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61.
Özen Özensoy Semra Isik Oktay Arslan Mikail Arslan Andrea Scozzafava Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):383-387
The purification of red blood cell carbonic anhydrase (CA, EC 4.2.1.1) from ostrich (scCA) blood is reported, as well as an inhibition study of this enzyme with a series of aromatic and heterocylic sulfonamides. The ostrich enzyme showed a high activity, comparable to that of the human isozyme II, with kcat of 1.2·106 s? 1 and kcat/KM of 1.8·107 M? 1 s? 1, and an inhibition profile quite different from that of the human red blood cell cytosolic isozymes hCA I and II. scCA has generally a lower affinity for sulfonamide inhibitors as compared to hCA I and II. The only sulfonamide which behaved as a very potent inhibitor of this enzyme was ethoxzolamide (KI = 3.9 nM) whereas acetazolamide and sulfanilamide behaved as weaker inhibitors (inhibition constants in the range 303–570 nM). Several other aromatic and heterocyclic sulfonamides, mostly derivatives of sulfanilamide, homosulfanilamide, 4-aminoethylbenzenesulfonamide or 5-amino-1,3,4-thiadiazole-2-sulfonamide, showed good affinities for the ostrich enzyme, with KI values in the range 25–72 nM. 相似文献
62.
Taryn N. Crepeau Sean P. Healy Kristen Bartlett-Healy Isik Unlu Ary Farajollahi Dina M. Fonseca 《PloS one》2013,8(3)
The Biogents® Sentinel (BGS) trap is the standard tool to monitor adult Aedes (Stegomyia) albopictus (Skuse) (Diptera: Culicidae), the Asian tiger mosquito. BGS traps are commonly placed in residential properties during surveillance operations, but locations within properties may have significant differences in ambient light, temperature, and humidity (e.g. between a sunlit lawn and shady underbrush). We examined the effect of BGS trap placement on Ae. albopictus capture rates in three residential properties in Monmouth County, New Jersey, USA. In each property we visually selected locations as shade, partial shade, and sun. Traps in “partial shade” locations were under vegetation and were exposed to filtered sunlight during some parts of the day while “shaded” locations were never exposed to direct sunlight. Locations defined as “sun” were exposed to direct sunlight for large parts of the day. We placed a BGS trap in each of the three location types and used small data loggers to measure temperature, relative humidity, and light exposure at each trap during a 24-hour deployment. To address temporal variability, we made seven separate measurements from 31 August to 22 September 2010. We found that “partial shade” and “full shade” locations did not differ but that “full sun” locations had significantly higher light exposure, higher temperature, and lower humidity. Importantly, Ae. albopictus catches (males, females, or both) were consistently and significantly over 3 times higher in traps located in shaded locations. To further investigate the effects of local temperature and humidity on surveillance we examined Ae. albopictus collections from 37 BGS traps fitted with data loggers and deployed weekly from August through mid October, during the 2009 season, in three urban sites in Mercer County, NJ. We confirmed that local climate influences capture rates and that Ae. albopictus surveillance projects need to monitor trap placement carefully for maximum efficiency. 相似文献
63.
Ahmed M. Alafeefy Semra Isik Hatem A. Abdel-Aziz Abdelkader E. Ashour Daniela Vullo Nabila A. Al-Jaber Claudiu T. Supuran 《Bioorganic & medicinal chemistry》2013,21(6):1396-1403
A series of benzenesulfonamides incorporating cyanoacrylamide moieties (tyrphostine analogues) have been obtained by reaction of sulfanilamide with ethylcyanoacetate followed by condensation with aromatic/heterocyclic aldehydes, isothiocyanates or diazonium salts. The new compounds have been investigated as inhibitors of the metalloenzyme carbonic anhydrase (CA, EC 4. 2.1.1), and more specifically against the cytosolic human (h) isoforms hCA I and II, as well as the transmembrane, tumor-associated ones CA IX and XII, which are validated antitumor targets. Most of the new benzenesulfonamides were low nanomolar or subnanomolar CA IX/XII inhibitors whereas they were less effective as inhibitors of CA I and II. The structure–activity relationship for this class of effective CA inhibitors is also discussed. Generally, electron donating groups in the starting aldehyde reagent favored CA IX and XII inhibition, whereas halogeno, methoxy and dimethylamino moieties led to very potent CA XII inhibitors. 相似文献
64.
Huan Wang Michael Isik Alexander Borst Werner Hemmert 《Journal of computational neuroscience》2011,30(3):529-542
In this paper we use information theory to quantify the information in the output spike trains of modeled cochlear nucleus
globular bushy cells (GBCs). GBCs are part of the sound localization pathway. They are known for their precise temporal processing,
and they code amplitude modulations with high fidelity. Here we investigated the information transmission for a natural sound,
a recorded vowel. We conclude that the maximum information transmission rate for a single neuron was close to 1,050 bits/s,
which corresponds to a value of approximately 5.8 bits per spike. For quasi-periodic signals like voiced speech, the transmitted
information saturated as word duration increased. In general, approximately 80% of the available information from the spike
trains was transmitted within about 20 ms. Transmitted information for speech signals concentrated around formant frequency
regions. The efficiency of neural coding was above 60% up to the highest temporal resolution we investigated (20 μs). The
increase in transmitted information to that precision indicates that these neurons are able to code information with extremely
high fidelity, which is required for sound localization. On the other hand, only 20% of the information was captured when
the temporal resolution was reduced to 4 ms. As the temporal resolution of most speech recognition systems is limited to less
than 10 ms, this massive information loss might be one of the reasons which are responsible for the lack of noise robustness
of these systems. 相似文献
65.
W. Patrick Cumbie Fikret Isik Bailian Li Barry Goldfarb 《Tree Genetics & Genomes》2011,7(6):1147-1158
Nine full-sib families of loblolly pine (Pinus taeda L.) were produced by a 3 × 3 factorial mating design. Rooted cuttings and seedlings of full-sib families were tested together
in two field locations. Twelve-millimeter wood increment cores were collected from 10- and 11-year-old test trees. On each
of the two sites, there were six blocks and a split-plot design, with propagule type as the whole plot and family as the sub-plot.
In addition to the collection of wood samples, height and diameter of 1,600 trees were measured. No significant differences
were found between cuttings and seedlings for wood density and growth traits. Significant family variation was found for growth
and wood density. Genetic parameters estimated for wood density and growth traits using seedlings and rooted cuttings showed
that individual-tree and family heritability estimates from rooted cuttings were similar to or higher than those from seedlings
for all traits. Half-sib breeding values for parents were highly correlated based on seedling and rooted cutting estimates
for height (0.95) and wood density (0.99) but not for diameter (0.56), which suggests that wood density and height breeding
value estimates from rooted cuttings in clonal progeny tests can be estimated by traditional seedling tests, but not for tree
diameter. 相似文献
66.
Yoursy A. El-Kassaby Shawn Mansfield Fikret Isik Michael Stoehr 《Tree Genetics & Genomes》2011,7(3):553-561
The genetic control and phenotypic and genotypic correlations among wood density, modulus of elasticity, height, diameter,
and volume were assessed using 967 trees representing 20 unrelated 32-year-old coastal Douglas-fir full-sib families growing
on four (spaced and pruned vs. control) comparable test sites. Generally, no significant differences were observed between
treatments, indicating their limited effect at assessment time. Family effect did not differ for the growth traits; however,
significant differences were observed for wood density and both in situ methods (drilling resistance and acoustic velocity).
Growth and wood quality attributes, individually, produced high and positive phenotypic and genetic correlations; however,
high and negative correlations were observed between individual variables belonging to the two suites of attributes. Individual
tree heritabilities were low for growth (0.04 to 0.08) and modest to high for wood quality attributes (0.14 to 0.68). The
observed heritabilities and phenotypic and genotypic correlations imply modest to strong genetic control; however, they operated
in opposing direction. The significant and consistent genetic correlations between the in situ methods and wood density and
stiffness support their use as a non-destructive and economic assessment approach. The reliability of the in situ assessments
was verified through cumulative pith-to-bark wood density assessment, resulting in inconsistent genetic and phenotypic correlations
for early growth years. These latter findings imply that caution should be used in employing these in situ techniques as early
screening tools in breeding programs. 相似文献
67.
Nilgun Isik Lewis White Rosemary Barnes Christopher J. Poynton Ken I. Mills 《Molecular biotechnology》2003,24(3):229-231
The clinical management of immunocompromised patients depends on the rapid identification of infectious agents such as fungal
pathogens. The procedure described here for accomplishing this uses a sensitive polymerase chain reaction method, previously
reported, combined with restriction-enzyme digestion to distinguish between Candida and Aspergillus species and to classify Aspergillus strains. 相似文献
68.
Semra Isik Feray Kockar Meltem Aydin Oktay Arslan Ozen Ozensoy Guler Alessio Innocenti Andrea Scozzafava Claudiu T. Supuran 《Bioorganic & medicinal chemistry》2009,17(3):1158-1163
The protein encoded by the Nce103 gene of Saccharomyces cerevisiae, a β-carbonic anhydrase (CA, EC 4.2.1.1) designated as scCA, has been cloned, purified, characterized kinetically and investigated for its inhibition with a series of sulfonamides and one sulfamate. The enzyme showed high CO2 hydrase activity, with a kcat of 9.4 × 105 s?1, and kcat/KM of 9.8 × 107 M?1 s?1. Simple benzenesulfonamides substituted in 2-, 4- and 3,4-positions of the benzene ring with amino, alkyl, halogeno and hydroxyalkyl moieties were weak scCA inhibitors with KIs in the range of 0.976–18.45 μM. Better inhibition (KIs in the range of 154–654 nM) was observed for benzenesulfonamides incorporating aminoalkyl/carboxyalkyl moieties or halogenosulfanilamides; benzene-1,3-disulfonamides; simple heterocyclic sulfonamides and sulfanilyl-sulfonamides. The clinically used sulfonamides/sulfamate (acetazolamide, ethoxzolamide, methazolamide, dorzolamide, topiramate, celecoxib, etc.) generally showed effective scCA inhibitory activity, with KIs in the range of 82.6–133 nM. The best inhibitor (KI of 15.1 nM) was 4-(2-amino-pyrimidin-4-yl)-benzenesulfonamide. These inhibitors may be useful to better understand the physiological role of β-CAs in yeast and some pathogenic fungi which encode orthologues of the yeast enzyme and eventually for designing novel antifungal therapies. 相似文献
69.
The Cry3Bb1 protein, insecticidal to the corn rootworm complex (Diabrotica spp.), of Bacillus thuringiensis (Bt) subsp. kumamotoensis was released in root exudates of transgenic Bt corn (event MON863) in sterile hydroponic culture (7.5 +/- 1.12 ng/ml after 28 days of growth) and in nonsterile soil throughout growth of the plants (2.2 +/- 0.62 ng/g after 63 days of growth). Kitchawan soil, which contains predominantly kaolinite (K) but not montmorillonite (M), was amended to 3 or 6% (vol./vol.) with K (3K and 6K soils) or M (3M and 6M soils) and with 1, 3, 5, or 10% (wt./wt.) of ground biomass of Bt corn expressing the Cry3Bb1 protein and incubated at 25 +/- 2 degrees C at the -33-kPa water tension for 60 days. Soils were analyzed for the presence of the protein every 7 to 10 days with a western blot assay (ImmunoStrip) and verified by ELISA. Persistence of the protein varied with the type and amount of clay mineral and the pH of the soils and increased as the concentration of K was increased but decreased as the concentration of M was increased. Persistence decreased when the pH of the K-amended soils was increased from ca. 5 to ca. 7 with CaCO(3): the protein was not detected after 14 and 21 days in the pH-adjusted 3K and 6K soils, respectively, whereas it was detected after 40 days in the 3K and 6K soils not adjusted to pH 7. The protein was detected for only 21 days in the 3M soil and for 14 days in the 6M soil, which were not adjusted in pH. These results indicate that the Cry3Bb1 protein does not persist or accumulate in soil and is degraded rapidly. 相似文献
70.