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101.
Glycolysis is for some cells, such as erythrocytes, neutrophil granulocytes and many cancer cells, the only or most important source of energy (ATP) production. Based on previous studies we developed an isotachophoretic (ITP) method which allows, in principle, the simultaneous determination of all metabolites of glycolysis. Since glucose metabolites are small anions, mobility of some of them may overlap in isotachophoresis and, therefore, partial mixed zones are generated. By variation of the leading/terminating system, however, it is possible to separate the compounds of interest. In this communication, we describe a method for analysis of glucose metabolites in erythrocytes from healthy donors during storage in blood bags, and from patients with thalassemia, with special respect to intracellular 2,3 bisphosphoglycerate, lactate and ATP/ADP. The well known characteristic changes of glycolysis in erythrocytes during blood storage and in erythrocytes from thalassemia patients, which are often analysed by separate enzymatic assays, could be confirmed with this isotachophoretic procedure. The method is currently adapted for analysis of glycolysis in neutrophil granulocytes and cancer cells which requires some modifications of sample preparation and performance of the isotachophoretic analysis.  相似文献   
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Coronaviruses (CoVs) are important human and animal pathogens that induce fatal respiratory, gastrointestinal and neurological disease. The outbreak of the severe acute respiratory syndrome (SARS) in 2002/2003 has demonstrated human vulnerability to (Coronavirus) CoV epidemics. Neither vaccines nor therapeutics are available against human and animal CoVs. Knowledge of host cell proteins that take part in pivotal virus-host interactions could define broad-spectrum antiviral targets. In this study, we used a systems biology approach employing a genome-wide yeast-two hybrid interaction screen to identify immunopilins (PPIA, PPIB, PPIH, PPIG, FKBP1A, FKBP1B) as interaction partners of the CoV non-structural protein 1 (Nsp1). These molecules modulate the Calcineurin/NFAT pathway that plays an important role in immune cell activation. Overexpression of NSP1 and infection with live SARS-CoV strongly increased signalling through the Calcineurin/NFAT pathway and enhanced the induction of interleukin 2, compatible with late-stage immunopathogenicity and long-term cytokine dysregulation as observed in severe SARS cases. Conversely, inhibition of cyclophilins by cyclosporine A (CspA) blocked the replication of CoVs of all genera, including SARS-CoV, human CoV-229E and -NL-63, feline CoV, as well as avian infectious bronchitis virus. Non-immunosuppressive derivatives of CspA might serve as broad-range CoV inhibitors applicable against emerging CoVs as well as ubiquitous pathogens of humans and livestock.  相似文献   
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Peripheral arterial disease (PAD) is an atherosclerotic disease. Evidence suggests that atherosclerosis is an inflammatory condition and long chain n-3 fatty acids, found in oily fish and fish oils, have been shown to reduce inflammation. Genetic and lifestyle factors such as body mass index (BMI) also influence inflammation. In this study we have examined the effect of fish oil in patients with claudication secondary to PAD. Fish oil supplementation, providing 1g EPA and 0.7 g DHA per day for 12 weeks, increased walking distance on a treadmill set at 3.2 km/h with a 7% incline. Walking distance to first pain increased from 76.2+/-8.5 m before fish oil to 140.6+/-25.5 m after fish oil (mean+/-SEM, p=0.004) and total distance walked increased from 160.0+/-21.5 m before fish oil to 242.1+/-34.5 m after fish oil (p=0.002). Fish oil supplementation also improved ankle brachial pressure index (ABPI) from 0.599+/-0.017 before fish oil to 0.776+/-0.030 after fish oil (p<0.001). The increase in walking distance was dependent on both BMI and genotype for single nucleotide polymorphisms in the genes encoding the pro-inflammatory cytokines tumour necrosis factor-alpha and interleukin (IL)-1beta and the anti-inflammatory cytokine IL-10 (detected using amplification refractory mutation system polymerase chain reaction). Neither BMI nor any of the genotypes examined affected the ability of fish oil to increase ABPI. The mechanisms by which fish oil affects walking distance and ABPI do not appear to be the same.  相似文献   
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Plasmid pGNB1 was isolated from bacteria residing in the activated sludge compartment of a wastewater treatment plant by using a transformation-based approach. This 60-kb plasmid confers resistance to the triphenylmethane dye crystal violet and enables its host bacterium to decolorize crystal violet. Partial sequencing of pGNB1 revealed that its backbone is very similar to that of previously sequenced IncP-1beta plasmids. The two accessory regions of the plasmid, one located downstream of the replication initiation gene trfA and the other located between the conjugative transfer modules Tra and Trb, were completely sequenced. Accessory region L1 contains a transposon related to Tn5501 and a gene encoding a Cupin 2 conserved barrel protein with an unknown function. The triphenylmethane reductase gene tmr and a truncated dihydrolipoamide dehydrogenase gene that is flanked by IS1071 and another putative insertion element were identified in accessory region L2. Subcloning of the pGNB1 tmr gene demonstrated that this gene is responsible for the observed crystal violet resistance phenotype and mediates decolorization of the triphenylmethane dyes crystal violet, malachite green, and basic fuchsin. Plasmid pGNB1 and the associated phenotype are transferable to the alpha-proteobacterium Sinorhizobium meliloti and the gamma-proteobacterium Escherichia coli. This is the first report of a promiscuous IncP-1beta plasmid isolated from the bacterial community from a wastewater treatment plant that harbors a triphenylmethane reductase gene. The pGNB1-encoded enzyme activity is discussed with respect to bioremediation of sewage polluted with triphenylmethane dyes.  相似文献   
108.
Molecular sensing in the lingual mucosa and in the gastro-intestinal tract play a role in the detection of ingested harmful drugs and toxins. Therefore, genetic polymorphisms affecting the capability of initiating these responses may be critical for the subsequent efficiency of avoiding and/or eliminating possible threats to the organism. By using a tagging approach in the region of Taste Receptor 2R38 (TAS2R38) gene, we investigated all the common genetic variation of this gene region in relation to colorectal cancer risk with a case-control study in a German population (709 controls and 602 cases) and in a Czech population (623 controls and 601 cases). We found that there were no significant associations between individual SNPs of the TAS2R38 gene and colorectal cancer in the Czech or in the German population, nor in the joint analysis. However, when we analyzed the diplotypes and the phenotypes we found that the non-taster group had an increased risk of colorectal cancer in comparison to the taster group. This association was borderline significant in the Czech population, (OR = 1.28, 95% CI 0.99–1.67; Pvalue = 0.058) and statistically significant in the German population (OR = 1.36, 95% CI 1.06–1.75; Pvalue = 0.016) and in the joint analysis (OR = 1.34, 95% CI 1.12–1.61; Pvalue = 0.001). In conclusion, we found a suggestive association between the human bitter tasting phenotype and the risk of CRC in two different populations of Caucasian origin.  相似文献   
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Background

Effective provider-parent communication can improve childhood vaccination uptake and strengthen immunisation services in low- and middle-income countries (LMICs). Building capacity to improve communication strategies has been neglected. Rigorous research exists but is not readily found or applicable to LMICs, making it difficult for policy makers to use it to inform vaccination policies and practice. The aim of this project is to build research knowledge and capacity to use evidence-based strategies for improving communication about childhood vaccinations with parents and communities in LMICs.

Methods and design

This project is a mixed methods study with six sub-studies. In sub-study one, we will develop a systematic map of provider-parent communication interventions for childhood vaccinations by screening and extracting data from relevant literature. This map will inform sub-study two, in which we will develop a taxonomy of interventions to improve provider-parent communication around childhood vaccination. In sub-study three, the taxonomy will be populated with trial citations to create an evidence map, which will also identify how evidence is linked to communication barriers regarding vaccination. In the project's fourth sub-study, we will present the interventions map, taxonomy, and evidence map to international stakeholders to identify high-priority topics for systematic reviews of interventions to improve parent-provider communication for childhood vaccination. We will produce systematic reviews of the effects of high-priority interventions in the fifth sub-study. In the sixth and final sub-study of the project, evidence from the systematic reviews will be translated into accessible formats and messages for dissemination to LMICs.

Discussion

This project combines evidence mapping, conceptual and taxonomy development, priority setting, systematic reviews, and knowledge transfer. It will build and share concepts, terms, evidence, and resources to aid the development of communication strategies for effective vaccination programmes in LMICs.  相似文献   
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