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OBJECTIVE: Carbapenem-resistant P. aeruginosa (CRPA) is particularly worrisome because of its resistance against multiple antimicrobial agents which reduces treatment options. The efflux pump decreases antibiotic abundance, and biofilm impairs the penetration of antibiotics. The aim of the present study was to evaluate the role and relationship of efflux pump and biofilm formation in CRPA isolates obtained from different clinical samples PATIENTS AND METHODS: A total of 110 different clinical samples were collected from three tertiary medical hospitals. The samples were subjected to isolation and identification by standard operating procedures. Species level were identified using Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry system. Antibiotic susceptibility testing was done by broth microdilution method. Crystal violet (CV) staining for observing the biofilm forming ability and amplification of efflux pump mexA gene were also performed on clinical CRPA isolates. Three efflux pump MexAB-OprM regulatory genes were analyzed using sequencing methods. The expression of mexA gene both in biofilm and planktonic bacteria was observed by Quantitative real-time PCR (qRT-PCR). RESULTS: The results showed that 110 samples were CRPA and among them 83 (75.5%) were MDR isolates. The CV staining showed 105 (95.5%) isolates as biofilm producers while 78 (74.3%) MDR isolates showed biofilm formation. mexA hyperexpression was detected in 27 (24.5%) CRPA isolates while 26 (96.3%) in biofilm forming isolates and 96.3% (26/27) in MDR P. aeruginosa. Multiple mutations in nalC, nalD, and mexR genes were detected. The distinct difference confirmed that the expression of mexA gene in P. aeruginosa biofilm producer was significantly higher than that of planktonic bacteria in vitro, and the efflux pump inhibitor PAßN significantly inhibited biofilms in CRPA isolated from clinical samples. CONCLUSIONS: The biofilm and efflux pumps might be two intertwined processes involved in CRPA isolates. Their synergistic effect magnified the drug resistance characteristics of P. aeruginosa. [ABSTRACT FROM AUTHOR]

OBJECTIVE: PPP2R3A plays a key role in the cardiac pathological and physiological processes, yet little is known about how the protein involved in normal myocardium formation and the protein-protein interaction pathways involved. To address this issue, we investigated the role of PPP2R3A in cardiac myocytes and identify PPP2R3A specific protein interaction partners to accelerate the developmental process of the mechanistic studies. MATERIALS AND METHODS: PPP2R3A-silenced primary myocardial cell of neonatal rats and H9c2 cells were established by infecting shRNA lentiviral particles. RT-PCR and Western blot were used to determine the expression of PPP2R3A and silencing efficiency. The cell viability was analyzed by CCK-8 kit, then the cell cycles and apoptosis assays were detected by flow cytometry. Novel protein-protein interactions of PPP2R3A were detected by Yeast Two-Hybrid assays using a high-quality human primary cardiomyocyte cDNA library. RESULTS: PPP2R3A-silencing rat primary cardiomyocytes and H9c2 cells were established successfully, and the expression of PPP2R3A was downregulated significantly as confirmed by RTPCR and Western blot. PPP2R3A silencing can inhibit the myocardial cell proliferation, arrest the cell cycle in the S phase and promote the cardiomyocytes apoptosis. 19 potential candidates like COL1A2, GIPC1and BCL6 specifically interact with PPP2R3A, and COL1A2 was the highest screening frequency, covering 12.5% of the 24 clones. These partners are highly enriched in signaling pathways associated with a variety of cellular processes. CONCLUSIONS: A series of studies have discovered that PPP2R3A was closely associated with heart failure and arrhythmia. Our data further confirmed PPP2R3A plays an important role in the cardiomyocytes and PPP2R3A in the regulation of cardiac events via its interaction partners. Therefore, it is a potential therapeutic target for the disease. [ABSTRACT FROM AUTHOR]

The crystal structure and superconducting properties of RuSr[sub 2-x]Ba[sub x]GdCu[sub 2]O[sub 8] (0<=x<=0.1) have been investigated. X-ray powder diffraction (XRD) patterns show that the solid solution range is 0<=x<=0.1. The superconducting transition temperature was raised up to 35 K (zero) and 62 K (onset) for x=0.07, from 16 K (zero) and 45 K (onset) for x=0.0, and then T[sub C] decreases with x when x>0.07. Rietveld refinement for XRD data of RuSr[sub 2-x]Ba[sub x]GdCu[sub 2]O[sub 8] show that the apical Cu–O(1) bond length increases with an increase of x, while the Ru–O(1) bond length decreases, This may account for the enhancement of the superconducting transition temperature. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

What is known and objective Warfarin is a widely used anticoagulant with a narrow therapeutic index. Polymorphisms in the VKORC1, CYP2C9 and CYP4F2 genes have been verified to correlate with warfarin stable dosage ( WSD). Whether any other genes or variants affect the dosage is unknown. The aim of our study was to investigate the relationship between GGCX, miR-133 variants and the WSD in Han Chinese patients with mechanical heart valve replacement ( MHVR). Methods A total of 231 patients were enrolled in the study. Blood samples were collected for genotyping. The average WSD among subjects with different GGCX or miR-133 genotypes was compared. Regression analyses were performed to test for any association of genetic polymorphisms with WSD. Results and discussion The warfarin dosage in patients with the GGCX rs699664 TT and rs12714145 TT genotypes was 3.77±0.93 (95% CI: 3.35-4.19) mg/d and 3.70±1.00 (95% CI: 3.32-4.09) mg/d, respectively. The GGCX rs699664 and rs12714145 genotypes were significantly associated with WSD ( P<.05). But they were ruled out in the multivariate regression analysis. There were no significant differences in the average warfarin stable dosage between subjects with MIR133B rs142410335 wild-type and variant genotypes ( P>.05). What is new and conclusion The genotypes of GGCX rs699644 and rs12714145 were significantly associated with WSD ( P<.05), but their contributions were not significant after accounting for other factors. MIR133B rs142410335 makes no significant contributions to warfarin stable dosage in Han Chinese patients with MHVR neither in univariate regression nor in multivariate regression analyses. [ABSTRACT FROM AUTHOR]

Although agricultural robots are intended to move in straight lines in fields, they may yaw off the track because of tire slippage, surface unevenness, uneven weight distribution, or other factors. Many position-guiding technologies have been developed for agricultural robots, but their high costs have resulted in limited real-world use. Moreover, the use of large farming machinery in conjunction with the enormous tractors that are used to perform farm work can result in the destruction of cultivated land. This article presents the design and implementation of a low-cost planting robot with the capability of high-precision straight-line navigation. A two-stage guidance control scheme is proposed to regulate the robot's heading angle and minimize the lateral error in straight-line navigation. A low-cost micro-electro-mechanical control system is used to implement the proposed scheme. The control method requires only a single-axis electronic compass, with a stabilizing algorithm to keep the compass level, to serve as a guide. The proposed robot is equipped with a mini-drilling mechanism to perform cultivation work. The proposed scheme has been experimentally tested in a greenhouse. A performance analysis of the proposed robot is discussed. [ABSTRACT FROM AUTHOR]

The compound FeSr2NdCu2O7+d (Fe1212) was successfully synthesized by solid-state reaction. X-ray diffraction data indicate that the sample is of single phase. Rietveld whole-pattern-fitting method was used to refine the crystal structure of samples prepared under different annealing conditions using the tetragonal system with space group P4/mmm. Magnetization measurements indicate that magnetic susceptibility ? changes with temperature in a Curie-type manner. Resistance measurements indicate that these samples have a semiconductor-like behavior. [ABSTRACT FROM AUTHOR]

The Pr[1 +x -y]Ba[2 -x -z]Ca[y +z]Cu[3]O[7] ±... solid solution was investigated by means of X-ray powder diffraction combined with Rietveld analysis. A Pr123 single phase could be synthesized under Pr-rich conditions by sintering at 950 °C in air. The solubility range of Pr[1 +x -y]Ba[2 -x -z]Ca[y +z]Cu[3]O[7] ± solid solution is 0.08 ≤x≤0.80. The structure of Pr[1 +x -y]Ba[2 -x -z]Ca[y +z]Cu[3]O[7] ± for 0.08≤x≤0.30 is orthorhombic. The structure transforms into tetragonal for 0.30≤x≤0.80. To form the Pr123 single phase, the Ba sites in the Pr123 structure must have partial Pr ions, and the least amount is x = 0.08. Ba ions cannot occupy the sites of Pr ions, In the Pr123 structure, Ca ions can replace Pr ions; the highest value is x = 0.4 in the PrBa2 -xCaxCu3O7±s system under our experimental conditions, However, Ca ions cannot replace Ba ions, The ionic radius plays a more important role than the chemical properties in the substitution between Pr, Ba and Ca ions in the Pr123 structure. [ABSTRACT FROM AUTHOR]

The compound FeSr2NdCu2O7+d (Fe1212) was successfully synthesized by solid-state reaction. X-ray diffraction data indicate that the sample is of single phase. Rietveld whole-pattern-fitting method was used to refine the crystal structure of samples prepared under different annealing conditions using the tetragonal system with space group P4/mmm. Magnetization measurements indicate that magnetic susceptibility ? changes with temperature in a Curie-type manner. Resistance measurements indicate that these samples have a semiconductor-like behavior. [ABSTRACT FROM AUTHOR]