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1.
Nanotechnology ; 32(36)2021 Jun 18.
Article in English | MEDLINE | ID: mdl-34082414

ABSTRACT

An ordered, crack-free array of anatase TiO2nanotubes were prepared via anodization and annealing at 550 °C. Oxygen vacancies are known to improve photocatalytic activity in TiO2and were introduced using a facile low vacuum annealing. Stoichiometric and nonstoichiometric films were followed by a conformal Pt deposition at 250 °C using atomic layer deposition resulting in a current rectifying device, or Schottky diode. Here, we investigated the current-voltage effects of a post thermal treatment using 350 °C and 400 °C. This paper presents reproducible improvements in the charge transport behavior after a 350 °C post-fabrication annealing process. Oxygen vacancies resulted in the formation of a shunt resistance behavior of 105Ω and no overall performance improvements compared to stoichiometric films. Additionally, thermal treatments offered trap-based shifts from multiple trap distributions to a single trap distribution. This work hereby provides valuable experimental observations into understanding the effects of oxygen vacancies and effectively modifying the electronic properties of a conformal Pt/TiO2-xnanostructured junction using a facile post-thermal treatment.

2.
Appl Microbiol Biotechnol ; 102(2): 587-595, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29196787

ABSTRACT

Erythritol is a naturally abundant sweetener gaining more and more importance especially within the food industry. It is widely used as sweetener in calorie-reduced food, candies, or bakery products. In research focusing on sugar alternatives, erythritol is a key issue due to its, compared to other polyols, challenging production. It cannot be chemically synthesized in a commercially worthwhile way resulting in a switch to biotechnological production. In this area, research efforts have been made to improve concentration, productivity, and yield. This mini review will give an overview on the attempts to improve erythritol production as well as their development over time.


Subject(s)
Erythritol/biosynthesis , Sweetening Agents/metabolism , Bacteria/metabolism , Biotechnology , Food Industry , Yeasts/metabolism
3.
Appl Environ Microbiol ; 81(15): 5134-43, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26002900

ABSTRACT

Because of high diurnal water quality fluctuations in raw municipal wastewater, the use of proportional autosampling over a period of 24 h at municipal wastewater treatment plants (WWTPs) to evaluate carbon, nitrogen, and phosphorus removal has become a standard in many countries. Microbial removal or load estimation at municipal WWTPs, however, is still based on manually recovered grab samples. The goal of this study was to establish basic knowledge regarding the persistence of standard bacterial fecal indicators and Bacteroidetes genetic microbial source tracking markers in municipal wastewater in order to evaluate their suitability for automated sampling, as the potential lack of persistence is the main argument against such procedures. Raw and secondary treated wastewater of municipal origin from representative and well-characterized biological WWTPs without disinfection (organic carbon and nutrient removal) was investigated in microcosm experiments at 5 and 21°C with a total storage time of 32 h (including a 24-h autosampling component and an 8-h postsampling phase). Vegetative Escherichia coli and enterococci, as well as Clostridium perfringens spores, were selected as indicators for cultivation-based standard enumeration. Molecular analysis focused on total (AllBac) and human-associated genetic Bacteroidetes (BacHum-UCD, HF183 TaqMan) markers by using quantitative PCR, as well as 16S rRNA gene-based next-generation sequencing. The microbial parameters showed high persistence in both raw and treated wastewater at 5°C under the storage conditions used. Surprisingly, and in contrast to results obtained with treated wastewater, persistence of the microbial markers in raw wastewater was also high at 21°C. On the basis of our results, 24-h autosampling procedures with 5°C storage conditions can be recommended for the investigation of fecal indicators or Bacteroidetes genetic markers at municipal WWTPs. Such autosampling procedures will contribute to better understanding and monitoring of municipal WWTPs as sources of fecal pollution in water resources.


Subject(s)
Bacteria/classification , Bacteria/isolation & purification , Bacteriological Techniques/methods , DNA Fingerprinting/methods , Feces/microbiology , Wastewater/microbiology , Water Purification , Bacteria/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , High-Throughput Nucleotide Sequencing , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Temperature
4.
Water Sci Technol ; 72(11): 1962-72, 2015.
Article in English | MEDLINE | ID: mdl-26606090

ABSTRACT

The applicability of next generation DNA sequencing (NGS) methods for water quality assessment has so far not been broadly investigated. This study set out to evaluate the potential of an NGS-based approach in a complex catchment with importance for drinking water abstraction. In this multi-compartment investigation, total bacterial communities in water, faeces, soil, and sediment samples were investigated by 454 pyrosequencing of bacterial 16S rRNA gene amplicons to assess the capabilities of this NGS method for (i) the development and evaluation of environmental molecular diagnostics, (ii) direct screening of the bulk bacterial communities, and (iii) the detection of faecal pollution in water. Results indicate that NGS methods can highlight potential target populations for diagnostics and will prove useful for the evaluation of existing and the development of novel DNA-based detection methods in the field of water microbiology. The used approach allowed unveiling of dominant bacterial populations but failed to detect populations with low abundances such as faecal indicators in surface waters. In combination with metadata, NGS data will also allow the identification of drivers of bacterial community composition during water treatment and distribution, highlighting the power of this approach for monitoring of bacterial regrowth and contamination in technical systems.


Subject(s)
Bacteria/isolation & purification , DNA, Bacterial/genetics , Fresh Water/microbiology , High-Throughput Nucleotide Sequencing/methods , RNA, Ribosomal, 16S/genetics , Bacteria/classification , Bacteria/genetics , Feces/microbiology , Fresh Water/analysis , Water Pollution , Water Quality
5.
Water Sci Technol ; 69(6): 1349-58, 2014.
Article in English | MEDLINE | ID: mdl-24647204

ABSTRACT

The realisation of a novel concept for automated on-line monitoring of enzymatic activities in water was successfully demonstrated by long-term field testing at two remote Austrian ground water resources. The ß-D-glucuronidase (GLUC) activity was selected as a representative enzymatic model parameter for the on-line determination. But the device can be adapted for any enzymatic reaction with diagnostic relevance for microbial water quality monitoring, as demonstrated for the ß-D-galactosidase activity. Automated filtration of volumes up to 5 litres supports sensitive quantification of enzymatic activities. Internet-based data transfer, using internal control parameters for verification and a dynamic determination of the limit of quantification, enabled robust enzymatic on-line monitoring during a 2-year period. A proportion of 5,313 out of 5,506 GLUC activity measurements (96.5%) could be positively verified. Hydrological (discharge, gauge, turbidity, temperature, pH, electric conductivity, spectral absorbance coefficient at 254 nm) as well as microbiological parameters (Escherichia coli, coliforms) were concurrently determined to characterise the investigated ground water resources. The enzymatic on-line measurements closely reflected the different hydrological conditions and contamination patterns of the test sites. Contrary to expectations, GLUC did not qualify as a proxy-parameter for the occurrence of cultivation-based E. coli contamination and warrants further detailed investigations on its indication capacity as a rapid means for microbial faecal pollution detection in such aquatic habitats. Microbial on-line monitoring is likely to become more important in the future, complementing existing surveillance strategies for water safety management. Further perspectives on the application of such analytical on-line technologies, such as their connection with event-triggered sampling and standardised diagnostics, are discussed.


Subject(s)
Environmental Monitoring/instrumentation , Glucuronidase/analysis , Groundwater/analysis , Water Microbiology , Water Supply/analysis , Water Quality
6.
Br J Cancer ; 109(9): 2368-77, 2013 Oct 29.
Article in English | MEDLINE | ID: mdl-24104966

ABSTRACT

BACKGROUND: The sigma-2 receptor has been validated as a biomarker for proliferating tumours. Second mitochondria-derived activator of caspase (Smac) is a protein released from mitochondria into the cytosol, leading to apoptosis. In this study, we investigated a sigma-2 ligand as a tumour-targeting drug delivery agent for treating ovarian cancer. METHODS: A sigma-2 ligand, SW 43, was conjugated with a Smac mimetic compound (SMC), SW IV-52s, to form SW III-123. The delivery function of the sigma-2 moiety and cell killing mechanisms of SW III-123 were examined in human ovarian cancer cell lines. RESULTS: SW III-123 internalisation into ovarian cancer cells was mediated by sigma-2 receptors. SW III-123, but not SW IV-52s or SW 43, exhibited potent cytotoxicity in human ovarian cancer cell lines SKOV-3, CaOV-3 and BG-1 after 24-h treatment, suggesting that the sigma-2 ligand successfully delivered SMC into ovarian cancer cells. SW III-123 induced rapid degradation of inhibitor of apoptosis proteins (cIAP1 and cIAP2), accumulation of NF-κB-inducing kinase (NIK) and phosphorylation of NF-κB p65, suggesting that SW III-123 activated both canonical and noncanonical NF-κB pathways in SKOV-3 cells. SW III-123 cleaved caspase-8, -9 and -3. Tumour necrosis factor alpha (TNFα) antibody markedly blocked SW III-123-induced cell death and caspase-3 activity in SKOV-3 cells, indicating that SW III-123 activated both intrinsic and extrinsic apoptotic pathways and induced TNFα-dependent cell death in SKOV-3 cells. CONCLUSION: Sigma-2 ligands are a promising tumour-targeting drug delivery agent. Sigma-2-conjugated SMC exemplifies a novel class of therapeutic drugs for treating ovarian cancer.


Subject(s)
Antineoplastic Agents/pharmacology , Antineoplastic Agents/pharmacokinetics , Intracellular Signaling Peptides and Proteins/metabolism , Mitochondrial Proteins/metabolism , Ovarian Neoplasms/drug therapy , Receptors, sigma/metabolism , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Apoptosis Regulatory Proteins/metabolism , Caspases/metabolism , Cell Death/drug effects , Cell Line, Tumor , Drug Delivery Systems , Female , Humans , Ligands , NF-kappa B/metabolism , Ovarian Neoplasms/metabolism , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/metabolism
7.
Appl Environ Microbiol ; 79(16): 5089-92, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23747707

ABSTRACT

During a 3-year study, Clostridium perfringens was investigated in defined fecal sources from a temperate alluvial backwater area of a large river system. The results reveal that using C. perfringens as a conservative water quality indicator for total fecal pollution monitoring is no longer justified but suggest that it can be used as a tracer for excreta from nonherbivorous wildlife and human sewage.


Subject(s)
Artiodactyla/microbiology , Birds/microbiology , Clostridium perfringens/isolation & purification , Environmental Monitoring/methods , Groundwater/microbiology , Pets/microbiology , Animals , Austria , Feces/microbiology , Humans , Seasons , Sewage/microbiology
8.
Br J Cancer ; 106(4): 693-701, 2012 Feb 14.
Article in English | MEDLINE | ID: mdl-22251921

ABSTRACT

BACKGROUND: The sigma-2 receptor has been identified as a biomarker of proliferating cells in solid tumours. In the present study, we studied the mechanisms of sigma-2 ligand-induced cell death in the mouse breast cancer cell line EMT-6 and the human melanoma cell line MDA-MB-435. METHODS: EMT-6 and MDA-MB-435 cells were treated with sigma-2 ligands. The modulation of multiple signaling pathways of cell death was evaluated. RESULTS: Three sigma-2 ligands (WC-26, SV119 and RHM-138) induced DNA fragmentation, caspase-3 activation and PARP-1 cleavage. The caspase inhibitor Z-VAD-FMK partially blocked DNA fragmentation and cytotoxicity caused by these compounds. These data suggest that sigma-2 ligand-induced apoptosis and caspase activation are partially responsible for the cell death. WC-26 and siramesine induced formation of vacuoles in the cells. WC-26, SV119, RHM-138 and siramesine increased the synthesis and processing of microtubule-associated protein light chain 3, an autophagosome marker, and decreased the expression levels of the downstream effectors of mammalian target of rapamycin (mTOR), p70S6K and 4EBP1, suggesting that sigma-2 ligands induce autophagy, probably by inhibition of the mTOR pathway. All four sigma-2 ligands decreased the expression of cyclin D1 in a time-dependent manner. In addition, WC-26 and SV119 mainly decreased cyclin B1, E2 and phosphorylation of retinoblastoma protein (pRb); RHM-138 mainly decreased cyclin E2; and 10 µM siramesine mainly decreased cyclin B1 and pRb. These data suggest that sigma-2 ligands also impair cell-cycle progression in multiple phases of the cell cycle. CONCLUSION: Sigma-2 ligands induce cell death by multiple signalling pathways.


Subject(s)
Cell Death/drug effects , Ligands , Receptors, sigma/metabolism , Signal Transduction , Animals , Apoptosis/drug effects , Autophagy/drug effects , Cell Cycle/drug effects , Cell Line, Tumor , Humans , Mice
9.
Environ Sci Technol ; 45(9): 4038-45, 2011 May 01.
Article in English | MEDLINE | ID: mdl-21466151

ABSTRACT

Water resource management must strive to link catchment information with water quality monitoring. The present study attempted this for the field of microbial fecal source tracking (MST). A fecal pollution source profile based on catchment data (e.g., prevalence of fecal sources) was used to formulate a hypothesis about the dominant sources of pollution in an Austrian mountainous karst spring catchment. This allowed a statistical definition of methodical requirements necessary for an informed choice of MST methods. The hypothesis was tested in a 17-month investigation of spring water quality. The study followed a nested sampling design in order to cover the hydrological and pollution dynamics of the spring and to assess effects such as differential persistence between parameters. Genetic markers for the potential fecal sources as well as microbiological, hydrological, and chemo-physical parameters were measured. The hypothesis that ruminant animals were the dominant sources of fecal pollution in the catchment was clearly confirmed. It was also shown that the concentration of ruminant markers in feces was equally distributed in different ruminant source groups. The developed approach provides a tool for careful decision-making in MST study design and might be applied on various types of catchments and pollution situations.


Subject(s)
Environmental Monitoring/methods , Feces/microbiology , Water Microbiology , Water Pollution/analysis , Water Supply/analysis , Animals , Austria , Bacteroidetes/isolation & purification , Ruminants , Soil Microbiology
10.
Biotechnol Biofuels ; 14(1): 193, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34598727

ABSTRACT

BACKGROUND: Even if the loss of production capacity of a microorganism is said to be a serious problem in various biotechnology industries, reports in literature are rather rare. Strains of the genera Trichoderma reesei are used for large-scale production of cellulases, which are needed in food and feed, textile, paper industries and biofuel production. RESULTS: Here, we describe the phenomenon of spontaneous degeneration of T. reesei strains during large-scale cultivation. The phenotype of the degenerated population is characterized most importantly by a loss of any cellulase formation. Interestingly, promoter regions of relevant genes had a more compact chromatin in the (cel -) strains compared to productive strains. For a systematic investigation of the phenomenon a protocol for artificially induced and lab-scaled strain degeneration was developed. This workflow allows to determine the degeneration rate and thus, to compare the occurrence of a degenerated population in differently productive strains on the one hand, and to monitor the success of any strategies to prevent or decrease the degeneration on the other hand. While highly productive strains have higher degeneration rates compared to moderate producers, the degeneration can hardly be triggered in moderate producers. The observed (cel -) phenotype is not caused by a mutation in the gene encoding the essential transactivator Xyr1. The development of a non-producing population is also not triggered by any compounds released by either producing or non-producing cells. CONCLUSIONS: The extent of the occurrence of a degenerated strain population relates to the production capacity of the strain and goes along with chromatin condensation in relevant promoter regions.

11.
J Appl Microbiol ; 109(5): 1599-608, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20629798

ABSTRACT

AIMS: This study evaluated the applicability of standard faecal indicator bacteria (SFIB) for alpine mountainous water resources monitoring. METHODS AND RESULTS: Escherichia coli, enterococci (ENTC) and Clostridium perfringens were investigated by standard or frequently applied phenotypic and genotypic methods in a broad range of animal and human faecal sources in a large alpine mountainous area. Clostridium perfringens occurred only in human, livestock and carnivorous source groups in relevant average concentrations (log 4·7-7·0CFU g(-1) ) but not in herbivorous wildlife sources. Escherichia coli proved to be distributed in all faecal source groups with remarkably balanced average concentrations (log 7·0-8·4CFU g(-1) ). Except for single faecal samples from the cattle source group, prevalence rates for ENTC source groups were generally >87% with average concentrations of log 5·3-7·7 CFUg(-1) . To test the faecal indication capacity in the environment, faecal prevalence data were comparatively analysed with results from the concurrently performed multi-parametric microbial source tracking effort on karst spring water quality from the investigated alpine mountainous catchment (Reischer et al. 2008; Environ Microbiol 10:2598-2608). CONCLUSION: Escherichia coli and enterococci are reliable faecal indicators for alpine mountainous water resources monitoring, although E. coli is the more sensitive one. Clostridium perfringens did not prove to be an indicator of general faecal pollution but is suggested a conservative microbial source tracking marker for anthropogenic faecal influence. SIGNIFICANCE AND IMPACT OF THE STUDY: Applicability of SFIB is currently hotly debated. This is the first study providing comprehensive information on the applicability of SFIB at alpine mountainous habitats.


Subject(s)
Animals, Wild , Enterococcus/physiology , Environmental Monitoring/methods , Escherichia coli/physiology , Feces/microbiology , Livestock , Water Microbiology , Altitude , Animals , Cattle , Clostridium perfringens/physiology , Humans , Sewage/microbiology , Water Pollutants/analysis , Water Supply/standards
12.
Water Sci Technol ; 62(8): 1898-906, 2010.
Article in English | MEDLINE | ID: mdl-20962406

ABSTRACT

Because spring water quality from alpine karst aquifers can change very rapidly during event situations, water abstraction management has to be performed in near real-time. Four summer events (2005-2008) at alpine karst springs were investigated in detail in order to evaluate the spectral absorption coefficient at 254 nm (SAC254) as a real-time early warning proxy for faecal pollution. For the investigation Low-Earth-Orbit (LEO) Satellite-based data communication between portable hydrometeorological measuring stations and an automated microbiological sampling device was used. The method for event triggered microbial sampling and analyzing was already established and described in a previous paper. Data analysis including on-line event characterisation (i.e. precipitation, discharge, turbidity, SAC254) and comprehensive E. coli determination (n>800) indicated that SAC254 is a useful early warning proxy. Irrespective of the studied event situations SAC254 always increased 3 to 6 hours earlier than the onset of faecal pollution, featuring different correlation phases. Furthermore, it seems also possible to use SAC254 as a real-time proxy parameter for estimating the extent of faecal pollution after establishing specific spring and event-type calibrations that take into consideration the variability of the occurrence and the transferability of faecal material It should be highlighted that diffuse faecal pollution from wildlife and live stock sources was responsible for spring water contamination at the investigated catchments. In this respect, the SAC254 can also provide useful information to support microbial source tracking efforts where different situations of infiltration have to be investigated.


Subject(s)
Environmental Monitoring/methods , Escherichia coli/isolation & purification , Feces/microbiology , Fresh Water/microbiology , Water Microbiology , Water Pollution/analysis , Absorption , Altitude , Austria , Colony Count, Microbial , Environmental Monitoring/statistics & numerical data , Floods , Fresh Water/analysis , Hydrodynamics , Seasons , Time Factors , Water Microbiology/standards , Water Supply/standards
13.
Cesk Slov Oftalmol ; 76(3): 130-134, 2020.
Article in English | MEDLINE | ID: mdl-33126809

ABSTRACT

The work deals with atypical conjunctival infection of Czech patient with Oestrus ovis larvae. Ophthalmomyiasis is infestation of mammalian eyes by the larvae or worms of some flies. The most common cause of human myiasis is the Sheep. Shepherds are infected in habitats, but human eye disease outside the areas of abundant hamsters is rare. We describe a case of eye disease in a middle-aged man from the Czech Republic who spent a summer holiday seven weeks before examination in the north of Greece. During the first examination he was completely treated and no further problems were reported. Ophthalmomyiasis externa should be considered as a possible infection of travelers to the southern endemic regions when returning with an acute causeless onset of a one-sided foreign body sensation in the eye.


Subject(s)
Diptera , Eye Infections, Parasitic , Myiasis , Animals , Czech Republic , Eye Infections, Parasitic/diagnosis , Humans , Infant , Larva , Male , Middle Aged , Myiasis/diagnosis , Sheep
14.
Environ Microbiol ; 10(10): 2598-608, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18564182

ABSTRACT

The impairment of water quality by faecal pollution is a global public health concern. Microbial source tracking methods help to identify faecal sources but the few recent quantitative microbial source tracking applications disregarded catchment hydrology and pollution dynamics. This quantitative microbial source tracking study, conducted in a large karstic spring catchment potentially influenced by humans and ruminant animals, was based on a tiered sampling approach: a 31-month water quality monitoring (Monitoring) covering seasonal hydrological dynamics and an investigation of flood events (Events) as periods of the strongest pollution. The detection of a ruminant-specific and a human-specific faecal Bacteroidetes marker by quantitative real-time PCR was complemented by standard microbiological and on-line hydrological parameters. Both quantitative microbial source tracking markers were detected in spring water during Monitoring and Events, with preponderance of the ruminant-specific marker. Applying multiparametric analysis of all data allowed linking the ruminant-specific marker to general faecal pollution indicators, especially during Events. Up to 80% of the variation of faecal indicator levels during Events could be explained by ruminant-specific marker levels proving the dominance of ruminant faecal sources in the catchment. Furthermore, soil was ruled out as a source of quantitative microbial source tracking markers. This study demonstrates the applicability of quantitative microbial source tracking methods and highlights the prerequisite of considering hydrological catchment dynamics in source tracking study design.


Subject(s)
Bacteroidetes/isolation & purification , Feces/microbiology , Water Microbiology , Water Pollution , Animals , Colony Count, Microbial , DNA, Bacterial/isolation & purification , Environmental Monitoring , Humans , Polymerase Chain Reaction/methods , Ruminants
15.
Microbiol Res ; 163(2): 140-7, 2008.
Article in English | MEDLINE | ID: mdl-16730965

ABSTRACT

Spring water from alpine catchments are important water resources but they can be vulnerable against faecal contamination. Potential faecal contamination sources are wildlife populations, pasturing activities, or alpine tourism. Unfortunately, no faecal source tracking method is available to date which is sensitive enough for appropriate spring water monitoring and source allocation. Our purpose was to develop a Duplex Scorpion real-time PCR approach for the specific and sensitive quantification of Bacteroides sp. 16S rDNA fragments from human and cattle origin. By the developed approach, detection of plasmids, carrying the respective biomarker sequence, was possible over a range of more than seven orders of magnitudes down to six copy numbers per PCR assay. Furthermore, the Duplex Scorpion real-time PCR allowed the specific quantification down to 50 targets in plasmid spiked spring water matrices. Results indicate that microbial source tracking appears feasible in spring water habitats by probe-based real-time PCR technologies. However, preliminary testing of the established approach on faecal samples collected from a representative alpine habitat did not allow unambiguous source allocation in all cases. In the future, the available sequence database has thus to be widened to allow reliable source tracking in alpine spring watersheds and even expand this approach to other potential faecal sources.


Subject(s)
Bacteroides/isolation & purification , Fresh Water/microbiology , Polymerase Chain Reaction/methods , Animals , Bacteroides/genetics , Base Sequence , Cattle , DNA Primers/analysis , DNA Primers/genetics , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Feces/microbiology , Humans , Molecular Probe Techniques/economics , Molecular Probes/economics , Molecular Probes/genetics , Molecular Sequence Data , Plasmids/analysis , Plasmids/genetics , RNA, Ribosomal, 16S/genetics , Sensitivity and Specificity , Sequence Alignment , Sequence Analysis, DNA
16.
Water Sci Technol ; 58(4): 899-909, 2008.
Article in English | MEDLINE | ID: mdl-18776628

ABSTRACT

Data communication via Low-Earth-Orbit (LEO) Satellites between portable hydrometeorological measuring stations is the backbone of our system. This networking allows automated event sampling with short time increments also for E. coli field analysis. All activities of the course of the event-sampling can be observed on an internet platform based on a Linux-Server. Conventionally taken samples compared with the auto-sampling procedure revealed corresponding results and were in agreement with the ISO 9308-1 reference method. E. coli concentrations were individually corrected by event specific inactivation coefficients (0.10-0.14 day(-1)), compensating losses due to sample storage at spring temperature in the auto sampler.Two large summer events in 2005/2006 at an important alpine karst spring (LKAS2) were monitored including detailed analysis of E. coli dynamics (n = 271) together with comprehensive hydrological characterisations. High-resolution time series demonstrated a sudden increase of E. coli concentrations in spring water (approximately 2 log10 units) with a specific time delay after the beginning of the event. Statistical analysis suggested the spectral absorption coefficient measured at 254 nm (SAC254) as an early warning surrogate for real time monitoring of faecal input. Together with the LEO-satellite based system it is a helpful tool for early-warning systems in the field of drinking water protection.


Subject(s)
Environmental Monitoring/instrumentation , Escherichia coli/isolation & purification , Fresh Water/microbiology , Water Microbiology , Colony Count, Microbial , Environmental Monitoring/methods , Escherichia coli/cytology , Reproducibility of Results , Water Supply/analysis
17.
Water Res ; 124: 543-555, 2017 11 01.
Article in English | MEDLINE | ID: mdl-28806705

ABSTRACT

The microbial faecal pollution of rivers has wide-ranging impacts on a variety of human activities that rely on appropriate river water quality. Thus, detailed knowledge of the extent and origin of microbial faecal pollution is crucial for watershed management activities to maintain safe water use. In this study, the microbial faecal pollution levels were monitored by standard faecal indicator bacteria (SFIB) along a 2580 km stretch of the Danube, the world's most international river, as well as the Danube's most important tributaries. To track the origin of faecal pollution, host-associated Bacteroidetes genetic faecal marker qPCR assays for different host groups were applied in concert with SFIB. The spatial resolution analysis was followed by a time resolution analysis of faecal pollution patterns over 1 year at three selected sites. In this way, a comprehensive faecal pollution map of the total length of the Danube was created, combining substantiated information on both the extent and origin of microbial faecal pollution. Within the environmental data matrix for the river, microbial faecal pollution constituted an independent component and did not cluster with any other measured environmental parameters. Generally, midstream samples representatively depicted the microbial pollution levels at the respective river sites. However, at a few, somewhat unexpected sites, high pollution levels occurred in the lateral zones of the river while the midstream zone had good water quality. Human faecal pollution was demonstrated as the primary pollution source along the whole river, while animal faecal pollution was of minor importance. This study demonstrates that the application of host-associated genetic microbial source tracking markers in concert with the traditional concept of microbial faecal pollution monitoring based on SFIB significantly enhances the knowledge of the extent and origin of microbial faecal pollution patterns in large rivers. It constitutes a powerful tool to guide target-oriented water quality management in large river basins.


Subject(s)
Environmental Monitoring , Feces , Water Pollution , Animals , Bacteroidetes , Humans , Rivers , Water Microbiology
18.
J Microbiol Methods ; 67(2): 281-93, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16828184

ABSTRACT

A novel and highly reproducible amplified fragment length polymorphism (AFLP) typing approach was developed for typing of Enterococcus strains from the environment. Pooled and corresponding single faecal sample isolates were analysed to test the efficiency and coverage of dominant isolates for future sampling procedures. AFLP development was based on the selection of appropriate restriction enzymes and the design of adaptors and primers which was supported by in silico optimisation of selective bases using Enterococcus spp. genome data. Three optimal combinations of selective bases at the 3' end of the designed primers (i.e., CC, GG, CG) could be determined. AFLP fragment analysis using a capillary sequencer and intralane standardisation resulted in excellent methodical stability (> or =98% similarity for GG and > or =94% similarity for CC). Furthermore, the developed typing method was evaluated on 16 type trains of the genera Enterococcus and Streptococcus and 398 faecal isolates of cow pats from five alpine pastures in a karstic catchment area. Statistical analysis revealed a discrimination capacity of DI > or =0.95 (Simpson Diversity Index) and a reproducibility level of > or =94% similarity indicating the methods high typing capacity and robustness. Results of the comparative analysis of single and pooled faecal samples indicate that for a "strain to strain" based faecal source tracking, pooled faecal samples rather than single faecal samples are likely to be the most efficient sampling strategy for collecting the abundant corresponding strains.


Subject(s)
Cattle/microbiology , Enterococcus/classification , Environmental Microbiology , Feces/microbiology , Polymerase Chain Reaction/veterinary , Animals , Cluster Analysis , DNA Restriction Enzymes/metabolism , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Enterococcus/genetics , Enterococcus/isolation & purification , Female , Genetic Variation , Polymerase Chain Reaction/methods , Polymorphism, Restriction Fragment Length , Reproducibility of Results , Specimen Handling/veterinary , Streptococcus/classification , Streptococcus/genetics , Streptococcus/isolation & purification
19.
Cancer Res ; 57(1): 156-61, 1997 Jan 01.
Article in English | MEDLINE | ID: mdl-8988058

ABSTRACT

sigma 1 and sigma 2 receptors have been shown to exist in a number of rodent and human tumor cell lines. Although their expression is heterogeneous and their function is unknown, sigma receptors have been proposed as potential targets for diagnostic tumor-imaging agents. In this study, the density of sigma 2 receptors in proliferative (P) and quiescent (Q) cells of the mouse mammary adenocarcinoma, line 66, was examined. Scatchard analyses of sigma 2 receptors were performed on membrane preparations of 66 P cells from 3-day cultures and 66 Q cells from 7-, 10-, and 12-day cultures. The Scatchard studies revealed that 66 P cells had approximately 10 times more sigma 2 receptors/cell than the 66 Q cells from 10-day cultures. Although > 97% of the cells were quiescent after 7 days in culture, the maximum differential in the sigma 2 expression between 66 P and 66 Q cells was not attained until these cells had been in culture for 10 days. These data suggest that ligands labeled with positron-emitting or single photon-emitting radionuclides, which selectively bind sigma 2 receptors, have the potential to noninvasively assess the proliferative status of human breast tumors.


Subject(s)
Biomarkers, Tumor/metabolism , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/pathology , Receptors, sigma/metabolism , Animals , Cell Division , Mice , Tumor Cells, Cultured
20.
Water Res ; 90: 265-276, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26745175

ABSTRACT

This was a detailed investigation of the seasonal occurrence, dynamics, removal and resistance of human-associated genetic Bacteroidetes faecal markers (GeBaM) compared with ISO-based standard faecal indicator bacteria (SFIB), human-specific viral faecal markers and one human-associated Bacteroidetes phage in raw and treated wastewater of municipal and domestic origin. Characteristics of the selected activated sludge wastewater treatment plants (WWTPs) from Austria and Germany were studied in detail (WWTPs, n = 13, connected populations from 3 to 49000 individuals), supported by volume-proportional automated 24-h sampling and chemical water quality analysis. GeBaM were consistently detected in high concentrations in raw (median log10 8.6 marker equivalents (ME) 100 ml(-1)) and biologically treated wastewater samples (median log10 6.2-6.5 ME 100 ml(-1)), irrespective of plant size, type and time of the season (n = 53-65). GeBaM, Escherichia coli, and enterococci concentrations revealed the same range of statistical variability for raw (multiplicative standard deviations s* = 2.3-3.0) and treated wastewater (s* = 3.7-4.5), with increased variability after treatment. Clostridium perfringens spores revealed the lowest variability for raw wastewater (s* = 1.5). In raw wastewater correlations among microbiological parameters were only detectable between GeBaM, C. perfringens and JC polyomaviruses. Statistical associations amongst microbial parameters increased during wastewater treatment. Two plants with advanced treatment were also investigated, revealing a minimum log10 5.0 (10th percentile) reduction of GeBaM in the activated sludge membrane bioreactor, but no reduction of the genetic markers during UV irradiation (254 nm). This study highlights the potential of human-associated GeBaM to complement wastewater impact monitoring based on the determination of SFIB. In addition, human-specific JC polyomaviruses and adenoviruses seem to be a valuable support if highly specific markers are needed.


Subject(s)
Bacteroidetes/isolation & purification , Feces/microbiology , Wastewater/microbiology , Water Microbiology , Adenoviridae/isolation & purification , Austria , Bioreactors , Clostridium perfringens/isolation & purification , Enterococcus/isolation & purification , Environmental Monitoring , Escherichia coli/isolation & purification , Germany , Humans , JC Virus/isolation & purification , Models, Statistical , Sewage/microbiology , Ultraviolet Rays , Waste Disposal, Fluid , Water Pollutants , Water Purification
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