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121.
A novel series of 1,5-diarylpyrrol-3-sulfur derivatives (1012) was synthesized and characterized by NMR and mass spectroscopy and x-ray diffraction. The biological activity of these compounds was evaluated in in vitro and in vivo tests to assess their COX-2 inhibitory activity along with anti-inflammatory and antinociceptive effect.Results showed that the bioisosteric transformation of previously reported alkoxyethyl ethers (9a-c) into the corresponding alkyl thioethers (10a-c) still leads to selective and active compounds being the COX-2 inhibitory activity for most of them in the low nanomolar range. The oxidation products of 10a,b were also investigated and both couple of sulfoxides (11a,b) and sulfones (12a,b) showed an appreciable COX-2 inhibitory activity. Molecular modeling studies were performed to investigate the binding mode of the representative compounds 10b, 11b, and 12b into COX-2 enzyme and to explore the potential site of metabolism of 10a and 10b due to the different in vivo efficacy. Among the developed compounds, compound 10b showed a significant in vivo anti-inflammatory and antinociceptive activity paving the way to develop novel anti-inflammatory drugs.  相似文献   
122.
Bottom‐up evolutionary approaches, including geographically explicit population genomic analyses, have the power to reveal the mechanistic basis of adaptation. Here, we conduct a population genomic analysis in the model legume, Medicago truncatula, to characterize population genetic structure and identify symbiosis‐related genes showing evidence of spatially variable selection. Using RAD‐seq, we generated over 26,000 SNPs from 191 accessions from within three regions of the native range in Europe. Results from STRUCTURE analysis identify five distinct genetic clusters with divisions that separate east and west regions in the Mediterranean basin. Much of the genetic variation is maintained within sampling sites, and there is evidence for isolation by distance. Extensive linkage disequilibrium was identified, particularly within populations. We conducted genetic outlier analysis with FST‐based genome scans and a Bayesian modeling approach (PCAdapt). There were 70 core outlier loci shared between these distinct methods with one clear candidate symbiosis related gene, DMI1. This work sets that stage for functional experiments to determine the important phenotypes that selection has acted upon and complementary efforts in rhizobium populations.  相似文献   
123.

Objectives

This study aims to compare breast cancer screening (BCS) and cervical cancer screening (CCS) practices of French women born to French parents with those of immigrants and nationals born to immigrants, taking their socioeconomic status into account.

Methods

The study is based on data collected in 2010 in the Paris metropolitan area among a representative sample of 3000 French-speaking adults. For women with no history of breast or cervical cancer, multivariate logistic regressions and structural equation models were used to investigate the factors associated with never having undergone BCS or CCS.

Results

We confirmed the existence of a strong gradient, with respect to migration origin, for delaying or never having undergone BCS or CCS. Thus, being a foreign immigrant or being French of immigrant parentage were risk factors for delayed and no lifetime screening. Interestingly, we found that this gradient persisted (at least partially) after adjusting for the women’s socioeconomic characteristics. Only the level of income seemed to play a mediating role, but only partially. We observed differences between BCS and CCS which suggest that organized CCS could be effective in reducing socioeconomic and/or ethnic inequities.

Conclusion

Socioeconomic status partially explained the screening nonparticipation on the part of French women of immigrant origin and foreign immigrants. This was more so the case with CCS than with BCS, which suggests that organized prevention programs might reduce social inequalities.  相似文献   
124.
The salt overly sensitive (SOS) pathway is critical for plant salt stress tolerance and has a key role in regulating ion transport under salt stress. To further investigate salt tolerance factors regulated by the SOS pathway, we expressed an N-terminal fusion of the improved tandem affinity purification tag to SOS2 (NTAP-SOS2) in sos2-2 mutant plants. Expression of NTAP-SOS2 rescued the salt tolerance defect of sos2-2 plants, indicating that the fusion protein was functional in vivo. Tandem affinity purification of NTAP-SOS2-containing protein complexes and subsequent liquid chromatography-tandem mass spectrometry analysis indicated that subunits A, B, C, E, and G of the peripheral cytoplasmic domain of the vacuolar H+-ATPase (V-ATPase) were present in a SOS2-containing protein complex. Parallel purification of samples from control and salt-stressed NTAP-SOS2/sos2-2 plants demonstrated that each of these V-ATPase subunits was more abundant in NTAP-SOS2 complexes isolated from salt-stressed plants, suggesting that the interaction may be enhanced by salt stress. Yeast two-hybrid analysis showed that SOS2 interacted directly with V-ATPase regulatory subunits B1 and B2. The importance of the SOS2 interaction with the V-ATPase was shown at the cellular level by reduced H+ transport activity of tonoplast vesicles isolated from sos2-2 cells relative to vesicles from wild-type cells. In addition, seedlings of the det3 mutant, which has reduced V-ATPase activity, were found to be severely salt sensitive. Our results suggest that regulation of V-ATPase activity is an additional key function of SOS2 in coordinating changes in ion transport during salt stress and in promoting salt tolerance.  相似文献   
125.

Background  

A polarized light scattering technique was used to monitor the performance of a continuously operated foam fractionation process. The S 11 and S 12 parameters, elements of the light scattering matrix, combined together (S 11 +S 12) have been correlated with the bubble size and liquid content for the case of a freely draining foam. The performance of a foam fractionation column is known to have a strong dependence on the bubble size distribution and liquid hold up in foam. In this study the enrichment is used as a metric, representative of foam properties and column performance, and correlated to the S 11 +S 12 parameter.  相似文献   
126.
127.
Platelet-activating factor is a phospholipid mediator that exhibits a wide variety of physiological and pathophysiological effects, including induction of inflammatory response, chemotaxis and cellular differentiation. Trypanosoma cruzi, the etiological agent of Chagas' disease, is transmitted by triatomine insects and while in the triatomine midgut the parasite differentiates from a non-infective epimastigote stage into the pathogenic trypomastigote metacyclic form. We have previously demonstrated that platelet activating factor triggers in vitro cell differentiation of T. cruzi. Here we show a platelet activating factor-like activity isolated from lipid extract of T. cruzi epimastigotes incubated in the presence of [14C]acetate. Trypanosoma cruzi-platelet activating factor-like lipid induced the aggregation of rabbit platelets, which was prevented by platelet activating factor-acetylhydrolase. Mouse macrophage infection by T. cruzi was stimulated when epimastigotes were kept for 5 days in the presence of T. cruzi-platelet activating factor, before interacting with the macrophages. The differentiation of epimastigotes into metacyclic trypomastigotes was also triggered by T. cruzi-platelet activating factor. These effects were abrogated by a platelet activating factor antagonist, WEB 2086. Polyclonal antibody raised against mouse platelet activating factor receptor showed labelling for T. cruzi epimastigotes using immunoblotting and immunofluorescence assays. These data suggest that T. cruzi contain the components of an autocrine platelet activating factor-like ligand-receptor system that modulates cell differentiation towards the infectious stage.  相似文献   
128.
It is of interest to evaluate the prevalence of systemic disorders in patients undergoing minor oral surgeries at a dental hospital. This will help to take necessary precautions prior to oral surgeries. We used the digital case records of 1288 patients who underwent minor oral surgeries in a hospital. Demographic details and systemic diseases of the patients were recorded from digital case records. Data shows that 103 patients (7.9%) of the total number of patients undergoing minor oral surgeries had systemic diseases with 3.8% of patients diagnosed with diabetes. Statistically significant associations were found between type of minor oral surgery and the type of systemic disease (p<0.001); age of patients and type of minor oral surgery (p<0.001); age and type of systemic diseases (p<0.001) and gender of patient and type of minor oral surgery (p = 0.005). Thus, data shows the prevalence of systemic diseases in patients undergoing minor oral surgeries was 7.9%.  相似文献   
129.
Escherichia coli has been recognized as the principal indicator of fecal contamination of water. Indeed, E. coli is the only species in the coliform group found in relationship with gastrointestinal tract of human and warm‐blooded animals and subsequently excreted in large numbers in the human feces. To obtain a complete picture of water quality and therefore, a better protection of public health, different techniques for water analysis have been proposed. In this article, we describe an alternative method that uses SYBR green real time‐polymerase chain reaction (RT‐PCR) technology to identify and quantify all E. coli biotypes in a group of wastewater samples collected from a wastewater depurator located in South of Italy. This new RT‐PCR protocol is accurate in measuring the concentration of chromosomal E. coli DNA using the amplification of three new specific fragments of the following bacteria genes: CadC, HNS, and Allan whose sequence is specific for E. coli family and conserved in all E. coli subtypes. This method allowed us to detect the presence of all E. coli biotypes directly in wastewater samples and estimated the correspondence between colony forming units and bacterial DNA concentrations. The availability of a rapid and sensitive method may be useful to monitor the persistence of E. coli in water, to evaluate the efficiency of wastewater purification treatments and the possible recycle for agricultural use. Furthermore, the development of a simple and routine method to monitor water quality with RT‐PCR analysis can encourage the testing of a higher number of samples. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 28: 1106–1113, 2012  相似文献   
130.
In this study we describe the sociodemographic characteristics of people participating in a clinical trial on the safety and immunogenicity of a H5N1 influenza vaccine and we identify the main motivations for joining it.  相似文献   
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