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21.
Timo Hannu Maritta S. Jaakkola Leena Kivisaari Matti S. Huuskonen Tapio Vehmas 《Chronobiology international》2013,30(3):539-551
The season of birth has been suggested to influence the development of some diseases, but its role in lung fibrosis seems to not have been studied previously. The aim of this study was to investigate the relation between the season of birth and fibrotic abnormalities as detected radiologically in high‐resolution computed tomography (HRCT) among workers exposed to asbestos. The HRCT examination was performed on 528 study subjects. Multiple ordinal regression analysis adjusting for covariates was used to study the relations between birth month or season and radiological fibrosis signs. Subjects born in autumn or winter had more extensive fibrotic changes than those born in spring or summer. This applied to all fibrotic changes, apart from subpleural nodules, but only the overall fibrosis score, septal lines, and honeycombing showed statistically significantly higher values in comparison to spring births. The highest scores were detected among those born in autumn and winter months (September–February). These results suggest that there are differences in fibrotic radiological abnormalities according to the season of birth in adults exposed to asbestos. Several hypotheses could explain the observed findings, including the effects of early respiratory infections, cold temperature, and differences in air pollution levels, as well as some metabolic and hormonal effects. 相似文献
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Dilfuza Egamberdieva Gabriela Berg Kristina Lindström Leena A. Räsänen 《Plant and Soil》2013,369(1-2):453-465
Background and aims
Salt stress is an increasing problem in agricultural soils in many parts of the world, and salt tolerant cropping systems are in great demand. We investigated the effect of co-inoculation of Galega officinalis with Rhizobium galegae and two plant growth promoting Pseudomonas species on plant growth, nodulation, and N content under salt stress.Methods
The effect of inoculation with R. galegae sv. officinalis HAMBI 1141 alone and in combination with the root-colonizing Pseudomonas extremorientalis TSAU20 or Pseudomonas trivialis 3Re27 on the growth of G. officinalis exposed to salt stress (50 and 75 mM NaCl) was studied under gnotobiotic and greenhouse conditions.Results
The growth of goat’s rue was reduced at 50 and 75 mM NaCl both in the gnotobiotic sand system and in low-fertilized potting soil in the greenhouse. Co-inoculation of unstressed and salt-stressed goat’s rue with R. galegae HAMBI 1141 and either P. extremorientalis TSAU20 or P. trivialis 3Re27 significantly improved root and shoot growth and increased nodulation of plant roots in both growth systems compared with plants inoculated with R. galegae alone. The nitrogen content of co-inoculated plant roots was significantly increased at 75 mM NaCl in potting soil. Co-inoculation of G. officinalis with either of the two plant growth promoting (PGPR) Pseudomonas strains also improved root tip-colonization by R. galegae cells.Conclusions
The co-inoculation of goat’s rue with Rhizobium and PGPR Pseudomonas strains alleviated salt stress of plants grown in NaCl-amended gnotobiotic sand systems and in potting soil in the greenhouse. 相似文献23.
For more than a century, embryologists have been exploring various model systems to gain insights into developmental processes. This article presents an overview of the role of chironomid midges in embryology research since their introduction as model organisms in the 19th century. We present the vestiges of bibliography since the days of Weismann (1834–1914), who raised preliminary queries to unravel many unique features of insect embryogenesis using midges as a crucible. Unfortunately, over the years, chironomid midges got lost into obscurity as a model for developmental biology, which is evident from the paucity of developmental biology–related literature on midges in the past decades. Through this essay, the authors intend to share reminiscences of the heydays of chironomid research with the wider community of zoologists with an aim of reviving chironomid embryology. Midges not only possess the basic qualities essential for an ideal model system, but being one of the ancestral dipteran stocks, they can also prove an excellent test system for evo‐devo, transgenetic, and embryogenomic investigations that utilize methodologies at the interface of developmental biology and high‐throughput molecular genetic and genomics approach. An introspection of re‐introducing chironomid midgesas model system will be rewarding for the contemporary developmental biologists. 相似文献
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BackgroundAntenatal depression affects up to 19% of pregnant women. Some of these women are also in need of antidepressant treatment. Nevertheless, the impact of maternal antidepressant treatment and prenatal depression on the course of pregnancy, foetal development and delivery outcomes is not fully understood.MethodsWe analysed data from 24 818 women who gave birth at Kuopio University Hospital between 2002–2012. Logistic regression analysis was used to estimate associations between the use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy and the progression of pregnancy, development of the foetus and delivery outcomes.ResultsAltogether, 369 (1.5%) women used SSRIs. A regression model adjusted for age, overweight, nulliparity, prior termination, miscarriages, smoking, maternal alcohol consumption, chronic illness and polyhydramnion showed that pregnant women exposed to SSRI medication had significantly lower Apgar scores at 1 minute (p < 0.0001) and 5 minutes (p < 0.0001) and more admissions to the neonatal intensive care unit (p < 0.0001) than unexposed pregnant women. In addition, exposed newborns had longer umbilical cords (p < 0.0001) than non-exposed newborns.ConclusionIn addition to the previously known associates with maternal SSRI exposure, such as lowered Apgar scores, SSRI exposure appeared to be associated with increased umbilical cord length. The observation related to increased umbilical cord length may be explained by an SSRI-induced increase in the movements of the developing foetus. 相似文献
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Surface functionalization of nanobiomaterials for application in stem cell culture,tissue engineering,and regenerative medicine 下载免费PDF全文
Deepti Rana Keerthana Ramasamy Maria Leena Constanza Jiménez Javier Campos Paula Ibarra Ziyad S. Haidar Murugan Ramalingam 《Biotechnology progress》2016,32(3):554-567
Stem cell‐based approaches offer great application potential in tissue engineering and regenerative medicine owing to their ability of sensing the microenvironment and respond accordingly (dynamic behavior). Recently, the combination of nanobiomaterials with stem cells has paved a great way for further exploration. Nanobiomaterials with engineered surfaces could mimic the native microenvironment to which the seeded stem cells could adhere and migrate. Surface functionalized nanobiomaterial‐based scaffolds could then be used to regulate or control the cellular functions to culture stem cells and regenerate damaged tissues or organs. Therefore, controlling the interactions between nanobiomaterials and stem cells is a critical factor. However, surface functionalization or modification techniques has provided an alternative approach for tailoring the nanobiomaterials surface in accordance to the physiological surrounding of a living cells; thereby, enhancing the structural and functional properties of the engineered tissues and organs. Currently, there are a variety of methods and technologies available to modify the surface of biomaterials according to the specific cell or tissue properties to be regenerated. This review highlights the trends in surface modification techniques for nanobiomaterials and the biological relevance in stem cell‐based tissue engineering and regenerative medicine. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:554–567, 2016 相似文献
28.
Leena Thorat Dasharath P Oulkar Kaushik Banerjee Bimalendu B Nath 《Journal of biosciences》2016,41(3):331-339
Stressful environments are known to perturb developmental patterns in insects. In the purview of desiccation as a stressor, relatively little is known about the developmental consequences linked with desiccation tolerance. In this study, we have particularly focused on the exploration of the temporal profile of postembryonic development in response to desiccation exposure in Drosophila melanogaster and the associated trade-offs. We document a correlation between variations in 20-hydroxyecdysone levels and the altered timing of metamorphic events during the life cycle. Following desiccation, we observed an extension in the larval longevity whereas the duration of the pupal and adult stages was significantly shortened. Alternately, feeding of 20-hydroxyecdysone apparently led to the restoration of the normal temporal pattern of development in the desiccated group. In spite of the desiccation-responsive heterochronic shifts in development, the overall lifespan post recovery remained almost unaltered among the desiccated and undesiccated groups suggesting plasticity in developmental control. This observation reminisces ‘canalization-like’ phenomenon that buffers alterations in the overall lifespan. We thus identified a desiccation-responsive period in the lifespan of D. melanogaster during which variations in ecdysone levels are capable to alter the temporal course of development. 相似文献
29.
Justin S. LaFountaine Leena Kumari Prasad Chris Brough Dave A. Miller James W. McGinity Robert O. WilliamsIII 《AAPS PharmSciTech》2016,17(1):120-132
Thermal processing technologies continue to gain interest in pharmaceutical manufacturing. However, the types and grades of polymers that can be utilized in common thermal processing technologies, such as hot-melt extrusion (HME), are often limited by thermal or rheological factors. The objectives of the present study were to compare and contrast two thermal processing methods, HME and KinetiSol® Dispersing (KSD), and investigate the influence of polymer type, polymer molecular weight, and drug loading on the ability to produce amorphous solid dispersions (ASDs) containing the model compound griseofulvin (GRIS). Dispersions were analyzed by a variety of imaging, solid-state, thermal, and solution-state techniques. Dispersions were prepared by both HME and KSD using polyvinylpyrrolidone (PVP) K17 or hydroxypropyl methylcellulose (HPMC) E5. Dispersions were only prepared by KSD using higher molecular weight grades of HPMC and PVP, as these could not be extruded under the conditions selected. Powder X-ray diffraction (PXRD) analysis showed that dispersions prepared by HME were amorphous at 10% and 20% drug load; however, it showed significant crystallinity at 40% drug load. PXRD analysis of KSD samples showed all formulations and drug loads to be amorphous with the exception of trace crystallinity seen in PVP K17 and PVP K30 samples at 40% drug load. These results were further supported by other analytical techniques. KSD produced amorphous dispersions at higher drug loads than could be prepared by HME, as well as with higher molecular weight polymers that were not processable by HME, due to its higher rate of shear and torque output. 相似文献
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