ET-1 levels in patients with CVS caused by SAH.

Two-Photon CQDs-Based Dual-Mode Nanoprobe for Fluorescence Imaging and Magnetic Resonance Imaging of Intracellular Wide pH.

Biological fluorescence imaging technologies have attracted a lot of attention and have been widely used in biomedical fields. Compared with other technologies, fluorescence imaging has a lower cost, higher sensitivity, and easier operation. However, due to the disadvantages of one-photon (OP) fluorescence imaging, such as low spatial and poor temporal resolution and poor tissue permeability depth, the application of OP fluorescence imaging has some limitations. Though two-photon (TP) fluorescence imaging can well overcome these shortcomings of OP, the single-mode imaging remains deficient. Therefore, dual-mode imaging combined with TP imaging and magnetic resonance imaging (MRI) can make up for the deficiency well, which make dual-mode imaging for the early diagnosis of diseases more accurate. Hence, a dual-mode nanoprobe TP-CQDs@MnO2 was designed for probing the fluorescence/MR dual-mode imaging strategy of intracellular H+ by using TP-CQDs (two photon-carbon quantum dots) and MnO2 nanosheets. The MnO2 nanosheets treated as fluorescence quenching agents of TP-CQDs exhibited a supersensitive response to H+, which made the fluorescence signals turn "off" to "on" for TP fluorescence imaging, in the meantime, large amounts of Mn2+ were generated for MRI. A dual-mode nanoprobe TP-CQDs@MnO2 can monitor intracellular wide pH (4.0-8.0), and the fluorescence intensity of TP-CQDs@MnO2 has recovered up to more than six times and the corresponding results of MRI were satisfactory. TP fluorescence imaging of cells and tissues showed higher detection sensitivity and deeper tissue penetration (240.0 µm) than OP. The dual-mode imaging platform hold great promise for pH-related early diagnosis and treatment, which has great potential to improve clinical efficacy.

Progranulin Decreases Susceptibility to Streptococcus pneumoniae in Influenza and Protects against Lethal Coinfection.

Streptococcus pneumoniae coinfection is a major cause of mortality in influenza pandemics. Growing evidence shows that uncontrolled immune response results in severe tissue damage and thereby promotes death in coinfection. Progranulin (PGRN) is widely expressed in immune and epithelial cells and exerts anti-inflammatory role in many diseases. We found that PGRN levels were significantly elevated in clinical influenza/S. pneumoniae-coinfected patients. C57BL/6 wild-type (WT) and PGRN-deficient (PGRN-/-) mice were infected with influenza virus PR8 and then superchallenged with S. pneumoniae serotype 19F. Coinfected PGRN-/- mice showed increased mortality and weight loss compared with WT mice. PGRN deficiency led to increased bacterial loads in lungs without altering influenza virus replication, suggesting a role of PGRN in decreasing postinfluenza susceptibility to S. pneumoniae coinfection. Administration of recombinant PGRN improved survival of WT and PGRN-/- mice in lethal coinfection. Additionally, loss of PGRN resulted in aggravated lung damage along with massive proinflammatory cytokine production and immune cell infiltration during coinfection. Endoplasmic reticulum stress (ERS) during influenza, and coinfection was strongly induced in PGRN-/- mice that subsequently activated apoptosis signaling pathways. Treatment of recombinant PGRN or inhibition of ERS by 4-phenylbutyrate decreased apoptosis and bacterial loads in lungs of coinfected mice. These results suggest that PGRN decreases postinfluenza susceptibility to S. pneumoniae coinfection via suppressing ERS-mediated apoptosis. Impaired bacterial clearance and increased lung inflammation are associated with the lethal outcome of coinfected PGRN-/- mice. Our study provides therapeutic implication of PGRN to reduce morbidity and mortality in influenza/S. pneumoniae coinfection.

Dual-mode aptasensor for simultaneous detection of multiple food-borne pathogenic bacteria based on colorimetry and microfluidic chip using stir bar sorptive extraction.

A dual-mode aptasensor using colorimetry and microfluidic chip (MC) together with stir bar sorptive extraction (SBSE) has been developed for firstly qualifying samples contaminated with Vibrio parahaemolyticus (V.P) and Salmonella typhimurium (S.T), then precisely determine both of them in positive samples. For this purpose, the aptamer-streptavidin encoded probes (Apt-SAEs) corresponding to different bacteria were prepared in advance. Then, a stir bar modified with 4-mercaptophenylboronic acid (MPBA) was made to extract bacteria together with Apt-SAE probes. The binding event of aptamer and target triggered the formation of two sandwich structures containing Apt-SAE, V.P or S.T. The concentration of bacteria could be enriched by 1000 times within 15 min to avoid long-time enrichment process. Finally, the stir bar was immersed in the 3,3',5,5'-Tetramethylbenzidine (TMB)-H2O2 solution for color development. The color could be observed by naked eyes to judge whether the analytes were present. The colorless samples were judged to be negative. For the positive samples, the adsorbed encoded probes corresponding to different bacteria would be eluted from the stir bar and rapidly analyzed by the MC. Under the optimized conditions, 100 CFU/mL of V.P or S.T or both of them could be observed by colorimetry and 35 CFU/mL of them could be detected (S/N = 3) by the MC. The assay has significant application value for on-site screening and multiple detection of food-borne pathogenic bacteria.

A turn-on-type fluorescence resonance energy transfer aptasensor for vibrio detection using aptamer-modified polyhedral oligomeric silsesquioxane-perovskite quantum dots/Ti3C2 MXenes composite probes.

A pair of composite probes based on aptamer modified polyhedral oligomeric silsesquioxane-perovskite quantum dots (POSS-PQDs-Apt) as signal probe and titanium carbide (Ti3C2) MXenes as quencher were prepared for the first time. They were employed to fabricate one turn-on-type aptasensor relying on fluorescence resonance energy transfer (FRET) for Vibrio parahaemolyticus (VP) determination. The POSS-PQDs-Apt can be adsorbed on the MXenes nanosheets, and its fluorescence was quenched due to the FRET. After the composite probes were incubated with VP for 50 min, the POSS-PQDs-Apt binding with VP can be released from the surface of MXenes, and the signal recovered due to its higher affinity to the VP than MXenes. The fluorescence intensity from 519 nm emission of the system was measured at 480 nm excitation. Under In optimized conditions, the assay can determine VP in the concentration range 102 - 106 cfu/mL, and the detection limit (LOD) was 30 cfu/mL using fluorescence detection. The LOD is still 100 cfu/mL by naked eye detection which is proper for on-line monitoring VP in aquaculture water. This method was also used to detect VP in actual samples of seawater, the recovery of spiked samples was between 93% and 106%, and relative standard deviation (RSD) was between 2.7% and 6.7%. The result is consistent with the plate count. Therefore, this assay could provide a candidate platform for screening VP in aquaculture industry.

Ursodeoxycholic acid protects against lung injury induced by fat embolism syndrome.

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a life-threatening disease with a high mortality rate, which was a common complication of fat embolism syndrome (FES). Ursodeoxycholic acid (UDCA) has been reported to exert potent anti-inflammatory effects under various conditions. In vivo, perinephric fat was injected via tail vein to establish a rat FES model, the anti-inflammatory effects of UDCA on FES-induced lung injury were investigated through histological examination, ELISA, qRT-PCR, Western blot and immunofluorescence. In vitro, human lung microvascular endothelial cells (HPMECs) were employed to understand the protective effects of UDCA. The extent of ALI/ARDS was evaluated and validated by reduced PaO2 /FiO2 ratios, increased lung wet/dry (W/D) ratios and impaired alveolar-capillary barrier, up-regulation of ALI-related proteins in lung tissues (including myeloperoxidase [MPO], vascular cell adhesion molecule 1 [VCAM-1], intercellular cell adhesion molecule-1 [ICAM-1]), elevated protein concentration and increased proinflammatory cytokines levels (TNF-α and IL-1ß) in bronchoalveolar lavage fluid (BALF). Pre-treatment with UDCA remarkably alleviated these pathologic and biochemical changes of FES-induced ALI/ARDS; our data demonstrated that pre-treatment with UDCA attenuated the pathologic and biochemical changes of FES-induced ARDS, which provided a possible preventive therapy for lung injury caused by FES.

Optimized Ge-As-Se-Te chalcogenide glass fiber sensor with polydopamine-coated tapered zone for the highly sensitive detection of p-xylene in waters.

A novel Ge-As-Se-Te chalcogenide glass (ChG)-tapered fiber (ChG-TF) sensor for detecting environmentally relevant organic pollutants with p-xylene as the model was investigated. The prominent design feature of the sensor is that its tapered zone was coated with a polydopamine membrane by a facile in situ self-polymerization process. As the tapered zone exposed to the aqueous sample, the p-xylene molecules would be enriched into the polydopamine coating. The detection limit for p-xylene aqueous solution obtained by the polydopamine-coated sensor was decreased to 50 µg/mL, which was approximately 2.5% that of the uncoated one. To the best of our knowledge, this paper is the first report of a polymer membrane coating, which can significantly enhance the sensitivity of the ChG-TF sensor. The straightforward test features and the capacity of the sensor to detect organic pollutants with as low as ppm range revealed that this sensor has great potential for online, in situ environmental qualification.