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Carboxyl/cholinesterase ( CCE) is a large gene family of diverse functions, but in insects its function with respect to catabolism of sex pheromone components and plant volatiles is not well understood. In the present study, we cloned and functionally characterized one putative odorant-degrading enzyme ( ODE) of the CCE family, Sexi CXE14, from Spodoptera exigua. The tissue-temporal expression pattern revealed that the mRNA level of Sexi CXE14 is antennae-enriched, sex equivalent and peaks at 3 days after moth eclosion. Functional study using the recombinant enzyme determined that Sexi CXE14 has high degrading activity ( Vmax) to host plant volatiles, suggesting its role in degradation of these volatiles. In addition, Sexi CXE14 may also play a role in the degradation of sex pheromone components, as the Vmax and affinity parameter ( Km) values with the sex pheromones are similar to those of reported pheromone degrading enzymes ( PDEs). Further analysis of the relationship between substrate structure and enzymatic activity demonstrated that carbon chain length is a major influential factor, while the number of double bonds also affects the enzymatic activity. In addition, Sexi CXE14 displays lower activity at acidic pH levels ( pH 5.0) than in neutral conditions ( pH 6.5). By characterizing this new ODE the present study provides insights in understanding of the high sensitivity of the moth olfactory system. [ABSTRACT FROM AUTHOR]

We report new petrological data on the sapphirine granulite from Tuguiwula in the Inner Mongolia Suture Zone in the North China Craton which further confirm extreme crustal metamorphism associated with collisional orogeny. The peak metamorphic conditions of the rock have been estimated by sapphirine + quartz assemblage at T > 950 °C and P > 7.5 kbar (M1) based on mineral equilibrium modelling in the NCKFMASHTO system. These conditions are slightly lower than those reported in previous studies (~1050 °C and 10.5 kbar) due to the consideration of Fe2O3 content in the sapphirine granulite in this study, although we confirm a peak ultrahigh-temperature metamorphism in this region. The peak event was followed by a cordierite-forming retrograde event (M2), and biotite-forming retrograde stage (M3) which are constrained in the P-T pseudosection by the stability of cordierite (<7.5 kbar) and biotite + sillimanite + K-feldspar (<890 °C). Combining the results of this study and the petrological observations of spinel + quartz assemblage formed prior to sapphirine + quartz, and orthopyroxene + sillimanite + quartz assemblage after sapphirine + quartz reported in previous studies, a counterclockwise P-T history for these rocks is further confirmed, reflecting heat input into the lower crust from asthenospheric upwelling and underplating associated with the Palaeoproterozoic collisional orogeny in the North China Craton. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary The objective of this study was to determine the effects of incremental replacement of dietary linoleic acid by >20-carbon polyunsaturated fatty acids (PUFA) on changes in population of ruminal micro-organisms associated with fibre digestion and biohydrogenation using real-time PCR of bacterial 16S rRNA sequences. Four beef steers with ruminal cannulas were randomly assigned to control (CK, 65:35 forage to concentrate), CK with 3% sunflower oil plus 1% fish oil (S3F1), 2.5% sunflower oil plus 1.5% fish oil (S2.5F1.5) or 2% sunflower oil plus 2% fish oil (S2F2) in a 4 × 4 Latin square design with 21-day periods. Ruminal fluid was collected on day 15 of each period. Compared with CK, oil addition led to lower ruminal acetate and butyrate but greater propionate concentration. DNA copy number of Anaerovibrio lipolytica in ruminal fluid was greater with oil (average 5.38 vs. 3.62 × 105 DNA copy number), particularly with S2F2 relative to CK. Fibrobacter succinogenes and Butyrivibrio fibrisolvens DNA copy number decreased by 74% (1.06 vs. 4.01 × 105) and 39% (5.16 vs. 8.42 × 107) in response to S2F2 compared with CK. DNA copy numbers of Ruminococcus flavefaciens and Ruminococcus albus were not affected by incremental fish oil. Results suggest that greater availability of PUFA with >20 carbons (i.e. eicosapentaenoic acid and docosahexaenoic acid) promoted changes in bacterial populations that are relevant for fibre digestion and biohydrogenation. [ABSTRACT FROM AUTHOR]

Background: To correlate cerebral perfusion and flow patterns after carotid artery revascularization within the circle of Willis (CoW). Methods: Sixty-five patients (male/female ratio: 38/27; mean age: 63.2 ± 8.4 years; range: 44-82 years) with symptomatic carotid artery stenosis underwent magnetic resonance (MR) angiography and perfusion imaging prior to and after carotid artery stenting (CAS). Regions of interest (ROIs) on the MR perfusion maps included the corona radiata (CR), centrum semiovale (CSO), occipital region (O), and basal ganglia region (BA) in both stented and non-stented hemispheres. The non-stented hemisphere was used as internal control. Results: Subjects were assigned to the altered CoW group ( N = 31) vs. the static CoW group ( N = 34). Thirty-one subjects (47.6%) had an altered flow pattern in the CoW after CAS, and thirty-four (52.4%) retained a static CoW configuration. Relative cerebral blood volume (rCBV) interhemispheric index correlated with CoW morphologic alterations after carotid stenting. Altered CoW group had a higher regional interhemispheric index of rCBV in the CR (1.23 ± 0.15 vs. 0.87 ± 0.13; P = 0.03) and basal ganglia (1.25 ± 0.12 vs. 0.91 ± 0.11; P = 0.03) compared to the static group. Conclusions: An association between the regional cerebral blood volume (rCBV) interhemispheric asymmetry and CoW collateralization was observed. In addition, the CR, rather than CSO, was found to have topographic significance. [ABSTRACT FROM AUTHOR]

Gynogenesis was induced by using UV-irradiated spermatozoa of blunt snout bream Megalobrama amblycephala to activate eggs of common carp Cyprinus carpio. The maternal genome was then duplicated by cold shock in 0 to 4° C cold water to retain the second polar body. Two kinds of fry, normal fry and abnormal tortuous fry, were hatched. Their DNA content was measured by flow cytometry. The normal fry were identified as diploid, representing the successful gynogenesis in C. carpio whereas the abnormal tortuous fry were haploid. Ten microsatellite loci were used to study the genetic diversity among C. carpio, diploid gynogenetic C. carpio and unduplicated haploid tortuous fry. The results indicated that the genetic homozygosity of gynogenetic C. carpio was significantly higher than that of C. carpio. The genetic homozygosity of the haploid C. carpio was intermediate between that of gynogenetic C. carpio and C. carpio. It might be easier for the allogenetic DNA fragments to be integrated into the haploid genome than into diploid gynogenetic genome. [ABSTRACT FROM AUTHOR]

Background and Objective: Local persistent infection by Porphyromonas gingivalis leads to inflammatory systemic diseases, such as atherosclerosis. We have reported previously that avirulent P. gingivalis fimbriae-dependent invasion into endothelial cells might be involved in progression of atherosclerosis. Although interleukin-6 (IL-6) regulates progression of atherosclerosis, little is known about the relationship of P. gingivalis fimbriae-dependent invasion to IL-6 regulation in endothelial cells. Material and Methods: We examined the secretion of IL-6 and the expression of the IL-6 signal transducer gp130 in human umbilical vein endothelial cells (HUVEC) infected with the wild-type FDC381 strain of P. gingivalisand a fimbriae-deficient mutant ( fimA) by enzyme-linked immunosorbent assay, quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and flow cytometry (fluorescence-activated cell sorting, FACS) analysis. Results: Coculture of HUVEC with P. gingivalis resulted in increase of IL-6 secretion at 24 h postinfection. Interestingly, the increase was inhibited significantly in HUVEC infected with the P. gingivalis fimA mutant. In addition, the increase of IL-6 secretion induced by P. gingivalis infection was significantly impaired by the meiosis specific kinase 1 inhibitor, PD98059, or the nuclear factor κB inhibitor, Bay11-7082. Furthermore, we demonstrated that gp130 expression increased with P. gingivalis infection. Importantly, gp130 expression was significantly impaired by P gingivalis fimA mutant infection compared with wild-type P. gingivalis infection, as assessed by both quantitative RT-PCR and FACS analysis. Conclusion: Our findings indicate that P. gingivalis fimbriae are important factors in the autocrine regulation of IL-6, by increasing gp130 in endothelial cells. [ABSTRACT FROM AUTHOR]

A high rate of germination at low temperatures is necessary for economic yields to be maintained. In this paper, the genetic control of low temperature germination ability (LTG) was assessed by the measurement of germination rate (GR), germination rate index (GI) and mean germination time (MGT), and genetically mapped using a set of recombinant inbred lines, derived from a cross between the japonica cultivar ‘Asominori’ and the indica cultivar ‘IR24’. Putative quantitative trait loci (QTL) were validated by testing in two related sets of chromosome segment substitution lines (CSSL). In this genetic background, LTG is under the control of a number of QTL, each of relatively small effect, and is spread over six chromosomes. The most stable of these QTL was for GR, mapping to a segment of chromosome 11 which also carries a QTL for GI. On chromosome 2, qGR-2 not only controlled GR, but also was associated with GI and MGT. Significant differences in LTG were detected between ‘Asominori’ and some CSSL harbouring qGR-2 or qGR-11. [ABSTRACT FROM AUTHOR]

Ion-implanted planar-gate power GaAs MESFETs have been optimized for single-voltage-supply operation. Recessed gate MESFETs suffer from variations in pinch-off voltage. The optimized ion-implanted planar-gate power GaAs MESFET has an 80 keV 4.2×1012/cm2 Si channel with a 120 keV 1.7×1012/cm2 Be p-buffer. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 44–46, 2001. [ABSTRACT FROM AUTHOR]

Acuthrombin-B, a thrombin-like enzyme from Agkistrodon acutus venom, has been isolated and purified to homogeneity by ion-exchange chromatography on DEAE-Sepharose, gel filtration on Sephacryl S-100 and fast performance liquid chromatography on DEAE-8HR. The protease is an acid protein (pI 6.0) consisting of two non-identical polypeptide chains (14.4 and 16 kDa) and there is no disulfide bond between the subunits. Its molecular weight is 27 kDa as estimated by gel filtration on Sephacryl S-100. The protease has arginine-esterase activity and hydrolyzes synthetic substrates such as p-toluenesulfonyl arginine methyl ester and alpha-N-benzoyl-L-arginine amide ethyl ester, and shows clotting activity with human fibrinogen, rabbit citrated plasma and human citrated plasma in vitro. The specific activity with human fibrinogen was estimated to be 230 NIH units mg-1. The protease is considered as a serine-type protease and contains metal ion(s) to some extent, as indicated by the fact that its clotting and arginine-esterase activities could be completely inhibited by PMSF and partially inhibited by the chelating agent EDTA, while the thrombin inhibitor heparin had no effect on its clotting activity towards rabbit citrated plasma. Acuthrombin-B crystals with a resolution limit of 2.06 A were obtained by conventional hanging-drop vapour diffusion. The crystals belong to space group P21 with unit-cell parameters a = 34.97, b = 53.58, c = 67.88 A, beta = 98.89 degrees and contain one molecule per asymmetric unit.

To clarify the effects of lead on autonomic and central nervous system functions, electrocardiographic R-R interval variability (CVRR) as well as visual and brainstem auditory evoked potentials (VEP and BAEP) were measured in 36 female workers exposed to lead (exposed group) and in 15 female textile workers (unexposed group). The C-CVLF, C-CVHF (two component CVs of the CVRR reflecting sympathetic and parasympathetic activities, respectively), and LF/HF ratio (indicator of sympatho-vagal balance) were also computed from component spectral powers by means of autoregressive spectral and component analyses. The exposed group had engaged in glass work for 2-17 (mean 7.8) years. Blood lead (BPb) concentrations were 25.8-79.3 (mean 55.6) micrograms/dl in the exposed group and 4.7-8.6 (mean 6.3) micrograms/dl in the unexposed group. The CVRR, C-CVLF, C-CVHF, and LF/HF ratio in the exposed group were significantly lower than those in the unexposed group. Also, the exposed group had more complaints of subjective symptoms and signs than did the unexposed group. On the other hand, no significant differences in either VEP or BAEP latencies were found between the two groups. It is suggested that autonomic nervous function is more susceptible to lead than visual and auditory nervous functions; lead affects sympathetic activity more strongly than parasympathetic activity.

A factory survey was conducted in three provinces in China from 1985 to 1989. The time-weighted average toluene concentrations in breathing zone air were monitored by diffusive sampling, whereas hippuric acid (HA) concentrations in shift-end urine samples were measured by high performance liquid chromatography (HPLC). Exposed workers (456 men and women) were those for whom toluene (up to 548 ppm toluene) accounted for greater than or equal to 90% of total exposure (by vapor concentration in ppm), whereas 517 nonexposed controls were recruited from the same factories or from factories of the same region. There was a linear correlation between the intensity of toluene exposure and HA concentration in the shift-end urine. Comparison of the results with findings in the literature shows that the toluene-induced increase in urinary HA concentration among workers in China is significantly smaller than the published values, whereas HA concentrations in urine samples from nonexposed controls are comparable to the levels previously reported.