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81.
82.
Patient management in Idiopathic Pulmonary Fibrosis (IPF) is largely based on societal guidelines and recommendations. A recent update by the American Thoracic Society (ATS), European Respiratory Society (ERS), Japanese Respiratory Society (JRS) and Latin American Thoracic Association (ALAT) provided updated guidance on the diagnosis and management of IPF, along with recommendations on pharmacologic and non-pharmacologic approaches to patient management. The treatment guidance is based on GRADE criteria, which rates the quality of evidence according to previously published methodology. Here we discuss how to interpret the recent guideline updates and the implications of this guidance for clinical practice. In addition we discuss the assessment and recommendations for a number of pharmacological agents that have been the focus of clinical trials over the past years. Although no single pharmacological agent was recommended by the guidelines committee, we discuss how since then, more recent data have resulted in the approval of pirfenidone in Europe, and preliminary negative findings regarding the safety of a triple therapy regimen consisting of prednisone, azathioprine and N-acetylcysteine have raised the question of whether it is no longer a treatment option. As clinicians, we must interpret the available guidance and recommendations as we consider each individual patient and as we discuss the available clinical data and the patient’s own preferences in our approach to the management of this disease.  相似文献   
83.
The Miro GTPases represent an unusual subgroup of the Ras superfamily and have recently emerged as important mediators of mitochondrial dynamics and for maintaining neuronal health. It is now well-established that these enzymes act as essential components of a Ca2+-sensitive motor complex, facilitating the transport of mitochondria along microtubules in several cell types, including dopaminergic neurons. The Miros appear to be critical for both anterograde and retrograde mitochondrial transport in axons and dendrites, both of which are considered essential for neuronal health. Furthermore, the Miros may be significantly involved in the development of several serious pathological processes, including the development of neurodegenerative and psychiatric disorders. In this review, we discuss the molecular structure and known mitochondrial functions of the Miro GTPases in humans and other organisms, in the context of neurodegenerative disease. Finally, we consider the potential human Miros hold as novel therapeutic targets for the treatment of such disease.  相似文献   
84.
85.
Klebsiella pneumoniae is a zoonotic, Gram-negative member of the family Enterobacteriaceae and is the causative agent of nosocomial septicemic, pneumonic, and urinary tract infections. Recently, pathogenic strains of K. pneumoniae sharing a hypermucoviscosity (HMV) phenotype have been attributed to multisystemic abscessation in both human and nonhuman primates. Although K. pneumoniae is a well-recognized zoonotic agent, there is a lack of general information including adequate diagnostic methods or treatments for nonhuman primates. In an effort to increase the body of knowledge of this enigmatic pathogen, K. pneumoniae isolates from African green monkeys (Chlorocebus aethiops sabaeus) on the island of St. Kitts, West Indies were genotypically and phenotypically characterized. Genetic fingerprints generated by PCR-mediated genomic fingerprinting, phenotypic characterization, and antimicrobial susceptibility all identified a high degree of similarity between the HMV and non-HMV K. pneumoniae isolates. The results obtained from this work will help establish a baseline for the development of efficacious diagnostic methods and treatment strategies for both human and nonhuman primates.  相似文献   
86.
Systems biology and its potential role in radiobiology   总被引:1,自引:0,他引:1  
About a century ago, Conrad Röentgen discovered X-rays, and Henri Becquerel discovered a new phenomenon, which Marie and Pierre Curie later coined as radio-activity. Since their seminal work, we have learned much about the physical properties of radiation and its effects on living matter. Alas, the more we discover, the more we appreciate the complexity of the biological processes that are triggered by radiation exposure and eventually lead (or do not lead) to disease. Equipped with modern biological methods of high-throughput experimentation, imaging, and vastly increased computational prowess, we are now entering an era where we can piece some of the multifold aspects of radiation exposure and its sequelae together, and develop a more systemic understanding of radiogenic effects such as radio-carcinogenesis than has been possible in the past. It is evident from the complexity of even the known processes that such an understanding can only be gained if it is supported by mathematical models. At this point, the construction of comprehensive models is hampered both by technical inadequacies and a paucity of appropriate data. Nonetheless, some initial steps have been taken already and the generally increased interest in systems biology may be expected to speed up future progress. In this context, we discuss in this article examples of relatively small, yet very useful models that elucidate selected aspects of the effects of exposure to ionizing radiation and may shine a light on the path before us.  相似文献   
87.
Ost M  Wickman M  Matulionis E  Steele B 《Oecologia》2008,158(2):205-216
The energetic incubation constraint hypothesis (EICH) for clutch size states that birds breeding in poor habitat may free up resources for future reproduction by laying a smaller clutch. The eider (Somateria mollissima) is considered a candidate for supporting this hypothesis. Clutch size is smaller in exposed nests, presumably because of faster heat loss and higher incubation cost, and, hence, smaller optimal clutch size. However, an alternative explanation is partial predation: the first egg(s) are left unattended and vulnerable to predation, which may disproportionately affect exposed nests, so clutch size may be underestimated. We experimentally investigated whether predation on first-laid eggs in eiders depends on nest cover. We then re-evaluated how nesting habitat affects clutch size and incubation costs based on long-term data, accounting for confounding effects between habitat and individual quality. We also experimentally assessed adult survival costs of nesting in sheltered nests. The risk of egg predation in experimental nests decreased with cover. Confounding between individual and habitat quality is unlikely, as clutch size was also smaller in open nests within individuals, and early and late breeders had similar nest cover characteristics. A trade-off between clutch and female safety may explain nest cover variation, as the risk of female capture by us, mimicking predation on adults, increased with nest cover. Nest habitat had no effect on female hatching weight or weight loss, while lower temperature during incubation had an unanticipated positive relationship with hatching weight. There were no indications of elevated costs of incubating larger clutches, while clutch size and colony size were positively correlated, a pattern not predicted by the ‘energetic incubation constraint’ hypothesis. Differential partial clutch predation thus offers the more parsimonious explanation for clutch size variation among habitats in eiders, highlighting the need for caution when analysing fecundity and associated life-history parameters when habitat-specific rates of clutch predation occur.  相似文献   
88.
A rare sugar xylitol. Part I: the biochemistry and biosynthesis of xylitol   总被引:1,自引:0,他引:1  
The rare sugar xylitol is a five-carbon polyol (pentitol) that has beneficial health effects. Xylitol has global markets and, therefore, it represents an alternative to current dominant sweeteners. The research on microbial reduction of d-xylose to xylitol has been focused on metabolically engineered Saccharomycess cerevisiae and Candida strains. The Candida strains have an advantage over the metabolically engineered S. cerevisiae in terms of d-xylose uptake and maintenance of the intracellular redox balance. Due to the current industrial scale production of xylitol, it has become an inexpensive starting material for the production of other rare sugar. The first part of this mini-review concentrates on the biochemistry of xylitol biosynthesis and the problems related to intracellular redox balance.  相似文献   
89.
In order to estimate microalgal carbon assimilation or production of Chlorella fusca cultures based on electron transport rate (ETR) as in vivo chlorophyll a fluorescence, it is necessary to determine the photosynthetic yield and the absorbed quanta by measuring the incident irradiance and the fraction of absorbed light, i.e., absorptance or absorption coefficient in the photosynthetic active radiation (PAR) region of the spectra. Due to difficulties associated with the determination of light absorption, ETR is commonly expressed as relative units (rETR) although this is not a good estimator of the photosynthetic production since photobiological responses depend on the absorbed light. The quantitative filter technique (QFT) is commonly used to measure the absorbed quanta of cells retained on a filter (AbQf) as estimator of the absorbed quanta of cell suspensions (AbQs) determined by using integrating spheres. In this study, light attenuation of thin-layer cell suspensions is determined by using a measuring system designed to reduce the scattering. The light attenuation is related to the absorptance as the fraction of absorbed light by both indoor and outdoor C. fusca cultures of different cell densities. A linear relation between AbQf and AbQs (R 2?=?0.9902, p?<?0.01) was observed, AbQf?=?1.98?×?AbQs, being 1.98 an amplification factor to convert AbQs values into AbQf ones. On the other hand, depending on the culture system, the convenience of the use of the absorptance, light absorption or specific light absorption coefficient expressed per area (thin-layer cascade or flat panel cultivators), volume (cylindrical and tubular photobioreactors), or chlorophyll units (any type of cultivation system) is discussed. The procedure for the measurement of light absorption presented in this study for C. fusca could be applied in other phytoplankton groups. The absorbed quanta as determined in this study can be used to express absolute ETR instead of relative ETR, since the first one provides much more relevant photobiological information of microalgae culture systems.  相似文献   
90.
Food restriction (FR) is hypothesized to decrease body fat content of an animal and thus prevent obesity. However, the response of energy budget to a continuous (CFR) or discontinuous FR (DFR) remains inconsistent. In the present study, effects of CFR or DFR and refeeding on energy budget and behavior were examined in male Swiss mice. CFR significantly decreased the energy expenditure associated with basal metabolic rate (BMR) and activity behavior, but not sufficiently to compensate for energy deficit and thus resulted in lower body mass and fat content. DFR mice had a significantly higher food intake on ad libitum days and showed increases in BMR and activity after 4 weeks’ DFR, which might resulted in lower body mass and less body fat than controls. After being refed ad libitum, both CFR and DFR mice had similar body mass, BMR, and behavioral patterns to controls but had 95% and 75% higher fat content. This suggested that not only CFR but also DFR would be a significant factor in the process of obesity for animals that were refed ad libitum. It also indicated that food restriction interrupted many times by periods of ad libitum feeding had the same long-term effects like continuous underfeeding.  相似文献   
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