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41.
ABSTRACT: BACKGROUND: There is evidence to suggest that delivery of diabetes self-management support by diabetes educators in primary care may improve patient care processes and patient clinical outcomes; however, the evaluation of such a model in primary care is nonexistent in Canada. This article describes the design for the evaluation of the implementation of Mobile Diabetes Education Teams (MDETs) in primary care settings in Canada. METHODS: This study will have a non-blinded, cluster-randomized controlled trial stepped wedge design. A cluster, randomized controlled trial will be used to evaluate the Mobile Diabetes Education Teams' intervention in improving patient clinical and care process outcomes. A total of 1,200 patient charts at participating primary care sites will be reviewed for data extraction. Eligible patients will be those aged >=18, who have type 2 diabetes and a hemoglobin A1c (HbA1c) of >=8 %. Clusters (that is, primary care sites) will be randomized to the intervention and control group using a block randomization procedure within practice size as the blocking factor. A stepped wedge design will be used to sequentially roll out the intervention so that all clusters eventually receive the intervention. The time at which each cluster begins the intervention is randomized to one of the four roll out periods (0, 6, 12, and 18 months). Clusters that are randomized into the intervention later will act as the control for those receiving the intervention earlier. The primary outcome measure will be the difference in the proportion of patients who achieve the recommended HbA1c target of <=7 % between intervention and control groups. Qualitative work (in-depth interviews with primary care physicians, MDET educators and patients; and MDET educators' field notes and debriefing sessions) will be undertaken to assess the implementation process and effectiveness of the MDET intervention.Trial registrationClinicalTrials.gov NCT01553266. 相似文献
42.
Beta-galactoside alpha2,6 sialyltransferase (ST6Gal.I), the enzyme which adds sialic acid in alpha2,6-linkage on lactosaminic termini of glycoproteins, is frequently overexpressed in cancer, but its relationship with malignancy remains unclear. In this study, we have investigated the phenotypic changes induced by the expression of alpha2,6-sialylated lactosaminic chains in the human colon cancer cell line SW948 which was originally devoid of ST6Gal.I. Clones derived from transfection with the ST6Gal.I cDNA were compared with untransfected cells and mock transfectants. The ST6Gal.I-expressing clones show (1) increased adherence to fibronectin and collagen IV but not to hyaluronic acid. Treatment with Clostridium perfrigens neuraminidase reduces the binding to fibronectin and collagen IV of ST6Gal.I-expressing cells but not that of ST6Gal.I-negative cells; (2) accumulation and more focal distribution of beta1 integrins on the cell surface; (3) different distribution of actin fibers; (4) flatter morphology and reduced tendency to multilayer growth; (5) improved ability to heal a scratch wound; (6) reduced ability to grow at the subcutaneous site of injection in nude mice. Our data suggest that the presence of alpha2,6-linked sialic acid on membrane glycoconjugates increases the binding to extracellular matrix components, resulting in a membrane stabilization of beta1 integrins, further strengthening the binding. This mechanism can provide a basis for the flatter morphology and the reduced tendency to multilayer growth, resulting in a more ordered tissue organization. These data indicate that in the cell line SW948, the effect of ST6Gal.I expression is consistent with the attenuation of the neoplastic phenotype. 相似文献
43.
Audrey Lartigue Arnaud Gruez Loïc Briand Jean‐Claude Pernollet Silvia Spinelli Mariella Tegoni Christian Cambillau 《Acta Crystallographica. Section D, Structural Biology》2003,59(5):919-921
Pheromone‐binding proteins (PBPs) are small helical proteins (∼13–17 kDa) present in various sensory organs from moths and other insect species. They are involved in the transport of pheromones from the sensillar lymph to the olfactory receptors. Here, crystals of a PBP (Amel‐ASP1) originating from honeybee (Apis mellifera L.) antennae and expressed as recombinant protein using the yeast Pichia pastoris are reported. Crystals of Amel‐ASP1 have been obtained by the sitting‐drop vapour‐diffusion method using a nanodrop‐dispensing robot under the following conditions: 200 nl of 40 mg ml−1 protein solution in 10 mM Tris, 25 mM NaCl pH 8.0 was mixed with 100 nl of well solution containing 0.15 M sodium citrate, 1.5 M ammonium sulfate pH 5.5. The protein crystallizes in space group C2221, with unit‐cell parameters a = 74.8, b = 85.8, c = 50.2 Å. With one molecule in the asymmetric unit, VM is 3.05 Å3 Da−1 and the solvent content is 60%. A complete data set has been collected at 1.6 Å resolution on beamline ID14‐2 (ESRF, Grenoble). The nanodrop crystallization technique used with a novel optimization procedure made it possible to consume small amounts of protein and to obtain a unique crystal per nanodrop, suitable directly for data collection in‐house or at a synchrotron‐radiation source. 相似文献
44.
Silvestro Duprè Giuseppe Spoto Rosa Marina Matarese Mariella Orlando Doriano Cavallini 《Archives of biochemistry and biophysics》1980,202(2):361-365
After injection of various 35S- and 14C-containing compounds, the incorporation of the label into the lipoic acid present in the liver of growing rats has been determined. The best precursor for sulfur atoms, after 24 h, is cysteine; methionine and cystamine are scarcely incorporated and thiosulfate not at all. Good precursors of the carbon moiety are acetate and octanoate, whereas the incorporation of butyrate and cysteine is very low. It is concluded that lipoic acid is biosynthesized in the rat liver, and that sulfur atoms probably originate from cysteine. 相似文献
45.
Gianmauro Numico Antonella Cristofano Alessandro Mozzicafreddo Olga Elisabetta Cursio Pierfrancesco Franco Giulia Courthod Antonio Trogu Alessandra Malossi Mariella Cucchi Zuzana Sirotovà Maria Rosa Alvaro Anna Stella Fulvia Grasso Silvia Spinazzé Nicola Silvestris 《PloS one》2015,10(3)
Background
Cancer patients are frequently admitted to hospital due to acute conditions or refractory symptoms. This occurs through the emergency departments and requires medical oncologists to take an active role. The use of acute-care hospital increases in the last months of life.Patients and methods
We aimed to describe the admissions to a medical oncology inpatient service within a 16-month period with respect to patients and tumor characteristics, and the outcome of the hospital stay.Results
672 admissions of 454 patients were analysed. The majority of admissions were urgent (74.1%), and were due to uncontrolled symptoms (79.6%). Among the chief complaints, dyspnoea occurred in 15.7%, pain in 15.2%, and neurological symptoms in 14.5%. The majority of the hospitalizations resulted in discharge to home (60.6%); in 26.5% the patient died and in 11.0% was transferred to a hospice. Admissions due to symptoms correlated with a longer hospital stay and a higher incidence of in-hospital death.Conclusion
We suggest that hospital use is not necessarily a sign of inappropriately aggressive care: inpatient care is probably an unavoidable step in the cancer trajectory. Optimization of inpatient supportive procedures should be a specific task of modern medical oncology. 相似文献46.
Cleusa P. Ferri Daisy Acosta Mariella Guerra Yueqin Huang Juan J. Llibre-Rodriguez Aquiles Salas Ana Luisa Sosa Joseph D. Williams Ciro Gaona Zhaorui Liu Lisseth Noriega-Fernandez A. T. Jotheeswaran Martin J. Prince 《PLoS medicine》2012,9(2)
Background
Even in low and middle income countries most deaths occur in older adults. In Europe, the effects of better education and home ownership upon mortality seem to persist into old age, but these effects may not generalise to LMICs. Reliable data on causes and determinants of mortality are lacking.Methods and Findings
The vital status of 12,373 people aged 65 y and over was determined 3–5 y after baseline survey in sites in Latin America, India, and China. We report crude and standardised mortality rates, standardized mortality ratios comparing mortality experience with that in the United States, and estimated associations with socioeconomic factors using Cox''s proportional hazards regression. Cause-specific mortality fractions were estimated using the InterVA algorithm. Crude mortality rates varied from 27.3 to 70.0 per 1,000 person-years, a 3-fold variation persisting after standardisation for demographic and economic factors. Compared with the US, mortality was much higher in urban India and rural China, much lower in Peru, Venezuela, and urban Mexico, and similar in other sites. Mortality rates were higher among men, and increased with age. Adjusting for these effects, it was found that education, occupational attainment, assets, and pension receipt were all inversely associated with mortality, and food insecurity positively associated. Mutually adjusted, only education remained protective (pooled hazard ratio 0.93, 95% CI 0.89–0.98). Most deaths occurred at home, but, except in India, most individuals received medical attention during their final illness. Chronic diseases were the main causes of death, together with tuberculosis and liver disease, with stroke the leading cause in nearly all sites.Conclusions
Education seems to have an important latent effect on mortality into late life. However, compositional differences in socioeconomic position do not explain differences in mortality between sites. Social protection for older people, and the effectiveness of health systems in preventing and treating chronic disease, may be as important as economic and human development. Please see later in the article for the Editors'' Summary 相似文献47.
MD Barense II Groen AC Lee LK Yeung SM Brady M Gregori N Kapur TJ Bussey LM Saksida RN Henson 《Neuron》2012,75(1):157-167
Memory and perception have long been considered separate cognitive processes, and amnesia resulting from medial temporal lobe (MTL) damage is thought to reflect damage to a dedicated memory system. Recent work has questioned these views, suggesting that amnesia can result from impoverished perceptual representations in the MTL, causing an increased susceptibility to interference. Using a perceptual matching task for which fMRI implicated a specific MTL structure, the perirhinal cortex, we show that amnesics with MTL damage including the perirhinal cortex, but not those with damage limited to the hippocampus, were vulnerable to object-based perceptual interference. Importantly, when we controlled such interference, their performance recovered to normal levels. These findings challenge prevailing conceptions of amnesia, suggesting that effects of damage to specific MTL regions are better understood not in terms of damage to a dedicated declarative memory system, but in terms of impoverished representations of the stimuli those regions maintain. 相似文献
48.
Katja Conrath Alice S. Pereira Carlos E. Martins Cristina G. Timóteo Pedro Tavares Silvia Spinelli Joerg Kinne Christophe Flaudrops Christian Cambillau Serge Muyldermans Isabel Moura Jose J. G. Moura Mariella Tegoni Aline Desmyter 《Protein science : a publication of the Protein Society》2009,18(3):619-628
Nitric Oxide Reductase (NOR) is an integral membrane protein performing the reduction of NO to N2O. NOR is composed of two subunits: the large one (NorB) is a bundle of 12 transmembrane helices (TMH). It contains a b type heme and a binuclear iron site, which is believed to be the catalytic site, comprising a heme b and a non-hemic iron. The small subunit (NorC) harbors a cytochrome c and is attached to the membrane through a unique TMH. With the aim to perform structural and functional studies of NOR, we have immunized dromedaries with NOR and produced several antibody fragments of the heavy chain (VHHs, also known as nanobodies™). These fragments have been used to develop a faster NOR purification procedure, to proceed to crystallization assays and to analyze the electron transfer of electron donors. BIAcore experiments have revealed that up to three VHHs can bind concomitantly to NOR with affinities in the nanomolar range. This is the first example of the use of VHHs with an integral membrane protein. Our results indicate that VHHs are able to recognize with high affinity distinct epitopes on this class of proteins, and can be used as versatile and valuable tool for purification, functional study and crystallization of integral membrane proteins. 相似文献
49.
50.
Massimo Scandura Laura Iacolina Marco Apollonio Francesco Dessì-Fulgheri Mariella Baratti 《European Journal of Wildlife Research》2010,56(1):33-42
Four Alectoris species inhabit the Mediterranean area, where they represent important gamebirds subject to human manipulations. The Sardinian
partridge is peculiar in Europe, in that it belongs to the African species Alectoris barbara. Nevertheless, no comprehensive study has as yet investigated its genetic status as regards both the extant levels of genetic
diversity and the possible contamination due to introgressive hybridization with other Mediterranean species. For the purposes
of this study, we analyzed 65 samples of Sardinian partridges, 40 of which came from the wild population and 25 from captive
stocks. No one of them showed a mtDNA polymerase chain reaction restriction fragment length polymorphism haplotype assigned
to another species than A. barbara, thus, ruling out a possible introgression in the maternal line. In addition, we compared these samples with 94 partridges
from other circum-Mediterranean populations using a set of eight chicken (Gallus gallus) microsatellites. A low level of genetic variation was observed in the Sardinian population (H
E = 0.310; k
AR = 2.69), comparable only to that observed in the Sicilian rock partridge (A. graeca). The comparison with the Tunisian population showed that its present genetic composition is consistent with a historical
introduction from North Africa, showing possible effects of a post-introductional genetic drift. Bayesian tests assigned all
but one individuals with >90% probability to A. barbara, thus, providing evidence that no or only a few exotic Alectoris genes have introgressed into Sardinian partridges. 相似文献