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Dispersin B (DspB) is a member of glycoside hydrolase family 20 (GH20) and catalyzes degradation of biofilms forming by pathogenic bacteria such as Staphylococcus aureus. Magnetoreceptor (MagR) is a magnetic protein that can be used as a fusion partner for functionally immobilizing proteins on magnetic surfaces. In the present study, a recombinant protein DspB-MagR was constructed by fusing MagR to the C-terminus of DspB and expressed in Escherichia coli. Magnetic immobilization of purified DspB-MagR on magnetic core–shell structured Fe3O4@SiO2 nanoparticles was achieved and characterized by means of various techniques including SDS-PAGE, Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential measurement, and scanning electron microscopy. It was evaluated the influence of temperature, pH, and storage time on the performance of immobilized DspB-MagR on Fe3O4@SiO2 nanoparticles. Removal of biofilms forming by Staphylococcus aureus and other medical sourced bacterial species was achieved by using Fe3O4@SiO2 nanoparticles loading with DspB-MagR. This work promoted potential applications of DspB and similar enzymes for medical purposes.

For adults with small radial arteries, ultrasound-guided radial artery cannulation remains challenging and the relevant data is currently lacking. The study aimed to test the hypothesis that modified long-axis in-plane ultrasound guidance (M-LAIP) would improve success rates of radial artery cannulation in this population.This was a prospective, randomised, and controlled clinical study that enrolled 201 adult patients with diameters of the radial artery less than 2.2 mm. Patients were randomised to M-LAIP, short-axis out-of-plane (SAOP), or conventional palpation (C-P) group according to different approaches of radial artery cannulation (M-LAIP, SAOP, and C-P). Outcome measurements included the success rate, cannulation time, and cannulation-related adverse events.The cannulation success rate was significantly higher in the M-LAIP group than in the SAOP or C-P groups (first success rate: 80.3% vs. 53.8% or 33.8%; P 0.001; total success rate: 93.9% vs. 78.5% or 50.8%; P 0.001). Total cannulation time in the M-LAIP group was shorter than that in the SAOP group (P = 0.002) or the C-P group (P 0.001). The rates of posterior wall puncture and haematoma in the M-LAIP group were lower than that in the SAOP group or C-P group (P 0.008).The use of the M-LAIP approach significantly improved the success rate of radial artery cannulation, shortened procedure time, and lowered the rates of posterior wall puncture and haematoma in adults with radial artery diameters less than 2.2 mm, compared with that achieved by the SAOP or C-P approach.

Dispersin B (DspB) is a member of glycoside hydrolase family 20 (GH20) and catalyzes degradation of biofilms forming by pathogenic bacteria such as Staphylococcus aureus. Magnetoreceptor (MagR) is a magnetic protein that can be used as a fusion partner for functionally immobilizing proteins on magnetic surfaces. In the present study, a recombinant protein DspB-MagR was constructed by fusing MagR to the C-terminus of DspB and expressed in Escherichia coli. Magnetic immobilization of purified DspB-MagR on Fe3O4@SiO2 nanoparticles was achieved and characterized by means of various techniques including SDS-PAGE, FTIR spectrometry, TGA measurements, zeta potential measurement, and SEM analysis. Stability and activity of immobilized DspB-MagR on Fe3O4@SiO2 nanoparticles were analyzed under different conditions such as temperature, pH, and storage time. Removal of biofilms forming by Staphylococcus aureus and other medical source bacterial species were achieved by using Fe3O4@SiO2 nanoparticles loading with DspB-MagR. This work promoted potential applications of DspB and similar enzymes for medical purposes.

Background: Given the low first-pass success rate of the conventional short-axis (SAX) or long-axis (LAX) approach, ultrasound-guided radial artery cannulation in adults with radial artery diameters less than 2.2 mm may still be challenging. In this study, we compare the efficacy of modified long-axis in-plane(M-LAIP) versus short-axis out-of-plane (SAOP) or conventional palpation(C-P) approaches for ultrasound-guided radial artery cannulation.Methods: This was a prospective, randomized and controlled trial, conducted from 1 July 2018 to 24 November 2018. A total of 201 patients (age 18 to 85 years, the diameter of the radial artery less 2.2 mm) were included. All patients were randomized 1:1:1 to the M-LAIP, SAOP or conventional palpation (C-P) approach. The primary outcome was the cannulation success rate. Secondary outcomes included first location time and cannulation time, number of attempts. The Chi-square (χ2) test was used to compare categorical data between 3 groups.Results: The cannulation success rate was significantly higher in the M-LAIP group than in the SAOP or C-P groups (first success rate: 80.3% vs 53.8% or 33.8%; p < 0.001; total success rate: 93.9% vs 78.5% or 50.8%; p < 0.001). First location time (seconds) was significantly longer in the M-LAIP group (31(28-35[12-44])) than in the SAOP (15(14-17[10-21]); p < 0.001) and C-P groups (12(8-13.5 [6-37]). However, the cannulation time (seconds) in the M-LAIP group (29(24-45[16-313])) was significantly shorter than that in the SAOP (45(28.5-135.5[14-346]); p = 0.002) and the C-P groups (138(27-308[12-363]); p < 0.001). The number of attempts was lower in the M-LAIP group compared with SAOP or C-P group (1.29±0.63 vs 1.8±0.89 or 2.22±0.93, p < 0.001).Conclusions: The use of the M-LAIP approaches significantly improved the success rate of radial artery cannulation in adults with radial artery diameters less than 2.2 mm, compared with that achieved with the use of traditional short-axis out-of-plane approach.Trial registration: ClinicalTrials.gov; No: ChiCTR-IOR-17011474; URL: http: // www. chictr.org. cn/index.aspx. Registered 24 June 2018.

Widespread Mesozoic granitic plutons in the North China Craton (NCC) are products of remelting of the crust associated with large-scale Mesozoic destruction of the NCC. Mafic microgranular enclaves (MMEs) are common in these plutons and are attributed to magma mixing. However, the involved magmatic processes of the mixing are poorly known. In this paper, we reported complex zoning patterns, in situ U–Pb ages, and elemental and Nd isotopic compositions of titanite grains in the MMEs and host monzogranite of the Sanguliu pluton in the NCC. Titanite grains in the MMEs and monzogranite have similar U–Pb ages of ca.130 Ma, and display different internal textures and compositions. They can thus be divided into four types, i.e., types 1 and 2 from the host monzogranite, and types 3 and 4 from the MMEs. Type 1 is euhedral in shape, whereas type 2 has a euhedral inner domain and a thin deuteric rim with a sharp contact between them. Types 3 and 4 are angular grains. Type 3 shows a typical core-mantle-rim texture with a resorbed core, a mantle and an irregular rim, whereas type 4 contains a homogeneous inner domain and a discontinuous rim. Most titanite grains of the four types display oscillatory, fir-tree and sector zoning and have crystallization temperatures ranging from 680 to 750 °C based on the Zr-in-titanite thermometry, indicating a magmatic origin. The core of type 3 titanite has the highest eNd(t) of −11.3 to −12.5 among others, close to that of the mafic dykes (eNd(t) = −7.8 to −11.6) that intrude the Sanguliu pluton. The core can be interpreted as crystallized from the mixed magmas with more mafic components that were derived from metasomatized subcontinental lithospheric mantle (SCLM) beneath the NCC. The mantle of type 3 and the inner domain of type 4 titanite have eNd(t) (−13.0 to −15.3) nearly identical to that of the MMEs (−14.3 to −15.4), but distinctly higher than that of types 1 and 2 titanite (−15.9 to −18.3). The rims of types 3 and 4 titanite have eNd(t) (−16.1 to −18.3), identical to that of type 1 and the inner domain of type 2 titanite, however, they have REE concentrations and Th/U and Nb/Ta similar to the rim of type 2 titanite, clearly indicative of crystallization from evolved, hydrated, granitic magmas. A three-stage growth model is thus proposed to explain the core-mantle-rim texture of the titanite in the MMEs by a magma mixing process. The core likely crystallized from the mixed magma with more mafic components. It was then partially or totally resorbed by mixed, dioritic magma due to chemical disequilibrium, which was followed by the re-precipitation from the dioritic magma, forming the mantle. The rim is an overgrowth from the evolved, hydrated, granitic magma. This study demonstrates that the complex zoning patterns and compositions of titanite in the MMEs can be used to investigate magmatic processes including magma mixing.

To balance the relationship between weldability and properties, a series of Ni-based superalloys with varying amount of Cr-like elements were designed using a “cluster-plus-glue-atom” model, and fabricated by laser additive manufacturing (LAM). The microstructure of the as-deposited superalloys consists of few topological close packet (TCP) phases distributed between γ-Ni dendrites with epitaxial growth characteristic. With the increase of Cr-like elements amount, TCP phases change from granular Laves phase to long-striped Laves phase plus acicular σ phase, and exhibit a trend of first decreasing and then increasing in amount. The mechanism for such microstructure evolution was analyzed. Performance tests reveal that the NiCrlike-2 alloy (Ni54.8Fe20.3Cr17.3Mo1.50Al1.56 Nb3.47Ti1.22 at.%), which has the fewest amount of TCP phases, presents a novel combination of strength, ductility, high temperature oxidation-resistance, and good weldability.

BackgroundA low first-pass success rate of radial artery cannulation was obtained when using the conventional palpation technique(C-PT) or ultrasound-guided techniques, we therefore evaluate the effect of a modified long-axis in-plane ultrasound technique (M-LAINUT) in guiding radial artery cannulation in adults.MethodsWe conducted a prospective, randomized and controlled clinical trial of 288 patients undergoing radial artery cannulation. Patients were randomized 1:1 to M-LAINUT or C-PT group at fujian medical university union hospital between 2017 and 2018. Radial artery cannulation was performed by three anesthesiologists with different experience. The outcome was the first and total radial artery cannulation success rates, the number of attempts and the cannulation time.Results285 patients were statistically analyzed. The success rate of first attempt was 91.6% in the M-LAINUT group (n=143) and 57.7% in the C-PT group (n=142; PConclusionModified long-axis in-plane ultrasound-guided radial artery cannulation can increase the first and total radial artery cannulation success rates, reduce the number of attempts and shorten the total cannulation time in adults.