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991.
992.
Boyan Petkov Vito Vitale Claudio Tomasi Mauro Mazzola Christian Lanconelli Angelo Lupi Maurizio Busetto 《International journal of biometeorology》2014,58(1):31-39
Variations in total ozone column and sun exposures able to cause erythema and damage the DNA molecules were observed by the narrow-band filter radiometer UV-RAD in Bologna, Italy from 2005 to 2010. The ozone columns determined from the UV-RAD measurements were found to be close to those provided by the satellite Ozone Monitoring Instrument (OMI) showing an average discrepancy of 1 % with standard deviation of ± 6 %. Analysis of the data highlights a well-marked annual cycle of the ozone column variations while the oscillations with periods of 8, 18 and 34 months present much smaller amplitudes. The influence of the frequency of solar irradiance measurements on the accuracy of the evaluated daily exposure dose has been studied and it was found that time intervals no longer than 5–10 min between the measurements of erythema and DNA damage effective UV irradiances provide a satisfactory assessment of the corresponding daily exposures. The latter do not present significant year-to-year variations for the period under study, while their annual distributions show slight changes likely due to the specific cloud cover and ozone column variability for different years. The annual erythemal exposure dose for 2007–2010 varied between 603.7 and 638.1 kJ?m?2, while the corresponding sun exposure affecting DNA changed from 6.38 to 7.91 kJ?m?2. 相似文献
993.
Ashini Bolia Brian?W. Woodrum Angelo Cereda Melissa?A. Ruben Xu Wang S. Banu Ozkan Giovanna Ghirlanda 《Biophysical journal》2014,106(5):1142-1151
Cyanovirin-N (CVN), a cyanobacterial lectin, exemplifies a class of antiviral agents that inhibit HIV by binding to the highly glycosylated envelope protein gp120. Here, we investigate the energetics of glycan recognition using a computationally inexpensive flexible docking approach, backbone perturbation docking (BP-Dock). We benchmarked our method using two mutants of CVN: P51G-m4-CVN, which binds dimannose with high affinity through domain B, and CVN(mutDB), in which binding to domain B has been abolished through mutation of five polar residues to small nonpolar side chains. We investigated the energetic contribution of these polar residues along with the additional position 53 by docking dimannose to single-point CVN mutant models. Analysis of the docking simulations indicated that the E41A/G and T57A mutations led to a significant decrease in binding energy scores due to rearrangements of the hydrogen-bond network that reverberated throughout the binding cavity. N42A decreased the binding score to a level comparable to that of CVN(mutDB) by affecting the integrity of the local protein structure. In contrast, N53S resulted in a high binding energy score, similar to P51G-m4-CVN. Experimental characterization of the five mutants by NMR spectroscopy confirmed the binding affinity pattern predicted by BP-Dock. Despite their mostly conserved fold and stability, E41A, E41G, and T57A displayed dissociation constants in the millimolar range. N53S showed a binding constant in the low micromolar range, similar to that observed for P51G-m4-CVN. No binding was observed for N42A. Our results show that BP-Dock is a useful tool for rapidly screening the relative binding affinity pattern of in silico-designed mutants compared with wild-type, supporting its use to design novel mutants with enhanced binding properties. 相似文献
994.
Robert D. Reid Lisa A. McDonnell Dana L. Riley Amy E. Mark Lori Mosca Louise Beaton Sophia Papadakis Chris M. Blanchard Heidi Mochari-Greenberger Patricia O’Farrell George A. Wells Monika E. Slovinec D’Angelo Andrew L. Pipe 《CMAJ》2014,186(1):23-30
Background:
Family members of patients with coronary artery disease (CAD) have higher risk of vascular events. We conducted a trial to determine if a family heart-health intervention could reduce their risk of CAD.Methods:
We assessed coronary risk factors and randomized 426 family members of patients with CAD to a family heart-health intervention (n = 211) or control (n = 215). The intervention included feedback about risk factors, assistance with goal setting and counselling from health educators for 12 months. Reports were sent to the primary care physicians of patients whose lipid levels and blood pressure exceeded threshold values. All participants received printed materials about smoking cessation, healthy eating, weight management and physical activity; the control group received only these materials. The main outcomes (ratio of total cholesterol to high-density lipoprotein [HDL] cholesterol; physical activity; fruit and vegetable consumption) were assessed at 3 and 12 months. We examined group and time effects using mixed models analyses with the baseline values as covariates. The secondary outcomes were plasma lipid levels (total cholesterol, low-density lipoprotein cholesterol, HDL cholesterol and triglycerides); glucose level; blood pressure; smoking status; waist circumference; body mass index; and the use of blood pressure, lipid-lowering and smoking cessation medications.Results:
We found no effect of the intervention on the ratio of total cholesterol to HDL cholesterol. However, participants in the intervention group reported consuming more fruit and vegetables (1.2 servings per day more after 3 mo and 0.8 servings at 12 mo; p < 0.001). There was a significant group by time interaction for physical activity (p = 0.03). At 3 months, those in the intervention group reported 65.8 more minutes of physical activity per week (95% confidence interval [CI] 47.0–84.7 min). At 12 months, participants in the intervention group reported 23.9 more minutes each week (95% CI 3.9–44.0 min).Interpretation:
A health educator–led heart-health intervention did not improve the ratio of total cholesterol to HDL cholesterol but did increase reported physical activity and fruit and vegetable consumption among family members of patients with CAD. Hospitalization of a spouse, sibling or parent is an opportunity to improve cardiovascular health among other family members. Trial registration: clinicaltrials.gov, no .People with a family history of coronary artery disease (CAD) among their first-degree relatives have an increased risk of vascular events. NCT005525911–5 This risk is greater if more than 1 relative has heart disease, or if the onset of disease in relatives occurred before age 55.1–3,5 A concordance of coronary risk factors between patients with heart disease and their spouses has also been reported.6–10 Although genetic factors are important, familial aggregation of coronary risk factors also plays a role.9,11,12 Guidelines recommend screening individuals with a positive family history,13–15 but screening rates are low (< 15%), and interventions are rarely initiated.16,17 Family members of patients with heart disease may benefit from focused interventions to improve cardiovascular health. Counselling that address physical inactivity and dietary behaviours is central to these interventions; clinical management of risk factors such as tobacco addiction, dyslipidemia, hypertension and dysglycemia are also important. We developed and evaluated a year-long family-based heart-health intervention for the siblings, offspring and spouses of patients admitted to hospital with an acute coronary event. 相似文献995.
Aclees sp. cf. foveatus Voss is a new and exotic pest recently reported as responsible for severe damages to Italian fig orchards and nurseries. Investigating its mating behavioral sequence could help to unravel mate assessment and choice dynamics of this pest, adding useful information to build-up behavior-based control strategies. In this study, we observed A. sp. cf. foveatus mating behavior under field conditions. The mating behavior is divided into precopulatory, copulatory and postcopulatory phases. Simultaneous antennal tapping and rostral rubbing acts performed by the male on female’s body raises male’s chances to copulate, while males that performed only antennal tapping on the partner’s body did not achieved mating success. Copulation attempt phase lasted 37.80?±?7.65 s. Copulation lasted 1116.00?±?229.73 s and was followed by a motionless postcopulatory phase (8.40?±?1.21 s). Same-sex sexual interactions were observed among A. sp. cf. foveatus males. Male-male sexual interactions lasted about 140.17?±?19.45 s and were composed of antennal tapping and rostral rubbing followed by one or more mounting attempts. Further research is ongoing to investigate the exact nature of male- and female-borne olfactory and tactile cues routing mate recognition in A. sp. cf. foveatus. 相似文献
996.
Firooznia F Gude C Chan K Tan J Fink CA Savage P Beil ME Bruseo CW Trapani AJ Jeng AY 《Bioorganic & medicinal chemistry letters》2002,12(21):3059-3062
Directed screening of metalloprotease inhibitors identified CGS 30084 (1) as a potent inhibitor of endothelin-converting enzyme-1 (ECE-1) in vitro (IC(50)=77 nM). Herein we report the syntheses and biological activities of analogues containing modified biphenyl moieties, bearing heterocyclic proximal rings. Compound 20, the thioacetate ethyl ester prodrug derivative of compound 19a, was found to be an orally active and potent inhibitor of ECE-1 activity in rats. 相似文献
997.
Ghelardi E Celandroni F Salvetti S Barsotti C Baggiani A Senesi S 《FEMS microbiology letters》2002,208(1):129-134
The epidemiology of Bacillus cereus strains responsible for food poisoning is scantly known, mostly because the genotypic and toxigenic properties of the B. cereus strains isolated during food-poisoning outbreaks have been never catalogued. The occurrence of two simultaneous food-poisoning outbreaks gave us the opportunity to wonder whether (i) the identity of individual strains isolated from clinical, environmental, and food samples could be established by random amplified polymorphic DNA (RAPD)-PCR and multiplex RAPD-PCR, and (ii) the toxigenic potential of the isolates could be determined by testing their ability to secrete hemolysin BL, phosphatidylcholine-specific phospholipase C, and cereulide, as well as by determining the presence of the genes encoding enterotoxins NHE, T, and FM/S, cytotoxin K, sphingomyelinase, and phosphatidylinositol-specific phospholipase C. This is the first report demonstrating that the combination of several phenotypic and genotypic traits provides a powerful tool for tracing the source of infection of toxigenic B. cereus strains relevant for epidemiological survey. 相似文献
998.
The rhdA gene of Azotobacter vinelandii codes for RhdA, a rhodanese-domain protein with an active-site loop structure which has not currently been found in proteins of the rhodanese-homology superfamily. Considering the lack of information on the functional role of the ubiquitous rhodaneses, in the present study we examined the in vivo functions of RhdA by using an A. vinelandii mutant strain (MV474), in which the rhdA gene was disrupted by deletion. Preliminary phenotypic characterization of the rhdA mutant suggested that RhdA could exert protection over Fe-S enzymes, which are easy targets for oxidative damage. To highlight the role of RhdA in preserving sensitive Fe-S clusters, in the present study we analysed the defects of the rhdA-null strain by exploiting growth conditions which resulted in enhancing the catalytic deficiency of enzymes with vulnerable Fe-S clusters. We found that a lack of RhdA impaired A. vinelandii growth in the presence of gluconate, a carbon source that activates the Entner-Doudoroff pathway in which the first enzyme, 6-phosphogluconate dehydratase, employs a 4Fe-4S cluster as an active-site catalyst. By combining proteomics, enzymatic profiles and model systems to generate oxidative stress, evidence is provided that to rescue the effects of a lack of RhdA, A. vinelandii needed to activate defensive activities against oxidative damage. The possible functionality of RhdA as a redox switch which helps A. vinelandii in maintaining the cellular redox balance was investigated by using an in vitro model system that demonstrated reversible chemical modifications in the highly reactive RhdA Cys(230) thiol. 相似文献
999.
We evaluated the i-peptides occurrence frequency in the protein sequences belonging to the two datasets which include proteins with a sequence similarity lower than 25% and 40%, respectively. We worked out a new structural class prediction algorithm using the most frequent i-peptides (with i=2, 3, 4), which characterize the four structural classes. Using the tri-peptides, much more able to gain structural information from sequences compared to the di-peptides, the best results were obtained. Compared to the other methods, similarly founded on peptide occurrence frequencies, our method achieves the best prediction accuracy. We compared it also with methods founded on more sophisticated computational approaches. 相似文献
1000.
Elizabeth Bent Angelo Loffredo Jiue-in Yang Michael V. McKenry Jörn Ole Becker & James Borneman 《FEMS microbiology ecology》2009,68(2):192-200
Replant diseases often occur when pome and stone fruits are grown in soil that had previously been planted with the same or similar plant species. They typically lead to reductions in plant growth, crop yield and production duration. In this project, greenhouse assays were used to identify a peach orchard soil that caused replant disease symptoms. Biocidal treatments of this soil led to growth increases of Nemaguard peach seedlings. In addition, plants grown in as little as 1% of the replant soil exhibited reduced plant growth. These results suggest that the disease etiology has a biological component. Analysis of roots from plants exhibiting various levels of replant disease symptoms showed little difference in the amounts of PCR-amplified bacterial or fungal rRNA genes. However, analysis using a stramenopile-selective PCR assay showed that rRNA genes from this taxon were generally more abundant in plants with the smallest top weights. Nucleotide sequence analysis of these genes identified several phylotypes belonging to Bacillariophyta , Chrysophyceae , Eustigmatophyceae , Labyrinthulida , Oomycetes , Phaeophyceae and Synurophyceae . Sequence-selective quantitative PCR assays targeting four of the most abundant phylotypes showed that both diatoms ( Sellaphora spp.) and an oomycete ( Pythium ultimum ) were negatively associated with plant top weights. 相似文献