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101.
To effectively implement the Canadian Cardiovascular Society (CCS) guidelines for dyslipidemia management into clinical laboratories, clear recommendations for lipid reporting are essential. In this study, the Canadian Society of Clinical Chemists Working Group on Reference Interval Harmonisation surveyed Canadian laboratories on adult lipid reporting practices to set a foundation for the development and implementation of harmonised lipid reporting across Canada. Key aspects of the survey asked laboratories: what reporting parameters were in place to assess lipid results; what interpretative comments were provided; whether nonfasting lipids were permitted and, if so, what strategy was used to document fasting status; and whether there was interest in implementing a harmonised lipid report. A total of 101 laboratories were represented by 24 respondents, as many responses were submitted by laboratory networks that included more than 1 laboratory. There was at least 1 response from 9 Canadian provinces and representation across 5 testing platforms. Upper and lower limits for lipid parameters and referenced source of limits varied substantially across laboratories, with only 56% of laboratories (9 respondents) referencing the 2016 CCS guidelines. Eighty-six percent of laboratories (19 respondents) report nonfasting lipids, although the method of documenting nonfasting status varied. Overall, 36% of laboratories (8 respondents) reported interest in implementing a harmonised lipid report. Assessment of current lipid-reporting practices supports the need for harmonised lipid reporting across Canada. Development of a harmonised lipid report for the adult population, consistent with up-to-date Canadian guidelines, will improve continuity of lipid test interpretation across Canada and improve clinical decision making.  相似文献   
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OBJECTIVE: To document disease activity and functional status in patients with scleroderma (systemic sclerosis [SSc]) and Raynaud's phenomenon (RP) and to determine the sensitivity to change, reliability, ease of use, and validity of various outcome measures in these patients. METHODS: Patients with SSc and moderate-to-severe RP participating in a multicenter RP treatment trial completed daily diaries documenting the frequency and duration of RP attacks and recorded a daily Raynaud's Condition Score (RCS). Mean scores for the 2-week periods prior to baseline (week 0), end of trial (week 6), and posttrial followup (week 12) were calculated. At weeks 0, 6, and 12, physicians completed 3 global assessment scales and performed clinical assessments of digital ulcers and infarcts; patients completed the Health Assessment Questionnaire (HAQ), the Arthritis Impact Measurement Scales 2 (AIMS2) mood and tension subscales, 5 specific SSc/RP-related visual analog scales (VAS), and 3 other VAS global assessments. We used these measures to document baseline disease activity and to assess their construct validity, sensitivity to change, and reliability in trial data. RESULTS: Two hundred eighty-one patients (248 women, 33 men; mean age 50.4 years [range 18-82 years]) from 14 centers participated. Forty-eight percent had limited cutaneous SSc; 52% had diffuse cutaneous SSc. Fifty-nine patients (21%) had digital ulcers at baseline. Patients had 3.89 +/- 2.33 (mean +/- SD) daily RP attacks (range 0.8-14.6), with a duration of 82.1 +/- 91.6 minutes/attack. RCS for RP activity (possible range 0-10) was 4.30 +/- 1.92. HAQ scores (0-3 scale) indicated substantial disability at baseline (total disability 0.86, pain 1.19), especially among the subscales pertaining to hand function (grip, eating, dressing). AIMS2 mood and tension scores were fairly high, as were many of the VAS scores. Patients with digital ulcers had worse RCS, pain, HAQ disability (overall, grip, eating, and dressing), physician's global assessment, and tension, but no significant difference in the frequency of RP, duration of RP, patient's global assessment, or mood, compared with patients without digital ulcers. VAS scores for digital ulcers as rated by the patients were not consistent with the physician's ratings. Factor analysis of the 18 measures showed strong associations among variables in 4 distinct domains: disease activity, RP measures, digital ulcer measures, and mood/tension. Reliability of the RCS, HAQ pain and disability scales, and AIMS2 mood and tension subscales was high. The RP measures demonstrated good sensitivity to change (effect sizes 0.33-0.76). CONCLUSION: Our findings demonstrate that the significant activity, disability, pain, and psychological impact of RP and digital ulcers in SSc can be measured by a small set of valid and reliable outcome measures. These outcome measures provide information beyond the quantitative metrics of RP attacks. We propose a core set of measures for use in clinical trials of RP in SSc patients that includes the RCS, patient and physician VAS ratings of RP activity, a digital ulcer/infarct measure, measures of disability and pain (HAQ), and measures of psychological function (AIMS2).  相似文献   
104.
In a 2-year study of false-positive anti-HIV-1 tests in blood donors at Manchester and Lancaster Blood Banks, the reactions associated with a HIV-infected cell lysate antigen were compared with those using recombinant-antigen-based tests. In year 1 (cell lysate test) at Manchester BTS 0.21% of 119.178 donations were repeatedly reactive, compared with 0.53% of 119,004 donations in year 2 (recombinant antigen). Reactive sera were tested at Manchester PHL by three different immunoassays. Referred specimens were classified as anti-HIV positive (95-100% reactive in all the assays), equivocal or negative (negative results in all three immunoassays). Two donors were confirmed to be anti-HIV positive over the 2-year period. Most sera were negative by confirmatory immunoassays in years 1 and 2. In year 1, a study of 60 referred sera with sex- and age-matched controls showed high correlation between a reactive anti-HIV-1 screening test and indeterminate anti-HIV-1 patterns on Western blot showing reactions with HIV gag-coded proteins. In year 2, less than 10% of referred sera were reactive by Western blot, and there was no correlation between a reactive screening anti-HIV test, the strength of signal in the test or a reactive Western blot. Follow-up showed that donors whose sera were reactive in years 1 and 2 by the anti-HIV-1 screening test formed almost two different populations. Four donors with equivocal anti-HIV-1 confirmatory tests had anti-HIV 'envelope' reactions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
105.
Exoenzyme S (ExoS), which has been implicated as a virulence factor of Pseudomonas aeruginosa, catalyzes transfer of the ADP-ribose moiety of NAD+ to many eukaryotic cellular proteins. Its preferred substrates include Ras and several other 21- to 25-kDa GTP-binding proteins. ExoS absolutely requires a ubiquitous eukaryotic protein factor, termed FAS (factor activating ExoS), for enzymatic activity. Here we describe the cloning and expression of a gene encoding FAS from a bovine brain cDNA library and demonstrate that purified recombinant FAS produced in Escherichia coli activates ExoS in a defined cell-free system. The deduced amino acid sequence of FAS shows that the protein (245 residues, calculated molecular mass 27,743 Da) belongs to a highly conserved, widely distributed eukaryotic protein family, collectively designated as 14-3-3 proteins. Various functions have been reported for members of the 14-3-3 family, including phospholipase A2 activity and regulation of tyrosine hydroxylase, tryptophan hydroxylase, and, possibly, protein kinase C activities. Identification of FAS as a 14-3-3 protein establishes an additional function for this family of proteins--the activation of an exogenous ADP-ribosyltransferase. Elucidation of the precise role of FAS in activating ExoS will contribute to understanding the molecular mechanisms by which P. aeruginosa causes disease.  相似文献   
106.
An in vitro study indicated that certain antacids and adsorbents may decrease the oral availability of th two widely used antimalarial agents chloroquine and pyrimethamine. To determine if this data was applicable to the clinical (in vivo) situation, plasma levels of one of the antimalarial agents (chloroquine) were followed in six Negro--Arab volunteers both when given alone and when taken with separate doses of two of the implicated interactants (magnesium trisilicate and kaolin). This in vivo work confirmed the in vitro findings; chloroquine area under the plasma concentration-time curve data were decreased by both magnesium trisilicate (18.2%) and kaolin (28.6%). Similar results could be expected for pyrimethamine. It is suggested therefore, to avoid loss of drug, that the antimalarials should not be taken with gastrointestinal medications of this type or that their administration should be separated by at least 4 h to reduce the risk of them interacting in the gut, thus preventing drug adsorption to the antacids/adsorbents, and loss of systemic availability.  相似文献   
107.
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109.
Antagonists of the N-methyl-D-aspartate (NMDA)-type glutamate receptor induce psychosis in healthy individuals and exacerbate schizophrenia symptoms in patients. In this study we have produced an animal model of NMDA receptor hypofunction by chronically treating rats with low doses of the NMDA receptor antagonist MK-801. Subsequently, we performed an expression study and identified 20 genes showing altered expression in the brain of these rats compared with untreated animals. We then explored whether the human orthologs of these genes are associated with schizophrenia in the largest schizophrenia genome-wide association study published to date, and found evidence for association for 4 out of the 20 genes: SF3B1, FOXP1, DLG2 and VGLL4. Interestingly, three of these genes, FOXP1, SF3B1 and DLG2, have previously been implicated in neurodevelopmental disorders.  相似文献   
110.
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study.  相似文献   
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