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11.
AIM: To validate tissue microarray (TMA) for endometrial cancer by comparing immunohistochemical staining results of triplicate core biopsies on TMA with the results of full-section analysis. METHODS: The study material consisted of slides and selected tissue blocks of 41 patients with endometrioid cancer of the endometrium. A TMA was constructed. Both the TMA and the slides were stained with the same antibodies against progesterone receptor (PR), oestrogen receptor, p53 and epithelial membrane antigen (EMA). Concordance between results was expressed as the kappa statistic. RESULTS: Concordance between the staining results of TMA and whole slides was good for PR (kappa = 0.69), oestrogen receptor (kappa = 0.78), p53 (kappa = 0.81) and EMA (kappa = 0.72). Concordance between the results on TMA and slides depends on the number of assessable cores per tumour. Three assessable cores per case result in outcomes that are at least 94% similar to those achieved using conventional tissue sections with a two-class scoring system. This is independent of focal or diffuse staining patterns. CONCLUSION: TMA is a useful tool for further analysis of the molecular pathways in endometrial cancer. The effect of selection has to be taken into account when the prognostic value of protein expression on TMA is determined. 相似文献
12.
Attachment of infectious influenza A viruses of various subtypes to live mammalian and avian cells as measured by flow cytometry 总被引:3,自引:0,他引:3
Rimmelzwaan GF Nieuwkoop NJ de Mutsert G Boon AC Kuiken T Fouchier RA Osterhaus AD 《Virus research》2007,129(2):175-181
At present there is much interest in the cell tropism and host range of influenza viruses, especially those of the H5N1 subtype. We wished to develop a method that would enable investigation of attachment of infectious virus through the interaction of the hemagglutinin molecule and live mammalian and avian cells and the subsequent infection of these cells. To this end, influenza viruses of various HA subtypes were constructed that either carry the green fluorescent protein (GFP) instead of the neuraminidase protein, or that express GFP in the cytoplasm of infected cells. The HA genes were derived from influenza viruses A/PR/8/34 (H1N1), A/Netherlands/178/95 (H3N2) and A/Vietnam/1194/04 (H5N1). Using these pairs of viruses, attachment and post-attachment events in the virus replication cycle can be distinguished. In general, the expression of NeuAc(alpha2-3)Gal or NeuAc(alpha2-6)Gal receptors on the cells tested corresponded with the attachment of the viruses that were studied with respect to predicted receptor specificity. Virus attachment was not always predictive for efficient infection of the cells. 相似文献
13.
Berkhoff EG Geelhoed-Mieras MM Jonges M Smith DJ Fouchier RA Osterhaus AD Rimmelzwaan GF 《Virus research》2007,126(1-2):282-287
Influenza virus-specific CD4+ T-helper cells were cloned that recognized a virus strain isolated in 1981, but that failed to recognize more recent strains. The HLA-DR*1601-restricted epitope recognized was located in the hemagglutinin (HA(99-113)) and the naturally occurring A-->V substitution at position 106 was responsible for abrogating the recognition by HA(99-113)-specific CD4+ T-cells. This amino acid substitution was found in influenza A/H3N2 viruses that circulated between 1999 and 2005 and did not affect recognition by virus-specific antibodies. It was speculated that influenza viruses could evade recognition by virus-specific CD4+ T-cells, at least temporarily. 相似文献
14.
Fleur Berenschot Marcel A. G. van Aken Christel Hessels Bram Orobio de Castro Ysbrand Pijl Barbara Montagne Guus van Voorst 《European child & adolescent psychiatry》2014,23(7):563-570
It has been argued that a heightened emotional sensitivity interferes with the cognitive processing of facial emotion recognition and may explain the intensified emotional reactions to external emotional stimuli of adults with personality pathology, such as borderline personality disorder (BPD). This study examines if and how deviations in facial emotion recognition also occur in adolescents with personality pathology. Forty-two adolescents with personality pathology, 111 healthy adolescents and 28 psychiatric adolescents without personality pathology completed the Emotion Recognition Task, measuring their accuracy and sensitivity in recognizing positive and negative emotion expressions presented in several, morphed, expression intensities. Adolescents with personality pathology showed an enhanced recognition accuracy of facial emotion expressions compared to healthy adolescents and clients with various Axis-I psychiatric diagnoses. They were also more sensitive to less intensive expressions of emotions than clients with various Axis-I psychiatric diagnoses, but not more than healthy adolescents. As has been shown in research on adults with BPD, adolescents with personality pathology show enhanced facial emotion recognition. 相似文献
15.
Catharina Carolina de Jong Wynand JG Ros Guus Schrijvers 《Journal of medical Internet research》2014,16(1)
Background
In support of professional practice, asynchronous communication between the patient and the provider is implemented separately or in combination with Internet-based self-management interventions. This interaction occurs primarily through electronic messaging or discussion boards. There is little evidence as to whether it is a useful tool for chronically ill patients to support their self-management and increase the effectiveness of interventions.Objective
The aim of our study was to review the use and usability of patient-provider asynchronous communication for chronically ill patients and the effects of such communication on health behavior, health outcomes, and patient satisfaction.Methods
A literature search was performed using PubMed and Embase. The quality of the articles was appraised according to the National Institute for Health and Clinical Excellence (NICE) criteria. The use and usability of the asynchronous communication was analyzed by examining the frequency of use and the number of users of the interventions with asynchronous communication, as well as of separate electronic messaging. The effectiveness of asynchronous communication was analyzed by examining effects on health behavior, health outcomes, and patient satisfaction.Results
Patients’ knowledge concerning their chronic condition increased and they seemed to appreciate being able to communicate asynchronously with their providers. They not only had specific questions but also wanted to communicate about feeling ill. A decrease in visits to the physician was shown in two studies (P=.07, P=.07). Increases in self-management/self-efficacy for patients with back pain, dyspnea, and heart failure were found. Positive health outcomes were shown in 12 studies, where the clinical outcomes for diabetic patients (HbA1c level) and for asthmatic patients (forced expiratory volume [FEV]) improved. Physical symptoms improved in five studies. Five studies generated a variety of positive psychosocial outcomes.Conclusions
The effect of asynchronous communication is not shown unequivocally in these studies. Patients seem to be interested in using email. Patients are willing to participate and are taking the initiative to discuss health issues with their providers. Additional testing of the effects of asynchronous communication on self-management in chronically ill patients is needed. 相似文献16.
17.
18.
van der Stelt M van Kuik JA Bari M van Zadelhoff G Leeflang BR Veldink GA Finazzi-Agrò A Vliegenthart JF Maccarrone M 《Journal of medicinal chemistry》2002,45(17):3709-3720
This study was aimed at finding structural requirements for the interaction of the acyl chain of endocannabinoids with cannabinoid receptors, membrane transporter protein, and fatty acid amide hydrolase (FAAH). To this end, the flexibility of the acyl chain was restricted by introduction of an 1-hydroxy-2Z,4E-pentadiene system in anandamide (N-arachidonoylethanolamine, AEA) and 2-arachidonoylglycerol (2-AG) at various positions using different lipoxygenases. This brought about selectivity and attenuated the binding potency of AEA and 2-AG. Although the displacement constants were modest, 15(S)-hydroxy-eicosa-5Z,8Z,11Z,13E-tetraenoyl-N-(2-hydroxyethyl)amine was found to bind selectively to the CB(1) receptor, whereas its 1-arachidonoyl-sn-glycerol analogue and 13(S)-hydroxy-octadeca-9Z,11E-dienoyl-N-(2-hydroxyethyl)amine could selectively bind to the CB(2) receptor. 11(S)-Hydroxy-eicosa-5Z,8Z,12E,14Z-tetraenoyl-N-(2-hydroxyethyl)amine did not bind to either receptor, whereas 12(S)-hydroxy-eicosa-5Z,8Z,10E,14Z-tetraenoyl-N-(2-hydroxyethyl)amine did bind to both CB receptors with an affinity similar to that of AEA. All oxygenated anandamide derivatives were good inhibitors of FAAH (low micromolar K(i)) but were ineffective on the AEA transporter. 2-AG rapidly isomerizes into 1(3)-arachidonoyl-sn-glycerol. Both 1- and 3-arachidonoyl-sn-glycerol did not bind to either CB receptor and did not interfere with AEA transport. Thus, after it is isomerized, 2-AG is inactivated, thereby decreasing effective concentrations of 2-AG. Analysis of (1)H NMR spectra revealed that chloroform did not induce notably different conformations in the acyl chain of 15(S)-hydroxy-eicosa-5Z,8Z,11Z,13E-tetraenoic acid as compared with water. Molecular dynamics (MD) simulations of AEA and its analogues in the presence of explicit water molecules revealed that a tightly folded conformation of the acyl chain is not the only requirement for CB(1) binding. Structural details of the C(2)-C(15) loop, such as an sp(2) carbon at position 11, are necessary for receptor binding. The MD simulations may suggest that the average orientations of the pentyl tail of AEA and 12(S)-hydroxy-eicosa-5Z,8Z,10E,14Z-tetraenoyl-N-(2-hydroxyethyl)amine are different from that of the low-affinity, inactive ligands. 相似文献
19.
Ntanios FY Duchateau GS 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》2002,72(1):32-39
Blood cholesterol levels are affected by diet and in particular by the type and amount of fat intake. In recent years, vegetable oil spreads containing plant sterols/stanols (as their fatty acid esters) have been developed. Numerous clinical trials on spreads with added plant sterols/stanols have shown that they have much greater cholesterol-lowering properties than conventional vegetable oil spreads. Plant sterols decrease both dietary and biliary cholesterol absorption in the small intestine, with a consequential increase in excretion of cholesterol. It is also recognized that plant sterol/stanol-enriched, cholesterol-lowering spreads, if consumed regularly, may induce a 10-20% decrease in plasma carotenoids, adjusted for changes in plasma lipids. A 10-20% decrease in plasma carotenoids falls well within the seasonal variation observed in individuals. Our current understanding of the physiological functions of carotenoids does not indicate any health risk associated with the slight decrease in their blood levels due to the intake of plant sterol/stanol. The questions that have been raised, though, are how plant sterols/stanols affect plasma carotenoid levels, and in addition, what quantity of fruits and vegetables (the richest dietary sources of carotenoids) would have to be consumed to improve plasma carotenoid levels? The current mini-review covers the cholesterol-lowering effect of plant sterols, their mechanisms of action and effect on blood carotenoids, and concludes with the potential heath benefits of daily intake of plant sterol-enriched spreads. 相似文献
20.
Leslie A. Reperant Geert van Amerongen Marco W.G. van de Bildt Guus F. Rimmelzwaan Andrew P. Dobson Albert D.M.E. Osterhaus Thijs Kuiken 《Emerging infectious diseases》2008,14(12):1835-1841
Eating infected wild birds may put wild carnivores at high risk for infection with highly pathogenic avian influenza (HPAI) virus (H5N1). To determine whether red foxes (Vulpes vulpes) are susceptible to infection with HPAI virus (H5N1), we infected 3 foxes intratracheally. They excreted virus pharyngeally for 3–7 days at peak titers of 103.5–105.2 median tissue culture infective dose (TCID50) per mL and had severe pneumonia, myocarditis, and encephalitis. To determine whether foxes can become infected by the presumed natural route, we fed infected bird carcasses to 3 other red foxes. These foxes excreted virus pharyngeally for 3–5 days at peak titers of 104.2–104.5 TCID50/mL, but only mild or no pneumonia developed. This study demonstrates that red foxes fed bird carcasses infected with HPAI virus (H5N1) can excrete virus while remaining free of severe disease, thereby potentially playing a role in virus dispersal. 相似文献