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Green fluorescent protein as an indicator of cryoinjury in tissues.
The fluorescence intensity of Green Fluorescent Protein (GFP) has previously been demonstrated to be an accurate indicator of cellular viability following cryoinsult in individual GFP-transfected cells. In an attempt to ascertain whether GFP fluorescence intensity may also be used as a viability indicator following cryogenic insults in whole tissues, this study examines the transient fluorescence intensity of GFP-transfected mouse hepatic tissue ex vivo following cryoinsult. The observed trends are compared with diffusion-based models. It was observed that the fluorescence intensity of the exposed tissues exhibited slow exponential decay, while the solution in which the tissues were placed inversely gained fluorescence. This slow decay (~3 h) is in contrast to the rapidly diminished fluorescence intensity (seconds) seen in GFP-cell cultures following cryoinsult. These trends suggest that mass diffusion of GFP in the interstitial space, and ultimately into the surrounding medium, is the primary mechanism which determines the fluorescence loss in cryoinjured tissues. These results suggest GFP-transfected tissues may be effectively used as indicators of cryoinjury, and hence viability, following hypothermal insult provided that a sufficiently long incubation is held before observation. It was found that a meaningful observation (15% reduction in fluorescence) could be made three hours subsequent to cryoinjury for the tissues used in this study
Prestressed Saddle Shaped Tensile Structures, An Analysis
Problem:
In today\u27s field of architecture, a great deal of emphasis is placed upon the use of new forms and new materials by a great number of architects. Yet the vast majority of these persons are not equipped to carry out this task. It is not that they do not possess the technical knowledge, it is that they do not have the right approach in tackling the problem. This is often the case when dealing with prestressed tensile structures; More specifically, saddle shaped surfaces.
Scope
This project represents an investigation of the structural principles involved in the design of prestressed saddle shaped tensile structures, the stripping down of these principles to their barest and simplest expressions, and an application of these same principles to model analysis involving the basic prestressed saddle surface structural prototype.
Procedure
This analysis is undertaken with the help of a machine which collects several types of information from the models. The machine, described in pages 64 and 65 of this work, was essential in the overall understanding of the basic structural conditions present in each particular model. A process of observation and conclusion was carried out through each individual model test and each particular model..
Observations were made on each test\u27s graphic data and were due to the author\u27s relating of these same observations to basic tensile principles. This process was carried out and was refined to the point where varying situations of structural complexity were easily related to these same principles. Conclusions were made from each individual test observation, were compared to those of other tests, And were synthesized into an overall conclusion or conclusions.
Results: The results arrived at by following this process of investigation enables the reader to make value judgements as to the condition of stress distribution on a particular model, and also gives the reader a way in which to cope with this situation. An indirect result arrived at in the process of investigation was that the reader acquires a common sense approach, not only to prestressed saddle shaped surfaces, but to the field of tensile structures as a whole
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Graffiti art and self-identity: Leaving their mark
This project focuses on graffiti art as not an unconstructive form of artwork as society might assume, but a way of coping and establishing an identity for youth mostly males who are searching for who they are
Drug resistance in community-acquired respiratory tract infections: role for an emerging antibacterial
The nasopharynx is the ecological niche where evolution towards resistance occurs in respiratory tract isolates. Dynamics of different bacterial populations in antibiotic-free multibacterial niches are the baseline that antibiotic treatments can alter by shifting the competitive balance in favor of resistant populations. For this reason, antibiotic resistance is increasingly being considered to be an ecological problem. Traditionally, resistance has implied the need for development of new antibiotics for which basic efficacy and safety data are required prior to licensing. Antibiotic development is mainly focused on demonstrating clinical efficacy and setting susceptibility breakpoints for efficacy prediction. However, additional information on pharmacodynamic data predicting absence of selection of resistance and of resistant subpopulations, and specific surveillance on resistance to core antibiotics (to detect emerging resistances and its link with antibiotic consumption in the community) are valuable data in defining the role of a new antibiotic, not only from the perspective of its therapeutic potential but also from the ecologic perspective (countering resistances to core antibiotics in the community). The documented information on cefditoren gleaned from published studies in recent years is an example of the role for an emerging oral antibacterial facing current antibiotic resistance in community-acquired respiratory tract infections
Update on the clinical utility and optimal use of cefditoren
This article reviews and updates published data on cefditoren. The in vitro activity of cefditoren and its potential pharmacokinetic/pharmacodynamic adequacy to cover emerging resistance phenotypes in the present decade is reviewed. Cefditoren’s in vitro activity against most prevalent bacterial respiratory pathogens in the community and its pharmacokinetic/pharmacodynamic profile suggests a significant role for cefditoren in the treatment of respiratory tract infections. Clinical trials (in acute exacerbations of chronic bronchitis, community-acquired pneumonia, pharyngotonsillitis, and sinusitis) performed during clinical development outside Japan, mainly in adults, are reviewed, together with new clinical studies in the treatment of pharyngotonsillitis, sinusitis, and otitis media in children, mainly in Japan, for efficacy and safety assessment. The results of these studies support the adequacy of cefditoren for the treatment of community-acquired respiratory tract infections with a safety profile similar to previous oral antibiotics. From the data reviewed, it is concluded that cefditoren is an adequate option for the treatment of mild-to-moderate community-acquired respiratory infections, especially in geographical areas with a reported prevalence of phenotypes exhibiting nonsusceptibility to common oral antibiotics
Cefditoren in upper and lower community-acquired respiratory tract infections
This article reviews and updates published data on cefditoren in the evolving scenario of resistance among the most prevalent isolates from respiratory tract infections in the community (Streptococcus pyogenes, Haemophilus influenzae, and Streptococcus pneumoniae). By relating the in vitro activity of cefditoren (in national and multinational surveillance and against isolates with emerging resistant genotypes/phenotypes) to its pharmacokinetics, the cefditoren pharmacodynamic activity predicting efficacy (in humans, animal models, and in vitro simulations) is analyzed prior to reviewing clinical studies (tonsillopharyngitis, sinusitis, acute exacerbations of chronic bronchitis, and community-acquired pneumonia) and the relationship between bacterial eradication and clinical efficacy. The high in vitro activity of cefditoren against the most prevalent respiratory isolates in the community, together with its pharmacokinetics (enabling a twice daily regimen) leading to adequate pharmacodynamic indexes covering all S. pyogenes, H. influenzae, and at least 95% S. pneumoniae isolates, makes cefditoren an antibiotic that will play a significant role in the treatment of respiratory tract infections in the community. In the clinical setting, studies carried out with cefditoren showed that treatments with the 400 mg twice daily regimen were associated with high rates of bacteriological response, even against penicillin-nonsusceptible S. pneumoniae, with good correlation between bacteriological efficacy/response and clinical outcome
Desarrollo postoxicológico y preterapeútico de una cefamicina en España
Tesis Univ. Complutense de Madrid, 1993Depto. de Inmunología, Oftalmología y ORLFac. de MedicinaTRUEpu
Desarrollo postoxicológico y preterapeútico de una cefamicina en España
Tesis Univ. Complutense de Madrid, 1993Depto. de Inmunología, Oftalmología y ORLFac. de MedicinaTRUEpu
Level forecasting in the Ebro River during flood episodes using adaptive predictive expert models
In order to minimize the catastrophic effects of floods, it is essential to have good forecasts of the flood dynamics. To carry out these forecasts, commercial computing tools use hydraulic models
based on the Saint-Venant equations. Instead of these hydraulic models, this paper proposes the use of input-output adaptive predictive expert (APE) models with properly adjusted parameters. For the initial parameter setting of the APE models used in this paper, four flood episodes occurred in the Ebro river in 2001, 2003, 2007 and 2008 were analysed. In a second stage, the flood episode occurred in February 2009 was forecasted with these adjusted models, and the results were compared to the ones made with the commercial forecasting model MIKE11.Postprint (published version
Management of odontogenic infection of pulpal and periodontal origin
The dental biofilm is a complex bacterial ecosystem that undergoes evolution, maturing and development, and thus leads to odontogenic infection. The infection is normally located in the tissues of the dental organ itself, and follows a chronic course of evolution. However, bacterial pathogens express virulence factors in the biofilm, and this together with changes in host immunity, may cause clinical exacerbations and spread of infection to other areas of the body. Odontogenic infection management should take into consideration the fact that therapeutic success lies in the control of the infectious aetiologic agent, using mechanical-surgical debridement and/or antimicrobial therapy. Debridement techniques have a fundamentally quantitative effect (by reducing the size of the inoculum) and therefore if these techniques are used alone to control infection, despite an initial clinical improvement that is sometimes prematurely considered as therapeutic success, odontopathogens may persist and the process may recur or become chronic. Microbiological examination may be helpful in defining therapeutic success in a more reliable way, it could define the prognosis of recurrence more precisely, and could enable the most appropriate antibiotic to be selected, thus increasing therapeutic efficacy. Antimicrobial therapy brings about a quantitative and qualitative change in the bacterial composition of the biofilm, in addition to being able to act on sites that are inaccessible through mechanical debridement. However, incorrect antimicrobial use can lead to a selection of resistant bacterial species in the biofilm, in addition to side effects and ecological alterations in the host. In order to minimise this risk, and obtain maximum antimicrobial effect, we need to know in which clinical situations their use is indicated, and the efficacy of different antibiotics with regard to bacteria isolated in odontogenic infection
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