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1.
Human enteroviruses have traditionally been typed according to neutralization serotype. This procedure is limited by the difficulty in culturing some enteroviruses, the availability of antisera for serotyping, and the cost and technical complexity of serotyping procedures. Furthermore, the impact of information derived from enterovirus serotyping is generally perceived to be low. Enteroviruses are now increasingly being detected by PCR rather than by culture. Classical typing methods will therefore no longer be possible in most instances. An alternative means of enterovirus typing, employing PCR in conjunction with molecular genetic techniques such as nucleotide sequencing or nucleic acid hybridization, would complement molecular diagnosis, may overcome some of the problems associated with serotyping, and would provide additional information regarding the epidemiology and biological properties of enteroviruses. We argue the case for developing a molecular typing system, discuss the genetic basis of such a system, review the literature describing attempts to identify or classify enteroviruses by molecular methods, and suggest ways in which the goal of molecular typing may be realized.  相似文献   

2.
BACKGROUND: Herpesvirus infections of the central nervous system are often severe but are fortunately rare. The incidence of these infections has however, increased in recent years as a consequence of an increase in the number of immune-compromised individuals. New diagnostic procedures have improved our ability to diagnose these infections and herpesviruses may yet be implicated as the cause of further neurological diseases with no known aetiology. Methodological standards for selection and evaluation of patient materials are essential to the provision of reliable diagnosis, yet few studies have addressed this important issue. OBJECTIVES: To describe and define methodological standards and reference methodology for diagnosis of herpesvirus infections of the CNS. STUDY DESIGN: Information gathered by literature review. RESULTS: Only for herpes simplex encephalitis is there sufficient data to allow the definition of reference methodology. Good methodological standards exist but few studies have adhered to these standards. As methods for the detection of specific intrathecal antibody synthesis are well established yet under-used in diagnostic virology, the principle of these measurements is reviewed in some detail. CONCLUSIONS: Herpesvirus infections of the CNS are of increasing importance. High quality, multi-centre studies are needed to establish the value of the new diagnostic test procedures if further improvement in the diagnostic sensitivity and specificity of these procedures is to be achieved.  相似文献   

3.
The detection of intrathecal antibody synthesis was compared by the calculation of antibody indices (AI) derived from ELISA techniques with the detection of virus-specific oligoclonal IgGs by an antigen-mediated capillary blot technique. Twenty-seven paired serum and cerebrospinal fluid (CSF) samples were examined from 15 immunocompetent patients with herpes simplex virus encephalitis (HSE) diagnosed by PCR on early CSF samples. These techniques were also applied to paired samples from 20 multiple sclerosis (MS) patients, 10 patients with other inflammatory neurological diseases and 10 patients with non inflammatory neurological disorders. There was a good correlation between the results obtained by AI and those obtained by immunoblotting, especially in HSE (2 discordant results out of 27). Discrepancies were more frequent (25%) in MS patients where a "polyspecific" reaction characterized by low affinity antibodies is known to occur. Some of the discrepancies could, in part, be due to serological cross-reaction with varicella zoster virus.  相似文献   

4.
OBJECTIVES: To evaluate, in a cohort of 566 patients with systemic lupus erythematosus (SLE) drawn from 11 European centres: (i) the prevalence of ANCAs and their subspecificities in a large series of European SLE patients; (ii) the possible associations of ANCA with the most common clinical manifestations of the disease; and (iii) whether ANCAs correlate with some of the autoantibodies commonly found in SLE. METHODS: ANCA detection was performed by indirect immunofluorescence (IIF), and by ELISA for lactoferrin (LF), myeloperoxydase (MPO), proteinase3 (PR3) and lysozyme (LZ) subspecificities. RESULTS: The prevalence of ANCA was 16.4% (IIF). The prevalence of LF was 14.3%, LZ 4.6%, MPO 9.3%, and PR3 1.7%. Our results show that ANCA is associated with certain clinical manifestations of SLE. In particular, positive correlations were found between IIF ANCA and serositis (p = 0.026), livedo reticularis (p = 0.01), venous thrombosis (p = 0.03) and arthritis (p = 0.04), while anti-LF antibodies were associated with serositis (p = 0.05) and livedo reticularis (p < 10(-3). Nevertheless, multivariate analysis demonstrated that other autoantibodies, such as aCL and SSA/Ro, are more closely correlated than ANCA with some of the aforementioned clinical features. CONCLUSION: Our results demonstrate that ANCA are detectable in SLE sera and that some of them are associated with particular clinical manifestations. Whether ANCA plays a direct pathogenetic role in the vascular damage of SLE or only represents an epiphenomenon or a marker of disease activity remains to be elucidated.  相似文献   

5.
BACKGROUND: Disturbances of the fibrinolytic system that lead to decreased removal of fibrin deposits may be important risk factors for coronary thrombosis. There is as yet no consensus on the prognostic value of fibrinolytic parameters, which may be attributed in part to the choice of confounding variables controlled for. METHODS AND RESULTS: The ECAT study is a prospective multicenter study of 3043 patients with angina pectoris followed for 2 years. Baseline measurements included 10 fibrinolytic variables. The results were analyzed in relation to the subsequent incidence of myocardial infarction or sudden coronary death. They are presented before and after adjustment for clusters of confounding variables that are markers of different mechanisms: insulin resistance (body mass index, triglyceride, and HDL cholesterol), inflammation (fibrinogen and C-reactive protein), and endothelial cell damage (von Willebrand factor). An increased incidence of events was associated with higher baseline concentrations of tissue plasminogen activator (TPA) antigen (P = .0002), plasminogen activator inhibitor-1 (PAI-1) activity (P = .02), and PAI-1 antigen (P = .001). The associations of PAI-1 activity and PAI-1 antigen with risk of events disappeared after adjustment for parameters reflecting insulin resistance but were not affected by other adjustments. TPA antigen was affected to a similar extent by adjustment for parameters reflecting insulin resistance. Inflammation, or endothelial cell damage, but the risk association disappeared only after combined adjustments. CONCLUSIONS: The prognostic role of PAI-1 in predicting coronary events is related principally to insulin resistance, whereas that of TPA antigen could be explained only by its relationship with different mechanisms, including insulin resistance, inflammation and endothelial cell damage.  相似文献   

6.
We have developed the AMPLICOR CMV Test, which is rapid and sensitive for the detection of cytomegalovirus (CMV) in plasma and cerebrospinal fluid (CSF) specimens. The test incorporated an internal control in the reaction mixture to monitor the amplification efficiency and the presence of inhibitors. The AMPLICOR CMV Test was very specific in detecting 12 clinical CMV isolates and four laboratory CMV strains tested. Cross-reactivity with 26 non-CMV pathogens was not observed. The AMPLICOR CMV Test requires only 50 microl of specimen (plasma or CSF) for processing. The performance of the AMPLICOR CMV Test was compared to those of the CMV antigenemia assay and the conventional tube culture method. Among 112 plasma specimens from 43 human immunodeficiency virus-infected patients, CMV was detected in 20 (18%) of the specimens by the AMPLICOR CMV Test, 21 (19%) of the specimens by the CMV antigenemia assay, and 10 (9%) of the specimens by culture. In CSF specimens from AIDS patients, CMV was detected in 10 of 58 (17%) specimens tested by the AMPLICOR CMV Test, 5 of 28 (18%) specimens tested by the antigen assay, and none of the 25 specimens tested by culture. While the performance of the AMPLICOR CMV Test in this study was comparable to that of the CMV antigen assay, processing of specimens by the AMPLICOR CMV Test was much simpler than that by the antigen assay; in addition, the antigen assay requires greater than 10(5) leukocytes from blood or 1 ml of CSF to perform the assay. Our study suggested that the AMPLICOR CMV Test could provide a rapid and sensitive assay for the detection of CMV in plasma and CSF specimens.  相似文献   

7.
The plasminogen activation (PA) system is involved in the breakdown and remodelling of the extracellular matrix. In the case of cancer, this is a prerequisite for invasion and metastasis. The expression of urokinase-type plasminogen activator and plasminogen activator inhibitor type 1 in particular have been reported to be of clinical and prognostic value. This has primarily been proven in the case of breast carcinoma and colon carcinoma, using the enzyme-linked immunosorbent assay (ELISA) as a quantitative assay to determine the level of expression. Immunohistochemistry is another technique to investigate the presence of PA components. It allows assessment in a semiquantitative way and informs in addition on the specific distribution within the tissue. To take full advantage of the benefits of immunohistochemistry, it is important to aim at optimal quality in all steps influencing the final judgement of the staining results. These various steps are highlighted and discussed in this paper.  相似文献   

8.
In viral meningitis the inflammatory response involves activated T cells and monocytes which are recruited into the subarachnoid space. To identify the chemotactic signals attracting the cells to the site of infection in the meninges, we measured the levels of two CXC chemokines, interferon-gamma (IFN-gamma) inducible protein (IP)-10 and monokine induced by IFN-gamma, four CC chemokines, monocyte chemotactic protein (MCP)-1, RANTES, macrophage inflammatory protein (MIP)-1 alpha and MIP-1 beta, as well as the cytokines interleukin (IL)-15 and IL-16 in the cerebrospinal fluid (CSF) of patients suffering from viral meningitis. The results point to an involvement of two chemokines, MCP-1 and IP-10, since (1) unlike the other cytokines, MCP-1 and IP-10 were present in 97% and 79% of the CSF, respectively, at concentrations sufficient to induce chemotaxis of mononuclear cells; (2) more than 90% of the CSF of viral meningitis induced chemotaxis of peripheral blood mononuclear cells (PBMC) and all of them induced chemotaxis of activated T cells, and (3) the CSF-mediated chemotaxis of PBMC was inhibited by anti-MCP-1 antibodies and chemotaxis of activated T cells was abolished by the combination of anti-MCP-1 and anti-IP-10 antibodies. Our data provide evidence that MCP-1 and IP-10 lead to accumulation of activated T cells and monocytes in the CSF compartment in viral meningitis.  相似文献   

9.
Data from two published and one new meta-analysis were reviewed to compare the antiemetic efficacy of three different anaesthetic regimens: (i) propofol anaesthesia compared with another anaesthetic (control); (ii) anaesthesia without nitrous oxide compared with the same anaesthetic with nitrous oxide (control); (iii) propofol anaesthesia without nitrous oxide (TIVA) compared with another anaesthetic with nitrous oxide (control). Efficacy (prevention of postoperative nausea and vomiting compared with control) was estimated using odds ratio and number-needed-to-treat methods, and compared within a range of 20-60% control event rates for early efficacy (0-6 h) and 40-80% for late efficacy (0-48 h). Propofol anaesthesia or omitting nitrous oxide had similar effects on vomiting, both early and late. Propofol (but not omitting nitrous oxide) decreased the incidence of nausea. TIVA studies were documented poorly; appropriate comparison with other interventions were not possible. Efficacy of treatments should be compared within a setting-specific range of control event rates. There is insufficient evidence that TIVA with propofol is an anaesthetic technique with a low emetogenic potency.  相似文献   

10.
The quality parameters for the detection of microsporidia in identical sets of 50 stool samples were determined for six laboratories where technicians used light microscopy and for six laboratories where technicians used PCR. The average overall sensitivities were 67% (89% for patient samples only) for the PCR laboratories and 54% (80% for patient samples only) for the light microscopy laboratories. Specificities were 98 and 95%, respectively. Differences in results were most apparent between the individual laboratories rather than between the two major methods used.  相似文献   

11.
Cell fate determination in the developing vertebrate retina is characterized by the sequential generation of seven classes of cells by multipotent progenitor cells. Despite this order of genesis, more than one cell type is generated at any time; for example, in the rat, several cell types are born during the prenatal period, while others are born postnatally. In order to examine whether there are classes of progenitor cells with distinct developmental properties contributing to this developmental progression, we examined antigen expression in progenitor cells during rat retinal development. Two markers of amacrine and horizontal cells, the VC1.1 epitope and syntaxin, were found to be expressed on a subset of progenitors in a temporally regulated manner that closely paralleled the birthdays of these cell types. In order to investigate which cell types were produced by the progenitors expressing these markers, fluorescent latex microspheres covalently coupled to VC1.1 antibodies were used to indelibly label VC1.1+ progenitor cells and their progeny. Early in retinal development, VC1.1+ progenitors generated a high percentage of amacrine and horizontal cells, but no cone photoreceptors. During this same period, a comparable number of cone photoreceptors were generated by VC1.1- progenitors. In the late embryonic and early postnatal period, VC1.1+ progenitors continued to generate predominantly amacrine cells, but also gave rise to an increasing number of rod photoreceptors. These findings demonstrate that expression of these two markers by progenitors is highly correlated with a bias towards the production of amacrine and horizontal cells. The fact that subsets of progenitors with temporally regulated and distinct biases are intermingled within the retinal neuroepithelium provides a basis for understanding how different cell types are generated both simultaneously and in a particular order by multipotent progenitors during retinal development.  相似文献   

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14.
In order to decide whether a plastic food packaging material complies with the European Communities (EC) regulation on migration, a quick analysis of two functional classes of plastics additives (aromatic antioxidants and antistatic agents) from polyolefin materials by 1H-NMR and UV-visible spectrophotometry is presented. The scope of spectroscopic methods for alternative and migration tests is presented. 1H-NMR can be used in several ways, from a simple fingerprint of the potential migrants to an identification procedure. Extraction is optimized using UV spectrophotometry. Optimization relies on extraction kinetics, which include the demonstration that extraction is more severe than migration. Only a few hours are required to conclude whether a material complies with the regulation. The specific migration limits are expressed as specific absorbance limit values, alpha. These data can be annexed by food industries to specifications of a plastic packaging material.  相似文献   

15.
For the application of the tetrade-test in the evaluation of sensory test panel members some principles are mentioned and some interpretations are given.  相似文献   

16.
17.
In many bioartificial liver systems currently being designed and evaluated for use in fulminant hepatic failure, direct contact is required between the patient's blood and the liver cells in the device. The efficacy of such devices will be influenced by the interaction of fulminant hepatic failure (FHF) patient serum with the cells. We have found that FHF serum inhibits the growth rate and the synthesis of DNA, RNA, and protein; disturbs glutathione homeostasis; and induces morphological changes in cultured human Hep G2 cells. These interactions should influence the design of bioartificial liver devices based on proliferating cell lines and indicate the requirement to pretreat FHF patient plasma to reduce the toxin load.  相似文献   

18.
Burden of care, expressed emotion (EE), causal attributions, and salivary cortisol were assessed in 100 carers of patients with Alzheimer's disease. Forty-one carers were rated high EE, which was associated with higher scores of carer distress and strain, and greater reports of noncognitive features in the patient, but not with cortisol levels. High EE carers made more attributions personal to, and controllable by, the patient for negative events. Critical carers made more attributions of the patient's behavior that was idiosyncratic. Warmth toward the patient was associated with the opposite of this pattern. Overinvolved carers made attributions of the patient's behavior to causes external to the patient and internal to themselves. Cortisol levels were associated with self-reports of strain and distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
Patients with unstable angina, refractory to intensive medical therapy, are at high risk for developing thrombotic complications, such as recurrent ischemia, myocardial infarction and coronary occlusion during coronary angioplasty. As both platelet aggregation and/or thrombus formation play an important role in this ongoing ischemic process, a monoclonal platelet GPIIb/IIIa receptor antibody (c7E3) or thrombolytic therapy (alteplase) might be able to modify the clinical course and underlying coronary lesion morphology. To evaluate whether alteplase or c7E3 could influence the incidence of complications, we randomized 36 and 60 patients, respectively to alteplase or placebo, or c7E3 or placebo. All patients exhibited dynamic ECG changes and recurrent pain attacks, despite maximal tolerated medical therapy. Patients were randomized in both studies after initial angiography had demonstrated a culprit lesion amenable for angioplasty. After study drug infusion quantitative angiography was repeated and angioplasty performed. Recurrent ischemia during study drug infusion occurred in 5, 6, 9 and 16 patients from the alteplase, placebo, c7E3 and placebo group, respectively. Major events defined as death, myocardial infarction or urgent intervention occurred in 7, 3, 1 and 7 patients, respectively. Two patients died: one in the alteplase group and one in the placebo group from the c7E3 study. The first patient due to retroperitoneal hemorrhage, the second as a result of recurrent infarction. Qualitative angiography showed resolution of clots in the c7E3 group only, while the same group of patients showed in 20% an improvement in TIMI flow grade, without deterioration in any patient from this group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
To determine whether patients with a HLA-identical sibling donor have a better outcome than patients without a donor, an analysis on the basis of intention-to-treat principles was performed within the framework of the EORTC-GIMEMA randomized phase III AML 8A trial. Patients in complete remission (CR) received one intensive consolidation course. Patients with a histocompatible sibling donor were then allocated allogeneic bone marrow transplantation (alloBMT), the patients without a donor were randomized between autologous BMT (ABMT) and a second intensive consolidation (IC2). 831 patients <46 years old and alive >8 weeks from diagnosis were included. HLA typing was performed in 672 patients. AlloBMT was performed during CR1 in 180 (61%) out of 295 patients with a donor. Another 38 patients were allografted: five in resistant disease, 14 during relapse and 19 in CR2. ABMT was performed in 130 (34%) out of 377 patients without a donor in CR1, in six (2%) patients during relapse and in 38 (10%) patients during CR2. The disease-free survival (DFS) from CR for patients with a donor was significantly longer than for patients without a donor (46% v 33% at 6 years; P=0.01, RR 0.78, 95% confidence interval 0.63-0.96). The overall survival from diagnosis for patients with a donor was longer, but not statistically significant, than for patients without a donor (48% v 40% at 6 years; logrank P=0.24). When patients were stratified according to prognostic risk groups, the same trend in favour of patients with a donor was seen for survival duration and the DFS remained significantly longer for this group of patients.  相似文献   

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