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941.
Aim:  To evaluate the microbial disinfection efficacy of a plasmachemical solution obtained by the activation of water with gliding electric discharges.
Methods and Results:  Distilled water was activated for 5 min by a nonthermal quenched plasma of the glidarc type operating in humid air and at atmospheric pressure. The plasma-activated water (PAW) was then used to treat planktonic and adherent cells of Staphylococcus epidermidis , Leuconostoc mesenteroides (as models of Gram-positive bacteria), Hafnia alvei (a Gram-negative bacteria) and Saccharomyces cerevisiae (as a yeast model). The treatments were less efficient on adherent cells than on planktonic cells in the case of bacteria, but not of S. cerevisiae . Inactivation was more effective for bacteria than for the yeast.
Conclusions:  Significant reductions in microbial populations were achieved in all cases, demonstrating the effectiveness of this new approach to treat contaminated media.
Significance and Impact of the Study:  PAW is a promising solution with potential application to the decontamination of equipment and surfaces.  相似文献   
942.
The phylogenetic relationship for classification traits and eight mineral elements in brown rice (Oryza sativa L.) from Yunnan Province in China was carried out using microwave assisted digestion followed by inductively coupled plasma atomic emission spectroscopy, and the analytical procedures were carefully controlled and validated. In general, the results show that the mean levels of K, Ca, Mg, Fe and Cu in brown rice for 789 accessions of rice landraces was distinctly lower than that of improved cultivars. They further demonstrate that Ca plays an important role in the differentiation of subspecies indica-japonica, especially to enhance adaptation of cold stress, and that five mineral elements in brown rice enhance the eurytopicity from landrace to improved cultivar. Hierarchical cluster analysis, using average linkage from SPSS software based on eight mineral elements in brown rice, showed that Yunnan rice could be grouped into rice landrace and improved cultivar, with the rice landrace being further clustered into five subgroups, and that, interestingly, purple rice does not cluster with either of the groups. Our present data confirm that indica is the closest relative of late rice and white rice, and that they constitute rice landraces together, whereas japonica is the closest relatives of non-nuda, early-mid and glutinous rice. It is further shown that japonica, non-nuda, early-mid, glutinous, white and red rice might be more primitive than indica, nuda, late, non-glutinous and purple rice, respectively.  相似文献   
943.
944.
Familial resemblance in the second‐to‐fourth digit ratio (2D:4D), a proxy for prenatal androgen action, was studied in 1,260 individuals from 235 Austrian families. In agreement with findings from twin studies of 2D:4D, heritability estimates based on parent–child and full‐sib dyad similarity indicated substantial genetic contributions to trait expression (57% for right hand, 48% for left hand 2D:4D). Because twin studies have found nonadditive genetic as well as shared environmental effects on 2D:4D to be negligible or nil, these family‐based estimates in all likelihood reflect the narrow‐sense (additive genetic) heritability of the trait. Directional (right‐minus‐left) asymmetry in 2D:4D was only weakly heritable (6%). The pattern of same‐sex and different‐sex parent–child and full‐sib correlations yielded no evidence for X‐linked inheritance. This is surprising, considering evidence for associations of male 2D:4D with sensitivity to testosterone (functional variants of the X‐linked androgen receptor gene). 2D:4D was particularly strongly heritable through male lines (father–son and brother–brother correlations), thus raising the possibility that Y‐linked genes (such as the sex‐determining region SRY) might influence 2D:4D expression. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
945.
The effect of non-ionic detergents on baclofen (GABAB-R agonist)-stimulated G-protein activity was measured as a [35S]GTPγS binding assay in the plasma membranes (PM) isolated from the brain tissue. The effect was clearly biphasic — a decrease in the activity was followed by an activation maximum and finally, at high concentrations, drastic inhibition of the G-protein activity was noticed. Contrarily, specific radioligand binding to GABAB-receptor was inhibited in the whole range of detergent concentrations step by step, i.e. it was strictly monophasic. The magnitude of both detergent effects was decreased in the same order of potency: Brij58 > Triton X-100 > Digitonin. The identical order was found when comparing detergents ability to alter fluorescence anisotropy of the membrane probe 1,6-diphenyl-1,3,5-hexatriene (rDPH) incorporated into the hydrophobic PM interior. Decrease of rDPH, in the order of Brij58 > Triton X-100 > Digitonin, was reflected as decrease of the S-order parameter and rotation correlation time ? paralleled by an increase of diffusion wobbling constant Dw (analysis by time-resolved fluorescence according to “wobble-in-cone” model). The influence of the detergents on the membrane organization at the polar headgroup region was characterized by Laurdan generalized polarization (GP). As before, the effect of detergents on GP parameters proceeded in the order: Brij58 > Triton X-100 > Digitonin.  相似文献   
946.
Broadly neutralizing anti-hepatitis B virus (HBV) antibody HzKR127 undergoes a fairly large conformational change of CDR H3 loop upon binding to HBV preS1 epitope peptide. In this study, we identified low-affinity antibody-binding sites in the largely unstructured preS1 region by nuclear magnetic resonance and biochemical studies, indicating that the antibody binds to the preS1 region outside the major immune epitope with low affinity. Surface plasma resonance experiments showed that the full-length preS1 has approximately three fold higher affinity for HzKR127 Fab than the preS1 epitope peptide, suggesting that the presence of low-affinity sites in the preS1 region increases the antibody-binding affinity. Therefore, the low-affinity binding of the antibody to non-epitope regions of preS1 may contribute to effective neutralization.  相似文献   
947.
αB-crystallin, a low-molecular-weight heat shock protein (HSP), has binding sites on platelets. However, the exact role of αB-crystallin is not clarified. In this study, we investigated the effect of αB-crystallin on platelet granule secretion. αB-crystallin attenuated the adenosine diphosphate (ADP)-induced phosphorylation of p44/p42 mitogen-activated protein kinase (MAPK) and p38 MAPK. The ADP-stimulated HSP27 phosphorylation was markedly reduced by αB-crystallin. αB-crystallin significantly suppressed the ADP-induced secretions of both platelet-derived growth factor (PDGF)-AB and serotonin. Therefore, our results strongly suggest that αB-crystallin extracellularly suppresses platelet granule secretion by inhibition of HSP27 phosphorylation via p44/p42 MAPK and p38 MAPK.  相似文献   
948.
Oxidized-1-palmitoyl-2-arachidonyl-sn-glycerol-3-phosphocholine (Ox-PAPC) has been demonstrated to accumulate in atherosclerotic lesions and regulates expression of more than 1,000 genes in human aortic endothelial cell (HAEC). Among the most highly induced is heme oxygenase-1 (HO-1), a cell-protective antioxidant enzyme, which is sensitively induced by oxidative stress. To identify the pathway by which Ox-PAPC induces HO-1, we focused on the plasma membrane electron transport (PMET) complex, which contains ecto-NADH oxidase 1 (eNOX1) and NADPH:quinone oxidoreductase 1 (NQO1) and affects cellular redox status by regulating levels of NAD(P)H. We demonstrated that Ox-PAPC and its active components stimulated electron transfer through the PMET complex in HAECs from inside to outside [as determined by extracellular 2-(4-iodophenyl)-3-(44-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium (WST-1) reduction] and from outside to inside of the cell (as determined by intracellular NBT reduction). Chemical inhibitors of PMET system and siRNAs to PMET components (NQO1 and eNOX1) significantly decreased HO-1 induction by Ox-PAPC. We present evidence that Ox-PAPC activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in HAEC plays an important role in the induction of HO-1 and PMET inhibitors blocked Nrf2 activation by Ox-PAPC. We hypothesized that PMET activation by Ox-PAPC causes intracellular NAD(P)H depletion, which leads to the increased oxidative stress and HO-1 induction. Supporting this hypothesis, cotreatment of cells with exogenous NAD(P)H and Ox-PAPC significantly decreased oxidative stress and HO-1 induction by Ox-PAPC. Taken together, we demonstrated that the PMET system in HAEC plays an important role in the regulation of cellular redox status and HO-1 expression by Ox-PAPC.  相似文献   
949.
The structure-activity relationship of 18-carbon fatty acids (C18 FAs) on human neutrophil functions and their underlying mechanism were investigated. C18 unsaturated (U)FAs potently inhibited superoxide anion production, elastase release, and Ca2+ mobilization at concentrations of <10 μM in formyl-l-methionyl-l-leucyl-l-phenylalanine (FMLP)-activated human neutrophils. However, neither saturated FA nor esterified UFAs inhibited these neutrophil functions. The inhibitory potencies of C18 UFAs decreased in the following order: C18:1 > C18:2 > C18:3 > C18:4. Notably, the potency of attenuating Ca2+ mobilization was closely correlated with decreasing cellular responses. The inhibitions of Ca2+ mobilization by C18 UFAs were not altered in a Ca2+-containing Na+-deprived medium. Significantly, C18 UFAs increased the activities of plasma membrane Ca2+-ATPase (PMCA) in neutrophils and isolated cell membranes. In contrast, C18 UFAs failed to alter either the cAMP level or phosphodiesterase activity. Moreover, C18 UFAs did not reduce extracellular Ba2+ entry in FMLP- and thapsigargin-activated neutrophils. In summary, the inhibition of neutrophil functions by C18 UFAs is attributed to the blockade of Ca2+ mobilization through modulation of PMCA. We also suggest that both the free carboxy group and the number of double bonds of the C18 UFA structure are critical to providing the potent anti-inflammatory properties in human neutrophils.  相似文献   
950.
The objective of these studies was to investigate the practicality of flow cytometric sex-sorting for spermatozoa from the white and the black rhinoceros (Ceratotherium simum, Diceros bicornis). In Experiment 1, four semen extenders were tested regarding their suitability for liquid preservation of spermatozoa before sorting. Dilution in MES-HEPES-based semen extender followed by incubation generated best sperm quality parameters (motility, viability, and acrosome integrity). In Experiment 2, the effect of staining method (15 °C for 4 to 6 h during transport or 37 °C for 1 to 1.5 h) on sort efficiency and sperm quality was investigated. Staining at 15 °C during transport resulted in a higher percentage of sperm samples showing a resolution of X- and Y-chromosome-bearing populations (60%) compared with that for staining at 37 °C after transport (33%) and resulted in superior sperm integrity after staining (43.8 ± 11.3% vs. 19.6 ± 12.1%). Sort rate was 300 to 700 cells/sec and sort purity, determined for one sorted sample, was 94% for X-chromosome-bearing spermatozoa. In Experiment 3, the highly viscous component of rhinoceros seminal plasma, which complicates the process of sperm sorting, was examined by gel electrophoresis and mass spectrometry. Results suggested a 250-kDa glycoprotein (most likely originating from the bulbourethral gland) to be responsible for the characteristic viscosity of ejaculates. In Experiment 4, viscosity of seminal plasma, as measured by electron spin resonance spectroscopy, was significantly decreased after addition of α-amylase or collagenase (0.5 and 3 IU per 100 μL seminal plasma, respectively) by 28% and 21%, respectively, with no negative effect on sperm characteristics. The results of this study demonstrate for the first time that rhinoceros spermatozoa can be successfully sorted into high-purity X- and Y-chromosome-bearing populations. Furthermore, the successful liquefaction of viscous ejaculates provides the means to greatly improve sort-efficiency in this species.  相似文献   
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