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21.
Seventy-five unrelated hemophilia A patients from India were analyzed for factor VIII gene defects. Intron 22 inversion was identified in 22 patients and intron 1 inversion in 2 patients. In the remaining 51 patients without inversions screening the FVIII gene by denaturing high performance liquid chromatography (DHPLC) revealed 42 different mutations in 44 unrelated subjects. These included 14 missense, 7 nonsense, 9 splice site, 8 deletional, 3 insertional mutations and one indel mutation. Of these, 32 were novel gene alterations. The hotspots included intron 22 inversion, CpG and adenine runs. 相似文献
22.
Red blood cells treated with the amustaline (S‐303) pathogen reduction system: a transfusion study in cardiac surgery 下载免费PDF全文
Veronika Brixner Arndt‐Holger Kiessling Katharina Madlener Markus M. Müller Johannes Leibacher Sarah Dombos Iuliia Weber Hans‐Ulrich Pfeiffer Christof Geisen Michael Schmidt Reinhard Henschler Anne North Norman Huang Nina Mufti Anna Erickson Christine Ernst Salvador Rico Richard J. Benjamin Laurence M. Corash Erhard Seifried 《Transfusion》2018,58(4):905-916
23.
24.
Zimmermann A Pöllinger B Rieber J König A Erhard I Krötz F Sohn HY Kantlehner R Haimerl W Dühmke E Leibig M Theisen K Klauss V Schiele TM 《Zeitschrift für Kardiologie》2005,94(4):239-246
Summary
In-stent restenosis (ISR) represents the major limitation of stent implantation. Treatment, although of relative technical ease, is unsatisfactory due to a high incidence of recurrent restenosis. Vascular brachytherapy (VBT) has emerged as a powerful adjunct therapeutic modality to treat ISR. Inhibition of neointima formation has been regarded as the relevant mechanism of action. Yet, positive remodelling has been suspected as another contributing factor. Since only very few precise analyses of the extent, distribution and time course of the respective mechanims exist, the goal of the present study was to describe the changes of the vessel geometry at the target lesion and at the reference site following angioplasty and VBT of ISR in 42 patients by means of quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) before and after the index procedure and at the 3 and 6 month follow-up.By QCA the acute lumen gain measured 2.2±0.8 mm, the late lumen loss at 3 months was 0.1±0.5 mm and at 6 months 0.4±0.7 mm. By IVUS luminal cross-sectional area increased from 1.5±1.2 mm2 to 7.9±1.9 mm2 (p<0.001). The intima hyperplasia cross-sectional area at 3 months was only 0.2±1.0 mm2 (p=0.191), but increased to 0.7±0.6 mm2 (p<0.001) at 6 months resulting in a lumen cross-sectional area of 7.1±1.7 mm2. Stent dimensions did not show any significant changes over time. The external elastic membrane cross-sectional area at 3 months increased by 1.3±1.9 mm2 (p<0.001), and showed a further increase by 0.7±2.9 mm2 at 6 months. Positive remodelling could be demonstrated also at the reference segment.In conclusion the absolute amount of intima hyperplasia during a 6-month follow-up period after VBT of ISR is low and most pronounced between the third and sixth month. Besides this, predominantly within the first 3 months of follow-up, significant positive remodelling could be demonstrated at the target lesion and at the reference site. Both observed effects may contribute to the preservation of the vessel lumen.Diese Publikation enthält die Ergebnisse der Promotionsarbeit von Frau Andrea Zimmermann 相似文献
25.
Fasske Erhard Morgenroth Konrad 《Journal of cancer research and clinical oncology》1958,62(4):375-382
Zusammenfassung Im Rahmen einer größeren Untersuchung über die Möglichkeiten einer Früherkennung bösartiger Tumoren in der Mundhöhle werden 22 verschiedene Mundhöhlencarcinome auf ihren Gehalt an Glykogen untersucht. Dabei ergibt sich gegenüber den Carcinomen der Portio uteri einrelativ hoher Prozentsatz glykogenhaltiger Carcinome. Vergleichsweise werden daneben die Glykogenverhältnisse der normalen menschlichen Mundschleimhaut an 432 Mundschleimhautexcisionen lebender Patienten histochemisch untersucht und ein unterschiedlicher Glykogengehalt in den einzelnen Mundhöhlenregionen aufgedeckt. Innerhallb der Epithelschichten bleibt das Stratum germinativum stets glykogenfrei. Vergleichende Untersuchungen an der glykogenfreien Mundschleimhaut von Ratten und Kaninchen konnten nachweisen, daß Teilungszellen zur Glykogensynthese nicht in der Lage sind. Zur Klärung der Frage, ob der Glykogengehalt innerhalb der Mundschleimhaut dem Insulin-Adrenalin-Regulator unterliegt, wurden darüber hinaus die Mundschleimhautverhältnisse mittels der Schillerschen Jodlösung an 1661 Diabetikern geprüft und die Mundschleimhautexcisionen von 32 Diabetikern histochemisch ausgewertet und zum jeweiligen Blutzuckerspiegel in Relation gesetzt. Die Ergebnisse sprechen dafür, daß der Glykogengehalt der Mundschleimhaut nicht vom Insulinspiegel abhängt. Da sich für Phosphorylierungsvorgänge Anhaltspunkte nicht ergaben, wird das Glykogen der Mundschleimhaut und der Mundhöhlencarcinome als Stapelungsglykogen angesprochen. 相似文献
26.
Sixten Krper Bernd Jahrsdrfer Victor M. Corman Jan Pilch Patrick Wuchter Rainer Blasczyk Rebecca Müller Torsten Tonn Tamam Bakchoul Richard Schfer David Juhl Tatjana Schwarz Nina Gdecke Thomas Burkhardt Michael Schmidt Thomas Appl Hermann Eichler Harald Klüter Christian Drosten Erhard Seifried Hubert Schrezenmeier 《Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft fur Transfusionsmedizin und Immunhamatologie》2021,48(3):137
BackgroundConvalescent plasma is one of the treatment options for COVID-19 which is currently being investigated in many clinical trials. Understanding of donor and product characteristics is important for optimization of convalescent plasma.MethodsPatients who had recovered from COVID-19 were recruited as donors for COVID-19 convalescent plasma (CCP) for a randomized clinical trial of CCP for treatment of severe COVID-19 (CAPSID Trial). Titers of neutralizing antibodies were measured by a plaque-reduction neutralization test (PRNT). Correlation of antibody titers with host factors and evolution of neutralizing antibody titers over time in repeat donors were analysed.ResultsA series of 144 donors (41% females, 59% males; median age 40 years) underwent 319 plasmapheresis procedures providing a median collection volume of 850 mL and a mean number of 2.7 therapeutic units per plasmapheresis. The majority of donors had a mild or moderate course of COVID-19. The titers of neutralizing antibodies varied greatly between CCP donors (from <1:20 to >1:640). Donor factors (gender, age, ABO type, body weight) did not correlate significantly with the titer of neutralizing antibodies. We observed a significant positive correlation of neutralization titers with the number of reported COVID-19 symptoms and with the time from SARS-CoV-2 diagnosis to plasmapheresis. Neutralizing antibody levels were stable or increased over time in 58% of repeat CCP donors. Mean titers of neutralizing antibodies of first donation and last donation of repeat CCP donors did not differ significantly (1:86 at first compared to 1:87 at the last donation). There was a significant correlation of neutralizing antibodies measured by PRNT and anti-SARS-CoV-2 IgG and IgA antibodies which were measured by ELISA. CCP donations with an anti-SARS-CoV-2 IgG antibody content above the 25th percentile were substantially enriched for CCP donations with higher neutralizing antibody levels.ConclusionWe demonstrate the feasibility of collection of a large number of CCP products under a harmonized protocol for a randomized clinical trial. Titers of neutralizing antibodies were stable or increased over time in a subgroup of repeat donors. A history of higher number of COVID-19 symptoms and higher levels of anti-SARS-CoV-2 IgG and IgA antibodies in immunoassays can preselect donations with higher neutralizing capacity. 相似文献
27.
Evaluation of the effectiveness of a pathogen inactivation technology against clinically relevant transfusion‐transmitted bacterial strains 下载免费PDF全文
28.
Schiele TM Rieber J König A Leibig M Erhard I Theisen K Siebert U Klauss V 《The American journal of cardiology》2004,94(7):917-921
In-stent restenosis (ISR), especially after vascular brachytherapy, is a therapeutic challenge. Sirolimus-eluting stent implantation is a promising new option for the treatment of patients with ISR. The efficacy of sirolimus-eluting stent implantation for the treatment of patients with their first episodes of ISR and with recurrent ISR due to the failure of vascular brachytherapy was compared using intravascular ultrasound imaging. 相似文献
29.
Martin Kaltenpoth Kerstin Roeser-Mueller Sabrina Koehler Ashley Peterson Taras Y. Nechitaylo J. William Stubblefield Gudrun Herzner Jon Seger Erhard Strohm 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(17):6359-6364
Many insects rely on symbiotic microbes for survival, growth, or reproduction. Over evolutionary timescales, the association with intracellular symbionts is stabilized by partner fidelity through strictly vertical symbiont transmission, resulting in congruent host and symbiont phylogenies. However, little is known about how symbioses with extracellular symbionts, representing the majority of insect-associated microorganisms, evolve and remain stable despite opportunities for horizontal exchange and de novo acquisition of symbionts from the environment. Here we demonstrate that host control over symbiont transmission (partner choice) reinforces partner fidelity between solitary wasps and antibiotic-producing bacteria and thereby stabilizes this Cretaceous-age defensive mutualism. Phylogenetic analyses show that three genera of beewolf wasps (Philanthus, Trachypus, and Philanthinus) cultivate a distinct clade of Streptomyces bacteria for protection against pathogenic fungi. The symbionts were acquired from a soil-dwelling ancestor at least 68 million years ago, and vertical transmission via the brood cell and the cocoon surface resulted in host–symbiont codiversification. However, the external mode of transmission also provides opportunities for horizontal transfer, and beewolf species have indeed exchanged symbiont strains, possibly through predation or nest reuse. Experimental infection with nonnative bacteria reveals that—despite successful colonization of the antennal gland reservoirs—transmission to the cocoon is selectively blocked. Thus, partner choice can play an important role even in predominantly vertically transmitted symbioses by stabilizing the cooperative association over evolutionary timescales.Cooperation is ubiquitous in nature, yet it presents a conundrum to evolutionary biology because acts that are beneficial to the receiver but costly to the actor should not be favored by natural selection (1). In interspecific associations (i.e., symbioses), the two most important models to explain the maintenance of cooperation are partner fidelity and partner choice (2, 3). In partner-fidelity associations, host and symbiont interact repeatedly and reward cooperating individuals while punishing cheaters, thereby reinforcing mutually beneficial interactions (2, 4). In partner-choice associations, individuals may interact only once, but one member can select its partner in advance of any possible exploitation (2, 4). Partner choice appears to select for cooperative strains among environmentally acquired microbial symbionts, e.g., the bioluminescent Vibrio fischeri bacteria of squids (5), the nitrogen-fixing rhizobia of legumes (6), and mycorrhizal fungi of plants (7). By contrast, partner fidelity is generally assumed to be the major stabilizing force in the widespread and ecologically important vertically transmitted symbioses of insects (4).However, localization and transmission routes of mutualistic bacteria in insects are diverse, and the differences across symbiotic systems have important implications for the evolutionary trajectory of the associations. Symbionts with an obligate intracellular lifestyle are usually tightly integrated into the host’s metabolism (e.g., ref. 8) and development (9), and the mutual interdependence of both partners coincides with perfect vertical symbiont transmission. Over evolutionary timescales, the high degree of partner fidelity results in host–symbiont cocladogenesis, and, concordantly, phylogenies of hosts and their intracellular symbionts are often found to be congruent (10–13). Although such a pattern is also observed for some extracellular symbioses with especially tight host–symbiont integration (14, 15), the ability of many extracellularly transmitted symbionts to spend part of their life cycle outside of the host’s body is often reflected in more or less extensive horizontal transmission or de novo acquisition of symbionts from the environment (16, 17). In these cases, partner choice mechanisms are expected to ensure specificity in the establishment and maintenance of the association (18). The nature of such control mechanisms, however, remains poorly understood.Although many of the well-studied mutualistic associations in insects have a nutritional basis (19, 20), an increasing number of symbioses for the defense of the host against predators (21), parasitoids (22), or pathogens (23–25) have recently been discovered. Among defensive symbionts, Actinobacteria are particularly prevalent, probably due to their ubiquity in the soil and their ability to produce secondary metabolites with antibiotic properties (23). Antibiotic-producing actinobacterial symbionts have been discovered on the cuticle of leaf-cutting ants (26), in the fungal galleries of a bark beetle (27), and in the antennae and on cocoons of beewolf wasps (28). While in the former two cases the symbionts have been implicated in the defense of the hosts’ nutritional resources against competing fungi (26, 27), the beewolves’ bacteria protect the offspring in the cocoon against pathogenic microorganisms (28, 29).Beewolves are solitary wasps in the genera Philanthus, Trachypus, and Philanthinus (Hymenoptera, Crabronidae, Philanthini). They engage in a defensive alliance with the Actinobacterium ‘Candidatus Streptomyces philanthi’ (CaSP) (28, 30, 31), which is cultivated by female beewolves in specialized antennal gland reservoirs (32). The uniqueness and complexity of the glands suggest a long history of host adaptation towards cultivating its actinobacterial symbionts (32). From the antennae, the streptomycetes are secreted into the brood cell, taken up by the larva, and incorporated into its cocoon (33), where they provide protection against pathogenic fungi and bacteria (28) by producing at least nine different antimicrobial compounds (29). Weeks or months later, eclosing adult females acquire the bacteria from the cocoon surface (33), thus completing the vertical transmission of CaSP. However, this mode of transmission provides opportunities for the horizontal transfer of symbionts among beewolf species or the de novo uptake of bacteria from the environment. Despite these opportunities, a monophyletic clade of CaSP strains has previously been found in 31 species of beewolves, suggesting an ancient and highly coevolved relationship (30, 31, 34).Here we combine cophylogenetic analyses of beewolves and their vertically transmitted defensive symbionts with experimental manipulation of symbiont infection status and subsequent observations of transmission from female antennal gland reservoirs into the brood cell to (i) reconstruct the coevolutionary history of the symbiosis, (ii) estimate the age of the symbiosis, (iii) elucidate the ancestral lifestyle of the symbionts, and (iv) assess the importance of partner fidelity and partner choice for the long-term stability of the association. 相似文献
30.
Nicole Scheuing Frank Best Albrecht Dapp Ines Dreyhaupt Hans-Peter Filz Dietmar Krakow Wolfgang Lang Erhard Siegel Andrej Zeyfang Reinhard W. Holl 《Parkinsonism & related disorders》2013,19(7):687-692
BackgroundEspecially in older people, physicians are faced with the coexistence of type 2 diabetes mellitus (T2DM) and Parkinson's disease (PD). Therefore, this research aimed to compare diabetes endpoints between T2DM with and without PD.MethodsBased on the standardized, multicenter, prospective DPV database, 178,992 T2DM patients (≥40 years) were analyzed. 1579 were diagnosed with PD and/or received specific treatment. Hierarchical multivariable regression models were used for group comparisons; adjusted estimates based on observed marginal frequencies were calculated.ResultsPD patients were significantly older (77.9 vs. 70.0 years; p < 0.0001) and had a longer diabetes duration (10.3 vs. 8.4 years; p < 0.0001). In young PD patients (<50 years), percentage of females was significantly higher compared to age-matched T2DM patients without PD or people of the German population (66.7 vs. 38.1 vs. 49.0%; p < 0.0001, p < 0.02).After demographic adjustment, T2DM patients with PD showed a significantly lower HbA1c (58.0 vs. 60.3 mmol/mol; p < 0.0001), OAD/GLP-1 treatment (41.9 vs. 45.9%; p < 0.01) and frequency of dyslipidemia (62.0 vs. 64.5%; p < 0.05). In contrast, rates of insulin therapy (57.8 vs. 54.8%; p < 0.05), hypertension (73.3 vs. 68.6%; p < 0.001), antihypertensive medication (60.4 vs. 56.1%; p < 0.01), stroke (12.0 vs. 7.3%; p < 0.0001), dementia (9.2 vs. 2.6%; p < 0.0001) and repeated inpatient care (15.7 vs. 12.0%; p < 0.0001) were significantly higher and duration of hospital stay (6.2 vs. 4.7 days; p < 0.0001) was significantly longer in T2DM with PD.ConclusionClear demographic and clinical differences were observed between T2DM with and without PD. In PD patients, metabolic control is better, potentially due to more intensive medical care. 相似文献