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981.
Yehya Alattal Ahmad Al Ghamdi Mohamad Al Sharhi Stephan Fuchs 《Zoology in the Middle East.》2013,59(3):226-235
The rediscovery of the Minor Snake-eyed Skink, Ablepharus grayanus, from two different localities in Sistan and Baluchestan and Kerman Provinces, southeastern Iran is reported. A total of 24 specimens was examined based on morphometrics, colour pattern and pholidotic characters. One-way analyses of variance (ANOVA) based on morphometric measurements revealed significant differences in terms of the snoutvent length (SVL) and fore- and hind limb distances (GA) between eastern and western populations of Ablepharus pannonicus. The most distinguishing characters of Ablepharus grayanus are morphological features, especially ear opening status and scales around the midbody (18-20 versus 20-22). Based on morphological grounds, Ablepharus grayanus is clearly distinguished from A. pannonicus occurring in the eastern and western regions of the Iranian Plateau. 相似文献
982.
Anna Fleischhackerová Pavol Farkaš Alžbeta Čížová Slavomír Bystrický 《Bioscience, biotechnology, and biochemistry》2013,77(11):1817-1824
A glycoconjugate construct was based on attachment of V. cholerae O139 hydrazine-treated lipopolysaccharide (LPS) to carboxylated bovine serum albumin (CBSA) via its amino group. The immunological properties of the glycoconjugate were tested using BALB/c mice, injected subcutaneously without any adjuvant three times at 2?weeks interval. The immunogenicity of the conjugate was estimated by enzyme-linked immunosorbent assay, testing of anti-LPS IgG, IgM, and IgA antibodies. The conjugate elicited a statistically significant increase of LPS-specific IgG levels in mice (p?<?0.001). The specific anti-LPS IgG and IgA response after the second booster dose was significantly higher compared with reference and unconjugated detoxified LPS response. Antibodies elicited by the dLPS–CBSA conjugate were vibriocidal. 相似文献
983.
Zelalem Mersha Shouan Zhang Yuqing Fu Xiaodan Mo Richard N. Raid Bernhard Hau 《Journal of Phytopathology》2013,161(3):154-164
Downy mildew, caused by the oomycete pathogen Peronospora belbahrii, is a devastating foliar disease of basil in the United States and worldwide. Currently there are very few chemistries or organic choices registered to control this disease. In this study, two systemic acquired resistance (SAR) inducers, acibenzolar‐S‐methyl (ASM) and β‐aminobutyric acid (BABA), were evaluated for their in vitro effects on the pathogen, for their potential to control basil downy mildew in greenhouses, and for changes in peroxidase activity in basil plants treated with these two SAR inducers. No significant inhibition of sporangial germination was detected in water agar amended with ASM at concentrations lower than 100 mg/l or with BABA at concentrations lower than 500 mg/l. Efficacy of ASM and BABA in greenhouses varied depending on the rate, method and timing of application. The area under the disease progress curve (AUDPC) of disease severity was significantly reduced compared to the non‐treated control when ASM was sprayed (in all experiments) or drenched (in one out of two experiments) pre‐, or pre‐ + post‐inoculation at rates of 25–400 mg/l. Three weekly post‐inoculation sprays of ASM at the rate of 50 mg/l reduced AUDPC by 93.0 and 47.2% when started 3 and 7 days after inoculation (DAI), respectively. The AUDPC of disease severity was also significantly reduced when BABA was sprayed pre‐ + post‐inoculation at rates of 125–500 mg/l. According to the prediction using a log‐logistic function, 50% maximum disease protection was achieved at a concentration of 27.5 mg/l of ASM. Basil plants treated with these two SAR inducers and challenged with the pathogen showed significantly higher peroxidase activity than the non‐treated control at 8 DAI. Temporally, the highest activity of peroxidase was detected at 8 DAI, decreased at 15 DAI and waned further at 23 DAI. 相似文献
984.
Dennis Imes Patrick Mumm Jennifer Böhm Khaled A. S. Al‐Rasheid Irene Marten Dietmar Geiger Rainer Hedrich 《The Plant journal : for cell and molecular biology》2013,74(3):372-382
Under drought stress, the stress hormone ABA addresses the SnR kinase OST1 via its cytosolic receptor and the protein phosphatase ABI1. Upon activation, OST1 phosphorylates the guard cell S–type anion channel SLAC1. Arabidopsis ABI1 and OST1 loss‐of‐function mutants are characterized by an extreme wilting 'open stomata′ phenotype. Given the fact that guard cells express both SLAC‐ and R–/QUAC‐type anion channels, we questioned whether OST1, besides SLAC1, also controls the QUAC1 channel. In other words, are ABI1/OST1 defects preventing both of the guard cell anion channel types from operating properly in terms of stomatal closure? The activation of the R–/QUAC‐type anion channel by ABA signaling kinase OST1 and phosphatase ABI1 was analyzed in two experimental systems: Arabidopsis guard cells and the plant cell‐free background of Xenopus oocytes. Patch‐clamp studies on guard cells show that ABA activates R–/QUAC‐type currents of wild‐type plants, but to a much lesser extent in those of abi1–1 and ost1–2 mutants. In the oocyte system the co‐expression of QUAC1 and OST1 resulted in a pronounced activation of the R–type anion channel. These studies indicate that OST1 is addressing both S–/SLAC‐ and R–/QUAC‐type guard cell anion channels, and explain why the ost1–2 mutant is much more sensitive to drought than single slac1 or quac1 mutants. 相似文献
985.
Raid A Al-akeel Talat A El-kersh Yazeed A Al-Sheikh Ziab Zakey Al-Ahmadey 《Bioinformation》2013,9(7):357-362
Biofilm formation by Candida species is a major contribute to their pathogenic potential.The aim of this study was to determine in
vitro effects of EDTA, cycloheximide, and heparin-benzyl alcohol preservative on C. albicans (126) and non-albicans (31)vaginal
yeast isolates biofilm formations and their susceptibility against three antifungal Etest strips. Results of the crystal violet-assay,
indicated that biofilms formation were most commonly observed [100%] for C. kefyr, C. utilis, C. famata, and Rhodotorula
mucilaginosa, followed by C. glabrata [70%], C. tropicalis [50%], C. albicans [29%], Saccharomyces cerevisiae [0.0%]. EDTA (0.3mg/ml)
significantly inhibited biofilm formation in both C. albicans and non-albicans isolates (P=0.0001) presumably due to chelation of
necessary metal cations for the process-completion. In contrast, heparin (-benzyl alcohol preservative) stimulated biofilm formation
in all tested isolates, but not at significant level (P=0.567). Conversely, cycloheximide significantly (P=0.0001) inhibited biofilm
formation in all C. albicans strains(126) and its effect was even 3 fold more pronounced than EDTA inhibition, probably due to its
attenuation of proteins (enzymes) and/or complex molecules necessary for biofilm formation. Results also showed that all nonalbicans
yeasts isolates were susceptible to 5-flucytosine (MIC50, 0.016 µg/ml; MIC90, 0.064 µg/ml), but 14% of C. albicans isolates
were resistant (MIC50, 0.064 µg/ml; MIC90 >32 µg/ml). The MIC50 value of amphotricin B for all C. albicans and non-albicans isolates
was at a narrow range of 0.023 µg /ml, and the MIC90 values were 0.047 µg/ml and 0.064 µg/ml respectively, thereby confirming
its efficacy as a first line empiric- treatment of Candida spp infections. 相似文献
986.
Carlos Azevedo Marcela Videira Graça Casal Patrícia Matos Elsa Oliveira Saleh Al‐Quraishy Edilson Matos 《The Journal of eukaryotic microbiology》2013,60(5):490-496
A fish infecting myxosporean Ellipsomyxa gobioides n. sp. is described in the gallbladder of the Amazonian dragon fish Gobioides broussonnetii. Irregular disporous plasmodia (up to ~30 μm in diameter) with long branched and anastomosed pseudopodia were found attached to the gallbladder wall. Mature ellipsoid myxospores occurring floating in the bile measured 6.8 (6.5–7.0) μm (n = 30) long, 7.2 (6.9–7.5) μm (n = 15) wide, and 13.1 (12.8–13.5) (n = 25) thick. They had smooth thin valves elongated in the direction perpendicular to the plane of the straight central transverse sutural line. The two ellipsoidal polar capsules (PC) opened some distance from the sutural line on opposite sides, each measuring 4.6 (4.3–4.8) μm (n = 15) long and 2.5 (2.1–2.7) μm (n = 20) wide. Distance between PC 3.5 (3.1–3.8) μm (n = 15) in apical view. The polar filament was isofilar and consisted of a single coil with five or six turns. The objective of this study was to characterize this new species based on its morphological differences from the three previously described species. This is the first reported species of genus Ellipsomyxa from among the South American fauna. 相似文献
987.
Robert Al‐Chokhachy Jay Alder Steven Hostetler Robert Gresswell Bradley Shepard 《Global Change Biology》2013,19(10):3069-3081
We combine large observed data sets and dynamically downscaled climate data to explore historic and future (2050–2069) stream temperature changes over the topographically diverse Greater Yellowstone Ecosystem (elevation range = 824–4017 m). We link future stream temperatures with fish growth models to investigate how changing thermal regimes could influence the future distribution and persistence of native Yellowstone cutthroat trout (YCT) and competing invasive species. We find that stream temperatures during the recent decade (2000–2009) surpass the anomalously warm period of the 1930s. Climate simulations indicate air temperatures will warm by 1 °C to >3 °C over the Greater Yellowstone by mid‐21st century, resulting in concomitant increases in 2050–2069 peak stream temperatures and protracted periods of warming from May to September (MJJAS). Projected changes in thermal regimes during the MJJAS growing season modify the trajectories of daily growth rates at all elevations with pronounced growth during early and late summer. For high‐elevation populations, we find considerable increases in fish body mass attributable both to warming of cold‐water temperatures and to extended growing seasons. During peak July to August warming, mid‐21st century temperatures will cause periods of increased thermal stress, rendering some low‐elevation streams less suitable for YCT. The majority (80%) of sites currently inhabited by YCT, however, display minimal loss (<10%) or positive changes in total body mass by midcentury; we attribute this response to the fact that many low‐elevation populations of YCT have already been extirpated by historical changes in land use and invasions of non‐native species. Our results further suggest that benefits to YCT populations due to warmer stream temperatures at currently cold sites could be offset by the interspecific effects of corresponding growth of sympatric, non‐native species, underscoring the importance of developing climate adaptation strategies that reduce limiting factors such as non‐native species and habitat degradation. 相似文献
988.
989.
The carbohydrate-binding sequences of the lectin genes from spring vetchling Lathyrus vernus (L.) Bernh., marsh vetchling L. palustris (L.), and Gmelin's vetchling L. gmelinii (Fitsch) (Fabaceae) were determined. Computer-aided analysis revealed substantial differences between nucleotide and predicted amino acid sequences of the lectin gene regions examined in each of the three vetchling species tested. In the phylogenetic trees based on sequence similarity of carbohydrate-biding regions of legume lectins, the sequences examined formed a compact cluster with the lectin genes of the plants belonging to the tribe Fabeae. In each plant, L. vernus, L. palustris, and L. gmelinii, three different lectin-encoding genes were detected. Most of the substitutions were identified within the gene sequence responsible for coding the carbohydrate-binding protein regions. This finding may explain different affinity of these lectins to different carbohydrates, and as a consequence, can affect the plant host specificity upon development of symbiosis with rhizobium bacteria. 相似文献
990.
Moore FR Al Dujaili EA Cornwell RE Smith MJ Lawson JF Sharp M Perrett DI 《Hormones and behavior》2011,60(3):269-274
The stress-linked version of the immunocompetence handicap hypothesis has been proposed to account for inconsistencies in relationships between testosterone and immune response. The model has received some support from studies demonstrating roles of stress hormones in relationships between testosterone, immune function and secondary sexual ornamentation. Such work, however, has relied on artificial elevation of testosterone so may not reflect relationships in natural populations. We created human male facial stimuli on the basis of naturally co-occurring levels of salivary testosterone and the stress hormone cortisol. In Study 1 we tested female preferences for male faces with cues to combinations of the hormones across the menstrual cycle, and in Study 2 we tested perceptions of health and dominance in a novel set of facial stimuli. Females preferred cues to low cortisol, a preference that was strongest during the fertile phase of the menstrual cycle. The effects of cortisol on attractiveness and perceived health and dominance were contingent upon level of testosterone: the effects of the stress hormone were reduced when testosterone was high. We propose explanations for our results, including low cortisol as a cue to a heritable component of health, attractiveness as a predictor of low social-evaluative threat (and, therefore, low baseline cortisol) and testosterone as a proxy of male ability to cope efficiently with stressors. 相似文献