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621.
Lau Caspar Thygesen Niels Christian Hvidt Helle Ploug Hansen Andreas Hoff Lone Ross Christoffer Johansen 《Cancer epidemiology》2012,36(6):513-518
IntroductionAmerican Seventh-day Adventists have been reported to have lower cancer mortality and incidence than the general population. Adventists do not consume tobacco, alcohol or pork, and many adhere to a lacto-ovo-vegetarian lifestyle. Baptists discourage excessive use of alcohol and tobacco. In this study, we investigated whether the incidence of cancer in a large cohort of Danish Adventists and Baptists was different compared to the general Danish population.Material and methodsWe followed 11,580 Danish Adventists and Baptists in the nationwide Danish Cancer Registry, which contains information on cases of cancer for 1943–2008. Cancer incidence in the cohort was compared with that in the general Danish population as standardized incidence ratios (SIRs) with 95% confidence intervals (CIs), and within-cohort comparisons were made with a Cox model.ResultsLower cancer incidences were observed for both Seventh-day Adventist men (SIR, 66; 95% CI, 60–72) and women (85; 80–91). The same result was observed for Baptists although not as low. The differences were most pronounced for smoking-related cancers such as those of the buccal cavity and lung (SIR, 20; 13–30 for Seventh-day Adventist men and 33; 22–49 for Seventh-day Adventist women). The incidences of other lifestyle-related cancers, such as of stomach, rectum, liver and cervix, were also decreased. In general, the SIRs were lower for men than for women, and Adventists had lower hazard rates than Baptists.DiscussionOur findings point to the benefits of compliance with public health recommendations and indicate that lifestyle changes in the population might change the cancer risks of individuals. 相似文献
622.
Lange Sofie C. Bak Lasse K. Waagepetersen Helle S. Schousboe Arne Norenberg Michael D. 《Neurochemical research》2012,37(11):2569-2588
Neurochemical Research - During the past few decades of astrocyte research it has become increasingly clear that astrocytes have taken a central position in all central nervous system activities.... 相似文献
623.
Nanna Johnsen Aimi D.M. Hamilton Anne Sofie Greve Mette G. Christensen Jacob R. Therkildsen Julia Wehmller Marianne Skals Helle A. Praetorius 《Cellular microbiology》2019,21(6)
α‐Haemolysin (HlyA) from uropathogenic Escherichia coli has been demonstrated to be a significant virulence factor for ascending urinary tract infections. Once the E. coli reach the well‐vascularised kidneys, there is a high risk of bacteraemia and a subsequent septic host response. Despite this, HlyA has the potential to accelerate the host response both directly and via its ability to facilitate adenosine triphosphate release from cells. It has not been settled whether HlyA aggravates bacteraemia into a septic state. To address this, we used an E. coli strain in a model of acute urosepsis that was either transfected with a plasmid containing the full HlyA operon or one with deletion in the HlyA gene. Here, we show that HlyA accelerates the host response to E. coli in the circulation. Mice exposed to HlyA‐producing E. coli showed massively increased proinflammatory cytokines, a substantial fall in circulating thrombocytes, extensive haematuria, and intravascular haemolysis. This was not seen in mice exposed to either E. coli that do not secrete HlyA or vehicle controls. Consistent with the massive host response to the bacteria, the mice exposed to HlyA‐producing E. coli died exceedingly early, whereas mice exposed to E. coli without HlyA production and vehicle controls survived the entire observation period. These data allow us to conclude that HlyA is a virulence factor that accelerates a state of bacteraemia into fulminant sepsis in a mouse model. 相似文献
624.
Siv Nam Khang Hoff Helle T. Baalsrud Ave Tooming‐Klunderud Morten Skage Todd Richmond Gregor Obernosterer Reza Shirzadi Ole Kristian Trresen Kjetill S. Jakobsen Sissel Jentoft 《Molecular ecology resources》2019,19(1):245-259
Combining high‐throughput sequencing with targeted sequence capture has become an attractive tool to study specific genomic regions of interest. Most studies have so far focused on the exome using short‐read technology. These approaches are not designed to capture intergenic regions needed to reconstruct genomic organization, including regulatory regions and gene synteny. Here, we demonstrate the power of combining targeted sequence capture with long‐read sequencing technology for comparative genomic analyses of the haemoglobin (Hb) gene clusters across eight species separated by up to 70 million years. Guided by the reference genome assembly of the Atlantic cod (Gadus morhua) together with genome information from draft assemblies of selected codfishes, we designed probes covering the two Hb gene clusters. Use of custom‐made barcodes combined with PacBio RSII sequencing led to highly continuous assemblies of the LA (~100 kb) and MN (~200 kb) clusters, which include syntenic regions of coding and intergenic sequences. Our results revealed an overall conserved genomic organization of the Hb genes within this lineage, yet with several, lineage‐specific gene duplications. Moreover, for some of the species examined, we identified amino acid substitutions at two sites in the Hbb1 gene as well as length polymorphisms in its regulatory region, which has previously been linked to temperature adaptation in Atlantic cod populations. This study highlights the use of targeted long‐read capture as a versatile approach for comparative genomic studies by generation of a cross‐species genomic resource elucidating the evolutionary history of the Hb gene family across the highly divergent group of codfishes. 相似文献
625.
626.
Bak LK Waagepetersen HS Melø TM Schousboe A Sonnewald U 《Neurochemical research》2007,32(4-5):671-680
Glutamate metabolism was studied in co-cultures of mouse cerebellar neurons (predominantly glutamatergic) and astrocytes.
One set of cultures was superfused (90 min) in the presence of either [U-13C]glucose (2.5 mM) and lactate (1 mM) or [U-13C]lactate (1 mM) and glucose (2.5 mM). Other sets of cultures were incubated in medium containing [U-13C]lactate (1 mM) and glucose (2.5 mM) for 4 h. Regardless of the experimental conditions cell extracts were analyzed using
mass spectrometry and nuclear magnetic resonance spectroscopy. 13C labeling of glutamate was much higher than that of glutamine under all experimental conditions indicating that acetyl-CoA
from both lactate and glucose was preferentially metabolized in the neurons. Aspartate labeling was similar to that of glutamate,
especially when [U-13C]glucose was the substrate. Labeling of glutamate, aspartate and glutamine was lower in the cells incubated with [U-13C]lactate. The first part of the pyruvate recycling pathway, pyruvate formation, was detected in singlet and doublet labeling
of alanine under all experimental conditions. However, full recycling, detectable in singlet labeling of glutamate in the
C-4 position was only quantifiable in the superfused cells both from [U-13C]glucose and [U-13C]lactate. Lactate and alanine were mostly uniformly labeled and labeling of alanine was the same regardless of the labeled
substrate present and higher than that of lactate when superfused in the presence of [U-13C]glucose. These results show that metabolism of pyruvate, the precursor for lactate, alanine and acetyl-CoA is highly compartmentalized.
Special issue dedicated to John P. Blass. 相似文献
627.
Salcedo Claudia Wagner Antonie Andersen Jens V. Vinten Kasper Tore Waagepetersen Helle S. Schousboe Arne Freude Kristine K. Aldana Blanca I. 《Neurochemical research》2021,46(10):2676-2686
Neurochemical Research - Alterations in neurotransmitter homeostasis, primarily of glutamate and GABA, is strongly implicated in the pathophysiology of Alzheimer’s disease (AD). Homeostasis... 相似文献
628.
González Matías Nicolás Massa Gabriela Alejandra Andersson Mariette Décima Oneto Cecilia Andrea Turesson Helle Storani Leonardo Olsson Niklas Fält Ann-Sofie Hofvander Per Feingold Sergio Enrique 《Plant Cell, Tissue and Organ Culture》2021,145(2):291-305
Plant Cell, Tissue and Organ Culture (PCTOC) - Delivery of the CRISPR/Cas9 components to the plant cells is a key step in its application as a genome editing tool. Here, we compared... 相似文献
629.
Katri Korpela Pekka Helle Heikki Henttonen Erkki Korpim?ki Esa Koskela Otso Ovaskainen Hannu Pieti?inen Janne Sundell Jari Valkama Otso Huitu 《Proceedings. Biological sciences / The Royal Society》2014,281(1797)
The cyclic population dynamics of vole and predator communities is a key phenomenon in northern ecosystems, and it appears to be influenced by climate change. Reports of collapsing rodent cycles have attributed the changes to warmer winters, which weaken the interaction between voles and their specialist subnivean predators. Using population data collected throughout Finland during 1986–2011, we analyse the spatio-temporal variation in the interactions between populations of voles and specialist, generalist and avian predators, and investigate by simulations the roles of the different predators in the vole cycle. We test the hypothesis that vole population cyclicity is dependent on predator–prey interactions during winter. Our results support the importance of the small mustelids for the vole cycle. However, weakening specialist predation during winters, or an increase in generalist predation, was not associated with the loss of cyclicity. Strengthening of delayed density dependence coincided with strengthening small mustelid influence on the summer population growth rates of voles. In conclusion, a strong impact of small mustelids during summers appears highly influential to vole population dynamics, and deteriorating winter conditions are not a viable explanation for collapsing small mammal population cycles. 相似文献
630.
Nhu-Mai Tran Murielle Dufresne Fran?ois Helle Thomas Walter Hoffmann Catherine Fran?ois Etienne Brochot Patrick Paullier Cécile Legallais Gilles Duverlie Sandrine Castelain 《PloS one》2014,9(10)
Cell microencapsulation in alginate hydrogel has shown interesting applications in regenerative medicine and the biomedical field through implantation of encapsulated tissue or for bioartificial organ development. Although alginate solution is known to have low antiviral activity, the same property regarding alginate gel has not yet been studied. The aim of this work is to investigate the potential protective effect of alginate encapsulation against hepatitis C virus (HCV) infection for a hepatic cell line (HuH-7) normally permissive to the virus. Our results showed that alginate hydrogel protects HuH-7 cells against HCV when the supernatant was loaded with HCV. In addition, alginate hydrogel blocked HCV particle release out of the beads when the HuH-7 cells were previously infected and encapsulated. There was evidence of interaction between the molecules of alginate hydrogel and HCV, which was dose- and incubation time-dependent. The protective efficiency of alginate hydrogel towards HCV infection was confirmed against a variety of viruses, whether or not they were enveloped. This promising interaction between an alginate matrix and viruses, whose chemical mechanisms are discussed, is of great interest for further medical therapeutic applications based on tissue engineering. 相似文献