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21.
Diagnostic methods for parasite infections still highly depend on the identification of the parasites by direct methods such as microscopic examination of blood, stool and tissue biopsies. Serodiagnosis is often carried out to complement the direct methods; however, few synthetic antigens with sufficient sensitivity and specificity are available. Here we evaluated a glycan microarray approach to select for synthetic glycan antigens that could be used for serodiagnosis of parasitic infections. Using a glycan array containing over 250 different glycan antigens, we identified GalNAcβ1–4(Fucα1–3)GlcNAc-R (LDNF) as a glycan antigen that is recognized by antibodies from Trichinella-infected individuals. We synthesized a neoglycoconjugate, consisting of five LDNF molecules covalently coupled to bovine serum albumin (BSA), and used this neoglycoconjugate as an antigen to develop a highly sensitive total-Ig ELISA for serological screening of trichinellosis. The results indicate that glycan microarrays constitute a promising technology for fast and specific identification of parasite glycan antigens to improve serodiagnosis of different parasitic infections, either using an ELISA format, or parasite-specific glycan arrays.  相似文献   
22.
β-Amyloid (Aβ), a peptide generated from the amyloid precursor protein, is widely believed to underlie the pathophysiology of Alzheimer disease (AD). Emerging evidences suggest that soluble Aβ oligomers adversely affect synaptic function, leading to cognitive failure associated with AD. The Aβ-induced synaptic dysfunction has been attributed to the synaptic removal of α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors (AMPARs). However, the molecular mechanisms underlying the loss of AMPAR induced by Aβ at synapses are largely unknown. In this study we have examined the effect of Aβ oligomers on phosphorylated GluA1 at serine 845, a residue that plays an essential role in the trafficking of AMPARs toward extrasynaptic sites and the subsequent delivery to synapses during synaptic plasticity events. We found that Aβ oligomers reduce basal levels of Ser-845 phosphorylation and surface expression of AMPARs affecting AMPAR subunit composition. Aβ-induced GluA1 dephosphorylation and reduced receptor surface levels are mediated by an increase in calcium influx into neurons through ionotropic glutamate receptors and activation of the calcium-dependent phosphatase calcineurin. Moreover, Aβ oligomers block the extrasynaptic delivery of AMPARs induced by chemical synaptic potentiation. In addition, reduced levels of total and phosphorylated GluA1 are associated with initial spatial memory deficits in a transgenic mouse model of AD. These findings indicate that Aβ oligomers could act as a synaptic depressor affecting the mechanisms involved in the targeting of AMPARs to the synapses during early stages of the disease.  相似文献   
23.

Background

Currently, there is an intensive debate about the regulation of the use of electronic cigarettes (e-cigarettes) in indoor places. The aim of this study was to assess the attitudes toward e-cigarette use in indoor workplaces and selected public and private venues among the general population in Barcelona (Spain) in 2013–2014.

Methods

This is a cross-sectional study of a representative sample of the population of Barcelona (n = 736). The field work was conducted between May 2013 and February 2014. We computed the prevalence and the adjusted odds ratios (OR) derived from multivariable logistic regression models.

Results

The awareness of e-cigarettes was 82.3%. Forty five percent of respondents did not agree with the use of e-cigarettes in public places and 52.3% in workplaces. The proportion of disapproval of the use of e-cigarettes in indoor places was higher at 71.5% for schools and 65.8% for hospitals and health care centers; while the prevalence of disapproval of e-cigarette use in homes and cars was lower (18.0% and 32.5%, respectively). Respondents who disagreed on the use of e-cigarettes in indoor workplaces were more likely to be older (OR = 1.64 and 1.97 for groups 45–64 and ≧65 years old, respectively), those with a high educational level (OR = 1.60), and never and former smokers (OR = 2.34 and 2.16, respectively). Increased scores in the Fagerström test for cigarette dependence were also related to increased support for their use.

Conclusions

Based on this population based study, half of the general population of Barcelona does not support the use of e-cigarettes in indoor workplaces and public places, with the percentage reaching 65% for use in schools, hospitals and health care centers. Consequently, there is good societal support in Spain for the politicians and legislators to promote policies restricting e-cigarettes use in workplaces and public places, including hospitality venues.  相似文献   
24.
CD6 is a type I membrane glycoprotein expressed on thymocytes, mature T and B1a lymphocytes, and CNS cells. CD6 binds to activated leukocyte cell adhesion molecule (CD166), and is considered as a costimulatory molecule involved in lymphocyte activation and thymocyte development. Accordingly, CD6 partially associates with the TCR/CD3 complex and colocalizes with it at the center of the mature immunological synapse (IS) on T lymphocytes. However, the signaling pathway used by CD6 is still mostly unknown. The yeast two-hybrid system has allowed us the identification of syntenin-1 as an interacting protein with the cytoplasmic tail of CD6. Syntenin-1 is a PDZ (postsynaptic density protein-95, postsynaptic discs large, and zona occludens-1) domain-containing protein, which functions as an adaptor protein able to bind cytoskeletal proteins and signal transduction effectors. Mutational analyses showed that certain amino acids of the most C-terminal sequence of CD6 (-YDDISAA) and the two postsynaptic density protein-95, postsynaptic discs large, and zona occludens-1 domains of syntenin-1 are relevant to the interaction. Further confirmation of the CD6-syntenin-1 interaction was obtained from pull-down and co-immunoprecipitation assays in mammalian cells. Image analyses also showed that syntenin-1 accumulates at CD6 caps and at the IS. Therefore, we propose that syntenin-1 may function as a scaffolding protein coupling CD6 and most likely other lymphocyte receptors to cytoskeleton and/or signaling effectors during IS maturation.  相似文献   
25.
26.

Background

Wild food plants (WFP) have always been consumed by humans, first as the main basis of their food and, since the origins of agriculture, as ingredients of normal diets or as an alternative during situations of scarcity. In contemporary industrialized societies their use is for the most part being abandoned, but they may still play an important role. With the purpose of advancing in the ethnobotanical knowledge of one region of the Catalan Pyrenees, the present study reports the findings of a research project conducted in the Ripollès district (Catalonia, Iberian Peninsula), concerning ethnobotanical knowledge and use of wild and semi-wild vascular plants as foods, along with minor crops.

Methods

From August 2004 to July 2014, we performed 104 interviews (93 of which yielded data on food plants) with 163 informants, using the method of semi-structured ethnobotanical interview. We identified the plants quoted and kept herbarium vouchers.

Results

We detected 967 use reports for 80 wild or naturalized taxa, which are or have been consumed in the Ripollès district, the most cited being Taraxacum dissectum, Cynara cardunculus and Origanum vulgare. Certain frequently reported species such as Molopospermum peloponnesiacum and Taraxacum dissectum have only been rarely cited previously or indicated as food plant in very restricted geographical areas. Most cited families included Asteraceae and Lamiaceae, followed by Rosaceae and Apiaceae. Preferred consumed plant parts included leaves, followed by aerial parts, along with fruits and infructescences, while most wild food plants are eaten raw or used as condiments. Demographic factors such as age and locality of informants seem to be more relevant to wild food plant knowledge than gender. Middle-aged people and inhabitants from the Higher Freser River Valley seem to have a greater knowledge of WFP, both in relation to the number of species elicited, as well as the diversity of uses and preparations. To a lesser degree, women seem to have a slightly higher WFP knowledge than men. The consumption of these resources is still fairly alive amongst the populace, yet changes affecting younger generations–in most cases abandonment–have been reported by various participants.

Conclusion

The information provided by this kind of research permits the detection of those traditional species that could constitute the basis for the future development and management of wild edible plant resources along with minor crops. It also helps to determine the factors affecting their use, as well as the distinct target groups that such programmes could be addressed to.
  相似文献   
27.
Smoking increases the risk of many diseases and could act through changes in DNA methylation patterns. The aims of this study were to determine the association between smoking and DNA methylation throughout the genome at cytosine-phosphate-guanine (CpG) site level and genomic regions. A discovery cross-sectional epigenome-wide association study nested in the follow-up of the REGICOR cohort was designed and included 645 individuals. Blood DNA methylation was assessed using the Illumina HumanMethylation450 BeadChip. Smoking status was self-reported using a standardized questionnaire. We identified 66 differentially methylated CpG sites associated with smoking, located in 38 genes. In most of these CpG sites, we observed a trend among those quitting smoking to recover methylation levels typical of never smokers. A CpG site located in a novel smoking-associated gene (cg06394460 in LNX2) was hypomethylated in current smokers. Moreover, we validated two previously reported CpG sites (cg05886626 in THBS1, and cg24838345 in MTSS1) for their potential relation to atherosclerosis and cancer diseases, using several different approaches: CpG site methylation, gene expression, and plasma protein level determinations. Smoking was also associated with higher THBS1 gene expression but with lower levels of thrombospondin-1 in plasma. Finally, we identified differential methylation regions in 13 genes and in four non-coding RNAs. In summary, this study replicated previous findings and identified and validated a new CpG site located in LNX2 associated with smoking.  相似文献   
28.

Background

The aim of our work was to identify the genes specifically altered in pancreatic adenocarcinoma and especially those that are altered early in cancer development.

Methodology/Principal Findings

Gene copy number was systematically assessed with an ultra-high resolution CGH oligonucleotide microarray in DNA from samples of pancreatic cancer. Several new cancer-associated variations were observed. In this work we focused on one of them, involving the reg4 gene. Gene copy number gain of the reg4 gene was confirmed by qPCR in 14 cancer samples. It was also found with increased copy number in most PanIN3 samples. The relationship betweena gain in reg4 gene copy number and cancer development was investigated on the human pancreatic cancer cell line Mia-PaCa2 xenografted under the skin of nude mice. When cells were transfected with a vector allowing reg4 expression, they generated tumors almost twice larger in size. In addition, these tumors were more resistant to gemcitabine treatment than control tumors. Interestingly, weekly intraperitoneal administration of a monoclonal antibody to reg4 halved the size of tumors generated by Mia-PaCa2 cells, suggesting that the antibody interfered with a paracrine/autocrine mechanism involving reg4 and stimulating cancer progression. The addition of gemcitabine resulted in further reduction, tumors becoming 5 times smaller than control. Exposure to reg4 antibody resulted in a significant decrease in intra-tumor levels of pAkt, Bcl-xL, Bcl-2, survivin and cyclin D1.

Conclusions/Significance

It was concluded that adjuvant therapies targeting reg4 could improve the standard treatment of pancreatic cancer with gemcitabine.  相似文献   
29.
The granule-dependent exocytosis pathway is an important mechanism to induce apoptosis by CD8(+) T cells and NK cells and involves lytic molecules such as perforin. In the current study, we investigated the perforin 1 gene (PRF1) as a candidate for multiple sclerosis (MS) susceptibility in the Spanish population. We genotyped three PRF1 single nucleotide polymorphisms (rs885822, rs10999426, and rs3758562) in 420 patients with MS and 512 controls. Associations of PRF1 polymorphisms with the disease were restricted to male patients with MS, and the finding was consistently observed at the allele, genotype, and haplotype levels. Gender-associated differences were validated in an additional replication cohort comprised of 292 MS cases and 300 controls. In addition, we identified minor risk haplotypes strongly associated with male patients having primary progressive MS (PPMS). Further characterization of male patients with PPMS carrying the risk haplotypes by means of gene expression microarrays revealed overrepresentation of the cell killing gene ontology category among downregulated genes in these patients compared with male patients with PPMS carrying protective haplotypes. Moreover, PRF1 mRNA expression levels were significantly lower in patients with risk haplotypes, and changes in perforin protein expression by CD8(+) T cells mirrored those observed in gene expression. These findings suggest a gender dimorphism in the PRF1 association with MS and point to the presence of a generalized defect in the expression of genes that code for proteins involved in cell killing in a subgroup of male patients with PPMS.  相似文献   
30.
Multivariate resolution methods make up a set of mathematical tools that may be applied to the analysis and interpretation of spectroscopic data recorded when monitoring a physical or chemical process with multichannel detectors. The goal of resolution methods is the recovery of chemical and/or physical information from the experimental data. Such data include, for example, the number of intermediates present in a reaction, the rate or equilibrium constants, and the spectra for each one of those intermediates. Multivariate resolution methods have been shown to be useful for the study of biophysical and biochemical processes such as folding/unfolding of proteins or nucleic acids. The present article reviews the most frequently used resolution methods, the limitations on their use, and their latest applications in protein and nucleic acid research.  相似文献   
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