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31.
Nurses account for approximately 50 % of total hospital budgets and their allocation to medical units and shifts can significantly affect the quality of care provided to patients. The adoption of flexible shift schedules and the assessment of actual nursing time can enable sensible resource planning, balancing the quality of care with efficiency in resource use. Starting from the concept that nurse requirements are triggered by patient needs, which are stochastic in nature both for clinical activities and their duration, this paper proposes an innovative Nurse Requirement Planning model grounded on the concept of the clinical pathway (the “standard” sequence of diagnostic, therapeutic and care activities a patient with certain pathology should undertake over time) with its inner routing probability and patient dependence on nurses, which can be correlated to the time needed to perform nursing tasks. In merging and modelling these two aspects, the method summarizes the best features of acuity-quality and timed-task/activity techniques, well known although not usually applied for reasons of demands on clinicians’ time. Instead, in this paper, for each shift of the day, hospital management is enabled to choose the optimal number of nurses to meet actual requirements according to a desired service level and personnel saturation by means of a tool that simulates the patient flow in a medical unit based on automatic data retrieval from hospital databases. The validation and verification of the proposal were undertaken in a stroke unit. 相似文献
32.
Deiana M Incani A Rosa A Atzeri A Loru D Cabboi B Paola Melis M Lucas R Morales JC Assunta Dessì M 《Chemico-biological interactions》2011,(3):232-239
Hydroxytyrosol (2-(3′,4′-dihydroxyphenyl)ethanol; HT), the most active ortho-diphenolic compound, present either in free or esterified form in extravirgin olive oil, is extensively metabolized in vivo mainly to O-methylated, O-sulfated and glucuronide metabolites. We investigated the capacity of three glucuronide metabolites of HT, 3′-O-β-d-glucuronide and 4′-O-β-d-glucuronide derivatives and 2-(3′,4′-dihydroxyphenyl)ethanol-1-O-β-d-glucuronide, in comparison with the parent compound, to inhibit H2O2 induced oxidative damage and cell death in LLC-PK1 cells, a porcine kidney epithelial cell line. H2O2 treatment exerted a toxic effect inducing cell death, interacting selectively within the pro-death extracellular-signal relate kinase (ERK 1/2) and the pro-survival Akt/PKB signaling pathways. It also produced direct oxidative damage initiating the membrane lipid peroxidation process. None of the tested glucuronides exhibited any protection against the loss in renal cell viability. They also failed to prevent the changes in the phosphorylation states of ERK and Akt, probably reflecting their inability to enter the cells, while HT was highly effective. Notably, pretreatment with glucuronides exerted a protective effect at the highest concentration tested against membrane oxidative damage, comparable to that of HT: the formation of malondialdehyde, fatty acid hydroperoxides and 7-ketocholesterol was significantly inhibited. 相似文献
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Scala E Alessandri C Palazzo P Pomponi D Liso M Bernardi ML Ferrara R Zennaro D Santoro M Rasi C Mari A 《PloS one》2011,6(9):e24912
Background
IgE recognition of panallergens having highly conserved sequence regions, structure, and function and shared by inhalant and food allergen sources is often observed.Methods
We evaluated the IgE recognition profile of profilins (Bet v 2, Cyn d 12, Hel a 2, Hev b 8, Mer a 1, Ole e 2, Par j 3, Phl p 12, Pho d 2), PR-10 proteins (Aln g 1, Api g 1, Bet v 1.0101, Bet v 1.0401, Cor a 1, Dau c 1 and Mal d 1.0108) and tropomyosins (Ani s 3, Der p 10, Hel as 1, Pen i 1, Pen m 1, Per a 7) using the Immuno-Solid phase Allergen Chip (ISAC) microarray system. The three panallergen groups were well represented among the allergenic molecules immobilized on the ISAC. Moreover, they are distributed in several taxonomical allergenic sources, either close or distant, and have a route of exposure being either inhalation or ingestion.Results
3,113 individuals (49.9% female) were selected on the basis of their reactivity to profilins, PR-10 or tropomyosins. 1,521 (48.8%) patients were reactive to profilins (77.6% Mer a 1 IgE+), 1,420 (45.6%) to PR-10 (92.5% Bet v 1 IgE+) and 632 (20.3%) to tropomyosins (68% Der p 10 IgE+). A significant direct relationship between different representative molecules within each group of panallergens was found. 2,688 patients (86.4%) recognized only one out of the three distinct groups of molecules as confirmed also by hierarchical clustering analysis.Conclusions
Unless exposed to most of the allergens in the same or related allergenic sources, a preferential IgE response to distinct panallergens has been recorded. Allergen microarray IgE testing increases our knowledge of the IgE immune response and related epidemiological features within and between homologous molecules better describing the patients'' immunological phenotypes. 相似文献35.
Differential toxicity of TAR DNA‐binding protein 43 isoforms depends on their submitochondrial localization in neuronal cells 下载免费PDF全文
Illari Salvatori Alberto Ferri Silvia Scaricamazza Ilaria Giovannelli Alessia Serrano Simona Rossi Nadia D'Ambrosi Mauro Cozzolino Andrea Di Giulio Sandra Moreno Cristiana Valle Maria Teresa Carrì 《Journal of neurochemistry》2018,146(5):585-597
36.
Daniela Cocchi Angela Santagostino Irit Gil-Ad Sergio Ferri Eugenio E. Müller 《Life sciences》1977,20(12):2041-2046
The effect of Leu5-enkephalin on growth hormone (GH) and prolactin (PRL) release was studied in the infant rat and compared to that of morphine. In 10 day-old pups, intracerebroventricular injection of Leu5-enkephalin (50, 75 and 100 μg) resulted in a dose-related increase in plasma GH; morphine was active as GH releaser at the dose of 5 and 10 μg, but not at 2.5 μg. Pretreatment with naloxone (2 mg/kg ip) suppressed the GH-releasing effect of either Leu5-enkephalin (100 μg) or morphine (10 μg). Leu5-enkephalin (75 and 100 μg) induced a rise in plasma PRL which was neither dose-related nor antagonized by naloxone; morphine (5 and 10 μg) was active as PRL releaser and its effect was antagonized by naloxone. These results indicate that: 1) Leu5-enkephalin stimulates both GH and PRL release; 2) the release of GH by Leu5-enkephalin but likely not that of PRL involves specific opiate receptors; 3) morphine releases GH and PRL through specific opiate receptors. 相似文献
37.
Jennifer N. Murdoch Christine Damrau Anju Paudyal Debora Bogani Sara Wells Nicholas D. E. Greene Philip Stanier Andrew J. Copp 《Disease models & mechanisms》2014,7(10):1153-1163
Neural tube defects (NTDs) are among the commonest and most severe forms of developmental defect, characterized by disruption of the early embryonic events of central nervous system formation. NTDs have long been known to exhibit a strong genetic dependence, yet the identity of the genetic determinants remains largely undiscovered. Initiation of neural tube closure is disrupted in mice homozygous for mutations in planar cell polarity (PCP) pathway genes, providing a strong link between NTDs and PCP signaling. Recently, missense gene variants have been identified in PCP genes in humans with NTDs, although the range of phenotypes is greater than in the mouse mutants. In addition, the sequence variants detected in affected humans are heterozygous, and can often be detected in unaffected individuals. It has been suggested that interactions between multiple heterozygous gene mutations cause the NTDs in humans. To determine the phenotypes produced in double heterozygotes, we bred mice with all three pairwise combinations of Vangl2Lp, ScribCrc and Celsr1Crsh mutations, the most intensively studied PCP mutants. The majority of double-mutant embryos had open NTDs, with the range of phenotypes including anencephaly and spina bifida, therefore reflecting the defects observed in humans. Strikingly, even on a uniform genetic background, variability in the penetrance and severity of the mutant phenotypes was observed between the different double-heterozygote combinations. Phenotypically, Celsr1Crsh;Vangl2Lp;ScribCrc triply heterozygous mutants were no more severe than doubly heterozygous or singly homozygous mutants. We propose that some of the variation between double-mutant phenotypes could be attributed to the nature of the protein disruption in each allele: whereas ScribCrc is a null mutant and produces no Scrib protein, Celsr1Crsh and Vangl2Lp homozygotes both express mutant proteins, consistent with dominant effects. The variable outcomes of these genetic interactions are of direct relevance to human patients and emphasize the importance of performing comprehensive genetic screens in humans.KEY WORDS: Neural tube defects, Planar cell polarity, Genetic interactions, Craniorachischisis, Multiple heterozygosity 相似文献
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39.
Mechano-chemical energy transduction in biological systems. The effect of mechanical stimulation on the polymerization of actin: a kinetic study. 下载免费PDF全文
Mechanical stimulation (forced circulation in narrow tubing) accelerates as much as 10-fold the rate of polymerization of actin. The increase in the rate is proportional to the intensity of the stimulation for flow rates between 0 and 3 cm/s. This supports the hypothesis that a statistical factor (the orientation of the flowing particles) is influenced by the flow. Comparison of the kinetics of the polymerization of resting and of mechanically stimulated actin solutions shows that both the nucleation and the elongation steps are accelerated. It is thus concluded that flow orients not only the oligomeric structures but also the actin monomers. The elongation reaction, also in the flow-stimulated samples, occurs always by the addition of ATP--G-actin (or ATP-containing oligomers) and not by the fusion of ADP-containing oligomeric structures. 相似文献
40.
G Ferrières S Villard M Pugnière J C Mani I Navarro-Teulon F Rharbaoui D Laune E Loret B Pau C Granier 《European journal of biochemistry》2000,267(6):1819-1829
Randomized peptide sequences displayed at the surface of filamentous phages are often used to select antibody ligands. The selected sequences are generally further used in the form of synthetic peptides; however, as such, their affinity for the selecting antibody is extremely variable and factors influencing this affinity have not been fully deciphered. We have used an f88.4 phage-displayed peptide library to identify ligands of mAb 11E12, an antibody reactive to human cardiac troponin I. A majority of the sequences thus selected showed a (T/A/I/L) EP(K/R/H) motif, homologous to the Y-TEPH motif identified by multiple peptide synthesis as the critical motif recognized by mAb 11E12 in the peptide epitope. A set of 15-mer synthetic peptides derived from the phage-selected sequences was used in BIACORE to characterize their interaction with mAb 11E12. Most peptides exhibited affinities in the 7-26 nM range. These affinities represented, however, only 1.9-7. 5% of the affinity of the 15-mer peptide epitope. In circular dichroism experiments, the peptide epitope showed a propensity to have some stabilized conformation, whereas a low-affinity peptide selected by phage-display did not. To try to decipher the molecular basis of this difference in affinity, new peptides were prepared by grafting the N- or the C-terminal sequence of the peptide epitope to the Y-TEPK motif of a low-affinity peptide selected by phage-display. These hybrid peptides showed marked increases both in affinity (as assessed using BIACORE) and in inhibitory potency (as assessed in competition ELISA), compared with the parent sequence. Thus, the sequences flanking the motif, although not containing critical residues, convey some determinants necessary for high affinity. The affinity of a given peptide strongly depends on its capacity to maintain the antigenically reactive structure it has on the phage, implying that it is impossible to predict whether high- or low-affinity peptides will be obtained from phage display. 相似文献