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1.
Eur Cell Mater ; 41: 739-755, 2021 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-34137455

RESUMEN

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for pain management during recovery from orthopaedic surgery. NSAID use is associated with increased risk of bone healing complications but it is currently unknown whether NSAIDs increase the risk of developing an orthopaedic-device-related infection (ODRI) and/or affects its response to antibiotic therapy. The present study aimed to determine if administration of the NSAID carprofen [a preferential cyclooxygenase-2 (COX-2) inhibitor] negatively affected Staphylococcus epidermidis (S. epidermidis) bone infection, or its subsequent treatment with antibiotics, in a rodent ODRI model. Sterile or S. epidermidis-contaminated screws (~ 1.5 x 106 CFU) were implanted into the proximal tibia of skeletally mature female Wistar rats, in the absence or presence of daily carprofen administration. A subset of infected animals received antibiotics (rifampicin plus cefazolin) from day 7 to 21, to determine if carprofen affected antibiotic efficacy. Bone changes were monitored using in vivo µCT scanning and histological analysis. The risk of developing an infection with carprofen administration was assessed in separate animals at day 9 using a screw contaminated with 10² CFU S. epidermidis. Quantitative bacteriological analysis assessed bacterial load at euthanasia. In the 28-day antibiotic treatment study, carprofen reduced osteolysis but markedly diminished reparative bone formation, although total bacterial load was not affected at euthanasia. Antibiotic efficacy was negatively affected by carprofen (carprofen: 8/8 infected; control: 2/9 infected). Finally, carprofen increased bacterial load and diminished bone formation following reduced S. epidermidis inoculum (10² CFU) at day 9. This study suggests that NSAIDs with COX-2 selectivity reduce antibiotic efficacy and diminish reparative responses to S. epidermidis ODRI.


Asunto(s)
Antibacterianos/farmacología , Antiinflamatorios no Esteroideos/farmacología , Carbazoles/farmacología , Infecciones Relacionadas con Catéteres/tratamiento farmacológico , Osteogénesis/efectos de los fármacos , Tibia/efectos de los fármacos , Animales , Inhibidores de la Ciclooxigenasa 2/farmacología , Femenino , Ortopedia/métodos , Ratas , Ratas Wistar , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus epidermidis/efectos de los fármacos
2.
Anaesthesist ; 67(7): 504-511, 2018 07.
Artículo en Alemán | MEDLINE | ID: mdl-29767825

RESUMEN

BACKGROUND: Palliative sedation (PS) serves as a therapeutic option in cases of otherwise intractable suffering. As the use of sedative and hypnotic medication in many diverse situations is a core competency of anesthesiology, anesthesiologists are confronted with questions of sedative therapy at the end of life in institutions for specialized palliative care, in intensive care units and intermediate care wards. In recent years a number of guidelines have been published internationally but so far no official guidelines exist in Germany. The most recognized document is the European Association for Palliative Care (EAPC) framework on PS. This project aims to develop a German language template for the preparation, application, documentation and evaluation of PS according to the current frameworks, especially the EAPC framework on PS. METHODS: A first draft of the template was generated by the project team using the EAPC framework and individual templates of various institutions, which had been collected during a previous project. Professionals (n = 136) from inpatient and outpatient specialist palliative and hospice care were invited to assess all items of the draft regarding "relevance", "wording" and "feasibility" in an online Delphi survey (Unipark®, Questback, Cologne, Germany). After the second Delphi round an expert panel was asked to reflect the results and generate a final draft. Approval was granted if acceptance exceeded 75% of participants. RESULTS: The 3 rounds of the Delphi process were completed by 64, 46 and 41 participants, respectively. The Delphi process as well as the expert panel led to significant changes of the template. The indications for PS had to be clarified. The significance of documentation of vital parameters, such as oxygen saturation, blood pressure or respiratory rate during PS was intensively discussed. In many teams, predominantly hospice or outpatient palliative care teams, it seems to be difficult to measure these parameters or it is regarded as inappropriate in a palliative care setting. In contrast, the EAPC framework recommends monitoring of vital parameters in cases of intermittent or respite sedation. Finally, a solution was found to support documentation of additional data without the explicit mentioning of specific parameters. After the third Delphi round, all 16 items of the documentation template reached consensus with respect to relevance (82.9-100%), clarity of wording (80.5-100%), and feasibility in practice (78-100%). CONCLUSION: This article provides an empirically based, multiprofessional consented documentation template for PS. Core elements of the documentation of PS are the indications and the decision process towards PS. During the treatment, at least the level of sedation and the symptom burden have to be recorded. The documentation of vital signs during PS remains a highly disputed topic. The presented data suggest that especially in outpatient settings and in hospices measuring and documentation of vital parameters is uncommon and therefore is often regarded as not feasible. This template can help to support the medically and ethically sound use of PS and facilitate research. The template can be accessed at http://www.palliativmedizin.uk-erlangen.de/forschung/downloads/ .


Asunto(s)
Sedación Profunda/normas , Documentación/normas , Guías como Asunto , Cuidados Paliativos/normas , Anestesia , Consenso , Toma de Decisiones , Atención a la Salud , Alemania , Humanos , Lenguaje , Encuestas y Cuestionarios
3.
Yeast ; 32(1): 145-57, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24910400

RESUMEN

Trichoderma atroviride IMI 206040 synthesizes the coconut lactone 6-pentyl-α-pyrone (6-PAP) de novo and Aspergillus niger DSM 821 produces the rose-like flavour compound 2-phenylethanol (2-PE) from the precursor l-phenylalanine. Here, microparticles of different chemical composition and nominal particle diameter in the range 5-250 µm were added to shake-flask cultures of both fungi to investigate the particles' effect on product formation. Maximum 2-PE concentration increased by a factor of 1.3 to 1430 mg/l with the addition of 2% w/v talc (40 µm diameter). Maximum 6-PAP concentration increased by a factor of 2 to 40 mg/l with the addition of 2% w/v iron (II, III) oxide. The influence of ions leaching out of the particles was investigated by cultivating the fungi in leached particle medium. For the first time, the positive effect of the microparticle-enhanced cultivation (MPEC) technique on the microbial production of volatile metabolites, here flavour compounds from submerged fungal cultures, is demonstrated. The effect is strain- and particle-specific.


Asunto(s)
Aspergillus niger/metabolismo , Técnicas de Cultivo Celular por Lotes/métodos , Fenilalanina/química , Alcohol Feniletílico/metabolismo , Pironas/metabolismo , Trichoderma/metabolismo , Aspergillus niger/genética , Técnicas de Cultivo Celular por Lotes/instrumentación , Tamaño de la Partícula , Fenilalanina/metabolismo , Trichoderma/genética
5.
Bioinformatics ; 27(4): 534-40, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21149278

RESUMEN

MOTIVATION: The reconstruction of metabolic networks at the genome scale has allowed the analysis of metabolic pathways at an unprecedented level of complexity. Elementary flux modes (EFMs) are an appropriate concept for such analysis. However, their number grows in a combinatorial fashion as the size of the metabolic network increases, which renders the application of EFMs approach to large metabolic networks difficult. Novel methods are expected to deal with such complexity. RESULTS: In this article, we present a novel optimization-based method for determining a minimal generating set of EFMs, i.e. a convex basis. We show that a subset of elements of this convex basis can be effectively computed even in large metabolic networks. Our method was applied to examine the structure of pathways producing lysine in Escherichia coli. We obtained a more varied and informative set of pathways in comparison with existing methods. In addition, an alternative pathway to produce lysine was identified using a detour via propionyl-CoA, which shows the predictive power of our novel approach. AVAILABILITY: The source code in C++ is available upon request.


Asunto(s)
Biología Computacional/métodos , Redes y Vías Metabólicas/genética , Modelos Teóricos , Biología de Sistemas/métodos , Acilcoenzima A/metabolismo , Simulación por Computador , Escherichia coli/genética , Escherichia coli/metabolismo , Genoma Bacteriano , Lisina/biosíntesis
6.
Adv Appl Microbiol ; 72: 89-136, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20602989

RESUMEN

Because of their metabolic diversity, high production capacity, secretion efficiency, and capability of carrying out posttranslational modifications, filamentous fungi are widely exploited as efficient cell factories in the production of metabolites, bioactive substances, and native or heterologous proteins, respectively. There is, however, a complex relationship between the morphology of these microorganisms, transport phenomena, the viscosity of the cultivation broth, and related productivity. The morphological characteristics vary between freely dispersed mycelia and distinct pellets of aggregated biomass, every growth form having a distinct influence on broth rheology. Hence, the advantages and disadvantages for mycelial or pellet cultivation have to be balanced out carefully. Because of the still inadequate understanding of the morphogenesis of filamentous microorganisms, fungal morphology is often a bottleneck of productivity in industrial production. To obtain an optimized production process, it is of great importance to gain a better understanding of the molecular and cell biology of these microorganisms as well as the relevant approaches in biochemical engineering. In this chapter, morphology and growth of filamentous fungi are described, with special attention given to specific problems as they arise from fungal growth forms; growth and mass transfer in fungal biopellets are discussed as an example. To emphasize the importance of the flow behavior of filamentous cultivation broths, an introduction to rheology is also given, reviewing important rheological models and recent studies concerning rheological parameters. Furthermore, current knowledge on morphology and productivity in relation to the environom is outlined in the last section of this review.


Asunto(s)
Biomasa , Reactores Biológicos/microbiología , Hongos/crecimiento & desarrollo , Microbiología Industrial/métodos , Micelio/crecimiento & desarrollo , Hongos/ultraestructura , Micelio/ultraestructura , Reología , Viscosidad
7.
Science ; 293(5530): 711-4, 2001 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-11408621

RESUMEN

The microtubule-binding protein tau has been implicated in the pathogenesis of Alzheimer's disease and related disorders. However, the mechanisms underlying tau-mediated neurotoxicity remain unclear. We created a genetic model of tau-related neurodegenerative disease by expressing wild-type and mutant forms of human tau in the fruit fly Drosophila melanogaster. Transgenic flies showed key features of the human disorders: adult onset, progressive neurodegeneration, early death, enhanced toxicity of mutant tau, accumulation of abnormal tau, and relative anatomic selectivity. However, neurodegeneration occurred without the neurofibrillary tangle formation that is seen in human disease and some rodent tauopathy models. This fly model may allow a genetic analysis of the cellular mechanisms underlying tau neurotoxicity.


Asunto(s)
Modelos Animales de Enfermedad , Drosophila melanogaster , Enfermedades Neurodegenerativas/patología , Neuronas/ultraestructura , Proteínas tau/metabolismo , Acetilcolina/metabolismo , Envejecimiento , Animales , Animales Modificados Genéticamente , Encéfalo/patología , Encéfalo/ultraestructura , Drosophila melanogaster/genética , Humanos , Mutación , Degeneración Nerviosa , Terminaciones Nerviosas/metabolismo , Terminaciones Nerviosas/ultraestructura , Enfermedades Neurodegenerativas/metabolismo , Ovillos Neurofibrilares/ultraestructura , Neuronas/metabolismo , Neurópilo/ultraestructura , Fosforilación , Vacuolas/ultraestructura , Proteínas tau/química , Proteínas tau/genética
8.
Rev Sci Instrum ; 79(3): 033501, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18377004

RESUMEN

In situ commissioning of the Blower-gun injector for launching cryogenic deuterium pellets at ASDEX Upgrade tokamak was performed. This injector is designed for high repetitive launch of small pellets for edge localised modes pacing experiments. During the investigation the final injection geometry was simulated with pellets passing to the torus through a 5.5 m long guiding tube. For investigation of pellet quality at launch and after tube passage laser flash camera shadowgraphy diagnostic units before and after the tube were installed. As indicator of pellet quality we adopted the pellet mass represented by the volume of the main remaining pellet fragment. Since only two-dimensional (2D) shadow images were obtained, a reconstruction of the full three-dimensional pellet body had to be performed. For this the image was first converted into a 1-bit version prescribing an exact 2D contour. From this contour the expected value of the volume was calculated by Bayesian analysis taking into account the likely cylindrical shape of the pellet. Under appropriate injection conditions sound pellets with more than half of their nominal mass are detected after acceleration; the passage causes in average an additional loss of about 40% to the launched mass. Analyzing pellets arriving at tube exit allowed for deriving the injector's optimized operational conditions. For these more than 90% of the pellets were arriving with sound quality when operating in the frequency range 5-50 Hz.

9.
Rev Sci Instrum ; 78(2): 023504, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17578110

RESUMEN

One of the main challenges posed recently on pellet launcher systems in fusion-oriented plasma physics is the control of the plasma edge region. Strong energy bursts ejected from the plasma due to edge localized modes (ELMs) can form a severe threat for in-vessel components but can be mitigated by sufficiently frequent triggering of the underlying instabilities using hydrogen isotope pellet injection. However, pellet injection systems developed mainly for the task of ELM control, keeping the unwanted pellet fueling minimized, are still missing. Here, we report on a novel system developed under the premise of its suitability for control and mitigation of plasma edge instabilities. The system is based on the blower gun principle and is capable of combining high repetition rates up to 143 Hz with low pellet velocities. Thus, the flexibility of the accessible injection geometry can be maximized and the pellet size kept low. As a result the new system allows for an enhancement in the tokamak operation as well as for more sophisticated experiments investigating the underlying physics of the plasma edge instabilities. This article reports on the design of the new system, its main operational characteristics as determined in extensive test bed runs, and also its first test at the tokamak experiment ASDEX Upgrade.

10.
Biomed Mater Eng ; 17(4): 199-208, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17611295

RESUMEN

In the last few years, regulations for biomolecule production, and especially for extraction and purification of animal molecules such as collagen, have been reinforced to ensure the sanitary safety of the materials. To be authorized to market biomaterials based on collagen, manufacturers now have to prove that at least one step of their process is described in guidelines to inactivate prion, viruses, and bacteria. The present study focuses on the inactivation step performed during the extraction and purification of porcine type I atelocollagen. We chose to determine the reduction factor of a 1 M NaOH step on porcine parvovirus and four bacterial strains inactivation. During the extraction step, we deliberately inoculated the collagen suspension with the different microorganisms tested. Then, 1 M NaOH was added to the suspension for 1 hour at 20 degrees C. We demonstrated that this treatment totally inactivated S. aureus, P. aeruginosa, C. albicans and A. niger which are bacterial strains responsible of severe human pathology. The reduction factors reached more than 4 logs for B. cereus spores and 4 logs for the porcine parvovirus. are encouraging as those two microorganisms are known to be very resistant to inactivation.


Asunto(s)
Bacterias/efectos de los fármacos , Colágeno/aislamiento & purificación , Contaminación de Medicamentos/prevención & control , Hidróxido de Sodio/farmacología , Esterilización/métodos , Inactivación de Virus/efectos de los fármacos , Virus/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Fraccionamiento Químico/métodos , Desinfectantes/farmacología , Porcinos
11.
Gene ; 97(2): 273-6, 1991 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-1999292

RESUMEN

A gene (rtr-1) coding for the tRNAArgACG has been isolated and characterized from the nematode, Caenorhabditis elegans. The coding portion is not interrupted by an intron and is followed by a track of four thymidines associated with termination by RNA polymerase III. The predicted mature product is 76 nucleotides (nt) long including the CCA tail, and is specific for the most used Arg codon in C. elegans. The gene can be transcribed and processed in a homologous in vitro system. The 82-nt primary transcript begins at the first purine upstream from the mature tRNA 5' end and terminates after the first thymidine of the terminator signal.


Asunto(s)
Caenorhabditis/genética , Expresión Génica , ARN de Transferencia de Arginina/genética , Animales , Secuencia de Bases , Clonación Molecular , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Mapeo Restrictivo , Transcripción Genética
12.
Arch Surg ; 112(2): 210-2, 1977 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-836155

RESUMEN

Cystic adventitial degeneration (CAD) of the arteries is an uncommon cause of intermittent claudication in adults. The majority of reported cases have involved the popliteal artery and have occurred predominantly in men, and all had clinical evidence of occlusive vascular disease. An unusual example of CAD of the common femoral artery masqueraded clinically as an aneurysm, but the arteriogram was normal. It involved 5 cm of the artery and half its circumference, and was resected and replaced with a saphenous vein graft. The cyst contained clear mucoid fluid and a fibrous wall without a cyst lining. This is the eighth case reported of CAD involving the proximal segment of a large lower extremity artery. The etiology is unknown, but many authors think such cysts arise from primitive "arthrogenic" mesenchyme in the adventitia of blood vessels.


Asunto(s)
Quistes , Arteria Femoral , Quistes/etiología , Quistes/patología , Arteria Femoral/patología , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Vasculares/etiología , Enfermedades Vasculares/patología
13.
Biotechnol Bioeng ; 62(6): 739-750, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10099575

RESUMEN

Mass spectrometry in combination with tracer experiments based on 13C substrates can serve as a powerful tool for the modeling and analysis of intracellular fluxes and the investigation of biochemical networks. The theoretical background for the application of mass spectrometry to metabolic flux analysis is discussed. Mass spectrometry methods are especially useful to determine mass distribution of metabolites. Additional information gained from fragmentation of metabolites, e.g., by electron impact ionization, allows further localization of labeling positions, up to complete resolution of isotopomer pools. To effectively handle mass distributions in simulation experiments, a matrix based general methodology is formulated. The natural isotope distribution of carbon, oxygen, hydrogen and nitrogen in the target metabolites is considered by introduction of correction matrices. It is shown by simulation results for the central carbon metabolism that neglecting natural isotope distributions causes significant errors in intracellular flux distributions. By varying relative fluxes into pentosephosphate pathway and pyruvate carboxylation reaction, marked changes in the mass distributions of metabolites result, which are illustrated for pyruvate, oxaloacetate, and alpha-ketoglutarate. In addition mass distributions of metabolites are significantly influenced over a broad range by the degree of reversibility of transaldolase and transketolase reactions in the pentosephosphate pathway. The mass distribution of metabolites is very sensitive towards intracellular flux patterns and can be measured with high accuracy by routine mass spectrometry methods. Copyright 1999 John Wiley & Sons, Inc.

14.
J Agric Food Chem ; 47(7): 2733-7, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10552555

RESUMEN

Two different immunoassay (IA) formats for terbuthylazine analysis were developed and optimized using the same monoclonal antibodies. The measuring range for the dipstick IA (using an alkaline phosphatase tracer, a 5-bromo-4-chloroindolylphosphate/nitro blue tetrazolium substrate and a portable reflectometer) was from 3 to 300 microg/kg. The teststrip IA (investigating a horseradish peroxidase tracer, a luminol substrate, and a portable luminometer prototype developed by Immunotek, Moscow, Russia) had a measuring range from 0.05 to 10 microg/kg. From 24 soil samples collected in the Veneto area, Italy, 18 samples contained different amounts of terbuthylazine (but <1 microg/kg atrazine) as was analyzed by gas chromatography with mass selective detection. Eight soil samples (six positive, two negative controls) were analyzed according to the two IA formats. Whereas the dipstick with reflectance detection yielded satisfying results, the test strip IA using luminescence detection has failed so far for soil samples.


Asunto(s)
Herbicidas/análisis , Inmunoensayo/métodos , Suelo/análisis , Triazinas/análisis , Cromatografía de Gases , Mediciones Luminiscentes
15.
Environ Pollut ; 107(2): 255-61, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15093003

RESUMEN

A rapid protocol was developed to measure 10 different enzymic activities from a large number of 1-cm-sliced freshly collected lake sediments. Layers heavily polluted by organic halogens (4900 mg Cl kg(-1)) revealed severe depression of phosphatase, sulfatase, leucine-aminopeptidase, chitinase, acetate esterase and butyrate esterase activities as compared to layers above and below the most polluted zone. alpha-Glucosidase, beta-glucosidase, beta-xylosidase and palmitate esterase were less affected. Methane oxidation potential was dramatically depressed in the polluted strata whereas tetrachloromethane dehalogenating activity was observed in the polluted sediment only. The sediment layers formed after the chlorine discharges into the lake had diminished to 1/10, and showed restoration of the activities close to those observed in non-recipient sediment, in spite of the persisting presence of >1000 mg of organic chlorine (kg dry wt)(-1). We conclude that certain enzymic activities involved in breakdown or oxidation of organic matter in the sediments are useful probes for assessing the degree of ecological damage and its potential for restoration in recipient lakes of industrial discharges.

16.
Health Phys ; 78(4): 438-44, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10749527

RESUMEN

222Rn and 220Rn concentrations were measured in cave dwellings and brick houses in the region of Yan'an (China) during summer 1997. The underground dwellings are built into Quaternary loess, and all investigated houses are founded on it. The median values of indoor 222Rn and 220Rn concentrations are 42 (n = 18) and 77 Bq m(-3) (n = 15) for brick houses and 92 (n = 23) and 215 (n = 17) Bq m(-3) for cave dwellings. To classify the dwellings in respect to their "cave-character," the fraction of walls having a direct contact to the loses is calculated for each dwelling. While the 222Rn concentrations are increasing with higher fractions, the 220Rn concentrations are not correlated with this fraction. On the other hand, due to the short half-life of 220Rn the distance from the measuring point to the walls is negatively correlated with the 220Rn concentration, while there is no correlation with the 222Rn concentration. Therefore, concentric isolines of 220Rn concentrations showing a strong gradient were detected in cave dwellings. An influence of the ventilation rate is distinct for 222Rn but weak for 220Rn. The effective dose rates for 222Rn and 220Rn and their progenies are calculated for brick houses (2.7 mSv y(-1)), cave dwellings (7.1 mSv y(-1)), and for traditional cave dwellings with a bed foundation built with loess (16.7 mSv y(-1)). These calculations are based on summer measurements only. It is expected that the true effective dose rates will be significantly higher.


Asunto(s)
Vivienda , Radón/análisis , China , Concentración Osmolar , Radiometría , Hijas del Radón/análisis , Contaminantes Radiactivos del Suelo/análisis
17.
Adv Hematol ; 2012: 541471, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22737171

RESUMEN

Starting as a model for developmental genetics, embryology, and organogenesis, the zebrafish has become increasingly popular as a model organism for numerous areas of biology and biomedicine over the last decades. Within haematology, this includes studies on blood cell development and function and the intricate regulatory mechanisms within vertebrate immunity. Here, we review recent studies on the immediate mechanisms mounting an inflammatory response by in vivo analyses using the zebrafish. These recently revealed novel roles of the reactive oxygen species hydrogen peroxide that have changed our view on the initiation of a granulocytic inflammatory response.

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