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51.
Infective stage Neoaplectana carpocapsae were applied to a furrow of loam soil in the field. At regular intervals over a 7-week period, soil samples were taken at distances of 0, 10, 20, 30, and 40 cm on either side of the furrow. Live, infective nematodes were recovered from the soil at all sampling dates over the 7-week period, and nematodes slowly spread out from the original line of application, averaging a distance of 4.35 cm/day. 相似文献
52.
We are employing a number of selective in vitro and in vivo methods including NMR to screen compounds that bind to heme oxygenases
from pathogenic bacteria. We report the nearly complete HN, N, CO, Cα and Cβ chemical shift assignments of a 215-amino acid
HO from Corynebacterium diphtheria in three forms, apo cd-HO-G135A, apo cd-HO and CO-bound ferrous holo cd-HO; these assignments will enable us to identify residues on cd-HO that are perturbed upon binding to selected compounds, and to help with the development of inhibitors specific to the
bacterial proteins. 相似文献
53.
Background
Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India 相似文献54.
Joshua G. Schraiber Angela N. Kaczmarczyk Ricky Kwok Miran Park Rachel Silverstein Florentine U. Rutaganira Taruna Aggarwal Michael A. Schwemmer Carole L. Hom Richard K. Grosberg Sebastian J. Schreiber 《Journal of theoretical biology》2012
Dengue fever, a viral disease spread by the mosquito Aedes aegypti, affects 50–100 million people a year in many tropical countries. Because the virus must incubate within mosquito hosts for two weeks before being able to transmit the infection, shortening the lifespan of mosquitoes may curtail dengue transmission. We developed a continuous time reaction-diffusion model of the spatial spread of Wolbachia through a population of A. aegypti. This model incorporates the lifespan-shortening effects of Wolbachia on infected A. aegypti and the fitness advantage to infected females due to cytoplasmic incompatibility (CI). We found that local establishment of the Wolbachia infection can occur if the fitness advantage due to CI exceeds the fitness reduction due to lifespan-shortening effects, in accordance with earlier results concerning fecundity reduction. However, spatial spread is possible only if the fitness advantage due to CI is twice as great as the fitness reduction due to lifespan shortening effects. Moreover, lifespan-shortening and fecundity-reduction can have different effects on the speed of wave-retreat. Using data from the literature, we estimated all demographic parameters for infected and uninfected mosquitoes and computed the velocities of spread of infection. Our most optimistic estimates suggest that the spatial spread of lifespan-shortening Wolbachia may be so slow that efficient spatial spread would require a prohibitively large number of point releases. However, as these estimates of demographic parameters may not accurately reflect natural conditions, further research is necessary to corroborate these predictions. 相似文献
55.
K. George L. H. Ziska J. A. Bunce B. Quebedeaux J. L. Hom J. Wolf J. R. Teasdale 《Oecologia》2009,159(3):637-647
To examine the impact of projected climate changes on secondary succession, we exposed the same fallow soil with a common
seed bank to an in situ gradient of urban to rural macroenvironments that differed in temperature and CO2 concentration ([CO2]). This gradient was established at three locations: Baltimore city center (urban), a city park on the outskirts of Baltimore
(suburban), and an organic farm 87 km from the Baltimore city center site (rural). Over a five-year period, the urban site
averaged 2.1°C warmer and had a [CO2] that was ~20% higher than at the rural location, indicating that this gradient was a reasonable surrogate for projected
changes in those variables for this century. Previous work had demonstrated that other abiotic variables measured across the
transect, including tropospheric ozone and nitrogen deposition, did not differ consistently. The first year of exposure resulted
in (two- to threefold) greater aboveground biomass in the urban relative to the rural site, but with uniform species composition
across sites. Simple regression of abiotic variables indicated that temperature and vapor pressure deficit (VPD) were the
best predictors of plant biomass among locations. Stepwise multiple regressions were also performed to analyze the effect
of more than one macroenvironmental variable on total plant biomass. The combination of daily CO2 concentration and nighttime temperature explained 87% (P < 0.01) of the variability in total biomass between sites. After five years, the species demography of the plant communities
had changed significantly, with a greater ratio of perennials to annuals for the urban relative to the rural location. Greater
first-year biomass and litter accumulation at the urban site may have suppressed the subsequent seed germination of annual
species, accelerating changes in species composition. If urban macroenvironments reflect future global change conditions,
these data suggest a faster rate of secondary succession in a warmer, higher [CO2] world. 相似文献
56.
Simeon Bowers Gary D. Probst Anh P. Truong Roy K. Hom Andrei W. Konradi Hing L. Sham Albert W. Garofalo Karina Wong Erich Goldbach Kevin P. Quinn John-Michael Sauer William Wallace Lan Nguyen Susanna S. Hemphill Michael P. Bova Guriqbal S. Basi 《Bioorganic & medicinal chemistry letters》2009,19(24):6952-6956
The structural modification of a series of [3.3.1] bicyclic sulfonamide based γ-secretase inhibitors is described. Appropriate substitution on the bicyclic scaffold provides a significant increase in the metabolic stability of the compounds resulting in an improved in vivo metabolic profile. 相似文献
57.
Anh P. Truong Danielle L. Aubele Gary D. Probst Martin L. Neitzel Chris M. Semko Simeon Bowers Darren Dressen Roy K. Hom Andrei W. Konradi Hing L. Sham Albert W. Garofalo Pamela S. Keim Jing Wu Michael S. Dappen Karina Wong Erich Goldbach Kevin P. Quinn John-Michael Sauer Elizabeth F. Brigham William Wallace Guriqbal Basi 《Bioorganic & medicinal chemistry letters》2010,20(24):7553
58.
Anh P. Truong Gergley Tóth Gary D. Probst Jennifer M. Sealy Simeon Bowers David W.G. Wone Darren Dressen Roy K. Hom Andrei W. Konradi Hing L. Sham Jing Wu Brian T. Peterson Lany Ruslim Michael P. Bova Dora Kholodenko Ruth N. Motter Frédérique Bard Pamela Santiago Huifang Ni David Chian John-Michael Sauer 《Bioorganic & medicinal chemistry letters》2010,20(21):6231-6236
In this Letter, we describe our efforts to design HEA BACE-1 inhibitors that are highly permeable coupled with negligible levels of permeability-glycoprotein activity. These efforts culminate in producing 16 which lowers Αβ by 28% and 32% in the cortex and CSF, respectively, in the preclinical wild type Hartley guinea pig animal model when dosed orally at 30 mpk BID for 2.5 days. 相似文献
59.
Anh P. Truong Gary D. Probst Jose Aquino Larry Fang Louis Brogley Jennifer M. Sealy Roy K. Hom John A. Tucker Varghese John Jay S. Tung Michael A. Pleiss Andrei W. Konradi Hing L. Sham Michael S. Dappen Gergley Tóth Nanhua Yao Eric Brecht Hu Pan Dean R. Artis Lany Ruslim John-Michael Sauer 《Bioorganic & medicinal chemistry letters》2010,20(16):4789-4794
Herein we describe further evolution of hydroxyethylamine inhibitors of BACE-1 with enhanced permeability characteristics necessary for CNS penetration. Variation at the P2′ position of the inhibitor with more polar substituents led to compounds 19 and 32, which retained the potency of more lipophilic analog 1 but with much higher observed passive permeability in MDCK cellular assay. 相似文献
60.
The scientific and medical community remains skeptical regarding the efficacy of nutrition for osteoarthritis despite their
broad acceptation by patients. In this context, this paper systematically reviews human clinical trials evaluating the effects
of nutritional compounds on osteoarthritis. We searched the Medline, Embase, and Biosis databases from their inception to
September 2005 using the terms random, double-blind method, trial, study, placebo, and osteoarthritis. We selected all peer-reviewed
articles reporting the results of randomised human clinical trials (RCTs) in osteoarthritis that investigated the effects
of oral interventions based on natural molecules. Studies on glucosamine and chondroitin sulfate were excluded. The quality
of the RCTs was assessed with an osteoarthritic-specific standardised set of 12 criteria and a validated instrument. A best-evidence
synthesis was used to categorise the scientific evidence behind each nutritional compound as good, moderate, or limited. A
summary of the most relevant in vitro and animal studies is used to shed light on the potential mechanisms of action. Inclusion criteria were met by 53 RCTs out
of the 2,026 identified studies. Good evidence was found for avocado soybean unsaponifiables. Moderate evidence was found
for methylsulfonylmethane and SKI306X, a cocktail of plant extracts. Limited evidence was found for the Chinese plant extract
Duhuo Jisheng Wan, cetyl myristoleate, lipids from green-lipped mussels, and plant extracts from Harpagophytum procumbens. Overall, scientific evidence exists for some specific nutritional interventions to provide symptom relief to osteoarthritic
patients. It remains to be investigated whether nutritional compounds can have structure-modifying effects. 相似文献