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191.
Karsai D Gesztelyi R Zsuga J Jakab A Szendrei L Juhasz B Bak I Szabo G Lekli I Vecsernyes M Varga E Szentmiklosi AJ Tosaki A 《Cell biochemistry and biophysics》2007,47(1):45-52
The aim of the present study was to investigate the effect of hyperthyroidism on the trans-sarcolemmal adenosine (Ado) flux
via equilibrative and nitrobenzylthioinosine (NBTI)-sensitive nucleoside transporters (ENT1) in guinea pig atria, by assessing
the change in the Ado concentration of the interstitial fluid ([Ado]ISF) under nucleoside transport blockade with NBTI. For the assessment, we applied our novel method, which estimates the change
in [Ado]ISF utilizing the altered inotropic response to N6-cyclopentyladenosine (CPA), a relative stable selective agonist of A1 Ado receptors, by providing a relative index, the equivalent concentration of CPA. Our results show an interstitial A do
accumulation upon ENT1 blockade, which was more extensive in the hyperthyroid samples (CPA concentrations equieffective with
the surplus [Ado]ISF were two to three times higher in hyperthyroid atria than in euthyroid ones, with regard to the negative inotropic effect
of CPA and Ado). This suggests an enhanced Ado influx via ENT1 in hyperthyroid atria. It is concluded that hyperthyroidism
does not alter the prevailing direction of the Ado transport, moreover intensifies the Ado influx in the guinea pig atrium. 相似文献
192.
The bioactive lipids lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P), the enzymes that generate and degrade them, and the receptors that receive their signals are all potential therapeutic targets in cancer. LPA and S1P signalling pathways can modulate a range of cellular processes that contribute to tumourigenesis, such as proliferation and motility, and components of the signalling pathways often show aberrant expression and altered activity upon malignant transformation. This article reviews LPA- and S1P-mediated activities that might contribute to the aetiology of cancer, and examines the potential of the many antagonists that have been developed to inhibit LPA and S1P signalling pathways. In addition, the outcomes of various clinical trials using LPA- and S1P-associated targets in cancer and other diseases are described, and future directions are discussed. 相似文献
193.
194.
Dan L. Lindsley L. Sandler Bruce S. Baker Adelaide T. C. Carpenter R. E. Denell Jeffrey C. Hall Patricia A. Jacobs George L. Gabor Miklos Brian K. Davis R. C. Gethmann R. W. Hardy A. Hessler Steven M. Miller Hiroshi Nozawa Dilys M. Parry M. Gould-Somero 《Genetics》1972,71(1):157-184
By combining elements of two Y-autosome translocations with displaced autosomal breakpoints, it is possible to produce zygotes heterozygous for a deficiency for the region between the breakpoints, and also, as a complementary product, zygotes carrying a duplication for precisely the same region. A set of Y-autosome translocations with appropriately positioned breakpoints, therefore, can in principle be used to generate a non-overlapping set of deficiencies and duplications for the entire autosomal complement.-Using this method, we have succeeded in examining segmental aneuploids for 85% of chromosomes 2 and 3 in order to assess the effects of aneuploidy and to determine the number and location of dosage-sensitive loci in the Drosophila genome (Figure 5). Combining our data with previously reported results on the synthesis of Drosophila aneuploids (see Lindsley and Grell 1968), the following generalities emerge.-1. The X chromosome contains no triplo-lethal loci, few or no haplo-lethal loci, at least seven Minute loci, one hyperploid-sensitive locus, and one locus that is both triplo-abnormal and haplo-abnormal. 2. Chromosome 2 contains no triplo-lethal loci, few or no haplo-lethal loci, at least 17 Minute loci, and at least four other haplo-abnormal loci. 3. Chromosome 3 contains one triplo-lethal locus that is also haplo-lethal, few or no other haplo-lethal loci, at least 16 Minute loci, and at least six other haplo-abnormal loci. 4. Chromosome 4 contains no triplo-lethal loci, no haplo-lethal loci, one Minute locus, and no other haplo-abnormal loci.-Thus, the Drosophila genome contains 57 loci, aneuploidy for which leads to a recognizable effect on the organism: one of these is triplo-lethal and haplo-lethal, one is triplo-abnormal and haplo-abnormal, one is hyperploid-sensitive, ten are haplo-abnormal, 41 are Minutes, and three are either haplo-lethals or Minutes. Because of the paucity of aneuploid-lethal loci, it may be concluded that the deleterious effects of aneuploidy are mostly the consequence of the additive effects of genes that are slightly sensitive to abnormal dosage. Moreover, except for the single triplo-lethal locus, the effects of hyperploidy are much less pronounced than those of the corresponding hypoploidy. 相似文献
195.
Keli N. Gerken A. Desire LaBeaud Henshaw Mandi Maïna LAzou Jackson J. Gabrielle Breugelmans Charles H. King 《PLoS neglected tropical diseases》2022,16(1)
BackgroundRift Valley fever virus (RVFV) is a lethal threat to humans and livestock in many parts of Africa, the Arabian Peninsula, and the Indian Ocean. This systematic review’s objective was to consolidate understanding of RVFV epidemiology during 1999–2021 and highlight knowledge gaps relevant to plans for human vaccine trials.Methodology/Principal findingsThe review is registered with PROSPERO (CRD42020221622). Reports of RVFV infection or exposure among humans, animals, and/or vectors in Africa, the Arabian Peninsula, and the Indian Ocean during the period January 1999 to June 2021 were eligible for inclusion. Online databases were searched for publications, and supplemental materials were recovered from official reports and research colleagues. Exposures were classified into five groups: 1) acute human RVF cases, 2) acute animal cases, 3) human RVFV sero-surveys, 4) animal sero-surveys, and 5) arthropod infections. Human risk factors, circulating RVFV lineages, and surveillance methods were also tabulated. In meta-analysis of risks, summary odds ratios were computed using random-effects modeling. 1104 unique human or animal RVFV transmission events were reported in 39 countries during 1999–2021. Outbreaks among humans or animals occurred at rates of 5.8/year and 12.4/year, respectively, with Mauritania, Madagascar, Kenya, South Africa, and Sudan having the most human outbreak years. Men had greater odds of RVFV infection than women, and animal contact, butchering, milking, and handling aborted material were significantly associated with greater odds of exposure. Animal infection risk was linked to location, proximity to water, and exposure to other herds or wildlife. RVFV was detected in a variety of mosquito vectors during interepidemic periods, confirming ongoing transmission.Conclusions/SignificanceWith broad variability in surveillance, case finding, survey design, and RVFV case confirmation, combined with uncertainty about populations-at-risk, there were inconsistent results from location to location. However, it was evident that RVFV transmission is expanding its range and frequency. Gaps assessment indicated the need to harmonize human and animal surveillance and improve diagnostics and genotyping. Given the frequency of RVFV outbreaks, human vaccination has strong potential to mitigate the impact of this now widely endemic disease. 相似文献
196.
Eva Domokos-Szabolcsy Laszlo Marton Attila Sztrik Beata Babka Jozsef Prokisch Miklos Fari 《Plant Growth Regulation》2012,68(3):525-531
The uptake, accumulation and biological effects of red nano-sized elemental selenium (nanoSe) in comparison to selenate were investigated in plant system at the first time. The data clearly indicated that red nanoSe was taken up by tobacco callus cultures and rooted tobacco plantlets. The roots of regenerated plantlets accumulated selenium in very high concentrations, 2,947 ± 99 mg/kg DW, from the medium containing 530 μM nanoSe. The biological effects of nanoSe were different from the selenate ion in plant tissue culture. NanoSe (265–530 μM concentration range) stimulated the organogenesis and the growth of root system significantly (~40 %) while selenate did not show these effects at any concentration moreover inhibited both callus growth and root regeneration totally in 265–530 μM concentrations. 相似文献
197.
Andrea Mike Erzsebet Strammer Mihaly Aradi Gergely Orsi Gabor Perlaki Andras Hajnal Janos Sandor Miklos Banati Eniko Illes Alexander Zaitsev Robert Herold Charles R. G. Guttmann Zsolt Illes 《PloS one》2013,8(12)
Successful socialization requires the ability of understanding of others’ mental states. This ability called as mentalization (Theory of Mind) may become deficient and contribute to everyday life difficulties in multiple sclerosis. We aimed to explore the impact of brain pathology on mentalization performance in multiple sclerosis. Mentalization performance of 49 patients with multiple sclerosis was compared to 24 age- and gender matched healthy controls. T1- and T2-weighted three-dimensional brain MRI images were acquired at 3Tesla from patients with multiple sclerosis and 18 gender- and age matched healthy controls. We assessed overall brain cortical thickness in patients with multiple sclerosis and the scanned healthy controls, and measured the total and regional T1 and T2 white matter lesion volumes in patients with multiple sclerosis. Performances in tests of recognition of mental states and emotions from facial expressions and eye gazes correlated with both total T1-lesion load and regional T1-lesion load of association fiber tracts interconnecting cortical regions related to visual and emotion processing (genu and splenium of corpus callosum, right inferior longitudinal fasciculus, right inferior fronto-occipital fasciculus, uncinate fasciculus). Both of these tests showed correlations with specific cortical areas involved in emotion recognition from facial expressions (right and left fusiform face area, frontal eye filed), processing of emotions (right entorhinal cortex) and socially relevant information (left temporal pole). Thus, both disconnection mechanism due to white matter lesions and cortical thinning of specific brain areas may result in cognitive deficit in multiple sclerosis affecting emotion and mental state processing from facial expressions and contributing to everyday and social life difficulties of these patients. 相似文献
198.
199.
Background
One of the central problems of post-genomic biology is the understanding of regulatory network of genes. Traditionally the problem is approached from the protein-DNA interaction perspective. In recent years various types of noncoding RNAs appeared on the scene as new potent players of the game. The exact role of these molecules in gene expression control is mostly unknown at present, while their importance is generally recognized. 相似文献200.