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11.
Klara Brixius Persephone Savvidou-Zaroti Uwe Mehlhorn Wilhelm Bloch Evangelia G. Kranias Robert H. G. Schwinger 《Basic research in cardiology》2002,97(7)
In human failing myocardium, an increased Ca 2+-sensitivity of myofilament tension development has been described in Triton X skinned cardiac myocytes compared to cardiomyocytes obtained from non-failing human donor hearts. The present study aimed to investigate whether there are functional implications of the increased Ca 2+-sensitivity in heart failure and whether alterations of myofilament function are already obvious at earlier stages of heart failure, such as in cardiac hypertrophy or whether alterations of the intracellular Ca 2+-homeostasis are able to induce alterations in myofilament function. Ca 2+-activated tension development was measured in Triton X-skinned fibers from human failing and non-failing myocardium. Ca 2+-sensitivity of myofilament tension development was significantly shifted to the left in human failing myocardium. Plots of diastolic free Ca 2+ versus diastolic tension development showed that in a range of similar diastolic Ca 2+-concentrations, diastolic tension was significantly enhanced in the failing hearts. The Ca 2+/tension relationship was shifted to the right in Triton X-skinned fiber preparations from transgenic renin overexpressing rats (TG(mREN2)27), shown to have concentric hypertrophy. In addition, the Ca 2+/tension relationship was unchanged in phospholamban knock-out mice with an increased systolic Ca 2+ (and enhanced diastolic Ca 2+-load). It is concluded that the increased Ca 2+-sensitivity of myofilament tension observed in single cardiomyocytes from failing human myocardium may be a phenomenon also present in multicellular preparations and may contribute to the diastolic dysfunction observed in human heart failure. Alterations of myofilament function occur at very early stages of heart failure and may be species dependent, or dependent on intracellular free Ca 2+-levels. 相似文献
12.
13.
Leticia Díez-Quijada Klara Hercog Martina tampar Metka Filipi
Ana M. Camen ngeles Jos Bojana
egura 《Toxins》2020,12(12)
Simultaneous occurrence of cylindrospermopsin (CYN) and microcystin-LR (MCLR) has been reported in the aquatic environment and thus human exposure to such mixtures is possible. As data on the combined effects of CYN/MCLR are scarce, we aimed to investigate the adverse effects related to genotoxic activities induced by CYN (0.125, 0.25 and 0.5 µg/mL) and MCLR (1 µg/mL) as single compounds and their combinations in HepG2 cells after 24 and 72 h exposure. CYN and CYN/MCLR induced DNA double-strand breaks after 72 h exposure, while cell cycle analysis revealed that CYN and CYN/MCLR arrested HepG2 cells in G0/G1 phase. Moreover, CYN and the combination with MCLR upregulated CYP1A1 and target genes involved in DNA-damage response (CDKN1A, GADD45A). Altogether, the results showed that after 72 h exposure genotoxic activity of CYN/MCLR mixture was comparable to the one of pure CYN. On the contrary, MCLR (1 µg/mL) had no effect on the viability of cells and had no influence on cell division. It did not induce DNA damage and did not deregulate studied genes after prolonged exposure. The outcomes of the study confirm the importance of investigating the combined effects of several toxins as the effects can differ from those induced by single compounds. 相似文献
14.
Nicole K. Leibold Wolfgang Viechtbauer Liesbet Goossens Klara De Cort Eric J. Griez Inez Myin-Germeys Harry W.M. Steinbusch Daniël L.A. van den Hove Koen R.J. Schruers 《Biological psychology》2013
Inhaling carbon dioxide (CO2)-enriched air induces fear and panic symptoms resembling real-life panic attacks, the hallmark of panic disorder. The present study aimed to describe the emotional and cardiovascular effects evoked by inhaling CO2, taking shortcomings of previous studies into account. Healthy volunteers underwent a double inhalation of 0, 9, 17.5, and 35% CO2, according to a randomized, cross-over design. In addition to fear, discomfort, and panic symptom ratings, blood pressure and heart rate were continuously monitored. Results showed a dose-dependent increase in all self-reports. Systolic and diastolic blood pressure rose with increasing CO2 concentration, whereas heart rate results were less consistent. Diastolic blood pressure and heart rate variation correlated with fear and discomfort. Based on this relationship and the observation that the diastolic blood pressure most accurately mimicked the degree of self-reported emotions, it might serve as a putative biomarker to assess the CO2-reactivity in the future. 相似文献
15.
Bayram Ozlem Haskologlu Sule Bayrakoğlu Deniz Bal Sevgi Kostel Islamoglu Candan Cipe Funda Erol Kendirli Tanil Kursun Nazmiye Guner Sukru Nail Yildiran Alisan Bozdogan Gunseli Yuksek Mutlu Reisli Ismail Dalva Klara Aytekin Caner Boztug Kaan Dogu Figen Ikinciogullari Aydan 《Journal of clinical immunology》2021,41(7):1563-1573
Journal of Clinical Immunology - Severe combined immunodeficiency is an inborn error of immunity characterized by impairments in the numbers and functions of T and B lymphocytes due to various... 相似文献
16.
The impact of donor age and sex on the nucleated cell count and CD34 count in healthy bone marrow donors 下载免费PDF全文
Elif Unal Ince Talia Ileri Figen Dogu Can Ates Hasan Cakmakli Klara Dalva Aydan Ikinciogullari Zumrut Uysal Mehmet Ertem 《Pediatric transplantation》2015,19(4):385-390
BM remains an important source of stem cells. The BM characteristics change with age but the estimation of CD34 calculation of one CD34+ cell per 100 nucleated cells is used for all donors including pediatric donors in the operating room before getting the actual CD34 count. In order to see whether this formula is applicable for pediatric donors, we designed a retrospective study to see the affect of the age and sex on the BM NCC, CD34 count, and CD34/NCC ratios. Ninety‐eight BM collections from 91 related donors were evaluated retrospectively (median age: nine yr [1.5–54 yr]; M/F: 41/50). A significant negative correlation was found between the donor age and NCC (r = −0.229, p < 0.05), CD34 count (r = −0.563, p < 0.01), and CD34/NCC (r = −0.664, p < 0.01). The negative correlation for CD34 count and CD34/NCC persisted in female and male donor groups. When donors younger than 16 yr of age were compared with the older donor group, the median NCC, median CD34 count, and CD34/NCC were significantly lower in the older group (p < 0.01). Age and sex have to be taken into consideration to avoid unnecessary high‐volume collections and increased operating room time in the younger donors. 相似文献
17.
Line Lykke Andersen Nanna M?rk Line S. Reinert Emil Kofod-Olsen Ryo Narita Sofie E. J?rgensen Kristian A. Skipper Klara H?ning Hans Henrik Gad Lars ?stergaard Torben F. ?rntoft Veit Hornung S?ren R. Paludan Jacob Giehm Mikkelsen Takashi Fujita Mette Christiansen Rune Hartmann Trine H. Mogensen 《The Journal of experimental medicine》2015,212(9):1371-1379
18.
Sonja Jacobsen Marina Höhne Andreas Mas Marques Klara Beslmüller C.-Thomas Bock Sandra Niendorf 《The Journal of infection》2018,76(5):457-464
Objectives
In order to analyze the molecular epidemiology of human astroviruses (HAstV) in Germany, a retrospective long-term study was performed to characterize circulating human astrovirus in patients with acute gastroenteritis in Germany.Methods
A total of 2877 stool samples, collected between January 2010 and December 2015 from sporadic cases and outbreaks of acute gastroenteritis were retrospectively analyzed for astrovirus. A two-step PCR algorithm was developed and used to identify and characterize human astrovirus infections.Results
Overall, 143 samples were astrovirus-positive (5.0%). Astrovirus infection was most frequently detectable in samples from children of 3–4 years (15%) followed by children of 1–2 years (8.6%), detection rates in adults were lower (1%–3.6%). A high number (71.3%) of co-infections, mainly with noro- or rotaviruses, were identified. Genotyping revealed that at least ten genotypes from all four human MAstV species were circulating in the study population. HAstV-1 was predominant in different age groups. Novel HAstV (MLB and VA genotypes) were also circulating in Germany.Conclusion
Our findings give new insights into the circulation and genetic diversity of human astroviruses in patients with acute gastroenteritis. The novel HAstV-MLB and -VA genotypes could be characterized firstly in Germany while the analysis showed that these viruses have been dispersed in Germany since 2011 as a causative agent of acute gastroenteritis. 相似文献19.
Gabor Veress Zoltan Meszar Dora Muszil Antonio Avelino Klara Matesz Ken Mackie Istvan Nagy 《Brain structure & function》2013,218(3):733-750
The cannabinoid 1 (CB1) receptor is expressed by a sub-population of primary sensory neurons. However, data on the neurochemical identity of the CB1 receptor-expressing cells, and CB1 receptor expression by the peripheral and central terminals of these neurons are inconsistent and limited. We characterised CB1 receptor expression in dorsal root ganglia (DRG) and spinal cord at the lumbar 4–5 level, as well as in the urinary bladder and glabrous skin of the hindpaw. About 1/3 of DRG neurons exhibited immunopositivity for the CB1 receptor, the majority of which showed positivity for the nociceptive markers calcitonin gene-related peptide (CGRP) or/and Griffonia (bandeiraea) simplicifolia IB4 isolectin-binding. Virtually all CB1 receptor-immunostained fibres showed immunopositivity for CGRP in the skin, while very few did in the urinary bladder. No CB1 receptor-immunopositive nerve fibres were IB4 positive in either peripheral tissue. Spinal laminae I and II-outer showed the highest density of CB1 receptor-immunopositive punctae, the majority of which showed positivity for CGRP or/and IB4 binding. These data indicate that a major sub-population of nociceptive primary sensory neurons expresses CB1 receptors that are transported to both peripheral and central terminals of these cells. Therefore, the present data suggest that manipulation of endogenous CB1 receptor agonist levels in these areas may significantly reduce nociceptive input into the spinal cord. 相似文献
20.
Giuseppe Rengo Gennaro Pagano Dino Franco Vitale Roberto Formisano Klara Komici Laura Petraglia Valentina Parisi Grazia Daniela Femminella Claudio de Lucia Stefania Paolillo Alessandro Cannavo Emilio Attena Teresa Pellegrino Santo Dellegrottaglie Alessia Memmi Bruno Trimarco Alberto Cuocolo Pasquale Perrone Filardi Dario Leosco Nicola Ferrara 《European journal of nuclear medicine and molecular imaging》2016,43(13):2392-2400