38 results on '"Zehner R"'
Search Results
2. Technical Assistance from Lawrence Berkeley National Laboratory and National Energy Technology Laboratory to Elko Heat Company and the City of Wells, Nevada
- Author
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Spycher, N, McKoy, ML, Ayling, B, Bill, M, Bosshardt, K, Cameron, E, Creason, CG, DiGiulio, J, Dobson, P, Justman, D, Hammack, R, Miller, R, Mark-Moser, M, Rackley, I, Rose, K, Siler, D, Supp, J, Veloski, G, Zehner, R, and Zuza, A
- Abstract
Warm waters in several domestic and municipal water wells in and around the City of Wells, Nevada, along with several hot springs a few kilometers away, suggest economical geothermal resources that could meet residential and commercial space heating demands, perhaps evengeothermal electricity generation. To date, only a few low-temperature, single-user space heating applications have been developed. Under the U.S. Department of Energy’s Small Business Vouchers Pilot (SBV) Program, research teams from Lawrence Berkeley National Laboratory(LBNL) and the National Energy Technology Laboratory (NETL), in collaboration with the University of Nevada, Reno (UNR), Better Cities, and Lumos & Associates, advised the Elko Heat Company and the City of Wells in their recent drilling of a shallow geothermal gradient well, based on new field work along with a compilation and review of existing geologic, geochemical, geothermal, and geophysical data for this area. New field data include ground temperature measurements with shallow 2-meter probes and with Geoprobe holes penetrating to depths of 5 to 9 meters, new geochemical analysis of springs and wells, revision of geologic maps through geologic and structural mapping, and shallow direct current resistivity and electromagnetic induction surveys. All 51 datasets collected and created throughout the project were cataloged and categorized according to their metadata and attributes, and compiled into a data catalog and ESRI ArcGIS geodatabase and map package, all of which are available as shared, public resources through NETL’s Energy Data eXchange (EDX)1. Once assembled, 11 surface- and subsurface- spatial-datasets were incorporated into NETL’s Cumulative SpatialImpact Layers (CSIL) tool, and imported into EarthVision, a 3-dimensional visualization software, to demonstrate regions of high-data density, construct an interpolated temperature model, and identify favorable locations to drill a geothermal exploration well. Anomalouslyhigh temperatures (≥43°C) at shallow depths (5 to 9 m) were found along the north floodplain margin of the Humboldt River, northwest of the City of Wells and coinciding with the possible intersection of N-S and E-W faults. While no subsurface waters have been analyzed in this anomaly, water samples from springs and wells to the east and west of this zone were found to display differing chemical and isotopic characteristics, suggesting two different deep circulations on either side of the shallow anomaly that could provide shallow hydrothermal flow: outflow from the hot spring system northwest of the City, and outflow from a blind system further east following the regional hydraulic gradient. Maximum temperatures at depth for the two fluid types as estimated by multicomponent geothermometry are ~180°C for the hot spring system and ~150°C east of the shallow temperature anomaly. The drilling of four temperature gradient wells (GEO#1 -- GEO#4) within and near the shallow temperature anomaly failed to encounter a useful resource, but other shallow prospects and deeper resource prospects remain untested.
- Published
- 2018
3. Age-dependent gene expression of Calliphora vicina pupae (Diptera: Calliphoridae) at constant and fluctuating temperatures
- Author
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Hartmann, K., Herrmann, E., Amendt, J., Verhoff, M. A., and Zehner, R.
- Published
- 2021
- Full Text
- View/download PDF
4. Gendoping und molekulares Doping
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Diel, P. and Zehner, R.
- Published
- 2021
- Full Text
- View/download PDF
5. How should living entomological samples be stored?
- Author
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Bugelli, V., Campobasso, C. P., Zehner, R., and Amendt, J.
- Published
- 2019
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6. De novo transcriptome analysis and highly sensitive digital gene expression profiling of Calliphora vicina (Diptera: Calliphoridae) pupae using MACE (Massive Analysis of cDNA Ends)
- Author
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Zajac, B.K., Amendt, J., Horres, R., Verhoff, M.A., and Zehner, R.
- Published
- 2015
- Full Text
- View/download PDF
7. Leichenschau und Leichenöffnung in den Zeiten von Ebola: Medizinische und rechtliche Aspekte
- Author
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Parzeller, M., Wicker, S., Rabenau, H.F., Zehner, R., Kettner, M., and Verhoff, M.A.
- Published
- 2015
- Full Text
- View/download PDF
8. Gendoping und molekulares Doping
- Author
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Diel, P., primary and Zehner, R., additional
- Published
- 2020
- Full Text
- View/download PDF
9. Geologic maps of the eastern Alaska Range, Alaska (44 quadrangles, 1:63,360 scale), with descriptions and interpretations of map units
- Author
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Nokleberg, W. J., primary, Aleinikoff, J. N., additional, Bond, G. C., additional, Ferrians, O. J., additional, Herzon, P. L., additional, Lange, I. M., additional, Miyaoka, R. T., additional, Richter, D. H., additional, Schwab, C. E., additional, Silva, S. R., additional, Smith, T. E., additional, and Zehner, R. E., additional
- Published
- 2015
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10. A molecular, morphological, and physiological comparison of English and German populations of Calliphora vicina (Diptera: Calliphoridae).
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Limsopatham, K, Hall, MJR, Zehner, R, Zajac, BK, Verhoff, MA, Sontigun, N, Sukontason, K, Sukontason, KL, Amendt, J, Limsopatham, K, Hall, MJR, Zehner, R, Zajac, BK, Verhoff, MA, Sontigun, N, Sukontason, K, Sukontason, KL, and Amendt, J
- Abstract
The bluebottle blow fly Calliphora vicina is a common species distributed throughout Europe that can play an important role as forensic evidence in crime investigations. Developmental rates of C. vicina from distinct populations from Germany and England were compared under different temperature regimes to explore the use of growth data from different geographical regions for local case work. Wing morphometrics and molecular analysis between these populations were also studied as indicators for biological differences. One colony each of German and English C. vicina were cultured at the Institute of Legal Medicine in Frankfurt, Germany. Three different temperature regimes were applied, two constant (16°C & 25°C) and one variable (17-26°C, room temperature = RT). At seven time points (600, 850, 1200, 1450, 1800, 2050, and 2400 accumulated degree hours), larval lengths were measured; additionally, the durations of the post feeding stage and intrapuparial metamorphosis were recorded. For the morphometric and molecular study, 184 females and 133 males from each C. vicina population (Germany n = 3, England n = 4) were sampled. Right wings were measured based on 19 landmarks and analyzed using canonical variates analysis and discriminant function analysis. DNA was isolated from three legs per specimen (n = 61) using 5% chelex. A 784 bp long fragment of the mitochondrial cytochrome b gene was sequenced; sequences were aligned and phylogenetically analyzed. Similar larval growth rates of C. vicina were found from different geographic populations at different temperatures during the major part of development. Nevertheless, because minor differences were found a wider range of temperatures and sampling more time points should be analyzed to obtain more information relevant for forensic case work. Wing shape variation showed a difference between the German and English populations (P<0.0001). However, separation between the seven German and English populations at the smaller geog
- Published
- 2018
11. Leichenschau und Leichenöffnung in den Zeiten von Ebola
- Author
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Parzeller, M., primary, Wicker, S., additional, Rabenau, H.F., additional, Zehner, R., additional, Kettner, M., additional, and Verhoff, M.A., additional
- Published
- 2014
- Full Text
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12. How should living entomological samples be stored?
- Author
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V Bugelli, Carlo Pietro Campobasso, Jens Amendt, Richard Zehner, Bugelli, V, Campobasso, Cp, Zehner, R, and Amendt, J
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Forensic Entomology ,Calliphora vicina ,Blow fly ,Biology ,01 natural sciences ,Lucilia ,Pathology and Forensic Medicine ,Specimen Handling ,Toxicology ,03 medical and health sciences ,0302 clinical medicine ,Food supply ,Animals ,030216 legal & forensic medicine ,Forensic entomology ,Larva ,Oxygen supply ,Diptera ,fungi ,010401 analytical chemistry ,Temperature ,biology.organism_classification ,Forensic Entomology, sampling, storage, Calliphora vicina, Lucilia sericata ,0104 chemical sciences ,Oxygen ,Food ,Instar - Abstract
Sampling and storing insect evidence alive are important tasks in forensic entomology as it can impact survival and growth rates. To investigate the effect of cooling and storing of insect evidence before its arrival in the laboratory, samples of all three larval stages of the blow fly species Lucilia sericata and Calliphora vicina were analyzed. A first group was stored at room temperature and a second one in a refrigerator (~ 5 °C) for 16 h, all without air, supply of food, and sawdust. Afterwards, they were kept at 6–8 °C in a Styrofoam box for 8 h, simulating a transport situation. Mortality rate (MR) was calculated and 25% of the surviving larvae were killed and measured to check for interim growth. The remaining alive specimens were reared at 25 °C until adult’s eclosion for estimating a possible storage impact on survival during later development. The results were then compared with a control which was not temporarily stored and chilled but left feeding in boxes with an air-permeable lid on food substrate at 25 °C. A 24-h temporary storage stopped the larval growth in comparison with the control especially in early larval stages in both species. A high MR of up to 100% for third instar (L3) larvae stored both at room temperature and in a cold environment without air supply was found. Oxygen supply can reduce significantly the MR at least for L3 larvae of L. sericata. Findings provide scientific evidence for the recommendation to store larval samples at cold temperatures with both oxygen and food supply. The high MR for samples of the last larval stage clearly shows the need for a fast delivery after sampling and a more sophisticated storage procedure like, e.g., providing air supply. Storing live samples at room temperature without air access should be avoided.
- Published
- 2018
13. The applicability of forensic time since death estimation methods for buried bodies in advanced decomposition stages
- Author
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Angela Zissler, Bianca Ehrenfellner, Maurice C. G. Aalders, Janine Geißenberger, Joseph P. Receveur, Carlo Pietro Campobasso, Jens Amendt, Lena Lutz, Katharina Helm, Roelof-Jan Oostra, Vilma Pinchi, Fabio Monticelli, M. Eric Benbow, Richard Zehner, Christian Staufer, Stefan Pittner, Valentina Bugelli, Peter Steinbacher, Supramolecular Separations (HIMS, FNWI), Medical Biology, ACS - Amsterdam Cardiovascular Sciences, ARD - Amsterdam Reproduction and Development, Biomedical Engineering and Physics, ANS - Brain Imaging, ACS - Microcirculation, APH - Personalized Medicine, APH - Methodology, Pittner, S, Bugelli, V, Benbow, Me, Ehrenfellner, B, Zissler, A, Campobasso, Cp, Oostra, R-J, Aalders, Mcg, Zehner, R, Lutz, L, Monticelli, Fc, Staufer, C, Helm, K, Pinchi, V, Receveur, Jp, Geissenberger, J, Steinbacher, P, and Amendt, J
- Subjects
Time since death ,Insecta ,Taphonomy ,Burial ,Physiology ,Muscle Proteins ,Biochemistry ,Body Temperature ,Medicine and Health Sciences ,Forensic Pathology ,Multidisciplinary ,Microbiota ,Chemical Reactions ,Eukaryota ,Genomics ,Clinical Laboratory Sciences ,Death ,Insects ,Chemistry ,Physiological Parameters ,Medical Microbiology ,Models, Animal ,Physical Sciences ,Medicine ,Anatomy ,Cartography ,Research Article ,Arthropoda ,post-mortem interval, decomposition, forensic entomology, microbiome, skeletal muscle protein degradation, buried bodies ,Science ,Exhumation ,Microbial Genomics ,Biology ,Research initiative ,Microbiology ,Postmortem Changes ,Diagnostic Medicine ,Genetics ,Animals ,Humans ,Muscle, Skeletal ,Forensics ,Decomposition ,Organisms ,Biology and Life Sciences ,Proteins ,Forensic Medicine ,Invertebrates ,Pmi estimation ,Ears ,Proteolysis ,Microbiome ,Estimation methods ,Zoology ,Entomology ,Head - Abstract
Estimation of the postmortem interval in advanced postmortem stages is a challenging task. Although there are several approaches available for addressing postmortem changes of a (human) body or its environment (ecologically and/or biochemically), most are restricted to specific timeframes and/or individual and environmental conditions. It is well known, for instance, that buried bodies decompose in a remarkably different manner than on the ground surface. However, data on how established methods for PMI estimation perform under these conditions are scarce. It is important to understand whether and how postmortem changes are affected under burial conditions, if corrective factors could be conceived, or if methods have to be excluded for respective cases. We present the first multi-methodological assessment of human postmortem decomposition carried out on buried body donors in Europe, at the Amsterdam Research Initiative for Sub-surface Taphonomy and Anthropology (ARISTA) in the Netherlands. We used a multidisciplinary approach to investigate postmortem changes of morphology, skeletal muscle protein decomposition, presence of insects and other necrophilous animals as well as microbial communities (i.e., microbiomes) from August to November 2018 associated with two complete body exhumations and eight partial exhumations. Our results clearly display the current possibilities and limitations of methods for PMI estimation in buried remains and provide a baseline for future research and application.
- Published
- 2020
14. Tendons and table salt: A recipe to preserve human DNA.
- Author
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Birne VL, Birngruber CG, Vennemann M, Bauer H, Verhoff MA, Quezada Esparza G, Holz F, and Zehner R
- Abstract
For disaster victim identification, hundreds of samples of human remains have to be extracted from human bodies rapidly for later DNA analysis, often in situation with high humidity, high temperature and no access to cooling facilities. Genetic typing of these samples may be challenging due to degradation of DNA. Until today, bone and teeth are the preferred biological matrix for genetic identification of decomposed human remains. However, processing these samples is time and cost consuming. To address the challenges associated with workload, finances, and sample preservation in the genetic identification of unknown dead bodies, we tested 44 hand and foot tendons from deceased with advanced post mortem changes as alternative DNA material. In addition, we examined commercially available table salt as potential preservation method with 10 tendons over a period of 12 months. The parameters external appearance, DNA quantity and quality have been analysed. Overall, 39 of 44 tendons examined yielded valuable DNA profiles with at least ten autosomal STR loci. Storage in table salt not only increased DNA yield but also resulted in high quality STR profiles of the preserved tendons throughout the study period of 12 months compared to storage without salt. According to the results of this study, we recommend hand and foot tendons as alternative DNA material from bodies with advanced post mortem changes. We particularly recommend commercially available table salt as a storage medium for the preservation of DNA samples. Under field conditions without cooling facilities and the need to store samples prior to DNA analysis table salt is a good storage medium: it preserves DNA and is easily available., Competing Interests: Declaration of Competing Interest The authors declare they have no conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
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15. Establishment of a multiplex PCR-CE assay for the simultaneous and rapid analysis of age markers for Calliphora vicina pupae.
- Author
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Hartmann K, Bamberg M, Seum S, Amendt J, Verhoff MA, and Zehner R
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- Animals, Pupa, Multiplex Polymerase Chain Reaction, Larva, Calliphoridae genetics, Diptera genetics
- Abstract
Insects, especially blow flies, are forensically relevant to determine the minimal postmortem interval (PMI
min ), based on the fact that they are usually the first colonisers of a body. By estimating the age of immature blow flies, interferences can be made about the time since death. Whilst morphological parameters are valuable for age estimation of blow fly larvae, gene expression profiling is more applicable for blow fly pupae. Here, the age-dependent changes in the gene expression levels during the development are analysed. 28 temperature-independent markers have already been described for the age estimation of pupae of the forensically important blow fly Calliphora vicina and are analysed by RT-qPCR. To allow simultaneous analysis of these age markers, a multiplex assay was developed in the present study. After reverse transcription, the markers are analysed simultaneously in an endpoint PCR and subsequently separated by capillary electrophoresis (CE). This method is highly attractive due to its quick and easy procedure and interpretation. The present age prediction tool was adapted and validated. The multiplex PCR assay reproduced the same expression profiles as the RT-qPCR assay based on the same markers. The statistical evaluation shows that the new assay has a lower precision but a better trueness for age determination compared to the RT-qPCR assay. Since the new assay is also qualified to estimate the age of C. vicina pupae and is practical, cost-effective and, even more importantly, time-saving, it is attractive for use in forensic casework., (© 2023. The Author(s).)- Published
- 2024
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16. Identification of novel antiviral drug candidates using an optimized SARS-CoV-2 phenotypic screening platform.
- Author
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Bojkova D, Reus P, Panosch L, Bechtel M, Rothenburger T, Kandler JD, Pfeiffer A, Wagner JUG, Shumliakivska M, Dimmeler S, Olmer R, Martin U, Vondran FWR, Toptan T, Rothweiler F, Zehner R, Rabenau HF, Osman KL, Pullan ST, Carroll MW, Stack R, Ciesek S, Wass MN, Michaelis M, and Cinatl J Jr
- Abstract
Reliable, easy-to-handle phenotypic screening platforms are needed for the identification of anti-SARS-CoV-2 compounds. Here, we present caspase 3/7 activity as a readout for monitoring the replication of SARS-CoV-2 isolates from different variants, including a remdesivir-resistant strain, and of other coronaviruses in numerous cell culture models, independently of cytopathogenic effect formation. Compared to other models, the Caco-2 subline Caco-2-F03 displayed superior performance. It possesses a stable SARS-CoV-2 susceptibility phenotype and does not produce false-positive hits due to drug-induced phospholipidosis. A proof-of-concept screen of 1,796 kinase inhibitors identified known and novel antiviral drug candidates including inhibitors of phosphoglycerate dehydrogenase (PHGDH), CDC like kinase 1 (CLK-1), and colony stimulating factor 1 receptor (CSF1R). The activity of the PHGDH inhibitor NCT-503 was further increased in combination with the hexokinase II (HK2) inhibitor 2-deoxy-D-glucose, which is in clinical development for COVID-19. In conclusion, caspase 3/7 activity detection in SARS-CoV-2-infected Caco-2-F03 cells provides a simple phenotypic high-throughput screening platform for SARS-CoV-2 drug candidates that reduces false-positive hits., Competing Interests: The authors declare no competing interests., (© 2023 The Authors.)
- Published
- 2023
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17. It is all about the insects: a retrospective on 20 years of forensic entomology highlights the importance of insects in legal investigations.
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Lutz L, Zehner R, Verhoff MA, Bratzke H, and Amendt J
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- Animals, Cadaver, Humans, Retrospective Studies, Forensic Entomology, Insecta
- Abstract
This study highlights the importance of insect evidence by evaluating 949 insect-associated cases, including 139 entomological reports, from 2001 to 2019 at the Institute of Legal Medicine Frankfurt/Germany. With a high number of cases in the summer months and a low number in the colder season, 78.5% of the bodies were found indoors, regardless of year or month. In more than 80% of the cases, where PMI information was available (n = 704), the presumed PMI ranged from 1 to 21 days, a period during which entomological evidence can provide a day-specific estimate of PMI
min . In cases where insects have been identified to species level (n = 279), most bodies were infested by one or two species with a maximum of 10 different species. Overall, a total of 55 insect species were found. Information on biology, activity and distribution of the most abundant taxa is given and applied for 5 case histories estimating different PMImin s of up to over 6 months. Despite proved importance and scientific development of forensic entomology, insects are still rarely considered as a tool in forensic case work. The main reasons are a lack of awareness and (too) late involvement of a forensic entomologist. Our work shows that forensic entomology is an independent discipline that requires specialist expertise., (© 2021. The Author(s).)- Published
- 2021
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18. Influence of storage on larval length and age determination of the forensically important blow fly Lucilia sericata (Diptera: Calliphoridae).
- Author
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Matthes K, Zehner R, and Amendt J
- Subjects
- Animals, Calliphoridae, Ethanol, Humans, Larva, Diptera, Forensic Entomology
- Abstract
One of the main tasks in forensic entomology is the determination of the minimum post-mortem interval (PMI
min ) based on the age of the juvenile insects feeding and developing on the dead body. An important task is to store the evidence appropriately so that the evaluation and expert report can be used in court. However, existing recommendations can be contradictory or lacking scientific validation, e.g. by proposing various preservation liquids without knowing whether and to what extent the period of storage in such a liquid has an effect on the length of the preserved larvae. Storage time can be an issue since, due to technical and procedural circumstances, killed larvae may be stored for hours, days, weeks or even longer prior length measurement. A changed body length would have consequences for the entomological report, as the age of the larvae is usually derived from their length. This study investigates the effect of four differently concentrated ethanol solutions (70%, 80%, 90% and 96%) during a storage period of up to 196 days on the body length of stored larvae of the forensically important blow fly species L. sericata (Diptera: Calliphoridae). Larvae of different ages (24 h, 48 h and 72 h after hatching) were killed by immersion in hot, non-boiling water (≥80 °C) for at least 30 s. Their lengths were measured immediately. Subsequently samples were stored in ethanol of appropriate concentration at room temperature (approx. 22 °C). Further length measurements were made at 16 different storage intervals between 1 and 196 days. Many specimens showed a length decrease for most storage conditions and all larval ages. However, there was a tendency for 48 h- and 72 h-old larvae to increase in length after the first days of storage of up to 1.1 mm which may lead to an erroneous overestimation of the PMImin using this kind of specimens. All changes in length within each cohort over total time were in the range of +7% to -9.1%. Significant differences in length changes within the first days of storage were found mainly in larvae stored in 70%- and 80%-ethanol, but larvae stored in 90%- and 96%-ethanol showed first significant differences on day 56 at the earliest. Our results lead to the recommendation that the measurements of fly larvae samples should be taken immediately after killing and before storage to avoid any effects. Ethanol ≥90% should be used for storage., (Copyright © 2021 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.)- Published
- 2021
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19. Comparison of Updated Methods for Legionella Detection in Environmental Water Samples.
- Author
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Toplitsch D, Platzer S, Zehner R, Maitz S, Mascher F, and Kittinger C
- Subjects
- Humans, Water, Water Microbiology, Legionella genetics, Legionella pneumophila genetics, Legionellosis diagnosis
- Abstract
The difficulty of cultivation of Legionella spp. from water samples remains a strenuous task even for experienced laboratories. The long incubation periods for Legionellae make isolation difficult. In addition, the water samples themselves are often contaminated with accompanying microbial flora, and therefore require complex cultivation methods from diagnostic laboratories. In addition to the recent update of the standard culture method ISO 11731:2017, new strategies such as quantitative PCR (qPCR) are often discussed as alternatives or additions to conventional Legionella culture approaches. In this study, we compared ISO 11731:2017 with qPCR assays targeting Legionella spp., Legionella pneumophila , and Legionella pneumophila serogroup 1. In samples with a high burden of accompanying microbial flora, qPCR shows an excellent negative predictive value for Legionella pneumophila , thus making qPCR an excellent tool for pre-selection of negative samples prior to work-intensive culture methods. This and its low limit of detection make qPCR a diagnostic asset in Legionellosis outbreak investigations, where quick-risk assessments are essential, and are a useful method for monitoring risk sites.
- Published
- 2021
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20. The applicability of forensic time since death estimation methods for buried bodies in advanced decomposition stages.
- Author
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Pittner S, Bugelli V, Benbow ME, Ehrenfellner B, Zissler A, Campobasso CP, Oostra RJ, Aalders MCG, Zehner R, Lutz L, Monticelli FC, Staufer C, Helm K, Pinchi V, Receveur JP, Geißenberger J, Steinbacher P, and Amendt J
- Subjects
- Animals, Burial, Death, Exhumation, Humans, Insecta physiology, Microbiota, Models, Animal, Postmortem Changes, Forensic Medicine methods, Forensic Pathology methods, Muscle, Skeletal chemistry, Proteolysis
- Abstract
Estimation of the postmortem interval in advanced postmortem stages is a challenging task. Although there are several approaches available for addressing postmortem changes of a (human) body or its environment (ecologically and/or biochemically), most are restricted to specific timeframes and/or individual and environmental conditions. It is well known, for instance, that buried bodies decompose in a remarkably different manner than on the ground surface. However, data on how established methods for PMI estimation perform under these conditions are scarce. It is important to understand whether and how postmortem changes are affected under burial conditions, if corrective factors could be conceived, or if methods have to be excluded for respective cases. We present the first multi-methodological assessment of human postmortem decomposition carried out on buried body donors in Europe, at the Amsterdam Research Initiative for Sub-surface Taphonomy and Anthropology (ARISTA) in the Netherlands. We used a multidisciplinary approach to investigate postmortem changes of morphology, skeletal muscle protein decomposition, presence of insects and other necrophilous animals as well as microbial communities (i.e., microbiomes) from August to November 2018 associated with two complete body exhumations and eight partial exhumations. Our results clearly display the current possibilities and limitations of methods for PMI estimation in buried remains and provide a baseline for future research and application., Competing Interests: The authors declare that there are no competing interests.
- Published
- 2020
- Full Text
- View/download PDF
21. Age determination of the adult blow fly Lucilia sericata (Diptera: Calliphoridae) through quantitative pteridine fluorescence analysis.
- Author
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Estévez Dimitrov R, Amendt J, Rothweiler F, and Zehner R
- Subjects
- Animals, Forensic Entomology methods, Sex Factors, Aging, Calliphoridae growth & development, Eye metabolism, Pteridines metabolism, Spectrometry, Fluorescence
- Abstract
Determination of a minimal postmortem interval via age estimation of necrophagous diptera has been restricted to the juvenile stages and the time until emergence of the adult fly, i.e. up until 2-6 weeks depending on species and temperature. Age estimation of adult flies could extend this period by adding the age of the fly to the time needed for complete development. In this context pteridines are promising metabolites, as they accumulate in the eyes of flies with increasing age. We studied adults of the blow fly Lucilia sericata at constant temperatures of 16 °C and 25 °C up to an age of 25 days and estimated their pteridine levels by fluorescence spectroscopy. Age was given in accumulated degree days (ADD) across temperatures. Additionally, a mock case was set up to test the applicability of the method. Pteridine increases logarithmically with increasing ADD, but after 70-80 ADD the increase slows down and the curve approaches a maximum. Sex had a significant impact (p < 4.09 × 10
-6 ) on pteridine fluorescence level, while body-size and head-width did not. The mock case demonstrated that a slight overestimation of the real age (in ADD) only occurred in two out of 30 samples. Age determination of L. sericata on the basis of pteridine levels seems to be limited to an age of about 70 ADD, but depending on the ambient temperature this could cover an extra amount of time of about 5-7 days after completion of the metamorphosis.- Published
- 2020
- Full Text
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22. Brother-brother or father-son? How a dropout of AmelX may facilitate the elucidation of a familial relationship.
- Author
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Zajac BK, Scheiper S, Zehner R, Jenewein T, and Weissenberger M
- Subjects
- DNA Primers, Fathers, Humans, Male, Microsatellite Repeats, Pakistan ethnology, Sequence Analysis, DNA, Siblings, Alleles, Amelogenin genetics, DNA isolation & purification, Forensic Genetics
- Published
- 2020
- Full Text
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23. Revisited - Failure of tetrodotoxin to protect red-spotted newts, Notophthalmus viridescens, from endoparasites.
- Author
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Mebs D, Yotsu-Yamashita M, Hartmann K, Elbert C, Zehner R, and Toennes SW
- Subjects
- Animals, Notophthalmus viridescens physiology, Pennsylvania, Protective Agents, Salamandridae, Trematoda, Trematode Infections drug therapy, Antiplatyhelmintic Agents therapeutic use, Notophthalmus viridescens parasitology, Tetrodotoxin therapeutic use, Trematode Infections veterinary
- Abstract
Red-spotted newts, Notophthalmus viridescens, contain tetrodotoxin (TTX) and its analogue 6-epiTTX in variable concentrations. In a follow-up study, newts were sampled from a pond in Pennsylvania, USA, in 2010, 2014, and 2018. Their toxin levels were assayed by liquid-chromatography-fluorescence detection (LC-FLD), and assessment of their infection with endoparasites such as nematodes and helminths was performed by histological examination of internal organs. In the 2010 and 2014 samples, average prevalence of parasite infection was 53 and 60%, respectively, but reached 100% in the 2018 sample, where metacercaria stages of the digenean trematode genus Australapatemon/Apatemon (family: Strigeidae) were predominant causing severe tissue damage in liver and kidney. Mean values of TTX and 6-epiTTX were not significantly different in parasitized or parasite-free newts over the study period, confirming previous findings that host toxicity and parasite load are not negatively correlated. Whereas the role of TTX in defence against predators is undisputed, its efficacy to prevent parasitic infections is less obvious. Toxin-resistance of various metazoan parasites may promote their widespread occurrence in poisonous newts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
24. Intact-Cell MALDI-ToF Mass Spectrometry for the Authentication of Drug-Adapted Cancer Cell Lines.
- Author
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Povey JF, Saintas E, Aderemi AV, Rothweiler F, Zehner R, Dirks WG, Cinatl J Jr, Racher AJ, Wass MN, Smales CM, and Michaelis M
- Subjects
- Animals, Antineoplastic Agents pharmacology, Cell Line, Tumor, Cisplatin pharmacology, Humans, Vincristine pharmacology, Cell Line Authentication methods, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods
- Abstract
The use of cell lines in research can be affected by cell line misidentification. Short tandem repeat (STR) analysis is an effective method, and the gold standard, for the identification of the genetic origin of a cell line, but methods that allow the discrimination between cell lines of the same genetic origin are lacking. Here, we use intact cell MALDI-ToF mass spectrometry analysis, routinely used for the identification of bacteria in clinical diagnostic procedures, for the authentication of a set of cell lines consisting of three parental neuroblastoma cell lines (IMR-5, IMR-32 and UKF-NB-3) and eleven drug-adapted sublines. Principal component analysis (PCA) of intact-cell MALDI-ToF mass spectrometry data revealed clear differences between most, but not all, of the investigated cell lines. Mass spectrometry whole-cell fingerprints enabled the separation of IMR-32 and its clonal subline IMR-5. Sublines that had been adapted to closely related drugs, for example, the cisplatin- and oxaliplatin-resistant UKF-NB-3 sublines and the vincristine- and vinblastine-adapted IMR-5 sublines, also displayed clearly distinctive patterns. In conclusion, intact whole-cell MALDI-ToF mass spectrometry has the potential to be further developed into an authentication method for mammalian cells of a common genetic origin.
- Published
- 2019
- Full Text
- View/download PDF
25. A molecular, morphological, and physiological comparison of English and German populations of Calliphora vicina (Diptera: Calliphoridae).
- Author
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Limsopatham K, Hall MJR, Zehner R, Zajac BK, Verhoff MA, Sontigun N, Sukontason K, Sukontason KL, and Amendt J
- Subjects
- Animals, Diptera genetics, England, Germany, Organ Size, Phylogeny, Wings, Animal anatomy & histology, Diptera anatomy & histology, Diptera physiology
- Abstract
The bluebottle blow fly Calliphora vicina is a common species distributed throughout Europe that can play an important role as forensic evidence in crime investigations. Developmental rates of C. vicina from distinct populations from Germany and England were compared under different temperature regimes to explore the use of growth data from different geographical regions for local case work. Wing morphometrics and molecular analysis between these populations were also studied as indicators for biological differences. One colony each of German and English C. vicina were cultured at the Institute of Legal Medicine in Frankfurt, Germany. Three different temperature regimes were applied, two constant (16°C & 25°C) and one variable (17-26°C, room temperature = RT). At seven time points (600, 850, 1200, 1450, 1800, 2050, and 2400 accumulated degree hours), larval lengths were measured; additionally, the durations of the post feeding stage and intrapuparial metamorphosis were recorded. For the morphometric and molecular study, 184 females and 133 males from each C. vicina population (Germany n = 3, England n = 4) were sampled. Right wings were measured based on 19 landmarks and analyzed using canonical variates analysis and discriminant function analysis. DNA was isolated from three legs per specimen (n = 61) using 5% chelex. A 784 bp long fragment of the mitochondrial cytochrome b gene was sequenced; sequences were aligned and phylogenetically analyzed. Similar larval growth rates of C. vicina were found from different geographic populations at different temperatures during the major part of development. Nevertheless, because minor differences were found a wider range of temperatures and sampling more time points should be analyzed to obtain more information relevant for forensic case work. Wing shape variation showed a difference between the German and English populations (P<0.0001). However, separation between the seven German and English populations at the smaller geographic scale remained ambiguous. Molecular phylogenetic analysis by maximum likelihood method could not unambiguously separate the different geographic populations at a national (Germany vs England) or local level., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
- Full Text
- View/download PDF
26. Molecular Analysis of Forensically Important Blow Flies in Thailand.
- Author
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Sontigun N, Sukontason KL, Amendt J, Zajac BK, Zehner R, Sukontason K, Chareonviriyaphap T, and Wannasan A
- Abstract
Blow flies are the first insect group to colonize on a dead body and thus correct species identification is a crucial step in forensic investigations for estimating the minimum postmortem interval, as developmental times are species-specific. Due to the difficulty of traditional morphology-based identification such as the morphological similarity of closely related species and uncovered taxonomic keys for all developmental stages, DNA-based identification has been increasing in interest, especially in high biodiversity areas such as Thailand. In this study, the effectiveness of long mitochondrial cytochrome c oxidase subunit I and II ( COI and COII ) sequences (1247 and 635 bp, respectively) in identifying 16 species of forensically relevant blow flies in Thailand ( Chrysomya bezziana , Chrysomya chani , Chrysomya megacephala , Chrysomya nigripes , Chrysomya pinguis , Chrysomya rufifacies , Chrysomya thanomthini , Chrysomya villeneuvi , Lucilia cuprina , Lucilia papuensis , Lucilia porphyrina , Lucilia sinensis , Hemipyrellia ligurriens , Hemipyrellia pulchra , Hypopygiopsis infumata , and Hypopygiopsis tumrasvini ) was assessed using distance-based (Kimura two-parameter distances based on Best Match, Best Close Match, and All Species Barcodes criteria) and tree-based (grouping taxa by sequence similarity in the neighbor-joining tree) methods. Analyses of the obtained sequence data demonstrated that COI and COII genes were effective markers for accurate species identification of the Thai blow flies. This study has not only demonstrated the genetic diversity of Thai blow flies, but also provided a reliable DNA reference database for further use in forensic entomology within the country and other regions where these species exist.
- Published
- 2018
- Full Text
- View/download PDF
27. Kit-dependent discrepancy in D16S539 and general considerations for database matches.
- Author
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Zajac BK, Zehner R, Scheiper S, and Weissenberger M
- Subjects
- Alleles, Databases, Genetic, Female, Humans, Male, Polymerase Chain Reaction, Sequence Analysis, DNA, Sequence Deletion, DNA Fingerprinting instrumentation, Microsatellite Repeats, Paternity
- Abstract
Throughout the last decade more companies have been offering multiplex PCR kits for forensic STR typing. As a consequence, it has been demonstrated, that an observed genotype may unexpectedly vary at a single locus when different STR kits have been used. Analysing STR profiles which have to be entered in a national database, unknown or undetected primer binding site mutations, insertions or deletions within the flanking region of STR loci may hinder matches and therefore have far-reaching consequences. The current study is a further example indicating that sequence variations in flanking regions are a common problem within STR typing which should not be underestimated. A deletion of 16 nucleotides close to the primer binding site downstream of the repeat sequence resulted in deviant genotypes at the D16S539 locus according to different STR kits used., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
28. Dating Pupae of the Blow Fly Calliphora vicina Robineau-Desvoidy 1830 (Diptera: Calliphoridae) for Post Mortem Interval-Estimation: Validation of Molecular Age Markers.
- Author
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Zajac BK, Amendt J, Verhoff MA, and Zehner R
- Abstract
Determining the age of juvenile blow flies is one of the key tasks of forensic entomology when providing evidence for the minimum post mortem interval. While the age determination of blow fly larvae is well established using morphological parameters, the current study focuses on molecular methods for estimating the age of blow flies during the metamorphosis in the pupal stage, which lasts about half the total juvenile development. It has already been demonstrated in several studies that the intraspecific variance in expression of so far used genes in blow flies is often too high to assign a certain expression level to a distinct age, leading to an inaccurate prediction. To overcome this problem, we previously identified new markers, which show a very sharp age dependent expression course during pupal development of the forensically-important blow fly Calliphora vicina Robineau-Desvoidy 1830 (Diptera: Calliphoridae) by analyzing massive parallel sequencing (MPS) generated transcriptome data. We initially designed and validated two quantitative polymerase chain reaction (qPCR) assays for each of 15 defined pupal ages representing a daily progress during the total pupal development if grown at 17 °C. We also investigated whether the performance of these assays is affected by the ambient temperature, when rearing pupae of C. vicina at three different constant temperatures-namely 17 °C, 20 °C and 25 °C. A temperature dependency of the performance could not be observed, except for one marker. Hence, for each of the defined development landmarks, we can present gene expression profiles of one to two markers defining the mentioned progress in development., Competing Interests: The authors declare no conflict of interest.
- Published
- 2018
- Full Text
- View/download PDF
29. Wing morphometrics as a tool in species identification of forensically important blow flies of Thailand.
- Author
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Sontigun N, Sukontason KL, Zajac BK, Zehner R, Sukontason K, Wannasan A, and Amendt J
- Subjects
- Animals, Female, Male, Sex Characteristics, Species Specificity, Thailand, Diptera anatomy & histology, Diptera classification, Wings, Animal anatomy & histology
- Abstract
Background: Correct species identification of blow flies is a crucial step for understanding their biology, which can be used not only for designing fly control programs, but also to determine the minimum time since death. Identification techniques are usually based on morphological and molecular characters. However, the use of classical morphology requires experienced entomologists for correct identification; while molecular techniques rely on a sound laboratory expertise and remain ambiguous for certain taxa. Landmark-based geometric morphometric analysis of insect wings has been extensively applied in species identification. However, few wing morphometric analyses of blow fly species have been published., Methods: We applied a landmark-based geometric morphometric analysis of wings for species identification of 12 medically and forensically important blow fly species of Thailand. Nineteen landmarks of each right wing of 372 specimens were digitised. Variation in wing size and wing shape was analysed and evaluated for allometric effects. The latter confirmed the influence of size on the shape differences between species and sexes. Wing shape variation among genera and species were analysed using canonical variates analysis followed by a cross-validation test., Results: Wing size was not suitable for species discrimination, whereas wing shape can be a useful tool to separate taxa on both, genus and species level depending on the analysed taxa. It appeared to be highly reliable, especially for classifying Chrysomya species, but less robust for a species discrimination in the genera Lucilia and Hemipyrellia. Allometry did not affect species separation but had an impact on sexual shape dimorphism., Conclusions: A landmark-based geometric morphometric analysis of wings is a useful additional method for species discrimination. It is a simple, reliable and inexpensive method, but it can be time-consuming locating the landmarks for a large scale study and requires non-damaged wings for analysis.
- Published
- 2017
- Full Text
- View/download PDF
30. Quantitative pteridine fluorescence analysis: A possible age-grading technique for the adult stages of the blow fly Calliphora vicina (Diptera: Calliphoridae).
- Author
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Bernhardt V, Hannig L, Kinast R, Verhoff MA, Rothweiler F, Zehner R, and Amendt J
- Subjects
- Animals, Female, Fluorescence, Male, Aging, Diptera physiology, Entomology methods, Forensic Sciences methods, Pteridines analysis
- Abstract
Age estimation of adult flies could extend the possible window of time for calculating the minimal postmortem interval (PMI
min ) by means of entomological methods. Currently, this is done by estimating the time required by necrophagous Diptera to reach certain juvenile developmental landmarks, and the method only works until the end of metamorphosis and emergence of the adult fly. Particularly at indoor crime scenes, being able to estimate the age of trapped adult flies would be an important tool with which to extend the calculable PMI beyond the developmental period. Recently, several promising age-dependent morphological and physiological characteristics of adult insects have been investigated in medical and forensic entomology, but the results are still preliminary and restricted to a few species. We examined adults of the forensically relevant blow fly species Calliphora vicina and investigated the fluorescence levels of pteridine, a group of metabolites that accumulates in the eyes during aging. From Day 1 to Day 25 post-emergence, flies were kept at three different temperature regimes (20°C, 25°C, and fluctuating temperatures in the context of a field study) and 12:12 L:D. From Day 1 until Day 7, the fluorescence of pteridine was determined on a daily basis, and thereafter, every three days. The achieved fly age was multiplied with the relevant temperature and converted into accumulated degree-days (ADD). The fluorescence level of pteridine increased linear with increasing ADD (females: R2 =0.777; males: R2 =0.802). The difference between sexes was significant (p<0.001). Neither head weight nor temperature had an effect on pteridine fluorescence. Because the variation in pteridine fluorescence increased with increasing ADD, it seems favorable to combine several aging methods for more precise results. In context, we emphasize that different body parts of the same specimen can be used to analyze cuticular hydrocarbons (legs), pteridine fluorescence (head/eyes), and gonotrophic stage (female abdomen)., (Copyright © 2017 Elsevier Ltd. All rights reserved.)- Published
- 2017
- Full Text
- View/download PDF
31. Interdisciplinary teaching and training - A medicolegal specialty.
- Author
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Parzeller M, Amendt J, Zehner R, Toennes SW, Kettner M, Bratzke H, and Verhoff MA
- Subjects
- Germany, Humans, Curriculum, Forensic Medicine education, Interdisciplinary Communication, Intersectoral Collaboration, Models, Educational
- Abstract
The Frankfurt model is described to exemplify the teaching and training concepts implemented at the Institute of Legal Medicine in Frankfurt am Main up to 2015. The Frankfurt model describes a comprehensive, networked teaching system aiming at an interdisciplinary training. Interdisciplinarity is a domain of forensic medicine as a broadly diversified subject related to various scientific disciplines. The importance of the medicolegal triad (research, teaching, services) rooted in the university setting, on which the success of this interdisciplinary teaching and training concept is based, is illustrated. Sufficient funding is required to maintain this medicolegal triad, and the consequences of potential reductions due to fiscal reasons are outlined.
- Published
- 2017
32. Acquired resistance to oxaliplatin is not directly associated with increased resistance to DNA damage in SK-N-ASrOXALI4000, a newly established oxaliplatin-resistant sub-line of the neuroblastoma cell line SK-N-AS.
- Author
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Saintas E, Abrahams L, Ahmad GT, Ajakaiye AM, AlHumaidi AS, Ashmore-Harris C, Clark I, Dura UK, Fixmer CN, Ike-Morris C, Mato Prado M, Mccullough D, Mishra S, Schöler KM, Timur H, Williamson MD, Alatsatianos M, Bahsoun B, Blackburn E, Hogwood CE, Lithgow PE, Rowe M, Yiangou L, Rothweiler F, Cinatl J Jr, Zehner R, Baines AJ, Garrett MD, Gourlay CW, Griffin DK, Gullick WJ, Hargreaves E, Howard MJ, Lloyd DR, Rossman JS, Smales CM, Tsaousis AD, von der Haar T, Wass MN, and Michaelis M
- Subjects
- Antineoplastic Agents pharmacology, Carboplatin pharmacology, Cell Line, Tumor, Cisplatin pharmacology, DNA Repair genetics, Deoxycytidine analogs & derivatives, Deoxycytidine pharmacology, Doxorubicin pharmacology, Humans, In Situ Hybridization, Fluorescence, Neuroblastoma genetics, Neuroblastoma pathology, Oxaliplatin, Ploidies, Ultraviolet Rays, Gemcitabine, DNA Damage, Drug Resistance, Multiple genetics, Drug Resistance, Neoplasm genetics, Organoplatinum Compounds pharmacology
- Abstract
The formation of acquired drug resistance is a major reason for the failure of anti-cancer therapies after initial response. Here, we introduce a novel model of acquired oxaliplatin resistance, a sub-line of the non-MYCN-amplified neuroblastoma cell line SK-N-AS that was adapted to growth in the presence of 4000 ng/mL oxaliplatin (SK-N-ASrOXALI4000). SK-N-ASrOXALI4000 cells displayed enhanced chromosomal aberrations compared to SK-N-AS, as indicated by 24-chromosome fluorescence in situ hybridisation. Moreover, SK-N-ASrOXALI4000 cells were resistant not only to oxaliplatin but also to the two other commonly used anti-cancer platinum agents cisplatin and carboplatin. SK-N-ASrOXALI4000 cells exhibited a stable resistance phenotype that was not affected by culturing the cells for 10 weeks in the absence of oxaliplatin. Interestingly, SK-N-ASrOXALI4000 cells showed no cross resistance to gemcitabine and increased sensitivity to doxorubicin and UVC radiation, alternative treatments that like platinum drugs target DNA integrity. Notably, UVC-induced DNA damage is thought to be predominantly repaired by nucleotide excision repair and nucleotide excision repair has been described as the main oxaliplatin-induced DNA damage repair system. SK-N-ASrOXALI4000 cells were also more sensitive to lysis by influenza A virus, a candidate for oncolytic therapy, than SK-N-AS cells. In conclusion, we introduce a novel oxaliplatin resistance model. The oxaliplatin resistance mechanisms in SK-N-ASrOXALI4000 cells appear to be complex and not to directly depend on enhanced DNA repair capacity. Models of oxaliplatin resistance are of particular relevance since research on platinum drugs has so far predominantly focused on cisplatin and carboplatin., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2017
- Full Text
- View/download PDF
33. ,,Flora and fauna" in criminalistics - an analysis of the current use and relevance of non-human biological trace materials in criminal proceedings.
- Author
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Nahrmann J, Amnendt J, Zehner R, and Parzeller M
- Subjects
- Adult, Aged, Animal Fur, Animals, Cause of Death, Child Abuse legislation & jurisprudence, Diptera, Expert Testimony legislation & jurisprudence, Female, Germany, Humans, Infant, Infanticide legislation & jurisprudence, Insecta, Larva, Male, Postmortem Changes, Body Remains pathology, Forensic Medicine legislation & jurisprudence, Homicide legislation & jurisprudence, Organic Chemicals analysis, Plants
- Abstract
The analysis of biological, non-human trace specimens can contribute significantly to solving a criminal case. The present study searches the relevant German criminal, forensic, legal and biological literature, focusing on animal hairs, insects and plant fragments, and assesses the current opportunities of this special forensic branch and its acceptance and relevance for the evidence in court. It turns out that the analysis of these trace materials has an enormous range of potential applications which should not only be reflected in the forensic sciences, but also in the criminal trials. However, in the legal literature and legal annotations the topic of biological, non-human trace materials is addressed only sporadically. To derive the greatest practical benefit from the developments of forensic biology, the knowledge about the use of biological, non-human trace specimens should be promoted for the criminal proceedings. Investigators, judges, prosecutors and defense lawyers should be more thoroughly informed and become trained by forensic biologists.
- Published
- 2016
34. Application of DNA barcoding for identifying forensically relevant Diptera from northern Thailand.
- Author
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Zajac BK, Sontigun N, Wannasan A, Verhoff MA, Sukontason K, Amendt J, and Zehner R
- Subjects
- Animals, Autopsy methods, Entomology methods, Forensic Sciences methods, Polymerase Chain Reaction, Sequence Analysis, DNA, Thailand, DNA Barcoding, Taxonomic methods, Diptera classification, Diptera genetics, Electron Transport Complex IV genetics, RNA, Ribosomal, 28S genetics
- Abstract
In recent decades, forensic entomology has become a useful tool in criminal investigations all over the world. Species-specific identification of flies plays an important role in this field and is obligatory for accurate calculation of the post-mortem interval. However, not all important colonizers of a corpse can be identified by common morphological keys. Due to similar morphology and the lack of keys for some taxa, especially for immature stages, DNA barcoding has become more popular during the last recent years. This development is particularly important for countries like Thailand, in which forensic entomology is a newly developing research area and which faces several challenges such as a high biodiversity of fly species. The most commonly used barcoding region in forensic entomology, the mitochondrial cytochrome oxidase subunit 1 (coI) gene, as well as a 1000-bp-long region of the 28S nuclear rRNA gene, was used to analyze and establish the molecular barcodes of 13 different species of flies of forensic relevance in northern Thailand.
- Published
- 2016
- Full Text
- View/download PDF
35. Molecular identification and phylogenetic analysis of the forensically important family Piophilidae (Diptera) from different European locations.
- Author
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Zajac BK, Martin-Vega D, Feddern N, Fremdt H, e Castro CP, Szpila K, Reckel F, Schütt S, Verhoff MA, Amendt J, and Zehner R
- Subjects
- Animals, DNA Barcoding, Taxonomic methods, Entomology methods, Europe, Polymerase Chain Reaction, Sequence Analysis, DNA methods, Species Specificity, DNA, Mitochondrial genetics, Diptera genetics, Forensic Sciences, Phylogeny
- Abstract
Species identification plays an important role in forensic entomology and is mandatory for an accurate calculation of the minimum post-mortem interval. Many important Diptera and Coleoptera taxa of the cadaver community can already be identified by common barcoding approaches, i.e., by sequencing a 658bp region in the mitochondrial cytochrome c oxidase subunit I (coI) gene. Nevertheless, there is still a lack of reference barcodes for species, in particular, that can be found on cadavers at later decomposition stages. Flies of the family Piophilidae illustrate this gap of knowledge perfectly. Due to the fact that a reliable morphological identification key for the immature stages of this flies is still missing and the immature stages of many piophilids cannot be assigned to a certain species, there is need for additional tools to identify forensically relevant taxa. We collected adult piophilid specimens at 10 locations in five European countries: Spain (n=3 locations), Germany (n=3), Portugal (n=2), Poland (n=1) and Switzerland (n=1). Apart from the coI barcoding region, we additionally analyzed a 398bp long region of the nuclear elongation factor 1 alpha (ef1a) and subsequently established the molecular identifier for nine piophilid species. In addition, we present the molecular phylogeny of the examined taxa., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
36. Descriptive analyses of differentially expressed genes during larval development of Calliphora vicina (Diptera: Calliphoridae).
- Author
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Baqué M, Amendt J, Verhoff MA, and Zehner R
- Subjects
- Actins genetics, Animals, Drosophila Proteins genetics, HSP90 Heat-Shock Proteins genetics, Real-Time Polymerase Chain Reaction, Diptera genetics, Diptera growth & development, Gene Expression, Larva growth & development
- Abstract
The analysis of insect evidence is often used in death investigations as the development of necrophagous insect species can be used to determine a minimum post-mortem interval (PMImin). Usually, the PMImin estimations are based on the age estimation of larvae developed on the corpse. So far, age estimation mostly relies on length or weight measurement of the larvae. These measurements are then compared to species-specific reference growth data obtained from laboratory studies. However, length and weight do not always represent the best developmental markers to provide accurate and precise age estimates for PMImin calculation, especially for post-feeding third-instar larvae which decrease in size. Therefore, more growth markers are required to improve age estimation not only for post-feeding larvae but also for all larval stages. As the analysis of temporally regulated genes proved suitable for age prediction in blow fly pupae, we examined the gene expression patterns of six genes (15_2, 2014192, EcdR, AR, hsp90 and actin) during larval development of Calliphora vicina at three constant temperatures and analysed the effect of a combination of morphological and molecular age markers on statistical models of development. EcdR, AR and 15_2 showed reliable tendencies to classify the post-feeding stage more precisely, and inclusion of gene expression data in models of development improved the statistical fit of the model. Nevertheless, for depicting the first larval stages and for quantifying the onset of the post-feeding stage more accurately, results of this preliminary study should be supported by searching for more informative genes.
- Published
- 2015
- Full Text
- View/download PDF
37. Identification of flubendazole as potential anti-neuroblastoma compound in a large cell line screen.
- Author
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Michaelis M, Agha B, Rothweiler F, Löschmann N, Voges Y, Mittelbronn M, Starzetz T, Harter PN, Abhari BA, Fulda S, Westermann F, Riecken K, Spek S, Langer K, Wiese M, Dirks WG, Zehner R, Cinatl J, Wass MN, and Cinatl J Jr
- Subjects
- Animals, Apoptosis Regulatory Proteins antagonists & inhibitors, Apoptosis Regulatory Proteins genetics, Apoptosis Regulatory Proteins metabolism, Cell Line, Tumor, Chickens, Cyclin-Dependent Kinase Inhibitor p21 antagonists & inhibitors, Cyclin-Dependent Kinase Inhibitor p21 genetics, Cyclin-Dependent Kinase Inhibitor p21 metabolism, Humans, Imidazoles antagonists & inhibitors, Imidazoles metabolism, Mebendazole pharmacology, Neuroblastoma metabolism, Neuroblastoma pathology, Piperazines antagonists & inhibitors, Piperazines metabolism, Proto-Oncogene Proteins antagonists & inhibitors, Proto-Oncogene Proteins genetics, Proto-Oncogene Proteins metabolism, Proto-Oncogene Proteins c-mdm2 antagonists & inhibitors, Proto-Oncogene Proteins c-mdm2 metabolism, RNA Interference, RNA, Small Interfering metabolism, Signal Transduction drug effects, Tumor Suppressor Protein p53 antagonists & inhibitors, Tumor Suppressor Protein p53 genetics, Tumor Suppressor Protein p53 metabolism, bcl-2-Associated X Protein antagonists & inhibitors, bcl-2-Associated X Protein genetics, bcl-2-Associated X Protein metabolism, Antineoplastic Agents pharmacology, Apoptosis drug effects, Mebendazole analogs & derivatives
- Abstract
Flubendazole was shown to exert anti-leukaemia and anti-myeloma activity through inhibition of microtubule function. Here, flubendazole was tested for its effects on the viability of in total 461 cancer cell lines. Neuroblastoma was identified as highly flubendazole-sensitive cancer entity in a screen of 321 cell lines from 26 cancer entities. Flubendazole also reduced the viability of five primary neuroblastoma samples in nanomolar concentrations thought to be achievable in humans and inhibited vessel formation and neuroblastoma tumour growth in the chick chorioallantoic membrane assay. Resistance acquisition is a major problem in high-risk neuroblastoma. 119 cell lines from a panel of 140 neuroblastoma cell lines with acquired resistance to various anti-cancer drugs were sensitive to flubendazole in nanomolar concentrations. Tubulin-binding agent-resistant cell lines displayed the highest flubendazole IC50 and IC90 values but differences between drug classes did not reach statistical significance. Flubendazole induced p53-mediated apoptosis. The siRNA-mediated depletion of the p53 targets p21, BAX, or PUMA reduced the neuroblastoma cell sensitivity to flubendazole with PUMA depletion resulting in the most pronounced effects. The MDM2 inhibitor and p53 activator nutlin-3 increased flubendazole efficacy while RNAi-mediated p53-depletion reduced its activity. In conclusion, flubendazole represents a potential treatment option for neuroblastoma including therapy-refractory cells.
- Published
- 2015
- Full Text
- View/download PDF
38. Diapause-specific gene expression in Calliphora vicina (Diptera: Calliphoridae)--a useful diagnostic tool for forensic entomology.
- Author
-
Fremdt H, Amendt J, and Zehner R
- Subjects
- Animals, Base Sequence, Feeding Behavior, Forensic Pathology, Gene Expression, Heat-Shock Proteins genetics, Humans, Larva, Postmortem Changes, Real-Time Polymerase Chain Reaction, Diapause, Insect genetics, Diptera, Heat-Shock Proteins metabolism, Up-Regulation
- Abstract
Estimating the post mortem interval (PMImin) by age determination of blow fly larvae has been well-established for moderate temperatures. Low-temperature developmental data is only available sparsely and usually does not take overwintering strategies into account. The blow fly Calliphora vicina hibernates by diapausing in the third larval stage extending the duration of this developmental stage up to several weeks or even months. As the diagnosis of the diapause status is not possible by morphological characteristics, PMImin estimations might be biased during the cold season if only based on age determination of third instar larvae of C. vicina. Molecular markers were searched for which allows one to identify diapause in larvae. Expression analysis of 19 genes was performed in diapausing and non-diapausing larvae. Three genes encoding for heat shock proteins (hsp23, hsp24 and hsp70) were found to be up-regulated distinctly in diapausing larvae and at 1 day in non-diapausing larvae. If several larvae are subjected to an analysis, a high variance in the expression level of the gene encoding for the anterior fat body protein is a further marker for diapause. The present study proves the potential use of gene expression analysis as a suitable diagnosis tool for diapause in C. vicina.
- Published
- 2014
- Full Text
- View/download PDF
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