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881.
David W. Tscholl Mona Weiss Lucas Handschin Donat R. Spahn Christoph B. Nöthiger 《BMC anesthesiology》2018,18(1):188
Background
A new patient monitoring technology called Visual Patient, which transforms numerical and waveform data into a virtual model (an avatar) of the monitored patient, has been shown to improve the perception of vital signs compared to conventional patient monitoring. In order to gain a deeper understanding of the opinions of potential future users regarding the new technology, we have analyzed the answers of two large groups of anesthetists using two different study methods.Methods
First, we carried out a qualitative analysis guided by the “consolidated criteria for reporting qualitative research” checklist. For this analysis, we interviewed 128 anesthesiologists, asking: “Where do you see advantages in Visual Patient monitoring?” and afterward identified major and minor themes in their answers. In a second study, an online survey with 38 anesthesiologists at two different institutions, we added a quantitative part in which anesthesiologists rated statements based on the themes identified in the prior analysis on an ordinal rating scale.Results
We identified four high-level themes: “quick situation recognition,” “intuitiveness,” “unique design characteristics,” and “potential future uses,” and eight subthemes.The quantitative questions raised for each major theme were: 1. “The Visual Patient technology enabled me to get a quick overview of the situation.” (63% of the participants agreed or very much agreed to this statement). 2. “I found the Visual Patient technology to be intuitive and easy to learn.” (82% agreed or very much agreed to this statement). 3. “The visual design features of the Visual Patient technology (e.g., the avatar representation) are not helpful for patient monitoring.” (11% agreed to this statement). 4. “I think the Visual Patient technology might be helpful for non-monitor experts (e.g., surgeons) in the healthcare system.” (53% of the participants agreed or strongly agreed).Conclusion
This mixed method study provides evidence that the included anesthesiologists considered the new avatar-based technology to be intuitive and easy to learn and that the technology enabled them to get an overview of the situation quickly. Only a few users considered the avatar presentation to be unhelpful for patient monitoring and about half think it might be useful for non-experts.882.
Davar Khodadadi Reza Gharakhanlou Naser Naghdi Mona Salimi Mohammad Azimi Atabak Shahed Soomaayeh Heysieattalab 《Neurochemical research》2018,43(8):1561-1574
Aggregated amyloid beta (Aβ) peptides are believed to play a decisive role in the pathology of Alzheimer’s disease (AD). Previous evidence suggested that exercise contributes to the improvement of cognitive decline and slows down pathogenesis of AD; however, the exact mechanisms for this have not been fully understood. Here, we evaluated the effect of a 4-week moderate treadmill exercise on spatial memory via central and peripheral Aβ clearance mechanisms following developed AD-like neuropathology induced by intra-hippocampal Aβ1–42 injection in male Wistar rats. We found Aβ1–42-treated animals showed spatial learning and memory impairment which was accompanied by increased levels of amyloid plaque load and soluble Aβ1–42 (sAβ1–42), decreased mRNA and protein expression of neprilysin (NEP), insulin degrading enzyme (IDE) and low-density lipoprotein receptor-related protein-1 (LRP-1) in the hippocampus. Aβ1–42-treated animals also exhibited a higher level of sAβ1–42 and a lower level of soluble LRP-1 (sLRP-1) in plasma, as well as a decreased level of LRP-1 mRNA and protein content in the liver. However, exercise training improved the spatial learning and memory deficits, reduced both plaque load and sAβ1–42 levels, and up-regulated expression of NEP, IDE, and LRP-1 in the hippocampus of Aβ1–42-treated animals. Aβ1–42-treated animals subjected to treadmill exercise also revealed decreased levels of sAβ1–42 and increased levels of sLRP-1 in plasma, as well as increased levels of LRP-1 mRNA and protein in the liver. In conclusion, our findings suggest that exercise-induced improvement in both of central and peripheral Aβ clearance are likely involved in ameliorating spatial learning and memory deficits in an animal model of AD. Future studies need to determine their relative contribution. 相似文献
883.
884.
15N abundance of surface soils,roots and mycorrhizas in profiles of European forest soils 总被引:6,自引:0,他引:6
Peter Högberg Lars Högbom Helga Schinkel Mona Högberg Christian Johannisson Håkan Wallmark 《Oecologia》1996,108(2):207-214
15N natural abundances of soil total N, roots and mycorrhizas were studied in surface soil profiles in coniferous and broadleaved forests along a transect from central to northern Europe. Under conditions of N limitation in Sweden, there was an increase in 15N of soil total N of up to 9% from the uppermost horizon of the organic mor layer down to the upper 0–5 cm of the mineral soil. The 15N of roots was only slightly lower than that of soil total N in the upper organic horizon, but further down roots were up to 5% depleted under such conditions. In experimentally N-enriched forest in Sweden, i.e. in plots which have received an average of c. 100 kg N ha–1 year–1 for 20 years and which retain less than 50% of this added N in the stand and the soil down to 20 cm depth, and in some forests in central Europe, the increase in 15N with depth in soil total N was smaller. An increase in 15N of the surface soil was even observed on experimentally N-enriched plots, although other data suggest that the N fertilizer added was depleted in15N. In such cases roots could be enriched in15N relative to soil total N, suggesting that labelling of the surface soil is via the pathway: — available pools of N-plant N-litter N. Under N-limiting conditions roots of different species sampled from the same soil horizon showed similar 15N. By contrast, in experimentally N-enriched forest 15N of roots increased in the sequence: ericaceous dwarf shrubs15N enriched compounds in fungal material, which could contribute to explain the observed 15N profiles if fungal material is enriched, because it is a precursor of stable organic matter and recalcitrant N. This could act in addition to the previous explanation of the isotopically lighter soil surface in forests: plant uptake of 15N-depleted N and its redeposition onto the soil surface by litter-fall. 相似文献
885.
Eva Agurell Hakan Cederberg Mona Hedenskog Ulf Rannug 《Molecular & general genetics : MGG》1994,242(2):137-144
To study chemically induced DNA amplifications we used the haploid Saccharomyces cerevisiae strain TR(MS1)-1 carrying an integrated chromosomal copy of the human minisatellite, MS1. Chemicals with different mechanisms of action were tested in this strain: methyl methanesulphonate, ethylene oxide (EO), propylene oxide (PO), camptothecin, 2,3,7,8-tetrachlorodibenso-p-dioxin (TCDD) and reserpine. No increase in frequency of new MS1 length alleles was seen with any of the tested chemicals relative to the spontaneous frequency of approximately 30%. EO and TCDD induced changes in the amplification spectrum, i.e. the frequency distribution of MS1 length alleles longer than the original 1.42 kb allele. PO and camptothecin increased the frequency of plasmid pop-out events. It seems likely that several mechanisms e.g. unequal exchanges, replication slippage and loop formation leading to deletion of a ring of tandem repeats, are involved in the generation of new MS1 length alleles. A loop-forming deletion mechanism is supported by the tendency to multimodality shown in the deamplification (loss of repeat units) spectra, i.e. the frequency distribution of new MS1 length alleles shorter than the original allele. EO and TCDD induced longer MS1 length alleles as compared to the control. The frequent generation of new MS1 length alleles in this haploid yeast strain further demonstrates the instability of such sequences and their possible relevance to genetic toxicology and the mechanisms of induction of cancer as well as other diseases. This study is a first step towards the development of an assay for DNA amplification without the use of a selective agent. 相似文献
886.
Competition for DNA steroid response elements as a possible mechanism for neuroendocrine integration
Donald W. Pfaff Mona M. Freidin X. Sharon Wu-Peng Jun Yin Yuan-Shan Zhu 《The Journal of steroid biochemistry and molecular biology》1994,49(4-6):373-379
For the analysis of a simple steroid-dependent mating behavior, careful response definition, complete neural circuit delineation and placement of estrogen-responsive cells within this circuit have been accomplished. Molecular studies of two relevant genes have emphasized DNA/RNA hybridization assays nd DNA binding techniques. For both the rat preproenkephalin gene and the gene for the progesterone receptor, a strong induction by estrogen, tissue specificity of expression and a sex difference in regulation are prominent phenomena. On the rat preproenkephalin promoter, estrogen (ER) and thyroid receptors may compete for a DNA binding site. Likewise, progesterone (PR) and glucocorticoid receptors may compete for the same sites. On the rat PR gene, interactions between ER and AP-1 binding proteins are of special interest. Such interactions could underlay competitions and synergies between steroid hormones and neurally signalled events in the environment. 相似文献
887.
Busse M Feta A Presto J Wilén M Grønning M Kjellén L Kusche-Gullberg M 《The Journal of biological chemistry》2007,282(45):32802-32810
The exostosin (EXT) family of genes encodes glycosyltransferases involved in heparan sulfate biosynthesis. Five human members of this family have been cloned to date: EXT1, EXT2, EXTL1, EXTL2, and EXTL3. EXT1 and EXT2 are believed to form a Golgi-located hetero-oligomeric complex that catalyzes the chain elongation step in heparan sulfate biosynthesis, whereas the EXTL proteins exhibit overlapping glycosyl-transferase activities in vitro, so that it is not apparent what reactions they catalyze in vivo. We used gene-silencing strategies to investigate the roles of EXT1, EXT2, and EXTL3 in heparan sulfate chain elongation. Small interfering RNAs (siRNAs) directed against the human EXT1, EXT2, or EXTL3 mRNAs were introduced into human embryonic kidney 293 cells. Compared with cells transfected with control siRNA, those transfected with EXT1 or EXT2 siRNA synthesized shorter heparan sulfate chains, and those transfected with EXTL3 siRNA synthesized longer chains. We also generated human cell lines overexpressing the EXT proteins. Overexpression of EXT1 resulted in increased HS chain length, which was even more pronounced in cells coexpressing EXT2, whereas overexpression of EXT2 alone had no detectable effect on heparan sulfate chain elongation. Mutations in either EXT1 or EXT2 are associated with hereditary multiple exostoses, a human disorder characterized by the formation of cartilage-capped bony outgrowths at the epiphyseal growth plates. To further investigate the role of EXT2, we generated human cell lines overexpressing mutant EXT2. One of the mutations, EXT2-Y419X, resulted in a truncated protein. Interestingly, the capacity of wild type EXT2 to enhance HS chain length together with EXT1 was not shared by the EXT2-Y419X mutant. 相似文献
888.
Both the photosynthetic and heterotrophic forms of the only known marine benthic (sand-dwelling) species of Polykrikos, namely P. lebourae, were investigated using light and electron microscopy and molecular phylogenetic analyses. The pseudocolonies usually contained eight integrated zooids and two nuclei. Pseudocolonies consisting of four or five zooids and one nucleus were observed for the first time for this species; some of these reduced pseudocolonies contained plastids, while others were heterotrophic and contained taeniocyst-nematocyst complexes. The ultrastructure of the plastids in P. lebourae did not conform to the organization of thylakoids and enveloping membranes present in the peridinin-containing plastids of other photosynthetic dinoflagellates (i.e. stacks of 3 thylakoids and 3 outer membranes). Instead, the plastids in P. lebourae had thylakoids arranged in pairs and appeared to be enveloped by only two membranes. Molecular phylogenetic data using small subunit rDNA demonstrated that the photosynthetic and heterotrophic forms of P. lebourae represent two distinct clades. The more inclusive clade containing both forms of P. lebourae was most closely related to heterotrophic polykrikoids, namely P. kofoidii. These results led us to conclude that the photosynthetic and heterotrophic forms of P. lebourae are in fact two distinct lineages, and the heterotrophic form is described here as Polykrikos herdmanae n. sp. 相似文献
889.
In the last few decades, several growth factors were identified in the testis of various mammalian species. Growth factors
are shown to promote cell proliferation, regulate tissue differentiation, and modulate organogenesis. In the present investigation
we have studied the localization of EGF and EGFR in the adult bovine testis by means of immunohistochemical method. Our results
demonstrated that EGF and EGFR were localized solely to the bovine testicular germ cells (spermatogonia, spermatocytes, and
round spermatids). In contrast, the somatic testicular cells (i.e., Sertoli, Leydig, and myofibroblast cells) exhibited no
staining affinity. EGF and EGFR were additionally detected in the epithelial lining of straight tubules and rete testis. Interestingly,
the distribution of EGF and EGFR in the germ cells was mainly dependent upon the cycle of the seminiferous epithelium since
their localization appeared to be preponderant during the spermatogonia proliferation and during the meiotic and spermiogenic
processes. In conclusion, such findings may suggest that EGF and EGFR are important paracrine and/or autocrine regulators
of spermatogenesis in bovine. 相似文献
890.
Ali Taghizadeh Kermani Sare Hosseini Azar Fanipakdel Mona Joudi Mashhad Kambiz Akhavan Rezayat Mahdi Zardadi Arezoo Gholami Seyed Alireza Javadinia Gordon A. Ferns Amir Avan 《Journal of cellular physiology》2019,234(4):4191-4199
The current treatment approaches for esophageal cancer are associated with poor survival, and there are ongoing efforts to find new and more effective therapeutic strategies. There are several reports on the antitumoral effects of low-molecular-weight heparins (LMWHs). We have assessed the possible survival benefit of LMWHs in esophageal malignancies. This was a randomized, single-blind, multicenter, Phase II clinical trial on nonmetastatic esophageal cancer candidate for neoadjuvant chemoradiotherapy. Patients were randomly assigned to the chemoradiotherapy-only arm or chemoradiotherapy plus enoxaparin arm using 1:1 allocation. Radiotherapy was delivered in 1.8-Gy daily fractions to a dose of 50.4 Gy in both groups. Paclitaxel 50 mg/m2 and carboplatin (AUC 2) were administered weekly, concurrent with radiotherapy. In the intervention group, patients received enoxaparin (40 mg) and chemoradiation daily. 4–6 weeks after treatment, all patients underwent esophagectomy. After a median follow up of 7 months, estimated 1 year disease-free survival (DFS) in the intervention group was 78.9% and was 70% in the control groups ( p = 0.5). Toxicity from the experimental treatment was minimal, and there were no treatment-related deaths. A pathologically complete response in intervention and control group was 64.8% and 62.5%, respectively ( p = 0.9). There was a nonsignificant trend toward improved survival by the addition of enoxaparin to the concurrent chemoradiotherapy regimen. However, 1 y DFS of both groups were high as expected. A longer follow-up and a larger sample size are required. 相似文献