505 research outputs found

    Differences in potassium uptake in grapevine varieties: Reasons and perspectives

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    The varietal differences in potassium uptake in two grapevine cultivars (Vitis vinifera L. cvs Leányka and Ezerjó) were studied by measuring K (86Rb) influx rates under near-equilibrium conditions. For this purpose, one-node cuttings were rooted and grown in nutrient solutions with different K supplies. The transport data are discussed along with K, Na, Mg and Ca contents of roots, petioles and leaf blades. It was found that the effective K-utilizer variety, Leányka, possesses efficient uptake and translocation mechanisms while these transport systems were lacking in the inefficient K-utilizer Ezerjó. Since the data presented are in good agreement with practical experiences for the utilization of K by the two cultivars, the method seems to be suitable for the selection of the most effective K-utilizer varieties

    Non-CpG Oligonucleotides Exert Adjuvant Effects by Enhancing Cognate B Cell-T Cell Interactions, Leading to B Cell Activation, Differentiation, and Isotype Switching

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    Natural and synthetic nucleic acids are known to exert immunomodulatory properties. Notably, nucleic acids are known to modulate immune function via several different pathways and various cell types, necessitating a complex interpretation of their effects. In this study we set out to compare the effects of a CpG motif containing oligodeoxynucleotide (ODN) with those of a control and an inhibitory non-CpG ODN during cognate B cell-T cell interactions. We employed an antigen presentation system using splenocytes from TCR transgenic DO11.10 mice and the ovalbumin peptide recognized by the TCR as model antigen. We followed early activation events by measuring CD69 expression, late activation by MHC class II expression, cell division and antibody production of switched, and nonswitched isotypes. We found that both of the tested non-CpG ODN exerted significant immunomodulatory effects on early T cell and on late B cell activation events. Importantly, a synergism between non-CpG effects and T cell help acting on B cells was observed, resulting in enhanced IgG production following cognate T cell-B cell interactions. We propose that non-CpG ODN may perform as better adjuvants when a strong antigen-independent immune activation, elicited by CpG ODNs, is undesirable

    Recent advances using FcRn overexpression in transgenic animals to overcome impediments of standard antibody technologies to improve the generation of specific antibodies.

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    This review illustrates the salutary effects of neonatal Fc receptor (FcRn) overexpression in significantly improving humoral immune responses in the generation of antibodies for immunotherapy and diagnostics. These include: (1) improved IgG protection; (2) augmented antigen-specific humoral immune response with larger numbers of antigen specific B cells, thus offering a wider spectrum of clones; (3) generation of antibodies against weakly immunogenic antigens; (4) significant improvements in the number and substantial developments in the diversity of hybridomas. FcRn transgenesis thus confers a number of practical benefits, including faster antibody production, higher antibody yields and improved generation of hybridomas for monoclonal antibody production. Notably, these efficiencies in polyclonal antibody production were also demonstrated in FcRn transgenic rabbits. Overall, FcRn transgenic animals yield more antibodies and provide a route to the generation of antibodies against antigens of low immunogenicity that are difficult to obtain using currently available methods

    Label-Free Optical Monitoring Of The Adhesion And Spreading Of Human Cells: High Throughput Analysis With Superior Sensitivity And Time Resolution

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    Here, we briefly discuss the past, present, and possible future of label-free optical biosensors in cell adhesion research. Currently available optical biosensors possess outstanding potentials still not rightfully recognized and still waiting to be fully exploited in the field. Thus, during the description we give special emphasis to the advantages the state-of-the-art optical cell-based biosensors possess as compared to microscope- or force- measurement based techniques that are currently much more generally used to characterize cell adhesion. To name here only a few, they enable label-free detection close to a planar sensor surface, have high sensitivity, and generate superior quality kinetic data. Such information-rich kinetic data, in turn, can be subjected to in-depth comparative and kinetic analysis. To exemplify the importance of in-depth kinetic analysis, we review a recent study, in which the Epic BenchTop high-throughput optical biosensor was used to measure the dependence of adhesion kinetics on the surface density of integrin ligands. Based on the kinetically analyzed data, a model enabling the label-free determination of the dissociation constant for the interaction between adhesion ligands and their native cell membrane receptors has been constructed

    High sugar content of European commercial baby foods and proposed updates to existing recommendations

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    The aim was to determine whether commercial baby foods marketed within Europe (up to 36 months of age) have inappropriate formulation and high sugar content and to provide suggestions to update European regulations and recommendations as part of a nutrient profile model developed for this age group. The latter was produced following recommended World Health Organization (WHO) steps, including undertaking a rapid literature review. Packaging information from countries across the WHO European region was used to determine mean energy from total sugar by food category. The percentage of products containing added sugar and the percentage of savoury meal‐type products containing pureed fruit were also calculated. A total of 2,634 baby foods from 10 countries were summarised: 768 sold in the United Kingdom, over 200 each from Denmark (319), Spain (241), Italy (430) and Malta (243) and between 99–200 from Hungary, Norway, Portugal, Estonia and Slovenia. On average, approximately a third of energy in baby foods in these European countries came from total sugar, and for most food categories, energy from sugar was higher than 10%. Use of added sugars was widespread across product categories, with concentrated fruit juice most commonly used. Savoury meal‐type purees did not contain added sugars except in United Kingdom and Malta; however, fruit as an ingredient was found in 7% of savoury meals, most frequently seen in UK products. Clear proposals for reducing the high sugar content seen in commercial baby foods were produced. These suggestions, relating to both content and labelling, should be used to update regulations and promote product reformulation

    Phenotypic variation within European carriers of the Y-chromosomal gr/gr deletion is independent of Y-chromosomal background.

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    BackgroundPrevious studies have compared sperm phenotypes between men with partial [1] deletions within the AZFc region of the Y chromosome with non-carriers, with variable results. Here, we have investigated a separate question, the basis of the variation in sperm phenotype within gr/gr deletion carriers, which ranges from normozoospermia to azoospermia. Differences in the genes removed by independent gr/gr deletions, the occurrence of subsequent duplications or the presence of linked modifying variants elsewhere on the chromosome have been suggested as possible causal factors. We set out to test these possibilities in a large sample of gr/gr deletion carriers with known phenotypes spanning the complete range.ResultsWe assembled a collection of 169 men diagnosed with gr/gr deletions from six centres in Europe and one in Australia, and characterized the DAZ and CDY1 copies retained, the presence or absence of duplications and the Y-chromosomal haplogroup. Although our study had good power to detect factors that accounted for 655.5% of the variation in sperm concentration, no such factor was detected. A negative effect of gr/gr deletions followed by b2/b4 duplication was observed within the normospermic group, which remains to be further explored in a larger study population. Finally, we observed significant geographical differences in the frequency of different subtypes of gr/gr deletions which may have relevance for the interpretation of case control studies dealing with admixed populations.ConclusionsWe conclude that the phenotypic variation of gr/gr carriers in men of European origin is largely independent of the Y-chromosomal background

    Substantial variation across geographic regions in the obesity prevalence among 6–8 years old Hungarian children (COSI Hungary 2016)

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    Abstract Background There have been previous representative nutritional status surveys conducted in Hungary, but this is the first one that examines overweight and obesity prevalence according to the level of urbanization and in different geographic regions among 6–8-year-old children. We also assessed whether these variations were different by sex. Methods This survey was part of the fourth data collection round of World Health Organization (WHO) Childhood Obesity Surveillance Initiative which took place during the academic year 2016/2017. The representative sample was determined by two-stage cluster sampling. A total of 5332 children (48.4% boys; age 7.54 ± 0.64 years) were measured from all seven geographic regions including urban (at least 500 inhabitants per square kilometer; n = 1598), semi-urban (100 to 500 inhabitants per square kilometer; n = 1932) and rural (less than 100 inhabitants per square kilometer; n = 1802) areas. Results Using the WHO reference, prevalence of overweight and obesity within the whole sample were 14.2, and 12.7%, respectively. According to the International Obesity Task Force (IOTF) reference, rates were 12.6 and 8.6%. Northern Hungary and Southern Transdanubia were the regions with the highest obesity prevalence of 11.0 and 12.0%, while Central Hungary was the one with the lowest obesity rate (6.1%). The prevalence of overweight and obesity tended to be higher in rural areas (13.0 and 9.8%) than in urban areas (11.9 and 7.0%). Concerning differences in sex, girls had higher obesity risk in rural areas (OR = 2.0) but boys did not. Odds ratios were 2.0–3.4 in different regions for obesity compared to Central Hungary, but only among boys. Conclusions Overweight and obesity are emerging problems in Hungary. Remarkable differences were observed in the prevalence of obesity by geographic regions. These variations can only be partly explained by geographic characteristics. Trial registration Study protocol was approved by the Scientific and Research Ethics Committee of the Medical Research Council (61158–2/2016/EKU)
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