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OBJECTIVE: The aim of the present study was to investigate the mechanism of homocysteine (Hcy) induced oxidative stress in the human umbilical vein endothelial cells (HUVECs). PATIENTS AND METHODS: The HUVECs were isolated from umbilical vein vascular wall of 12 patients and treated with Hcy. The malondialdehyde (MDA) level was measured using the thiobarbituric acid (TBA) method. The expressions of superoxide dismutase 2 (SOD2), endothelial nitric oxide synthase (eNOS), and intercellular adhesion molecule 1 (ICAM-1) were detected by Western blot and RT-PCR. The genome-wide DNA methylation assay was performed using the Infinium Human Methylation 450 BeadChip. The specific DNA methylation was determined using bisulfite sequencing analysis. To evaluate the role of sorbin and SH3 domain-containing protein 1 (SORBS1), the HUVECs were transfected with small interfere RNA (siRNA) targeting SORBS1 (SORBS1-siRNA). RESULTS: Hcy induced MDA level in HUVECs, and increased ICAM-1 expression both in protein and mRNA levels. The protein and mRNA levels of SOD2 and eNOS were inhibited by Hcy induction. However, the effects of Hcy on MDA level and expressions of SOD2, eNOS, and ICAM-1 were attenuated by folic acid (Fc) and vitamin B12 (B12) treatment. DNA total methylation level in Hcy treated cells was significantly decreased compared to the control group, while the DNA total methylation levels were increased after treatment with Fc and B12. The methylation level of SORBS1 in Hcy treatment group was higher than that of control group. And the methylation level of SORBS1 induced by Hcy was attenuated by Fc and B12 treatment. SORBS1-siRNA transfection induced the MDA levels and reduced the expressions of SOD2 in HUVECs. CONCLUSIONS: We indicated that Hcy induced oxidative stress in HUVECs via regulating methylation of SORBS1. We also found that Fc and B12 treatment attenuated the oxidative stress and inflammation induced by Hcy in HUVECs. The findings indicated that Fc and B12 might be effective agents for the treatment of Hcy induced AS. [ABSTRACT FROM AUTHOR]

This study presents a novel time-reversal approach to locate targets based on the spatial information from the space-frequency multistatic data matrix plus the maximum detection and signal subtraction. The cancellation operator enables us to cancel the echoes coming from preliminarily detected targets, and we can transfer the multitarget imaging program into a series of single-target ones. Therefore, the targets can be accurately focused in the new environment. The advantages of the new algorithm over the conventional multitarget imaging algorithm are demonstrated by several numerical simulations. [ABSTRACT FROM AUTHOR]

An ultra-wideband (UWB) power divider is designed in this paper. The UWB performance of this power divider is obtained by using a tapered microstrip line that consists of exponential and elliptic sections. The coarse grained parallel micro-genetic algorithm (PMGA) and CST Microwave Studio are combined to achieve an automated parallel design process. The method is applied to optimize the UWB power divider. The optimized power divider is fabricated and measured. The measured results show relatively low insertion loss, good return loss, and high isolation between the output ports across the whole UWB (3.1-10.6 GHz). [ABSTRACT FROM AUTHOR]

Effcient global optimization has been extensively used in problems with expensive cost functions. However, this method is not suitable for high-dimensional problems. In this paper, the radial basis function network is introduced into the effcient global optimization, to avoid local optima and achieve a fast convergence for high-dimensional optimization. Our algorithm is applied to a 12-dimensional optimization of a transmitting antenna. Compared to the genetic-algorithm-based effcient global optimization and the differential evolution strategy, our algorithm converges to the global optimal value more effciently. [ABSTRACT FROM AUTHOR]

An evolutionary learning algorithm based on differential evolution strategy (DES) and continuous ant colony optimization (CACO) for wideband antenna design is proposed. The advantages of this hybrid method are demonstrated with several mathematical functions and a linear array pattern synthesis. This method is applied to design an E-shaped wideband patch antenna, which achieves the impedance bandwidth 4.8 ~ 6.53GHz. We compare the hybrid method with the traditional DES and CACO optimization algorithms, and the advantage of this hybrid method over the DES and the CACO is also demonstrated. [ABSTRACT FROM AUTHOR]

The paper presents an approach to locate and concentrate electromagnetic energy on targets based on time delays. An array of antennas is used in the approach, in which one antenna sends ultrawide-band signals, and all antennas receive the signals back scattered by the targets. The time delays can be obtained by the interrelation of the transmitted and received signals. By controlling the timing of the pulses radiated from the individual antennas, high concentration of electromagnetic energy on the targets' locations can be achieved. The performance of this approach is demonstrated by several numerical simulations. [ABSTRACT FROM AUTHOR]

Objective: To analyze the genotype-phenotype correlations among those thalassemia samples with the presence of -α(3.7,) --(SEA) and normal α(2) alleles on their α-globin gene clusters. Methods: Fourteen patients(including 1fetus, 4 males and 9 females, aged 0- 56 years old)who were suspected diagnosed by hematologic analysis and genetic testing among 16 080 participants in our laboratory since from August 2011 to August 2016, were enrolled. Complete blood cell count was performed on XE4000i automatic hemocyte analyzer. HbA0, HbF and HbA2 were tested by high performance liquid chromatography (HPLC). Gap-PCR was adopted to detect three common deletional thalassemia deletions. Reverse dot-blot (RDB) assay was applied for detecting 17 common β-globin gene mutations and three common non-deletional α(2) gene mutations. Two-round nested PCR assay was established to detect the genotype of HKαα in α-thalassemia. Results: Fourteen cases were identified as HKαα/--(SEA) (14/16 080), including a pedigree and a rare case of HKαα/--(SEA) co-inheritance with IVS-Ⅱ-654(C→T) heterozygote. In HKαα/--(SEA) thalassemia group, mean cell volume(MCV) was (69.54±5.92)fl, and mean cell hemoglobin(MCH) was(22.11±2.22)pg and hemoglobin(Hb) was (117.64±18.14) g/L. Compared with normal group, MCV, MCH and Hb in HKαα/--(SEA) thalassemia group, was significantly decreased( P <0.05). There were no significant differences between α-thalassemia control group(--(SEA) /αα) in most hematological parameters ( P >0.05). Conclusion: The two-round nested PCR could effectively detect the HKαα/--(SEA) genotype. The hematologic characteristics changed significantly in HKαα/--(SEA) group compared with HbH thalassemia and normal group. The genotype and phenotype non-correlation in patients with α-thalassemia should especially be causious to avoid a misdiagnosis of genetic tests, especially in prenatal diagnosis.

We demonstrate that the thickness and the dielectric constants of thin gold films deposited on the surface of a fiber core can be quantitatively determined as a single set of solutions by the simple measurement of the fiber-optic surface-plasmon resonance responses. This method is capable of directly characterizing metal films with curved surfaces: this is very hard to perform by use of the conventional optical techniques of reflectometry and ellipsometry. The theoretical errors for the experimental fiber are estimated to be within d +/- 2%, epsilon(r) +/- 1%, and epsilon(i) +/- 15%.

1. In this study, we investigated the effects of different drugs (a kappa-opioid receptor agonist U-50,488, a vasopressin receptor antagonist dPTyr(Me)AVP or an N-methyl-D-aspartate (NMDA) receptor antagonist MK-801) on the development of morphine tolerance in rat hippocampal slices. 2. Hippocampal slices (450 microm) of Sprague-Dawley rats (250-300 g) were used. Slices were continuously superfused with artificial CSF or drugs at 1 ml min(-1). Nichrome wire electrodes were placed in the Schaffer-collateral pathway and used to deliver biphasic 0.2 ms pulses of 5-30 V (0.033 Hz). A glass microelectrode was placed in the CA1 area to record population spikes. 3. When the slices were superfused with 10 microM morphine, the amplitude of population spikes increased 2-3 fold in 30-40 min. However, this effect of morphine decreased, i.e. tolerance developed after continuous superfusion of morphine for 2-6 h. 4. When either U-50,488 (200 nM) or dPTyr(Me) AVP (500 pM) or MK-801 (500 pM) was co-superfused with morphine (10 microM), it significantly blocked the development of morphine tolerance. Nor-BNI (a kappa-opioid receptor antagonist, 200 nM) significantly reversed the inhibitory effect of U-50,488 but not those of dPTyr(Me)AVP or MK-801 on the development of morphine tolerance. 5. These data indicate that kappa-opioid receptors, AVP receptors and NMDA receptors are all involved in the development of morphine tolerance. The suppression of kappa-opioid receptor activity after chronic morphine may occur before the activation of AVP receptors or NMDA receptors during the development of morphine tolerance.