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ABSTRACT: Human exposure to toxic heavy metals via the food chain is of increasing concern. In the present study, the effects of soil type and genotype on variation in arsenic (As) concentrations of different organs were investigated by using nine rice cultivars grown in two soils, with two levels of As contamination. There were significant genotypic differences (P<0.05) in As concentrations of all organs, and As concentrations of polished grain were significantly affected by genotype and soil type. The As concentration in polished grain was higher in red paddy soil under As treatment, with range from 0.24 to 1.03 mg kg(-1), and the As concentration of three cultivars exceeded the concentration of Chinese Food Hygiene Standard (0.7 mg kg(-1)). The As concentrations in stems, leaves and polished grain were all significantly and positively correlated. The As concentrations in polished grain were positively and significantly (P<0.01) correlated with As root-grain translocation factor. The results indicated that As concentration in grain was partially governed by As uptake and the transfer of As from root to grain. The grain As concentration of the nine cultivars was significantly correlated between the two soil types at different levels of As contamination. Some genotypes, such as japonica rice (e.g. Ning jing 1 and Nan jing 32) had consistently low grain As concentrations. The results suggest the possibility of breeding the As rice cultivars to produce grain for safe consumption from soils with slight and moderate levels of As.
Chemosphere 04/2012; 87(4):384-9. · 3.21 Impact Factor
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ABSTRACT: Nitric oxide (NO) is a cellular signaling molecule and a powerful vasodilator. NO modulates basal pulmonary vascular tone and it is important to reduce blood pressure and to treat hypoxemic respiratory failure, such as persistent pulmonary hypertension (PPHN) in newborns. PPHN is defined as a failure of normal pulmonary vascular adaptation at or soon after birth, resulting in a persisting high pulmonary vascular resistance. iNO therapy decreases the need of extracorporeal membrane oxygenation (ECMO) although it did not reduce mortality of these patients. Severe meconial aspiration syndrome is associated with PPHN, resulting in severe hypoxemia; iNO administration combined with HFV results in ameliorate oxygenation. The cause of hypoxemic respiratory failure in patients with congenital diaphragmatic hernia (CDH) is complex. CDH patients experienced oxygenation improvement after iNO therapy, but they can be often considered iNO poor responders. In some cases iNO therapy can reduce the need of ECMO in presurgical stabilization. The pathophysiology of respiratory failure and the potential risks differ substantially in preterm infants. Pulmonary hypertension can complicate respiratory failure in preterm babies. Current evidence does not support use of iNO in early routine, early rescue or layer rescue regimens in the care of preterm infants.
The journal of maternal-fetal & neonatal medicine: the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians 02/2012; 25 Suppl 1:47-50. · 1.36 Impact Factor
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ABSTRACT: Cranial visceral afferent nerve transfers information about visceral organs to nucleus tractus solitarii (NTS) by releasing the excitatory neurotransmitter glutamate. Various endogenous modulators affect autonomic reflex responses by changing glutamatergic responses in the NTS. Although the expression of GABA(A) and GABA(B) receptors in glutamatergic terminals is known, their functional contribution on glutamate release is poorly characterized. Here, we used mechanically isolated NTS neurons to examine the mechanisms by which presynaptic GABA(A) and GABA(B) receptors modulate glutamatergic excitatory postsynaptic currents (EPSCs). EPSC were isolated by clamping voltage at equilibrium potential for chloride (-49 mV) without any GABA receptors antagonists. In all neurons, GABA(A) agonist, muscimol (1 and 10 μM), increased EPSC frequency (284.1±57% and 278.4±87% of control, respectively), but the GABA(B) agonist, baclofen (10 μM), decreased EPSC frequency (43±8% of control). The GABA(A) antagonist, gabazine (18 μM), decreased EPSC frequency in 50% of tested neurons, whereas GABA(B) antagonist, CGP (5 μM), increased the EPSC frequency in 36% of tested neurons. External application of GABA (1 and 30 μM) facilitating the EPSC frequency. The facilitation of the GABA(A) receptor-mediated release of glutamate was blocked by Na⁺-K⁺-Cl⁻ cotransporter type 1 antagonist or Na⁺ and Ca²⁺ channel inhibitors indicating GABA(A) presynaptic depolarization. Thus, tonically released GABA activates GABA(A) and GABA(B) receptors to modulate the release of glutamate. These findings provide cellular mechanisms of heterosynaptic GABA-glutamate integration of peripheral visceral afferent signals in the NTS.
Neuroscience 02/2012; 209:39-46. · 3.38 Impact Factor
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ABSTRACT: The processing bias of threat is crucial for survival. However, the neurophysiological underpinnings of this bias are not fully understood. To contribute to a better understanding of the processing bias for threat, both event-related potential (ERP) and event-related oscillation (ERO) analyses were applied to the electroencephalography (EEG) data recorded from subjects while performing a go/no-go variant of the dot-probe task. In the task, subjects responded to the infrequent target stimuli and didn't respond to the standard stimuli. Both target and standard stimuli were preceded by a bilateral picture pair [one emotional (threatening or pleasant) and one neutral] as an emotional cue. The behavioral data and the P1 elicited by standard stimuli didn't show any significant main effect or interaction. The mean amplitude of N1 was greater negative for threatening cues than pleasant cues with the most significant effect in the fronto-central region, indicating a processing bias for threat related to early attention processing. In addition, the theta synchronization was stronger for threatening cues than pleasant cues with significant effect in posterior regions, suggesting that the posterior theta synchronization reflects the evaluation of emotional significance of stimuli. Taken together, the ERP and ERO analyses provide some independent insights into the processing bias for threatening cues and illustrate this bias more comprehensively.
Neuroscience 02/2012; 203:91-8. · 3.38 Impact Factor
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ABSTRACT: We present a diffeomorphic approach for constructing intrinsic shape atlases of sulci on the human cortex. Sulci are represented as square-root velocity functions of continuous open curves in R³, and their shapes are studied as functional representations of an infinite-dimensional sphere. This spherical manifold has some advantageous properties--it is equipped with a Riemannian L² metric on the tangent space and facilitates computational analyses and correspondences between sulcal shapes. Sulcal shape mapping is achieved by computing geodesics in the quotient space of shapes modulo scales, translations, rigid rotations, and reparameterizations. The resulting sulcal shape atlas preserves important local geometry inherently present in the sample population. The sulcal shape atlas is integrated in a cortical registration framework and exhibits better geometric matching compared to the conventional euclidean method. We demonstrate experimental results for sulcal shape mapping, cortical surface registration, and sulcal classification for two different surface extraction protocols for separate subject populations.
IEEE transactions on medical imaging. 02/2012; 31(6):1195-212.
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ABSTRACT: High-temperature titanium alloys are considered as good candidate materials for many aerospace applications. In order to increase
the usable temperatures and oxidation resistance of titanium alloys, plasma spraying thermal barrier coatings (TBCs) on the
titanium alloys is considered as an effective method. The effect of plasma spraying process on microstructure and microhardness
of the titanium alloy (Ti-6.6Al-3.61Mo-1.69Zr-0.28Si in wt.%) was investigated by scanning electron microscope, energy dispersion
analytical X-ray spectroscopy (EDAX) and microhardness test. The results show that the microstructure of the titanium alloy
inside the substrate keeps unchanged after plasma spraying, and no interaction and atomic diffusion happen evidently at the
bond coat/substrate interface. However there exists a thin layer of plastic deformation zone in the substrate beneath the
bond coat/substrate interface after plasma spraying. The residual stresses are induced inside the titanium alloy due to the
thermal expansion mismatch and the temperature gradient inside the substrate during plasma spraying, and lead to generating
microcracks in the surface beneath the bond coat/substrate interface and the increase of microhardness in the substrate.
Journal of Thermal Spray Technology 01/2008; 17(2):284-288. · 1.81 Impact Factor
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ABSTRACT: Rat's pulmonary hypertension was induced by a single subcutaneous injection of monocrotaline. The influences of tetrandrine (Tet) upon the structure of intraacinar pulmonary arteries (IAPA) was studied by light and electron microscopy. The results indicated that Tet reduced the thickness of IAPA medial membrane, the ratio of the thickness of IAPA medial membrane to the diameter of IAPA, the number of circular muscular artery and partially muscular artery about 16.4%, 30.5%, 24.3% and 16.4% respectively, and Tet increased the number of nonmuscular artery about 24.7%. It also decreased the degeneration of IAPA, collagen of medial membrane, prolife-ration and myoid differentiation of the pericyte, and it increased the number of IAPA. The authors discussed why Tet caused such changes.
Hua xi yi ke da xue xue bao = Journal of West China University of Medical Sciences = Huaxi yike daxue xuebao / [bian ji zhe, Hua xi yi ke da xue xue bao bian wei hui] 04/1996; 27(1):59-62.
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ABSTRACT: The effects of Tetrandrine (Tet) on intraacinous pulmonary arteries (IAPA) and bemodynamics were studied by means of a rat pulmonary hypertension model induced by monocrotaline. The results showed that Tet could reduce the contractive pressure of pulmonary artery, right ventricle and right atrium of heart by 28.0%, 28.3%, and 31.5% respectively. It could also decrease the vascular degeneration of endoepithelial cells of IAPA, the endoepithelial subcavity, the collagens of medial membrane and the numbers of smooth muscles of IAPA.
Hua xi yi ke da xue xue bao = Journal of West China University of Medical Sciences = Huaxi yike daxue xuebao / [bian ji zhe, Hua xi yi ke da xue xue bao bian wei hui] 01/1996; 26(4):378-80.
