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Valentina Isetta Josep M. Montserrat Raquel Santano Alison J. Wimms Dinesh Ramanan Holger Woehrle Daniel Navajas Ramon Farré 《PloS one》2016,11(3)
Bench testing is a useful method to characterize the response of different automatic positive airway pressure (APAP) devices under well-controlled conditions. However, previous models did not consider the diversity of obstructive sleep apnea (OSA) patients’ characteristics and phenotypes. The objective of this proof-of-concept study was to design a new bench test for realistically simulating an OSA patient’s night, and to implement a one-night example of a typical female phenotype for comparing responses to several currently-available APAP devices. We developed a novel approach aimed at replicating a typical night of sleep which includes different disturbed breathing events, disease severities, sleep/wake phases, body postures and respiratory artefacts. The simulated female OSA patient example that we implemented included periods of wake, light sleep and deep sleep with positional changes and was connected to ten different APAP devices. Flow and pressure readings were recorded; each device was tested twice. The new approach for simulating female OSA patients effectively combined a wide variety of disturbed breathing patterns to mimic the response of a predefined patient type. There were marked differences in response between devices; only three were able to overcome flow limitation to normalize breathing, and only five devices were associated with a residual apnea-hypopnea index of <5/h. In conclusion, bench tests can be designed to simulate specific patient characteristics, and typical stages of sleep, body position, and wake. Each APAP device behaved differently when exposed to this controlled model of a female OSA patient, and should lead to further understanding of OSA treatment. 相似文献
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N. Maaranen C. Stantis A. Kharobi S. Zakrzewski H. Schutkowski C. Doumet-Serhal 《American journal of physical anthropology》2023,182(3):428-439
Objectives
The Levantine Middle Bronze Age (MBA, circa 2000–1500 BCE) marks a period of increased trade and regional interaction, spurred on by technological developments. In light of previous research exhibiting limited mobility in Sidon, further investigation was conducted using biodistance analysis to understand local population history and site development.Materials and Methods
Dental nonmetric traits, a proxy for genetic information, were explored using ASUDAS on a sub-sample of primary inhumations (n = 35). The biodistance matrix was generated using Gower distance measures, and further tested using PERMDISP, PERMANOVA, Mantel test and hierarchical cluster analysis. The data was also contrasted to 87Sr/86Sr and δ18O as well as δ13C and δ15N values.Results
There were no significant diachronic differences in isotopes values, and there was biological continuity (n = 35, Mantel test r = 0.11, p = 0.02, comparing local phases and biodistance). The analysis also suggested of a sub-group of individuals with biological proximity shared a more limited range of mobility and dietary habits.Conclusions
The isotopes (87Sr/86Sr, δ18O, δ13C, δ15N) and biodistance analysis conducted on the Sidon College site skeletal assemblage exhibits stability and continuity of the people, despite the site's increasing role in the maritime network. This continuity may have been a key factor in Sidon's success, allowing it to accumulate wealth and resources for centuries to come.5.
Mitosis is the key event of the cell cycle during which the sister chromatids are segregated onto two daughter cells. It is well established that abrogation of the normal mitotic progression is a highly efficient concept for anti‐cancer treatment. In fact, various drugs that target microtubules and thus interfere with the function of the mitotic spindle are in clinical use for the treatment of various human malignancies for many years. However, since microtubule inhibitors not only target proliferating cells severe side effects limit their use. Therefore, the identification of novel mitotic drug targets other than microtubules have gained recently much attention. This review will summarize the latest developments on the identification and clinical evaluation of novel mitotic drug targets and will introduce novel concepts for chemotherapy that are based on recent progress in our understanding how mitotic progression is regulated and how anti‐mitotic drugs induce tumor cell death. J. Cell. Biochem. 111: 258–265, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
6.
H. Schutkowski 《International Journal of Anthropology》1987,2(4):347-352
Facing the requirements of refined paleodemographical analyses, the access to the early ontogenetic sex ratio of skeletal
populations is an important feature. Using raw data provided byFazekas & Kosa (1978) for a sample of known sex, discriminant functions are derived from hip and thigh bone dimensions that allow an almost
unbiased classification of more than 70% of fetal and neonate individuals. 相似文献
7.
The cis/trans interconversion of Glt-Ala-Ala-Pro-Phe-4-nitroanilide and Glt-Ala-Gly-Pro-Phe-4-nitroanilide was studied both enzymatically and nonenzymatically by measuring kinetic β-deuterium isotope effects. The hydrogen atom at the α-carbon atom of the Xaa residue within the Xaa-Pro moiety was substituted by deuterium. In the nonenzymatic case the transition state of rotation is reflected by kH/kD > 1. When catalysed by 17 kDa PPIase the same bond rotation is characterized by kH/kD < 1. This suggests a covalent mechanism of catalysis which involves an approximately tetravalent carbon of the prolyl imidic bond for the transition state of reaction. 相似文献
8.
H Schutkowski 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》1989,47(1):1-9
In connection with increasing theory-bound investigations in prehistoric anthropology age and sex diagnosis of children's skeletons is gaining importance. Developmental stages of the tympanic plate are introduced as an additional criterion for ageing infants. Discriminant functions derived from ilium and femur measurements allow preliminary access towards a metric sexual diagnosis of fetal and neonate individuals. 相似文献
9.
Martin Poot Julia Koehler Peter S. Rabinovitch Holger Hoehn Jean H. Priest 《Human genetics》1990,84(3):258-262
Summary BrdU-Hoechst flow cytometry was used to investigate the effects of DNA hypomethylation, induced by treatment with 5-azacytidine (5AC), on cell proliferation. When human fibroblast-like cells derived from skin and amniotic fluid were exposed to 5AC during three successive cell cycles, their clone-forming ability was diminished after removal of the drug. Treated cells were rendered quiescent by culture with low serum in the absence of the drug. Upon serum stimulation, they showed a diminished fraction of proliferating cells, which exhibited a prolonged transit through the S and G2 phase of the cell cycle, and a permanent arrest within the G2 compartment. This pattern of disturbed cell proliferation may in part explain the changes in replication banding pattern reported in the literature. Cytogenetic analysis of 5AC-treated cells revealed numerous endomitoses and tetraploid metaphases indicating a disturbed chromosome cycle in association with these cell kinetic perturbations. 相似文献
10.
Ahmed M. Abouzid Thomas Frischmuth Holger Jeske 《Molecular & general genetics : MGG》1988,212(2):252-258
Summary The putative replicative form of the abutilon mosaic virus (AbMV), a geminivirus, was purified from infected plants. It was shown to consist of a bipartite genome of 2660 and 2640 bp. This double-stranded DNA has a closed or relaxed circular conformation and part of it is packed in nucleoprotein complexes with a chromatin-like structure. Similarities between the geminiviruses and the animal simian virus 40 are discussed against this back-ground.Cloning was performed under L2/B1 conditions according to the licence of the ZKBS 1526/1This article is based on a doctoral study by A.A. and T.F. in the Faculty of Biology, University of Hamburg 相似文献