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51.
Ian M Mackay Tim Gardam Katherine E Arden Suzi McHardy David M Whiley Erin Crisante Theo P Sloots 《Journal of clinical virology》2003,28(3):291-302
BACKGROUND: Herpesviruses are a significant cause of human morbidity. Traditional approaches to the identification of these viruses require infectious or at least antigenic virus. Multiplex PCR (mPCR) is capable of simultaneously amplifying a range of targets from a single preparation of nucleic acids and when combined with a suitable detection assay, it is capable of discriminating each of the amplicons. OBJECTIVES: Several methods have been described in the literature, however, they lack one or more significant design features required to suitably control a routinely applied nucleic acid amplification assay. We aimed to design a multiplex herpesvirus PCR that could co-amplify eight human herpesvirus targets plus an internal control (IC) molecule in a single tube. STUDY DESIGN: Primers were designed to target the DNA polymerase genes of each of the human herpesviruses. Synthetic controls were developed to act as templates for the evaluation of assay sensitivity and specificity and for development of an in-house competitive quantitative PCR. Amplicon was discriminated using a simplified enzyme linked amplicon hybridisation assay (ELAHA). RESULTS AND CONCLUSIONS: For routine diagnostic use we reduced the number of herpesviral targets from 8 to 6 in order to maintain adequate clinical sensitivity. The ELAHA proved more sensitive than agarose gel electrophoresis. Additionally, 36 cytomegalovirus positive patients were examined with an in-house quantitative PCR-ELAHA which was developed to confirm that that the mPCR's co-detection limit of 10(2) copy of synthetic template per millilitre was relevant for use in detecting virus from clinical samples. The mPCR-ELAHA was then applied to the screening of 174 patient specimens resulting in a specificity of 98% and a sensitivity of 93%. This preliminary study demonstrated that the mPCR-ELAHA was a complete approach to the detection of herpesviruses from a range of clinical samples and disease states. 相似文献
52.
53.
Autocrine motility factor (AMF) is one of the motility cytokines regulating tumor cell migration, therefore identification
of the signaling pathway coupled with it has critical importance. Previous studies revealed several elements of this pathway
predominated by lipoxygenase-PKC activations but the role for tyrosine kinases remained questionable. Motility cytokines frequently
have mitogenic effect as well, producing activation of overlapping signaling pathways therefore we have used B16a melanoma
cells as models where AMF has exclusive motility effect. Our studies revealed that in B16a cells AMF initiated rapid (1–5
min) activation of the protein tyrosine kinase (PTK) cascade inducing phosphorylation of 179, 125, 95 and 40/37 kD proteins
which was mediated by upstream cyclo- and lipoxygenases. The phosphorylated proteins were localized to the cortical actin-stress
fiber attachment zones in situ by confocal microscopy. On the other hand, AMF receptor activation induced significant decrease
in overall serine-phosphorylation level of cellular proteins accompanied by serine phosphorylation of 200, 90, 78 and 65 kd
proteins. The decrease in serine phosphorylation was independent of PTKs, PKC as well as cyclo- and lipoxygenases. However,
AMF induced robust translocation of PKCα to the stress fibers and cortical actin suggesting a critical role for this kinase
in the generation of the motility signal. Based on the significant decrease in serine phosphorylation after AMF stimulus in
B16a cells we postulated the involvement of putative serine/threonine phosphatase(s) upstream lipoxygenase and activation
of the protein tyrosine kinase cascade downstream cyclo- and lipoxygenase(s) in the previously identified autocrine motility
signal.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
54.
Rademakers R Melquist S Cruts M Theuns J Del-Favero J Poorkaj P Baker M Sleegers K Crook R De Pooter T Bel Kacem S Adamson J Van den Bossche D Van den Broeck M Gass J Corsmit E De Rijk P Thomas N Engelborghs S Heckman M Litvan I Crook J De Deyn PP Dickson D Schellenberg GD Van Broeckhoven C Hutton ML 《Human molecular genetics》2005,14(21):3281-3292
55.
Tim Martin Mark A McDaniel Melissa J Guynn Jon M Houck C Chad Woodruff Joel Pearson Bish Sandra N Moses Dubravko Kici? Claudia D Tesche 《International journal of psychophysiology》2007,64(3):247-258
We measured brain activity using magnetoencephalography in five participants during ongoing tasks that included prospective memory, retrospective memory, and oddball trials. Sources were identified in the hippocampal formation and posterior parietal and frontal lobes. Posterior parietal cortex activation had an earlier onset in the prospective memory condition than retrospective memory or oddball conditions, a higher level of theta activity in the retrospective condition, and higher levels of upper alpha in the prospective and oddball conditions. Activation of the hippocampal formation had a longer duration in the retrospective memory and prospective memory conditions than the oddball condition, but prominent alpha and theta band activity was present in all three conditions. We interpret the early (87 ms) onset of activity in parietal cortex as evidence for an initial noticing of appropriate conditions for a PM response. Hippocampal activity may reflect a subsequent memory search for the intended action. 相似文献
56.
Vincenzo Cerundolo Adrian Kelly Tim Elliott John Trowsdale Alain Townsend 《European journal of immunology》1995,25(2):554-562
The B cell line 721.174 has lost the ability to present intracellular antigens to major histocompatibility complex (MHC) class I-restricted cytotoxic T lymphocytes (CTL). This phenotype results from a homozygous deletion in the MHC that includes the peptide transporter genes TAP1 and TAP2, and the proteasome subunits LMP2 and LMP7. Recent work has shown that such cells transfected with TAP genes load their class I molecules with endogenous peptides, and present several viral epitopes to class I-restricted CTL. These data implied that the LMP2 and LMP7 genes were not required for the presentation of most epitopes through class I molecules. By contrast, while confirming the previous reports, we have identified several epitopes that appear to require genes in the MHC in addition to the TAP for their presentation. Further analysis localizes the defect to proteolysis in the cytosol. In one case, presentation could be partially restored by re-expression of full-length LMP7. Control experiments with LMP7, from which the putative pro-region had been removed, failed to restore presentation, and this lack of effect correlated with failure of the shortened LMP7 to incorporate into the proteasome. These results suggest a role for LMP7 in the generation of a viral epitope, but leave open the possibility that additional genes within the .174 deletion are required for full restoration of antigen presentation. 相似文献
57.
58.
Tim A Holt David Stables Julia Hippisley-Cox Shaun O'Hanlon Azeem Majeed 《The British journal of general practice》2008,58(548):192-196
BACKGROUND: Around 1% of the UK population has diabetes that is either undiagnosed or unrecorded on practice disease registers. AIM: To estimate the number of people in UK primary care databases with biochemical evidence of undiagnosed diabetes. To develop simple practice-based search techniques to support early recognition of diabetes. DESIGN OF STUDY: Cross-sectional survey of 3 630 296 electronic records. SETTING: Four hundred and eighty UK practices contributing to the QRESEARCH database. METHOD: Electronic searches to identify people with no diabetes diagnosis in one of two categories (A and B), using the most recently recorded blood glucose measurement: random blood glucose level >or=11.1 mmol/l or fasting blood glucose level >or=7.0 mmol/l (A); either a random or a fasting blood glucose level >or=7.0 mmol/l (B). An additional outcome measure was the proportion of the population with at least one blood glucose measurement in the record. RESULTS: The number (percentage) identified in category A was 3758 (0.10% of the total population); the number in category B was 32 785 (0.90%). Projected to a practice of 7000 patients, around eight patients have biochemical evidence of undiagnosed diabetes, and 68 have results suggesting the need for further follow-up. One-third of people aged over 40 years without diabetes have a blood glucose measurement in the past 2 years in their record. CONCLUSION: People with possible undiagnosed diabetes are readily identifiable in UK primary care databases through electronic searches using blood glucose data. People with borderline levels, who may benefit from interventions to reduce their risk of progression to diabetes, can also be identified using practice-based software. 相似文献
59.
Three British physicians briefly review the final programs in a BBC series, "Doctors' Dilemmas," each consisting of a case history followed by a discussion involving health professionals, administrators, and lawyers. Taylor, an occupational physician, comments on the episode in which a company doctor is asked by management to disclose confidential information about an employee. Psychiatrist Jerram discusses his reactions to the program presenting the dilemmas of treating a patient with anorexia nervosa against her will. Forsythe, a community physician, reviews the final episode, which dealt with resource allocation, the role of health professionals within the National Health Service, and the potential conflict between the NHS and private practice. 相似文献
60.
Fürstenau Daniel Haneke Hannah Spies Claudia Walz Tim Schewina Kai Höft Moritz Mörgeli Rudolf Balzer Felix 《Zeitschrift fur Gesundheitswissenschaften》2022,30(1):99-110
Journal of Public Health - The purpose of this paper is to investigate the implementation of value-based care principles in the context of frailty in the perioperative process, highlighting the... 相似文献