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61.
Using ontologies to describe mouse phenotypes 总被引:1,自引:1,他引:0
The mouse is an important model of human genetic disease. Describing phenotypes of mutant mice in a standard, structured manner that will facilitate data mining is a major challenge for bioinformatics. Here we describe a novel, compositional approach to this problem which combines core ontologies from a variety of sources. This produces a framework with greater flexibility, power and economy than previous approaches. We discuss some of the issues this approach raises. 相似文献
62.
Olfactory sensitivity in tsetse flies: a daily rhythm 总被引:3,自引:0,他引:3
The diurnal tsetse Glossina morsitans morsitans bites especially in early
morning and late afternoon; around midday feeding is at a low. In
laboratory apparatus that measures the amount of locomotion under constant
conditions over the photophase, the flies display a similar patterning of
activity levels. The profile of daily rhythms for G. morsitans reported in
the literature includes a number of motor and sensory motor systems that
fluctuate cophasically. Lacking is a study on the patterning of the senses'
response levels. In this paper we present the first instance of a daily
modulation in the sense of smell. We stimulated the antennae with
concentration series of host-derived odours and measured the spiking rate
of cells at different times during the photophase. The
concentration-response curves suggest that the sensitivity of antennal
olfactory cells flows in parallel with the other daily rhythms. This was
also reflected in electroantennograms (EAGs). The electroantennography was
extended to G. fuscipes fuscipes, whose level of spontaneous locomotor
activity--instead of following a U- shaped pattern--rises gradually over
the photophase. Again, the EAGs appeared to parallel the species' locomotor
activity. What we believe happens is that the organism tones down the
sensitivity of its odour receptors during periods of anticipated inactivity
for reasons of economy.
相似文献
63.
Nocardia corallina B276 cells were immobilized by emulsification with liquid paraffin and an antifoam agent at room temperature. The immobilized cells were studied for their ability to carry out the formation of propylene oxide from propylene and oxygen. The evaluations were done with the cells in a bubble-type reactor with a continuous gas feed of 5% propylene and 11.6-95% oxygen, with the balance nitrogen. By using liquid paraffin and antifoam, both the epoxidation activity and the stability were improved, especially for the P-1-200 strain, over that for nonimmobilized cells. The N. corallina cells showed an apparent preference for a hydrophobic, as compared to a hydrophilic, environment. The propylene-oxide-forming activity of the immobilized cells was higher at 40 than at 30 degrees C reactor temperature and with 20% (versus 95%) oxygen in the feed. The stability was markedly better at 30 degrees C and with 20% oxygen. High gas flowrates gave increased apparent activity probably because of less resistance to substrate mass transfer. The effects of pH were minor. The role of glucose as the energy source for regeneration of cofactors for the monooxygenase system also is discussed. 相似文献
64.
Since the publication of our article (Roth, Gonnet, and Dessimoz: BMC Bioinformatics 2008 9: 518), we have noticed several errors, which we correct in the following. 相似文献
65.
Valentina C Sladky Katja Knapp Tamas G Szabo Vincent Z Braun Laura Bongiovanni Hilda van den Bos Diana CJ Spierings Bart Westendorp Ana Curinha Tatjana Stojakovic Hubert Scharnagl Gerald Timelthaler Kaoru Tsuchia Matthias Pinter Georg Semmler Floris Foijer Alain de Bruin Thomas Reiberger Nataliya RohrUdilova Andreas Villunger 《EMBO reports》2020,21(12)
Polyploidization frequently precedes tumorigenesis but also occurs during normal development in several tissues. Hepatocyte ploidy is controlled by the PIDDosome during development and regeneration. This multi‐protein complex is activated by supernumerary centrosomes to induce p53 and restrict proliferation of polyploid cells, otherwise prone for chromosomal instability. PIDDosome deficiency in the liver results in drastically increased polyploidy. To investigate PIDDosome‐induced p53‐activation in the pathogenesis of liver cancer, we chemically induced hepatocellular carcinoma (HCC) in mice. Strikingly, PIDDosome deficiency reduced tumor number and burden, despite the inability to activate p53 in polyploid cells. Liver tumors arise primarily from cells with low ploidy, indicating an intrinsic pro‐tumorigenic effect of PIDDosome‐mediated ploidy restriction. These data suggest that hyperpolyploidization caused by PIDDosome deficiency protects from HCC. Moreover, high tumor cell density, as a surrogate marker of low ploidy, predicts poor survival of HCC patients receiving liver transplantation. Together, we show that the PIDDosome is a potential therapeutic target to manipulate hepatocyte polyploidization for HCC prevention and that tumor cell density may serve as a novel prognostic marker for recurrence‐free survival in HCC patients. 相似文献
66.
Sonja Melman Ellen NC Schoorel Carmen Dirksen Anneke Kwee Luc Smits Froukje de Boer Madelaine Jonkers Mallory D Woiski Ben Willem J Mol Johannes PR Doornbos Harry Visser Anjoke JM Huisjes Martina M Porath Friso MC Delemarre Simone MI Kuppens Robert Aardenburg Ivo MA Van Dooren Francis PJM Vrouenraets Frans TH Lim Gunilla Kleiverda Paulien CM van der Salm Karin de Boer Marko J Sikkema Jan G Nijhuis Rosella PMG Hermens Hubertina CJ Scheepers 《Implementation science : IS》2013,8(1):1-8
Background
Caesarean section (CS) rates are rising worldwide. In the Netherlands, the most significant rise is observed in healthy women with a singleton in vertex position between 37 and 42 weeks gestation, whereas it is doubtful whether an improved outcome for the mother or her child was obtained. It can be hypothesized that evidence-based guidelines on CS are not implemented sufficiently. Therefore, the present study has the following objectives: to develop quality indicators on the decision to perform a CS based on key recommendations from national and international guidelines; to use the quality indicators in order to gain insight into actual adherence of Dutch gynaecologists to guideline recommendations on the performance of a CS; to explore barriers and facilitators that have a direct effect on guideline application regarding CS; and to develop, execute, and evaluate a strategy in order to reduce the CS incidence for a similar neonatal outcome (based on the information gathered in the second and third objectives).Methods
An independent expert panel of Dutch gynaecologists and midwives will develop a set of quality indicators on the decision to perform a CS. These indicators will be used to measure current care in 20 hospitals with a population of 1,000 women who delivered by CS, and a random selection of 1,000 women who delivered vaginally in the same period. Furthermore, by interviewing healthcare professionals and patients, the barriers and facilitators that may influence the decision to perform a CS will be measured. Based on the results, a tailor-made implementation strategy will be developed and tested in a controlled before-and-after study in 12 hospitals (six intervention, six control hospitals) with regard to effectiveness, experiences, and costs.Discussion
This study will offer insight into the current CS care and into the hindering and facilitating factors influencing obstetrical policy on CS. Furthermore, it will allow definition of patient categories or situations in which a tailor-made implementation strategy will most likely be meaningful and cost effective, without negatively affecting the outcome for mother and child.Trial registration
http://www.clinicaltrials.gov: NCT01261676 相似文献67.
Lonneke Smeding Jan Willem Kuiper Frans B Pl?tz Martin CJ Kneyber AB Johan Groeneveld 《Respiratory research》2013,14(1):92
Background
Mechanical ventilation (MV) may cause ventilator-induced lung injury (VILI) and may thereby contribute to fatal multiple organ failure. We tested the hypothesis that injurious MV of lipopolysaccharide (LPS) pre-injured lungs induces myocardial inflammation and further dysfunction ex vivo, through calcium (Ca2+)-dependent mechanism.Materials and methods
N = 35 male anesthetized and paralyzed male Wistar rats were randomized to intratracheal instillation of 2 mg/kg LPS or nothing and subsequent MV with lung-protective settings (low tidal volume (Vt) of 6 mL/kg and 5 cmH2O positive end-expiratory pressure (PEEP)) or injurious ventilation (high Vt of 19 mL/kg and 1 cmH2O PEEP) for 4 hours. Myocardial function ex vivo was evaluated in a Langendorff setup and Ca2+ exposure. Key mediators were determined in lung and heart at the mRNA level.Results
Instillation of LPS and high Vt MV impaired gas exchange and, particularly when combined, increased pulmonary wet/dry ratio; heat shock protein (HSP)70 mRNA expression also increased by the interaction between LPS and high Vt MV. For the heart, C-X-C motif ligand (CXCL)1 and Toll-like receptor (TLR)2 mRNA expression increased, and ventricular (LV) systolic pressure, LV developed pressure, LV +dP/dtmax and contractile responses to increasing Ca2+ exposure ex vivo decreased by LPS. High Vt ventilation aggravated the effects of LPS on myocardial inflammation and dysfunction but not on Ca2+ responses.Conclusions
Injurious MV by high Vt aggravates the effects of intratracheal instillation of LPS on myocardial dysfunction, possibly through enhancing myocardial inflammation via pulmonary release of HSP70 stimulating cardiac TLR2, not involving Ca2+ handling and sensitivity. 相似文献68.
69.
CJ Cooksey 《Biotechnic & histochemistry》2017,92(5):309-314
The history of chemical investigations into the yellow components of turmeric can be traced from 1815. Although the major yellow component of turmeric, curcumin, often is represented as a 1,3-diketone in the solid state and in nonaqueous solution, it exists in the enol form. The struggle to identify the chemical structure of curcumin continued for nearly a century and was complicated by the difficult purification of curcumin and by the presence of two additional yellow components. Food remains the main use for turmeric (old spice); its use as a dye has diminished since the 19th century, but it may have pharmaceutical uses (new spice). 相似文献
70.
Glucose oxidase electrodes were constructed on a platinum screen using polyacrylamide gel, glutaraldehyde crosslinking, and glutaraldehyde crosslinking with +0.04 volts dc on the platinum screen as the methods of enzyme immobilization. The electrodes were evaluated in an electrochemical cell for the oxidation of glucose at the enzyme electrode and the reduction of oxygen at a platinum auxiliary electrode, using constant current voltametry or under external load operation. The method of immobilization affected the extrapolated opencircuit potential as well as the half-cell potential and the steady current under external load operation. The charged glutaraldehyde electrode gave the best current performance; however, the small output (microamps) indicated that major problems in electron transfer from an enzyme catalyst to an external circuit must be resolved before such electrodes can be used in practical application. 相似文献