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1.
Journal of Ethology - By gathering data on people during their ordinary daily activities, we tested if looking at, but not manipulating, smartphones led to a mimicry response in the observer....  相似文献   
2.
We evaluated the levels of15(S)-hydroxyeicosatetraenoic acid [15(S)-HETE] and the expression of15-lipoxygenase (15-LO) mRNA in induced sputum obtained from 10 controland 15 chronic bronchitis subjects. 15(S)-HETE was evaluated by reversephase high-performance liquid chromatography separationfollowed by specific RIA. 15-LO mRNA expression was determined byprimed in situ labeling. The levels of both soluble and cell-associated 15(S)-HETE resulted significantly higher in chronic bronchitis than incontrol subjects. The percentage of cells expressing 15-LO mRNA wassignificantly higher in chronic bronchitis than in control subjects(P < 0.01). Double staining for specific cell typemarkers and 15-LO mRNA showed macrophages and neutrophils positive for 15-LO, whereas similar staining of peripheral blood neutrophils did notshow evidence for 15-LO expression, suggesting that expression of 15-LOin neutrophils takes place on migration into the airways. Because15(S)-HETE inversely correlated with the percentage of neutrophils insputum of chronic bronchitis subjects, we studied the effect of15(S)-HETE on leukotriene B4 (LTB4) productionin vitro and evaluated the concentration of LTB4 in inducedsputum and the contribution of LTB4 to the chemotacticactivity of induced sputum samples ex vivo. The results obtainedindicate that macrophages and neutrophils present within the airways ofchronic bronchitis subjects express 15-LO mRNA; increased basal levelsof 15(S)-HETE may contribute to modulate, through the inhibition of5-lipoxygenase metabolites production, neutrophil infiltration andairway inflammation associated with chronic bronchitis.

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3.
We quantified TGF-β1 and acetylcholine (ACh) concentrations in induced sputum supernatants (ISSs) from 18 healthy controls (HC), 22 healthy smokers (HS) and 21 COPDs. ISSs from HC, HS and COPD as well as rhTGF-β1 were also tested in neutrophil adhesion and in mAChR2, mAChR3 and ChAT expression experiments in human bronchial epithelial cells (16-HBE). Finally, we evaluated the effects of Olodaterol (a novel inhaled β(2)-adrenoceptor agonist) and Tiotropium Spiriva?, alone or in combination, on neutrophil adhesion and mAChRs and ChAT expression in stimulated 16-HBE. The results showed that 1) TGF-β1 and ACh concentrations are increased in ISSs from COPD in comparison to HC and HS, and TGF-β1 in HS is higher than in HC; 2) ISSs from COPD and HS caused increased neutrophil adhesion to 16-HBE when compared to ISSs from HC. The effect of ISSs from COPD was significantly reduced by TGF-β1 depletion or by the pretreatment with Olodaterol or Tiotropium alone or in combination, while the effect of ISSs from HS was significantly reduced by the pretreatment with Olodaterol alone; 3) mAChR2, mAChR3 and ChAT expression was increased in 16-HBE stimulated with ISSs from COPD and TGF-β1 depletion significantly reduced this effect on mAChR3 and ChAT expression; 4) rhTGF-β1 increased mAChR2, mAChR3 and ChAT expression in 16-HBE; 5) Olodaterol did not affect the expression of mAChRs and ChAT in 16-HBE. Our findings support the use of β? long-acting and anticholinergic drugs to control the bronchoconstriction and TGF-β1-mediated neutrophilic inflammation in COPD.  相似文献   
4.
Ballota L. comprises several relevant species largely used for their excellent therapeutic properties. Ballota hispanica (L.) Benth. is widely used in herbal medicine, and it is sold in herbalist shops for its sedative and antispasmodic properties. Considering its traditional medicinal use and the lack of scientific studies on the volatile components of this species as well as on its biological activities, in this study the chemical composition of the essential oil from aerial parts of B. hispanica, collected in Sicily, was evaluated by gas chromatography and gas chromatography–mass spectrometry. α-Elemol was the most abundant component of the oil (10.9%), followed by α-ylangene (8.5%), γ-dodecalactone (5.1%), and manoyl oxide (4.8%). A comparison was made of the composition of the different Ballota taxa studied so far showing a peculiar profile of B. hispanica. Futhermore, the antimicrobial and the free radical scavenging activities of the oil were determined.  相似文献   
5.
The chemical composition of the essential oil isolated from the aerial parts of Pulicaria sicula (L.) Moris was characterized by GC‐FID and GC/MS analyses. The oil was particularly rich in oxygenated terpenoids. Among the oxygenated monoterpenes (content of 44.5%), the most abundant were borneol (23.7%), bornyl acetate (6.5%), and isothymol isobutyrate (6.2%). Caryophyllene oxide (10.2%), caryophylladienol I (4.3%), and caryophylla‐3,8(13)‐dien‐5β‐ol (4.4%) were identified as the main constituents among the oxygenated sesquiterpenes. Furthermore, a complete literature review on the composition of the essential oils of all the Pulicaria taxa studied so far was performed and a principal component analysis (PCA) was carried out.  相似文献   
6.
A new method is described for the isolation of subunits of the light-harvesting complex from Rhodospirillum rubrum (wild type and the G-9 mutant) in yields that approach 100%. The procedure involved treating membrane vesicles with ethylenediaminetetraacetic acid-Triton X-100 to remove components other than the light-harvesting complex and reaction center. In the preparation from wild-type cells, a benzene extraction was then employed to remove carotenoid and ubiquinone. The next step involved a careful addition of the detergent n-octyl beta-D-glucopyranoside, which resulted in a quantitative shift of the long-wavelength absorbance maximum from 873 to 820 nm. This latter complex was then separated from reaction centers by gel filtration on Sephadex G-100. The pigment-protein complex, now absorbing at 820 nm, contained two polypeptides of about 6-kilodalton molecular mass (referred to as alpha and beta) in a 1:1 ratio and two molecules of bacteriochlorophyll (BChl) for each alpha beta pair. This complex is much smaller in size than the original complex absorbing at 873 nm but probably is an associated form such as alpha 2 beta 2 X 4BChl or alpha 3 beta 3 X 6BChl. The 820-nm form could be completely shifted back to a form once again having a longer wavelength lambda max near 873 nm by decreasing the octyl glucoside concentration. Thus, the complex absorbing at 820 nm appears to be a subunit form of the original 873-nm complex.  相似文献   
7.
8.
The chemical composition of the essential oils isolated from the aerial parts of Anthemis pignattiorum Guarino, Raimondo & Domina and A. ismelia Lojac . and the aerial parts and flowers of Anthemis cupaniana Tod . ex Nyman , three endemic Sicilian species belonging to the section Hiorthia, was determined by GC‐FID and GC/MS analyses. (Z)‐Muurola‐4(14),5‐diene (27.3%) was recognized as the main constituent of the A. pignattiorum essential oil, together with isospathulenol (10.6%), sabinene (7.7%), and artemisyl acetate (6.8%), while in the oil obtained from the aerial parts of A. ismelia, geranyl propionate (8.8%), bornyl acetate (7.9%), β‐thujone (7.8%), neryl propionate (6.5%), and τ‐muurolol (6.5%) prevailed. α‐Pinene was the main compound of both the aerial part and flower oils of A. cupaniana (18.4 and 13.2%, resp.). Also noteworthy are the considerable amounts of artemisyl acetate (12.7%) and β‐thujone (11.8%) found in the oil from the aerial parts and those of tricosane (9.8%) and sabinene (7.6%) evidenced in the flower oil. Furthermore, an update on the main compounds identified in the essential oils of all the Anthemis taxa studied so far was presented, and cluster analyses were carried out, to compare the essential oils of these taxa.  相似文献   
9.

Background

Quinolones are potent broad-spectrum bactericidal agents increasingly employed also in resource-limited countries. Resistance to quinolones is an increasing problem, known to be strongly associated with quinolone exposure. We report on the emergence of quinolone resistance in a very remote community in the Amazon forest, where quinolones have never been used and quinolone resistance was absent in 2002.

Methods

The community exhibited a considerable level of geographical isolation, limited contact with the exterior and minimal antibiotic use (not including quinolones). In December 2009, fecal carriage of antibiotic resistant Escherichia coli was investigated in 120 of the 140 inhabitants, and in 48 animals reared in the community. All fluoroquinolone-resistant isolates were genotyped and characterized for the mechanisms of plasmid- and chromosomal-mediated quinolone resistance.

Principal Findings

Despite the characteristics of the community remained substantially unchanged during the period 2002–2009, carriage of quinolone-resistant E. coli was found to be common in 2009 both in humans (45% nalidixic acid, 14% ciprofloxacin) and animals (54% nalidixic acid, 23% ciprofloxacin). Ciprofloxacin-resistant isolates of human and animal origin showed multidrug resistance phenotypes, a high level of genetic heterogeneity, and a combination of GyrA (Ser83Leu and Asp87Asn) and ParC (Ser80Ile) substitutions commonly observed in fluoroquinolone-resistant clinical isolates of E. coli.

Conclusions

Remoteness and absence of antibiotic selective pressure did not protect the community from the remarkable emergence of quinolone resistance in E. coli. Introduction of the resistant strains from antibiotic-exposed settings is the most likely source, while persistence and dissemination in the absence of quinolone exposure is likely mostly related with poor sanitation. Interventions aimed at reducing the spreading of resistant isolates (by improving sanitation and water/food safety) are urgently needed to preserve the efficacy of quinolones in resource-limited countries, as control strategies based only on antibiotic restriction policies are unlikely to succeed in those settings.  相似文献   
10.
In the present study, the chemical composition of the essential oils from aerial parts of Centaurea grinensis Reuter (K) collected at ?uta Lova, near Senj (Croatia), and aerial parts (L1) and flowers (L2) of C. apiculata Ledeb. collected near Rebro village, near Breznik town, Znepole Region (Bulgaria), both belonging to subgenus Lopholoma (Cass.) Dobrocz, was evaluated by GC and GC-MS. The main components of K were 4-vinyl guaiacol (21.5%), hexadecanoic acid (16.2%), acetophenone (12.5%). Caryophyllene oxide (15.8%) together with sphathulenol (14.5%) and humulene epoxide II (9.4%) were recognized as the main constituent of both the aerial part (L1) and flowers (L2) of C. apiculata. Furthermore, a complete review on the composition of the essential oils of all the Centaurea taxa belonging to subgenus Lopholoma studied so far has been inserted and cluster analysis (PCA) was carried out.  相似文献   
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