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Confirmatory Test (confirmatory + test)
Selected AbstractsProspective Study of Accuracy and Outcome of Emergency Ultrasound for Abdominal Aortic Aneurysm over Two YearsACADEMIC EMERGENCY MEDICINE, Issue 8 2003Vivek S. Tayal MD Abstract Determination of the presence of an abdominal aortic aneurysm (AAA) is essential in the management of the symptomatic emergency department (ED) patient. Objectives: To identify whether emergency ultrasound of the abdominal aorta (EUS-AA) by emergency physicians could accurately determine the presence of AAA and guide ED disposition. Methods: This was a prospective, observational study at an urban ED with more than 100,000 annual patient visits with consecutive patients enrolled over a two-year period. All patients suspected to have AAA underwent standard ED evaluation consisting of EUS-AA, followed by a confirmatory imaging study or laparotomy. AAA was defined as any measured diameter greater than 3 cm. Demographic data, results of confirmatory testing, and patient outcome were collected by retrospective review. Results: A total of 125 patients had EUS-AA performed over a two-year period. The patient population had the following characteristics: average age 66 years, male 54%, hypertension 56%, coronary artery disease 39%, diabetes 22%, and peripheral vascular disease 14%. Confirmatory tests included radiology ultrasound, 28/125 (22%); abdominal computed tomography, 95/125 (76%); abdominal magnetic resonance imaging, 1/125 (1%); and laparotomy, 1/125 (1%). AAA was diagnosed in 29/125 (23%); of those, 27/29 patients had AAA on confirmatory testing. EUS-AA had 100% sensitivity (95% CI = 89.5 to 100), 98% specificity (95% CI = 92.8 to 99.8), 93% positive predictive value (27/29), and 100% negative predictive value (96/96). Admission rate for the study group overall was 70%. Immediate operative management was considered in 17 of 27 (63%) patients with AAA; ten patients were taken to the operating room. Conclusions: EUS-AA in a symptomatic population for AAA is sensitive and specific. These data suggest that the presence of AAA on EUS-AA should guide urgent consultation. Emergency physicians were able to exclude AAA regardless of disposition from the ED. [source] Problem of Distinguishing False-Positive Tests from Acute or Transient Helicobacter pylori InfectionsHELICOBACTER, Issue 2 2006Zhannat Z. Nugalieva Abstract Background:, Reliable detection of acute Helicobacter pylori infections remains problematic. The high prevalence of false-positive non-invasive tests in low H. pylori prevalence populations makes identification of acute and transient infections difficult. Methods:, We explored the use of serum pepsinogens (PG) for diagnosis of acute infection in patients following H. pylori challenge such that the onset of the infection was known. We then compared those findings to a group of children with presumed acute infections defined as a positive urea breath test (UBT) and negative IgG serology. Results:, We examined the pattern and calculated cut-off values of PG levels in 18 adult volunteers with known acute H. pylori infection. We then compared the results with sera from nine symptomatic children with presumed acute H. pylori infection and a matched control group of nine children who did not meet criteria for acute H. pylori infection. In acute infection, both PGI and II levels increased following H. pylori infection reaching a peak by 2 weeks post-infection. The frequency of a positive test defined as a value > mean +2 SD was 17, 71, and 94% at week 1, 2, and 4 post-infection, respectively. Only one child with presumed acute H. pylori infection had an elevated serum PGI and one had an elevated PGII. Five of the children had follow-up UBTs and four were negative consistent with the diagnosis of false-positive UBT. H. pylori infection was confirmed in the child with an elevated PGI level. Conclusions:, These data suggest that a single positive noninvasive test in populations of low prevalence is most likely a false-positive result. This suggests that a single positive test requires confirmation preferably using a test that measures a different parameter (e.g., UBT confirmed by stool antigen test). It appears that most "transient"H. pylori infections are diagnosed on the basis of false-positive tests. PG levels are possible candidates as the confirmatory test. [source] New immunochemical fecal occult blood test with two-consecutive stool sample testing is a cost-effective approach for colon cancer screening: Results of a prospective multicenter study in Chinese patientsINTERNATIONAL JOURNAL OF CANCER, Issue 12 2006Shirong Li Abstract The purpose of the study is to evaluate a new immunochemical fecal occult blood test method (Hemosure IFOBT), and compare it to the Guaiac-based chemical method (CFOBT) for colorectal cancer detection. A hypothetical sequential method (SFOBT), in which IFOBT was used only as a confirmatory test for CFOBT, was also evaluated. A total of 324 patients were recruited from 5 major hospitals in Beijing, China. For each patient, 3 consecutive stool samples were collected for simultaneous CFOBT and IFOBT tests, followed by colonoscopic examination. We compared the sensitivity and specificity of the 3 methods (CFOBT, IFOBT and SFOBT) in two settings, with the first 2 consecutive samples versus all 3 samples. Although the sensitivity for the detection of cancer and large (>20 mm) or multiple adenoma was similar for all 3 methods in the three-sample setting, in the two-sample setting IFOBT had higher sensitivity than SFOBT for detecting cancer (87.8% vs. 75.5%, respectively, p < 0.05) and large (>20 mm) or multiple adenomas (65.4% vs. 42.3%, respectively, p < 0.05). The IFOBT also had a higher specificity than the CFOBT (89.2% vs. 75.5%, respectively, p < 0.01) in "normal" individuals defined by colonoscopy in the three-sample setting. Comparing two-sample setting to the three-sample setting, both CFOBT and SFOBT showed significant loss of sensitivity for the detection of cancer as well as adenoma, whereas the sensitivity for IFOBT did not change significantly. Overall, IFOBT with two-sample testing showed compatible sensitivity and specificity to the three-sample testing, and had a lower relative cost per cancer detected than the three-sample testing. In conclusion, the new Hemosure IFOBT with two consecutive stool samples appears to be the most cost-effective approach for colon cancer screening. © 2006 Wiley-Liss, Inc. [source] Application of differential display, with in situ hybridization verification, to microscopic samples of breast cancer tissueINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 5 2003Ruey Ho Kao Summary., The technique of differential display (DD) has been used widely to identify potentially interesting overexpressed or repressed genes in a variety of compared samples. When used in studying tissue samples, it inevitably confronts problems of limited amount of input material and cell-type heterogeneity. We report here the application of in situ hybridization as a method of confirmatory test for DD as well as definition of cell type expressing differential cDNA. This procedure employed material derived from a single case of human mammary, grade III, infiltrating ductal carcinoma, using free-hand microdissection, where we have compared gene expression profiles in invasive tumour with those in adjacent normal tissue. A total of 21 cDNAs were found to be differentially expressed between the two tissue types; 11 upregulated in the tumour sample and 10 upregulated in the normal sample. Six cDNAs were utilized as probes for in situ hybridization analysis of a further five cases of comparably staged breast cancer. One of these clones, 11AT1, which was found to be homologous to Hsc70, was shown to be overexpressed in tumour cells relative to adjacent normal stroma and to benign glandular epithelium in all five cases; an increase in expression was further confirmed at protein level by immunohistochemistry. The study demonstrated the applicability of in situ hybridization as a screening test in DD strategy for studying tissue material and a reasonable technique combination of identifying changes in gene expression associated with tumour development. [source] Determination of HLA-A, -B and -DRB1 haplotypes based on allelic homozygosity data in selected bone marrow donors of the Taiwanese marrow donor registryINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 5 2007K. L. Yang Summary From 120 unrelated Taiwanese marrow stem cell donors with allelic homozygosities at human leucocyte antigen (HLA)-A, -B and -DRB1 loci, we determined 85 distinguishable haplotypes. Using the predetermined haplotype data, we deduced 418 haplotypes from 1903 unrelated individual stem cell donors selected for HLA confirmatory test. Eighteen of the 20 (90%) most frequently observed haplotypes determined in Asian Americans using computer prediction were found in this study. In comparison with haplotypes determined by maximum likelihood algorithm in Korean population, 18 of the 29 (62.07%) Korean haplotypes with a frequency over 0.5% were also among the haplotypes determined in this investigation. Randomized family studies confirmed that over 50% of the haplotypes observed in the families were among the haplotypes deduced based on allelic homozygosity, suggesting that proportionally additional haplotypes can be determined as the number of donors being studied is increased. Haplotypes carrying low incidence allele characteristics of Taiwanese were also observed in this study. This established haplotype information will be beneficial for patients searching for stem cell donors in our registry domestically and internationally. [source] Population-based type-specific prevalence of high-risk human papillomavirus infection in middle-aged Swedish WomenJOURNAL OF MEDICAL VIROLOGY, Issue 4 2002Ola Forslund Abstract Human papillomavirus (HPV) DNA testing can be used to identify women at risk of the development of cervical cancer. The cost-effectiveness of HPV screening is dependent on the type-specific HPV prevalence in the general population. The present study describes the prevalence and spectrum of high-risk HPV types found in a large real-life population-based HPV screening trial undertaken entirely within the cervical screening program offered to middle-aged Swedish women. Cervical brush samples from 6,123 women aged 32,38 years were analyzed using a general HPV primer (GP5+/6+) polymerase chain reaction-enzyme immunoassay (PCR-EIA) combined with reverse dot-blot hybridization for confirmation and HPV typing by a single assay. In this study, 6.8% (95% CI 6.2,7.5) (417/6,123) were confirmed as high-risk HPV positive. Infections with 13 different high-risk HPV types were detected, of which HPV 16 was the most prevalent type (2.1%; 128/6,123), followed by HPV 31 (1.1%; 67/6,123). Any one of the HPV types 18, 33, 35, 39, 45, 51, 52, 56, 58, 59, or 66 was detected in 3.6% (223/6,123) of the women. Infection with two, three, and five types simultaneously was identified in 32, 5, and 1 women, respectively. The combination of PCR-EIA as a screening test and reverse dot-blot hybridization as a confirmatory test, was found to be readily applicable to a real-life population-based cervical screening. The type-specific HPV prevalence found support in previous modeling studies suggesting that HPV screening may be a favorable cervical screening strategy. J. Med. Virol. 66:535,541, 2002. © 2002 Wiley-Liss, Inc. [source] Detection of Aflatoxin in Aspergillus Species Isolated from Pistachio in IranJOURNAL OF PHYTOPATHOLOGY, Issue 1 2008P. Rahimi Abstract To estimate the incidence contamination of fresh pistachio nuts by aflatoxigenic fungi in Iran, nut samples were collected from pistachio orchards in Kerman, Rafsanjan and Isfahan regions. Out of the 200 Aspergillus isolates obtained, 11 species were identified as A. alliaceous, A. candidus, A. flavus, A. niger, A. niveus, A. ochraceus, A. parasiticus, A. tamari, A. terreus, A. unguis and A. wentii. For detection of aflatoxin production ability of the isolates, three target genes, namely aflR, aflJ, and omtB, used in PCR amplification. In all the examined cases, the degenerate primer designed for amplification of omtB gene, named omtBII, was able to amplify an expected 611 bp fragment in aflatoxigenic isolates in this study and yielded the same result as those obtained from TLC analysis and fluorescence ability by application of methylated ,-cyclodextrin in culture media. Using this procedure the significant incidence of aflatoxin-producing aspergilli was confirmed in pistachio nuts produced in different regions of Iran. The results indicated that PCR method described here, in combination with fluorescence assay, is a reliable and simple confirmatory test for monitoring pistachio nuts contaminated with aflatoxinogenic aspergilli. [source] Comparative Analysis of Indoor Levels of Suspended Particulates and Nitrogen Dioxide a Few Hours later after an Asthmatic AttackCHINESE JOURNAL OF CHEMISTRY, Issue 11 2007Emmanuel Ehiabhi UKPEBOR Abstract Suspended particulates (TSP) and nitrogen dioxide (NO2) are known respiratory irritants linked to asthma aggravation. This pilot study was designed to investigate the role of these pollutants on the frequency of asthmatic attack on two of the inhabitants of a household. The surveillance of TSP and NO2 in this household commenced a few hours later, after one of the occupants suffered an attack. The TSP load determination was done using a High Volume Gravimetric sampler and a light scattering method via a Haz-Dust 10 µm particulate monitor. Palmes Diffusion tubes for NO2 and a portable Crowcon Gasman toxic gas detector were utilized for NO2 screening. In the first day of monitoring in the living room, the in situ particulate sampler (Haz-Dust) recorded a mean TSP level of 26,000 µg·m,3. A confirmatory test with the eight hour average Gravimetric sampler gave 25,833 µg·m,3. With the use of the Gasman toxic gas detector for NO2, the NO2 concentration for the first few hours of sampling was lower than 188 µg·m,3, the detection limit of this instrument. However, the exact NO2 concentrations for the 7 day monitoring after the attack were 27.50 µg·m,3 (kitchen) and 12.03 µg·m,3 (living room) as recorded by the Palmes diffusion tubes. [source] Medical and legal considerations of brain deathACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2004T. T. Randell Brain death was first defined in 1968, and since then laws on determining death have been implemented in all countries with active organ transplantation programs. As a prerequisite, the aetiology of brain death has to be known, and all reversible causes of coma have to be excluded. The regulations for the diagnosis of brain death are most commonly given by the national medical associations, and they vary between countries. Thus, the guidelines given in the medical textbooks are not universally applicable. The diagnosis is based on clinical examination, but confirmatory tests, such as angiography or EEG, are allowed on most occasions. Brain death is followed by cardiovascular and hormonal changes, which have implications in the management of a potential organ donor. Spinal reflexes are preserved, and motor and haemodynamic responses are frequently observed in brain dead patients. [source] Effect of plant variety, plant age and photoperiod on glandular pubescence and host-plant resistance to potato moth (Phthorimaea operculella) in Lycopersicon spp.ANNALS OF APPLIED BIOLOGY, Issue 2 2001G M GURR Summary The effect of plant age and daylength on glandular pubescence was determined for two lines of tomato derived from Lycopersicon hirsutum (BTN 979 and LA 1777A) and a variety of L. esculentum (N 91-1-1-1-1). Densities of type I, IV, VI and VII glandular trichomes were lowest in N 91-1-1-1-1 and, over all varieties, were more dense on plants aged greater than 6 wk. Daylength interacted with variety to significantly affect densities of type VII trichomes only. Host-plant resistance to Phthorimaea operculella was determined in preliminary tests using insects cultured from founders from a potato crop and in confirmatory tests using (less readily available) insects recovered from foliage of a tomato crop. Mortality of ex-potato neonates on LA 1777 A and BTN 979 foliage was higher 18 h after placement than for N 91-1-1-1-1, with no effect of day length or plant age. Mortality for ex-tomato neonates followed a similar trend. Ten days later, two-thirds of ex-tomato larvae had established mines on N 91-1-1-1-1 but fewer (16.7%) were live on other varieties. Stepwise multiple regression using variety as the sole factor was significant (P<0.001) in accounting for 61.4% of the variation in ex-tomato larval survival but addition of other factors to the regression model was not significant. BTN 979 supported fewer, smaller adults to develop than did N 91-1-1-1-1, whilst no adults developed on LA 1777 A. In a non-choice test using ex-potato adults, significantly more eggs were laid on N 91-1-1-1-1 than on L. hirsutum varieties and 9-wk-old plants were preferred over plants three weeks older or younger. The same variety and plant age trends were evident in a free-choice test using ex-tomato adults. [source] | |||||||||||||