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Susan C. Fox Jane A. May Natalia Dovlatova Jackie R. Glenn Andrew Johnson Ann E. White 《Platelets》2019,30(3):290-295
Measurement of P-selectin on activated platelets as a means of measuring platelet function utilizing the technology described here has the advantage of not requiring immediate access to specialist equipment and expertise. Blood samples are activated, fixed, stored, and transported to a central laboratory for flow cytometric analysis. Here we have compared P-selectin with other more traditional approaches to measuring platelet function in blood and/or platelet-rich plasma (PRP) from patients with acute coronary syndromes on treatment for at least 1 month with either aspirin and clopidogrel or aspirin with prasugrel. The comparators were light transmission aggregometry (LTA), VerifyNow and Multiplate aggregometry (for determining the effects of aspirin) and LTA, VerifyNow and Multiplate together with the BioCytex VASP phosphorylation assay (for the P2Y12 antagonists). The P-selectin Aspirin Test revealed substantial inhibition of platelet function in all but three of 96 patients receiving aspirin with clopidogrel and in none of 51 patients receiving aspirin and prasugrel. The results were very similar to those obtained using LTA. There was only one patient with high residual platelet aggregation and low P-selectin expression. The same patients identified as “non-responders” to aspirin also presented with the highest residual platelet activity as measured using the VerifyNow system, although not quite as well separated from the other values. With the Multiplate test only one of these patients clearly stood out from the others. The results obtained using the P-selectin P2Y12 Test in 102 patients taking aspirin and clopidogrel were similar to the more traditional approaches in that a wide scatter of results was obtained. Generally, high values seen with the P-selectin P2Y12 Test were also high with the LTA, VerifyNow, Multiplate, and BioCytex VASP P2Y12 Tests. Similarly, low residual platelet function using the P2Y12 test was seen irrespective of the testing procedure used. However, there were differences in some patients. Prasugrel was always more effective than clopidogrel in inhibiting platelet function with none of 56 patients (P-selectin and VerifyNow), only 2 of 56 patients (Multiplate) and only 3 of 56 patients (Biocytex VASP) demonstrating high on-treatment residual platelet reactivity (HRPR) defined using previously published cut-off values. The exception was LTA where there were 11 of 56 patients with HRPR. It remains to be seen which experimental approach provides the most useful information regarding outcomes after adjusting therapies in treated patients. 相似文献
3.
Episodic memory is defined as the ability to recall events in a spatiotemporal context. Formation of such memories is critically dependent on the hippocampal formation and its inputs from the entorhinal cortex. To be able to support the formation of episodic memories, entorhinal cortex and hippocampal formation should contain a neuronal code that follows several requirements. First, the code should include information about position of the agent (“where”), sequence of events (“when”), and the content of the experience itself (“what”). Second, the code should arise instantly thereby being able to support memory formation of one‐shot experiences. For successful encoding and to avoid interference between memories during recall, variations in location, time, or in content of experience should result in unique ensemble activity. Finally, the code should capture several different resolutions of experience so that the necessary details relevant for future memory‐based predictions will be stored. We review how neuronal codes in entorhinal cortex and hippocampus follow these requirements and argue that during formation of episodic memories entorhinal cortex provides hippocampus with instant information about ongoing experience. Such information originates from (a) spatially modulated neurons in medial entorhinal cortex, including grid cells, which provide a stable and universal positional metric of the environment; (b) a continuously varying signal in lateral entorhinal cortex providing a code for the temporal progression of events; and (c) entorhinal neurons coding the content of experiences exemplified by object‐coding and odor‐selective neurons. During formation of episodic memories, information from these systems are thought to be encoded as unique sequential ensemble activity in hippocampus, thereby encoding associations between the content of an event and its spatial and temporal contexts. Upon exposure to parts of the encoded stimuli, activity in these ensembles can be reinstated, leading to reactivation of the encoded activity pattern and memory recollection. 相似文献
4.
C. Jacquet F. Goehringer E. Baux J.A. Conrad M.O. Ganne Devonec J.L. Schmutz G. Mathey H. Tronel T. Moulinet I. Chary-Valckenaere T. May C. Rabaud 《Médecine et maladies infectieuses》2019,49(2):112-120
Objective
The teaching hospital of Nancy, France, implemented a specific multidisciplinary care pathway (French acronym AMDPL) to improve the management of patients presenting with Lyme borreliosis (LB) suspicion. We aimed to assess the first year of activity of this care pathway.Patients and methods
We included all patients managed in the AMDPL pathway from November 1, 2016 to October 31, 2017. The first step was a dedicated Lyme disease consultation with an infectious disease specialist. Following this consultation, the LB diagnosis was either confirmed and adequate treatment was prescribed, or a differential diagnosis was established and patients received adequate management, or further investigations were required and patients were offered multidisciplinary management as part of a day hospitalization.Results
A total of 468 patients were included. LB diagnosis was confirmed in 15% of patients (69/468), 49% of patients received a differential diagnosis, and 26% (122/468) of patients had the LB diagnosis ruled out without receiving any other diagnosis.Conclusions
This is to our knowledge the first multidisciplinary center implemented in France for the management of patients presenting with LB suspicion related to polymorphous signs and symptoms. Several diagnoses could be confirmed or corrected, although some symptoms and complaints could not be explained. This cohort could improve our knowledge of LB and its differential diagnoses. 相似文献5.
6.
Daniel Poremski Mark Alexander Tina Fang Giles Ming‐Yee Tan Samantha Ong Alex Su Daniel Fung Hong Choon Chua 《Asia-Pacific psychiatry》2020,12(1)
People with mental illness may be unable to provide critical input about the care they wish to receive during a psychiatric crisis because of altered mental states. It is therefore imperative that clinicians seek to understand service users' wishes for care while they are well and able to provide meaningful input into the discussion. Achieving such an end may be done by discussing and completing a psychiatric advance directive. However, very few Asian countries have legislation that supports such advance directives. The present article seeks to give physicians more information about advance psychiatric directives and the potential role they could play to improve the healthcare provided in Asia to people at risk of losing capacity due to a mental illness. The degree to which mental health legislation supports psychiatric advance directives is documented for each country of South East Asia and Eastern Asia. 相似文献
7.
Facundo Davaro Jacob Roberts Allison May Coleman McFerrin Sameer Siddiqui Zachary Hamilton 《Journal of robotic surgery》2020,14(3):447-454
Partial nephrectomy is the mainstay of treatment for localized kidney cancer. A proportion of patients are upstaged post-operatively to locally advanced di 相似文献
8.
Prevalence of Potentially Inappropriate Prescribing Among Hong Kong Older Adults: A Comparison of the Beers 2003, Beers 2012, and Screening Tool of Older Person's Prescriptions and Screening Tool to Alert doctors to Right Treatment Criteria 下载免费PDF全文
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Maher Saqqur MD Michael D. Hill MD MSc FRCPC Andrei V. Alexandrov MD Jayanta Roy MD Marcia Schebel BSc Andrea Krol BSc Zsolt Garami MD Ashfaq Shuaib MD FRCPC Andrew M. Demchuk MD FRCPC 《Journal of neuroimaging》2006,16(4):323-328
BACKGROUND: Stringent transcranial Doppler (TCD) criteria for diagnosing occlusion are needed for more reliable TCD performance at bedside in the acute stroke setting. SUBJECTS AND METHODS: At three academic stroke centers, we performed TCD examination for patients with symptoms of cerebral ischemia who underwent digital subtraction angiography (DSA). We used a standard insonation protocol with power M-mode Doppler (PMD) TCD (TCD 100 M, Spencer Technologies Inc., Seattle, WA). We collected mean flow velocity (MFV), pulsatility indices (PI), and power M-mode resistance signature (absent, high, or low) in symptomatic middle (MCA), anterior (ACA), posterior (PCA), and in affected (a), ipsilateral (i), and contralateral (c-lat) cerebral arteries. Ratios of aMCA/c-lat MCA, aMCA/iACA, and aMCA/iPCA MFV were subsequently calculated. PMD-TCD flow findings were evaluated with a receiver-operating characteristic (ROC) analysis for angiographically proven MCA occlusion. RESULTS: We studied 120 patients with acute cerebral ischemia with PMD-TCD examinations prior to or immediately after DSA. Lower aMCA velocities pointed to higher probability of occlusion (P= .055). The aMCA/iPCA MFV ratio was superior to the aMCA/iACA ratio and strongly predictive of occlusion at a threshold ratio of 0.5 (RR 2.31 CI(95) 2.13-2.51). High resistance or absent M-mode flow signatures in the proximal MCA were present in 87% of M1 and M2 MCA occlusions (probability 87%). In the presence of a low-resistance PMD signature, obtaining the aMCA/iPCA MFV ratio <0.5 increases probability of occlusion to 87%. Normal MFV ratios and low-resistance M-mode signatures are highly predictive of a negative angiogram for MCA occlusion. CONCLUSION: In acute cerebral ischemia, reliable criteria for proximal MCA occlusion have been developed based on combination of MFV ratios and M-mode flow resistance signatures. Validation of these criteria will require multicenter studies. 相似文献