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1.
Meike Lippelt Theresa Sanabria de Isele Manfred Kist 《Clinical microbiology and infection》1997,3(2):229-235
Objective: To carry out an epidemiologic evaluation of Salmonella enterica subsp. enterica serovar Enteritidis outbreaks in households and small communities by means of rRNA gene restriction pattern analysis (ribotyping).
Method: One hundred Enteritidis isolates dating from 1989 to 1994 which could be allocated epidemiologically to different sources or to small community outbreaks were investigated with ribotyping, a fingerprinting method in which bacterial DNA is hybridized with the biotin-labeled plasmid pKK 3535 containing a ribosomal RNA operon of Escherichia coli to determine the ribosomal RNA gene restriction patterns.
Results: Four different ribotyping patterns were found with the restriction endonuclease Sma I and nine with Sph I. Ribotypes of isolates which could be allocated epidemiologically to a common source usually corresponded. Almost 60% of the Enteritidis infections had the ribotyping pattern Sph I-A. In contrast, this pattern was not found in any of the five Enteritidis strains isolated in 1989. The suspicion that Enteritidis phage type 4 infections are caused by consumption of insufficiently heated eggs is supported by the fact that the ribotyping pattern Sph 1-A was found in isolates from eggs and from human specimens.
Conclusions: As patterns Sph I-A and Sma I-J appeared in 58% and 75% of the isolates, respectively, ribotyping cannot be used for the differentiation between various outbreaks with these two patterns. In cases where the Enteritidis strains showed less frequent patterns, ribotyping seems to be a practical tool for the identification of infection chains. In addition newly appearing ribotyping patterns can give information about the epidemiologic development of Enteritidis infection. 相似文献
Method: One hundred Enteritidis isolates dating from 1989 to 1994 which could be allocated epidemiologically to different sources or to small community outbreaks were investigated with ribotyping, a fingerprinting method in which bacterial DNA is hybridized with the biotin-labeled plasmid pKK 3535 containing a ribosomal RNA operon of Escherichia coli to determine the ribosomal RNA gene restriction patterns.
Results: Four different ribotyping patterns were found with the restriction endonuclease Sma I and nine with Sph I. Ribotypes of isolates which could be allocated epidemiologically to a common source usually corresponded. Almost 60% of the Enteritidis infections had the ribotyping pattern Sph I-A. In contrast, this pattern was not found in any of the five Enteritidis strains isolated in 1989. The suspicion that Enteritidis phage type 4 infections are caused by consumption of insufficiently heated eggs is supported by the fact that the ribotyping pattern Sph 1-A was found in isolates from eggs and from human specimens.
Conclusions: As patterns Sph I-A and Sma I-J appeared in 58% and 75% of the isolates, respectively, ribotyping cannot be used for the differentiation between various outbreaks with these two patterns. In cases where the Enteritidis strains showed less frequent patterns, ribotyping seems to be a practical tool for the identification of infection chains. In addition newly appearing ribotyping patterns can give information about the epidemiologic development of Enteritidis infection. 相似文献
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3.
Lisa Oestereich Stephanie Wurr Beate Becker-Ziaja Sabrina Bockholt Meike Pahlmann Daniel Cadar Beate M. Kümmerer Stephan Günther Romy Kerber 《Viruses》2022,14(9)
Highly pathogenic Arenaviruses, like the Lassa Virus (LASV), pose a serious public health threat in affected countries. Research and development of vaccines and therapeutics are urgently needed but hampered by the necessity to handle these pathogens under biosafety level 4 conditions. These containment restrictions make large-scale screens of antiviral compounds difficult. Therefore, the Mopeia virus (MOPV), closely related to LASV, is often used as an apathogenic surrogate virus. We established for the first time trisegmented MOPVs (r3MOPV) with duplicated S segments, in which one of the viral genes was replaced by the reporter genes ZsGreen (ZsG) or Renilla Luciferase (Rluc), respectively. In vitro characterization of the two trisegmented viruses (r3MOPV ZsG/Rluc and r3MOPV Rluc/ZsG), showed comparable growth behavior to the wild type virus and the expression of the reporter genes correlated well with viral titer. We used the reporter viruses in a proof-of-principle in vitro study to evaluate the antiviral activity of two well characterized drugs. IC50 values obtained by Rluc measurement were similar to those obtained by virus titers. ZsG expression was also suitable to evaluate antiviral effects. The trisegmented MOPVs described here provide a versatile and valuable basis for rapid high throughput screening of broadly reactive antiviral compounds against arenaviruses under BSL-2 conditions. 相似文献
4.
Meike Mitsdoerffer Lilian Aly Melanie Barz Thomas Engleitner Christopher Sie Claire Delbridge Gildas Lepennetier Rupert
llinger Monika Pfaller Benedikt Wiestler Roland Rad Bernhard Meyer Benjamin Knier Friederike Schmidt-Graf Jens Gempt Thomas Korn 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(34)
5.
Ramona Schuppner Justus Maehlmann Meike Dirks Hans Worthmann Anita B. Tryc Kajetan Sandorski Elisabeth Bahlmann Jan T. Kielstein Anja M. Giesemann Heinrich Lanfermann Karin Weissenborn 《Medicine》2016,95(6)
In an outbreak of shiga toxin-producing Escherichia coli infections and associated hemolytic-uremic syndrome (STEC O104:H4) in Germany in the year 2011 neurological complications in adult patients occurred unexpectedly frequent, ranging between 48% and 100% in different patient groups. Few is known about the long-term effects of such complications and so we performed follow-up exams on 44 of the patients treated for STEC-HUS at Hannover Medical Scool in this observational study. Standardized follow-up exams including neurological and neuropsychological assessments, laboratory testing, magnetic resonance imaging (MRI), and EEG were carried out. Subgroups were examined 2 (n = 34), 7 (n = 22), and 19 (n = 23) months after disease onset. Additionally, at the 19-month follow-up, quality of life, sleep quality, and possible fatigue were assessed.Nineteen months after disease onset 31 patients were reassessed, 22 of whom still suffered from symptoms such as fatigue, headache, and attention deficits. In the neuropsychological assessments only 39% of the patients performed normal, whereas 61% scored borderline pathological or lower. Upon reviewal, the follow-up data most prominently showed a secondary decline of cognitive function in about one-quarter of the patients. Outcome was not related to treatment or laboratory data in the acute phase of the disease nor length of hospitalization. Prognosis of STEC-HUS associated brain dysfunction in adults with regard to severity of symptoms is mostly good; some patients however still have not made a full recovery. Patients’ caretakers have to be aware of possible secondary decline of brain function as was observed in this study. 相似文献
6.
Yayouk E. Willems Conor V. Dolan Catharina E. M. van Beijsterveldt Eveline L. de Zeeuw Dorret I. Boomsma Meike Bartels Catrin Finkenauer 《Behavior genetics》2018,48(2):135-146
This study used a theoretically-derived set of items of the Achenbach System of Empirically Based Assessment to develop the Achenbach Self-Control Scale (ASCS) for 7–16 year olds. Using a large dataset of over 20,000 children, who are enrolled in the Netherlands Twin Register, we demonstrated the psychometric properties of the ASCS for parent-, self- and teacher-report by examining internal and criterion validity, and inter-rater and test–retest reliability. We found associations between the ASCS and measures of well-being, educational achievement, and substance use. Next, we applied the classical twin design to estimate the genetic and environmental contributions to self-control. Genetic influences accounted for 64–75% of the variance in self-control based on parent- and teacher-report (age 7–12), and for 47–49% of the variance in self-control based on self-report (age 12–16), with the remaining variance accounted by non-shared environmental influences. In conclusion, we developed a validated and accessible self-control scale, and show that genetic influences explain a majority of the individual differences in self-control across youth aged 7–16 years. 相似文献
7.
8.
Nils Krueger Stefanie Luebberding Mareike Oltmer Meike Streker Martina Kerscher 《Skin research and technology》2011,17(2):141-148
Background/purpose: The most commonly used method to determine the mechanical ability of skin is the creep test using suction chamber devices. Until now, there is no scientific consensus upon which skin deformation parameters and which body sites are particularly suitable to describe age‐related changes in human skin mechanics. The aim of this study was to find those mechanical skin parameters best representing influence of aging at five different body sites. Methods: A total of 120 healthy women aged 18–65, divided into four similar age groups, were included in this study. The biomechanical properties of the skin were measured using the Cutometer® MPA 580 on five body sites: cheek, neck, cleavage, volar forearm and back of the hand. In order to analyze parameters referred to 1 mm skin thickness, we also used 20 MHz sonography (DUB 20). Results: A high average correlation with age was found for the parameters Ua/Uf, Ur/Ue, Ur, Ur/Uf and Ua. Only low correlation with age was found for the parameters Uv/Ue, Uf‐Ua, Uf5/Uf, Ud/Uf and Ua5. The localizations cheek, forearm and neck showed the highest correlation with age, while cleavage showed only low correlation. Conclusion: According to the results of our study, we recommend the parameter ratio of elastic recovery to distensibility (Ur/Uf) as well as the gross elasticity (Ua/Uf) for evaluation of aging effects on the mechanical properties of skin. Their high correlation with age makes them particularly applicable to represent the influence of aging onto skin mechanical properties. Most suitable localizations to evaluate skin aging are cheek, forearm and neck. 相似文献
9.
Thom S. Lysen Hazel I. Zonneveld Ryan L. Muetzel M. Arfan Ikram Annemarie I. Luik Meike W. Vernooij Henning Tiemeier 《Journal of sleep research》2020,29(5)
Sleep problems increase with ageing. Increasing evidence suggests that sleep problems are not only a consequence of age‐related processes, but may independently contribute to developing vascular or neurodegenerative brain disease. Yet, it remains unclear what mechanisms underlie the impact sleep problems may have on brain health in the general middle‐aged and elderly population. Here, we studied sleep's relation to brain functioning in 621 participants (median age 62 years, 55% women) from the population‐based Rotterdam Study. We investigated cross‐sectional associations of polysomnographic and subjectively measured aspects of sleep with intrinsic neural activity measured with resting‐state functional magnetic resonance imaging on a different day. We investigated both functional connectivity between regions and brain activity (blood‐oxygen‐level‐dependent signal amplitude) within regions, hierarchically towards smaller topographical levels. We found that longer polysomnographic total sleep time is associated with lower blood‐oxygen‐level‐dependent signal amplitude in (pre)frontal regions. No objective or subjective sleep parameters were associated with functional connectivity between or within resting‐state networks. The findings may indicate a pathway through which sleep, in a ‘real‐life’ population setting, impacts brain activity or regional brain activity determines total sleep time. 相似文献
10.
Meike Stumpp Marian Y. Hu Frank Melzner Magdalena A. Gutowska Narimane Dorey Nina Himmerkus Wiebke C. Holtmann Sam T. Dupont Michael C. Thorndyke Markus Bleich 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(44):18192-18197
Calcifying echinoid larvae respond to changes in seawater carbonate chemistry with reduced growth and developmental delay. To date, no information exists on how ocean acidification acts on pH homeostasis in echinoderm larvae. Understanding acid–base regulatory capacities is important because intracellular formation and maintenance of the calcium carbonate skeleton is dependent on pH homeostasis. Using H+-selective microelectrodes and the pH-sensitive fluorescent dye BCECF, we conducted in vivo measurements of extracellular and intracellular pH (pHe and pHi) in echinoderm larvae. We exposed pluteus larvae to a range of seawater CO2 conditions and demonstrated that the extracellular compartment surrounding the calcifying primary mesenchyme cells (PMCs) conforms to the surrounding seawater with respect to pH during exposure to elevated seawater pCO2. Using FITC dextran conjugates, we demonstrate that sea urchin larvae have a leaky integument. PMCs and spicules are therefore directly exposed to strong changes in pHe whenever seawater pH changes. However, measurements of pHi demonstrated that PMCs are able to fully compensate an induced intracellular acidosis. This was highly dependent on Na+ and HCO3−, suggesting a bicarbonate buffer mechanism involving secondary active Na+-dependent membrane transport proteins. We suggest that, under ocean acidification, maintained pHi enables calcification to proceed despite decreased pHe. However, this probably causes enhanced costs. Increased costs for calcification or cellular homeostasis can be one of the main factors leading to modifications in energy partitioning, which then impacts growth and, ultimately, results in increased mortality of echinoid larvae during the pelagic life stage. 相似文献