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Highest Sensitivity (highest + sensitivity)
Selected AbstractsAn Independent Evaluation of Four Quantitative Emergency Department Crowding ScalesACADEMIC EMERGENCY MEDICINE, Issue 11 2006Spencer S. Jones MStat Background Emergency department (ED) overcrowding has become a frequent topic of investigation. Despite a significant body of research, there is no standard definition or measurement of ED crowding. Four quantitative scales for ED crowding have been proposed in the literature: the Real-time Emergency Analysis of Demand Indicators (READI), the Emergency Department Work Index (EDWIN), the National Emergency Department Overcrowding Study (NEDOCS) scale, and the Emergency Department Crowding Scale (EDCS). These four scales have yet to be independently evaluated and compared. Objectives The goals of this study were to formally compare four existing quantitative ED crowding scales by measuring their ability to detect instances of perceived ED crowding and to determine whether any of these scales provide a generalizable solution for measuring ED crowding. Methods Data were collected at two-hour intervals over 135 consecutive sampling instances. Physician and nurse agreement was assessed using weighted , statistics. The crowding scales were compared via correlation statistics and their ability to predict perceived instances of ED crowding. Sensitivity, specificity, and positive predictive values were calculated at site-specific cut points and at the recommended thresholds. Results All four of the crowding scales were significantly correlated, but their predictive abilities varied widely. NEDOCS had the highest area under the receiver operating characteristic curve (AROC) (0.92), while EDCS had the lowest (0.64). The recommended thresholds for the crowding scales were rarely exceeded; therefore, the scales were adjusted to site-specific cut points. At a site-specific cut point of 37.19, NEDOCS had the highest sensitivity (0.81), specificity (0.87), and positive predictive value (0.62). Conclusions At the study site, the suggested thresholds of the published crowding scales did not agree with providers' perceptions of ED crowding. Even after adjusting the scales to site-specific thresholds, a relatively low prevalence of ED crowding resulted in unacceptably low positive predictive values for each scale. These results indicate that these crowding scales lack scalability and do not perform as designed in EDs where crowding is not the norm. However, two of the crowding scales, EDWIN and NEDOCS, and one of the READI subscales, bed ratio, yielded good predictive power (AROC >0.80) of perceived ED crowding, suggesting that they could be used effectively after a period of site-specific calibration at EDs where crowding is a frequent occurrence. [source] Comparison of antibodies to HBME-1 and calretinin for the detection of mesothelial cells in effusion cytology ,DIAGNOSTIC CYTOPATHOLOGY, Issue 3 2001Patricia A. Fetsch M.T. (A.S.C.P.) Abstract The distinction of mesothelial cells in cytologic samples is often a diagnostic challenge. This is particularly true in potentially malignant effusions in which reactive mesothelial cells may simulate adenocarcinoma (ACA) cells, and in the differentiation of ACA vs. mesothelioma. We sought to determine the superior antibody for the positive identification of mesothelial cells in these circumstances. Cell block sections of 25 reactive and 8 malignant mesothelioma effusions were immunostained with an avidin-biotin procedure, using antibodies to HBME-1 and calretinin. No pretreatment of samples was necessary for the HBME-1-stained slides; microwave antigen retrieval was performed on all slides stained for calretinin. A negative control was performed on each sample. The staining intensity of tumor cells was scored on a scale of 0,3+, with the proportion of immunoreactive cells categorized as <25%, 25,50%, 50,75%, and >75%. The predominant staining pattern for HBME-1 was surface, with rare samples also exhibiting cytoplasmic staining as well. The calretinin-staining pattern was cytoplasmic, with peripheral condensation/prominence and accompanying nuclear staining. All samples were immunoreactive with both antibodies. Fifty-five percent (18/33) of samples showed significantly stronger immunoreactivity with calretinin than with HBME-1; 45% (15/33) of samples showed equivalent staining with the two markers. None of the samples in this study showed stronger immunoreactivity with HBME-1 than with calretinin. Sixty-one percent (20/33) of samples stained with HBME-1 at a moderate (2+) intensity. Fifty-five percent (18/33) of samples stained with calretinin at a strong (3+) intensity. While only 12% of samples showed >75% immunoreactivity for HBME-1, 58% of samples showed >75% of cells immunoreactive for calretinin. Calretinin is the preferred marker in identifying mesothelial cells in cytologic samples, showing the highest sensitivity for mesothelial cells, as evidenced by a more intense staining reaction in a higher percentage of cells than with HBME-1. Diagn. Cytopathol. 2001;25:158,161. Published 2001 Wiley-Liss, Inc. [source] Predictive factors for esophageal stenosis after endoscopic submucosal dissection for superficial esophageal cancerDISEASES OF THE ESOPHAGUS, Issue 7 2009H. Mizuta SUMMARY Endoscopic submucosal dissection (ESD) has been utilized as an alternative treatment to endoscopic mucosal resection for superficial esophageal cancer. We aimed to evaluate the complications associated with esophageal ESD and elucidate predictive factors for post-ESD stenosis. The study enrolled a total of 42 lesions of superficial esophageal cancer in 33 consecutive patients who underwent ESD in our department. We retrospectively reviewed ESD-associated complications and comparatively analyzed regional and technical factors between cases with and without post-ESD stenosis. The regional factors included location, endoscopic appearance, longitudinal and circumferential tumor sizes, depth of invasion, and lymphatic and vessel invasion. The technical factors included longitudinal and circumferential sizes of mucosal defects, muscle disclosure and cleavage, perforation, and en bloc resection. Esophageal stenosis was defined when a standard endoscope (9.8 mm in diameter) failed to pass through the stenosis. The results showed no cases of delayed bleeding, three cases of insidious perforation (7.1%), two cases of endoscopically confirmed perforation followed by mediastinitis (4.8%), and seven cases of esophageal stenosis (16.7%). Monovalent analysis indicated that the longitudinal and circumferential sizes of the tumor and mucosal defect were significant predictive factors for post-ESD stenosis (P < 0.005). Receiver operating characteristic analysis showed the highest sensitivity and specificity for a circumferential mucosal defect size of more than 71% (100 and 97.1%, respectively), followed by a circumferential tumor size of more than 59% (85.7 and 97.1%, respectively). It is of note that the success rate of en bloc resection was 95.2%, and balloon dilatation was effective for clinical symptoms in all seven patients with post-ESD stenosis. In conclusion, the most frequent complication with ESD was esophageal stenosis, for which the sizes of the tumor and mucosal defect were significant predictive factors. Although ESD enables large en bloc resection of esophageal cancer, practically, in cases with a lesion more than half of the circumference, great care must be taken because of the high risk of post-ESD stenosis. [source] SECM Visualization of Spatial Variability of Enzyme-Polymer Spots.ELECTROANALYSIS, Issue 19-20 20062: Complex Interference Elimination by Means of Selection of Highest Sensitivity Sensor Substructures, Artificial Neural Networks Abstract Polymer spots with entrapped glucose oxidase were fabricated on glass surfaces and the localized enzymatic response was subsequently visualized using scanning electrochemical microscopy (SECM) in the generator,collector mode. SECM images were obtained under simultaneous variation of the concentration of glucose (0,6,mM) and ascorbic acid (0,200,,M), or, in a second set of experiments, of glucose (0,2,mM) and 2-deoxy- D(+)-glucose (0,4,mM). Aiming at the quantification of the mixture components discretization of the response surfaces of the overall enzyme/polymer spot into numerous spatially defined microsensor substructures was performed. Sensitivity of sensor substructures to measured analytes was calculated and patterns of variability in the data were analyzed before and after elimination of interferences using principal component analysis. Using artificial neural networks which were fed with the data provided by the sensor substructures showing highest sensitivity for glucose, glucose concentration could be calculated in solutions containing unknown amounts of ascorbic acid with a good accuracy (RMSE 0.17,mM). Using, as an input data set, measurements provided by sensing substructures showing highest sensitivity for ascorbic acid in combination with the response of the sensors showing highest dependence on the glucose concentration, the error of the ascorbic acid concentration calculation in solution containing the unknown amount of glucose was 10,,M. Similarly, prediction of the glucose concentration in the presence of 2-deoxy- D(+)-glucose was possible with a RMSE of 0.1,mM while the error of the calculation of 2-deoxy- D(+)-glucose concentrations in the presence of unknown concentrations of glucose was 0.36,mM. [source] Application of polymeric surfactants in micellar electrokinetic chromatography-electrospray ionization mass spectrometry of benzodiazepines and benzoxazocine chiral drugsELECTROPHORESIS, Issue 5-6 2006Jingguo Hou Abstract Chiral micellar EKC (CMEKC) coupled to ESI-MS using polymeric surfactants as pseudostationary phases is investigated for simultaneous enantioseparation of two benzodiazepines, (±)-oxazepam ((±)-OXA) and (±)-lorazepam ((±)-LOR), and one benzoxazocine, (±)-nefopam ((±)-NEF). First, enantioselectivity and electrospray sensitivity of six chiral polymeric surfactants for all three chiral compounds are compared. Second, using poly(sodium N -undecenoyl- L -leucinate) as pseudostationary phase, the organic modifiers (methanol (MeOH), isopropanol, and ACN) are added into the running buffer to further improve chiral resolution (RS). Next, a CMEKC-ESI-MS method for the simultaneous enantioseparation of two benzodiazepines is further developed by using a dipeptide polymeric surfactant, poly(sodium N -undecenoxy carbonyl- L,L -leucyl-valinate) (poly- L,L -SUCLV). The CMEKC conditions including nebulizer pressure, capillary length, ammonium acetate concentration, pH, poly- L,L -SUCLV concentration, and capillary temperature were optimized to achieve maximum chiral RS and highest sensitivity of MS detection. The spray chamber parameters (drying gas temperature and drying gas flow rate) as well as sheath liquid conditions (MeOH content, pH, flow rate, and ionic strength) were found to significantly influence MS S/N of both (±)-OXA and (±)-LOR. Finally, a comparative study between simultaneous UV and MS detection showed high plate numbers, better chiral RS, and enhanced detectability with CMEKC-MS. However, speed of analysis was faster using CMEKC-UV. [source] Characterization of the PCR inhibitory effect of bile to optimize real-time PCR detection of Helicobacter speciesFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2005Waleed Abu Al-Soud Abstract The inhibitory effect of human and porcine bile samples to detect Helicobacter DNA was studied by adding different concentrations of bile samples to PCR mixtures of six thermostable DNA polymerases containing cagA specific primers and Helicobacter pylori DNA. PCR products were amplified by using the Rotorgene system and SYBR Green I. Among the six DNA polymerases tested, rTth had the lowest sensitivity to bile inhibitors, whereas Taq and Tfl had the highest sensitivity. Bile proteins did not inhibit AmpliTaq DNA polymerase, whereas the fraction containing mainly bile acids and their salts inhibited the amplification capacity of AmpliTaq. Heating human bile at 98 °C and adding casein and formamide to the reaction mixture reduced the PCR inhibitory effect of bile. Therefore, a pre-PCR treatment based on dilution and heating of bile, adding casein and formamide to the reaction mixture of rTth DNA polymerase was found efficient to amplify DNA directly in bile. [source] Psychrotolerant and microaerophilic bacteria in boreal groundwaterFEMS MICROBIOLOGY ECOLOGY, Issue 1 2002M.K. Männistö Abstract Growth temperature and microaerophily of 39 phylogenetically different isolates from boreal oxygen-deficient groundwater were studied. Based on growth temperatures, the isolates were mainly psychrotolerant bacteria as 35 grew at 2°C and only three at 35°C. Growth rates in the range of 4,35°C fitted the Ratkowsky square root model well. Optimum temperatures of the groundwater isolates varied between 18 and 30°C. In semisolid glucose and PYGV media, 59% and 28% of the isolates, respectively, preferred microaerophilic growth and 33% were catalase-negative. The microaerophilic isolates had the highest sensitivity to H2O2 whereas sensitivity to the superoxide generator paraquat was similar among microaerophilic and aerobic isolates. The results show that the cold (6,8°C) and oxygen-deficient groundwater harbors psychrotolerant and microaerophilic bacteria of different phylogenetic origins which are well adapted to their environment. [source] The role of genotype-specific human papillomavirus detection in diagnosing residual cervical intraepithelial neoplasiaINTERNATIONAL JOURNAL OF CANCER, Issue 2 2002Ruud LM Bekkers Abstract We assessed prospectively whether residual cervical intraepithelial neoplasia (CIN) after treatment for high-grade CIN can be predicted by genotype-specific high-risk HPV (HR-HPV) detection in follow-up cervical scrapes. A broad spectrum, highly sensitive SPF10 -LiPA-PCR HPV detection technique was used on cervical scrapes before large loop excision of the transformation zone (LLETZ), on the LLETZ biopsy and on follow-up scrapes of 90 patients treated for high-grade CIN. HR-HPV was detected in the biopsies of 93% (n = 84) of the patients and in the follow-up scrapes of 48% (n = 43) of the patients. In 12 patients, genotype-specific HR-HPV persistence was detected in both follow-up scrapes. In 10 patients, residual CIN was detected. In 5 of these patients (including all patients with residual CIN 3), the follow-up scrapes showed genotype-specific HR-HPV persistence. In 2 patients, a different HR-HPV was detected, and 3 patients had HR-HPV-negative follow-up scrapes. Conventional cytologic follow-up was abnormal in 13 patients including all 10 patients with residual CIN. The negative predictive value (NPV) of HR-HPV detection on follow-up scrapes was high (94%). Repeat detection of genotype-specific HR-HPV showed a lower sensitivity and NPV than repeat detection of any HR-HPV, but its specificity was higher. Repeat conventional cytologic follow-up showed the highest sensitivity and NPV. In conclusion, the presence of HR-HPV in cervical scrapes after LLETZ for high-grade CIN is a risk factor for the presence of residual CIN. HR-HPV genotype-specific persistence is specifically present in patients with residual CIN 3. However, HR-HPV detection cannot predict or exclude the presence of residual CIN in the individual patient and additional procedures remain necessary. © 2002 Wiley-Liss, Inc. [source] Use of a new silica clotting time for diagnosing lupus anticoagulant in patients who meet the clinical criteria for antiphospholipid syndromeJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 1 2006Panagiotis Grypiotis Abstract The silica clotting time (SCT) is a phospholipid-dependent coagulation assay used for the laboratory diagnosis of lupus anticoagulant (LA) antibodies. The sensitivity and specificity of a new commercial SCT for identifying LA in patients who meet the clinical criteria for antiphospholipid syndrome (APS), and its association with thrombotic events were evaluated here. Forty-five patients who met the clinical criteria for APS according to the Sapporo International Consensus Statement were examined. Sixty-nine patients who did not meet the clinical criteria for APS, and 20 blood donors were used as controls. Plasma samples from the patients and controls were tested for LA using a new commercial SCT with low and high synthetic phospholipid concentrations. The results were compared with those obtained by diluted Russell's viper venom time (dRVVT) and activated partial thromboplastin time (APTT). SCT's sensitivity for identifying LA in patients who met the clinical criteria of APS was higher compared to APTT and dRVVT (53.3% vs. 31.1% and 31.1%), and the specificities of these assays were 96.6%, 100%, and 98.9%, respectively. When dRVVT was combined with SCT, and dRVVT was combined with APTT their sensitivities were 57.7% and 48.8%, and their specificities were 96.6% and 98.9%, respectively. A stepwise logistic regression analysis indicated that the combination of dRVVT with SCT was associated with total thrombotic events (odds ratio (OR)=11.5, 95% confidence interval (CI)=1.25,106.3, P=0.031) as well as with venous thrombosis (OR=4.09, 95% CI=1.16,14.43, P=0.028). According to our results, SCT is the most sensitive assay for identifying LA in patients who meet the clinical criteria for APS. Moreover, the highest sensitivity was reached with a combination of SCT and dRVVT. The method's association with total thrombotic events and venous thrombosis was in fact significant. J. Clin. Lab. Anal. 20:15,18, 2006. © 2006 Wiley-Liss, Inc. [source] Sensitivity and specificity of current diagnostic tests for gill-associated virus in Penaeus monodonJOURNAL OF FISH DISEASES, Issue 11 2006J Munro Abstract This study reports the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy between a reverse transcriptase-nested polymerase chain reaction (RT-nPCR) and an enzyme-linked immunosorbent assay (ELISA) for the detection of gill-associated virus (GAV) from a sample of 120 Penaeus monodon. Subsequently, the same comparisons were applied to the ELISA and haemagglutination (HA) assays for detection of GAV from a second 120 prawns. The optical density (OD) or dilution cut-off point had a direct influence on the tested parameters. The cut-off OD of 0.5,0.6 with the ELISA produced a sensitivity of 98% compared with RT-nPCR. However, these OD produced the lowest accuracy (85.8% and 86.7%, respectively). The OD cut off of 0.75 resulted in the highest accuracy (91.7%) and NPV (81.3%) while it had the second highest sensitivity (97%) and PPV (93.3%). However, the OD cut off of 0.9 had the highest specificity (80%). With regards to HA, the titre cut off at 8 resulted in the highest sensitivity, specificity and NPV (94%, 100% and 100%, respectively) compared with the ELISA, while the HA titre of 16 gave the highest accuracy (73%) and the second highest specificity (75%). A HA titre of 64 gave the highest PPV (81%). Using the RT-nPCR as the gold standard, the ELISA had an accuracy of 91.7% when using a cut off >0.75 as a positive result. When compared with the ELISA, the HA had an accuracy of 73% when using an HA titre cut off greater than 16 as a positive result. These results indicate that alternative tests for GAV (ELISA and HA) can be used to explore multiple questions about the disease status of P. monodon stocks in a cost-effective manner. [source] Des-,-carboxyprothrombin, ,-fetoprotein and AFP-L3 in patients with chronic hepatitis, cirrhosis and hepatocellular carcinomaJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 10 2008Francisco A Durazo Abstract Background and Aim:, Hepatocellular carcinoma (HCC) is a common complication in patients with chronic viral hepatitis. Detection of HCC at an early stage is critical for a favorable clinical outcome. The study aim was to: (i) compare the levels of des-,-carboxyprothrombin (DCP), ,-fetoprotein (AFP) and AFP-L3 in HCC patients and in chronic viral hepatitis patients without HCC; (ii) define the level of each tumor marker with the best sensitivity and specificity for HCC diagnosis; and (iii) to correlate the levels of these markers with respect to size and tumor burden. Methods:, Two hundred and forty patients with either hepatitis B virus (HBV) or hepatitis C virus (HCV) infection were studied. These included 144 with HCC, 47 with chronic hepatitis (fibrosis stage I,III on liver biopsy) and 49 with cirrhosis. Results:, Levels of DCP, AFP and AFP L-3 were significantly higher in patients with HCC than in those without HCC (P , 0.0001). Receiver,operating curves (ROC) indicated that the cut-off value with the best sensitivity and specificity for each test was ,84 mAU/mL for DCP, ,25 ng/mL for AFP and ,10% for AFP-L3. The sensitivity, specificity and positive predictive value (PPV) for DCP was 87%, 85% and 86.8%, for AFP 69%, 87% and 69.8%, and for AFP-L3 56%, 90% and 56.1%, respectively. DCP levels were below the ROC cut-off in all patients without HCC. In patients with single lesions, there was a direct correlation of DCP to tumor size. High levels of AFP correlated with diffuse type of HCC. All three markers were significantly elevated in the presence of metastatic HCC. No advantage was observed by combining two or three markers for HCC diagnosis. Conclusion:, DCP had the highest sensitivity and PPV for HCC diagnosis, had a direct correlation with tumor size, and was not elevated in any patients without HCC. DCP should be used as the main serum test for HCC detection. [source] Sensory-motor function of human periodontal mechanoreceptors,JOURNAL OF ORAL REHABILITATION, Issue 4 2006M. TRULSSON summary, Natural teeth are equipped with periodontal mechanoreceptors that signal information about tooth loads. In the present review, the basic force-encoding properties of human periodontal receptors will be presented along with a discussion about their likely functional role in the control of human mastication. Microneurographic recordings from single nerve fibres reveal that human periodontal receptors adapt slowly to maintained tooth loads. Most receptors are broadly tuned to the direction of force application, and about half respond to forces applied to more than one tooth. Populations of periodontal receptors, nevertheless, reliably encode information about both the teeth stimulated, and the direction of forces applied to the individual teeth. Information about the magnitude of tooth loads is made available in the mean firing rate response of periodontal receptors. Most receptors exhibit a markedly curved relationship between discharge rate and force amplitude, featuring the highest sensitivity to changes in tooth load at very low force levels (below 1 N for anterior teeth and 4 N for posterior teeth). Thus, periodontal receptors efficiently encode tooth load when subjects contact and gently manipulate food using the teeth. It is demonstrated that signals from periodontal receptors are used in the fine motor control of the jaw and it is clear from studies of various patient groups (e.g. patients with dental implants) that important sensory-motor functions are lost or impaired when these receptors are removed during the extraction of teeth. [source] Facing the challenge of biosample imaging by FTIR with a synchrotron radiation sourceJOURNAL OF SYNCHROTRON RADIATION, Issue 1 2010Cyril Petibois Fourier-transform infrared (FTIR) synchrotron radiation (SR) microspectroscopy is a powerful molecular probe of biological samples at cellular resolution (<10,µm). As the brilliance of SR is 100,1000 times higher than that of a conventional Globar source, FTIR microscopes are now available in almost all advanced SR facilities around the world. However, in spite of this superior performance, the expected advances in IR SR microscopy have not yet been realised, particularly with regard to bio-analytical studies of single cells and soft tissues. In recent decades solid-state array detectors have revolutionized the fields of molecular spectroscopy and chemical imaging, and now new IR focal plane array detectors implemented at ultra-bright SR facilities will extend the performance and overcome the existing limitations, possibly allowing IR SR instrumentation to achieve the highest sensitivity and resolution of molecular imaging. The impact of IR imaging on large tissue area and the complexity of the analysis are discussed. In view of the high brilliance of SR sources, a comparison of published microscope images is given. Finally, it is briefly outlined how an optimized combination of IR instrumentation and SR optical systems could reach the expected advantages of a SR-based FTIR imaging system. [source] Determination of Sudan IV in hot chilli powder with luminol/dissolved oxygen chemiluminescence systemJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2010Lichuan Niu Abstract BACKGROUND: A green, simple and sensitive flow injection chemiluminescence (CL) procedure is proposed for the determination of Sudan dyes. The method is based on the finding that Sudan I, II, III and IV markedly enhance the CL intensity of the luminol/dissolved oxygen reaction. RESULTS: The increment in CL intensity was proportional to the concentration of Sudan I, II, III and IV, giving calibration graphs linear over the ranges 0.007,1, 0.5,30, 1,10 and 0.7,300 ng mL,1 respectively (R2 , 0.9981), with limits of detection of 0.002, 0.2, 0.3 and 0.2 ng mL,1 respectively. At a flow rate of 2 mL min,1, complete determination of Sudan dyes, including sampling and washing, could be accomplished in 40 s, with relative standard deviations of less than 5% (n = 7). CONCLUSION: The proposed method was successfully applied to the determination of Sudan IV in contaminated hot chilli powder, with recoveries ranging from 89.3 to 108.4%. The possible mechanism of enhancement of the lumininol/dissolved oxygen CL reaction by Sudan IV can be attributed to the acceleration of electron transfer. Compared with other procedures, the proposed CL method offers the highest sensitivity and the least reagent consumption for the determination of Sudan IV. Copyright © 2009 Society of Chemical Industry [source] Occult hepatitis B virus infection: a covert operationJOURNAL OF VIRAL HEPATITIS, Issue 1 2010F. B. Hollinger Summary., Detection of occult hepatitis B requires assays of the highest sensitivity and specificity with a lower limit of detection of less than 10 IU/mL for hepatitis B virus (HBV) DNA and <0.1 ng/mL for hepatitis B surface antigen (HBsAg). This covert condition is relatively common in patients with chronic hepatitis C virus (HCV) that seems to exert some influence on the replicative capacity and latency of HBV. Detection of virus-specific nucleic acid does not always translate into infectivity, and the occurrence of primer-generated HBV DNA that is of partial genomic length in immunocompetent individuals who have significant levels of hepatitis B surface antibody (anti-HBs) may not be biologically relevant. Acute flares of alanine aminotransferase (ALT) that occur during the early phase of therapy for HCV or ALT levels that remain elevated at the end of therapy in biochemical nonresponders should prompt an assessment for occult hepatitis B. Similarly, the plasma from patients with chronic hepatitis C that is hepatitis B core antibody (anti-HBc) positive (±anti-HBs at levels of <100 mIU/mL) should be examined for HBV DNA with the most sensitive assay available. If a liver biopsy is available, immunostaining for hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) should be contemplated and a portion of the sample tested for HBV DNA. This is another reason for optimal collection of a specimen (e.g. two passes with a 16-guage needle under ultrasound guidance). Transmission of HBV to immunosuppressed orthotopic liver transplant recipients by donors with occult hepatitis B (OHB) will continue to occupy the interests of the transplant hepatologist. As patients with OHB may have detectable HBV DNA in serum, peripheral blood mononuclear cells (PBMC) and/or liver that can be reactivated following immunosuppression or intensive cytotoxic chemotherapy, the patient needs to be either monitored or treated depending on the pretreatment serological results such as an isolated anti-HBc reaction or a detectable HBV DNA. [source] Performance comparison of slow-light coupled-resonator optical gyroscopesLASER & PHOTONICS REVIEWS, Issue 5 2009M. Terrel Abstract We investigate the connection between group velocity and rotation sensitivity in a number of resonant gyroscope designs. Two key comparisons are made. First, we compare two conventional sensors, namely a resonant fiber optic gyroscope (RFOG) and an interferometric fiber optic gyroscope (FOG). Second, we compare the RFOG to several recently proposed coupled-resonator optical waveguide (CROW) gyroscopes. We show that the relationship between loss and maximum rotation sensitivity is the same for both conventional and CROW gyroscopes. Thus, coupling multiple resonators together cannot enhance rotation sensitivity. While CROW gyroscopes offer the potential for large group indices, this increase of group index does not provide a corresponding increase in the maximum sensitivity to rotation. For a given footprint and a given total loss, the highest sensitivity is shown to be achieved either in a conventional RFOG utilizing a single resonator, or a conventional FOG. [source] Extended testing across, not within, tasks raises diagnostic accuracy of smell testing in Parkinson's disease,MOVEMENT DISORDERS, Issue 1 2009Sanne Boesveldt MSc Abstract The aim of this study was to determine whether extended olfactory testing within a single olfactory task and/or across olfactory tasks increases diagnostic accuracy of olfactory testing in Parkinson's disease (PD). Olfactory function was assessed using an extended version of the "Sniffin' Sticks", comprising 32-item odor identification and discrimination tasks, and a detection threshold task in 52 PD patients and 50 controls, all aged between 49 and 78 years. ROC curves based on sensitivity and specificity estimates were used to compare the diagnostic accuracy of extended and combined olfactory testing. There was no significant difference in diagnostic accuracy between the 16-item and the 32-item versions of the odor identification or discrimination test. The single olfactory test that was best in discriminating between PD patients and controls was a 16-item odor identification test. A combination of the 16-item identification test and the detection threshold task had a significantly higher area under the curve than the 16-item odor identification test alone. In conclusion, extended testing across, and not within, olfactory tasks increases diagnostic accuracy of olfactory testing in PD. A combination of an odor detection threshold task and a 16-item odor identification test had the highest sensitivity and specificity in distinguishing between PD patients and controls. © 2008 Movement Disorder Society [source] Predictive factors for organic central precocious puberty and utility of simplified gonadotropin-releasing hormone testsPEDIATRICS INTERNATIONAL, Issue 6 2007JIN-HO CHOI Abstract Background: The aim of the present study was to determine whether the clinical presentation of patients with central precocious puberty (CPP) permits differentiation between idiopathic and organic forms, and to examine whether luteinizing hormone (LH) determination in single blood sample after gonadotropin-releasing hormone (GnRH) administration is sufficient to diagnose CPP. Methods: Potential clinical and laboratory predictors for the presence of central nervous system (CNS) abnormalities were assessed. Sensitivities and specificities of LH and follicle-stimulating hormone (FSH) levels at 0, 15, 30, 60, 90 and 120 min were compared after GnRH stimulation. Results: In 45 girls with signs of breast development, 26 were diagnosed as having CPP. The age of onset in patients with organic CPP was 4.75 ± 2.01 years (range 1.2,7.1 years, median 5.0 years), whereas the age in patients with idiopathic CPP was 7.09 ± 0.87 years (range 5.0,7.9 years, median 7.0 years). This parameter is the only one showing statistical significance. In addition, the specimen at 30 min after GnRH stimulation yielded highest sensitivity for the diagnosis of CPP. Conclusions: The earlier the onset of disease, the higher the possibility of presence of CNS lesion. According to the mean GnRH-stimulated LH levels and sensitivity at each time, a single blood sample obtained for LH determined after GnRH administration at 30 min can be used to diagnose CPP. [source] Interleukin-1,, interleukin-6 and tumor necrosis factor-, levels in children with sepsis and meningitisPEDIATRICS INTERNATIONAL, Issue 2 2006NADIA M. FIDA Abstract Background: Cytokines are thought to be important endogenous mediators of the host immune response to infection. The purpose of the present study was to evaluate the utility of serum levels of interleukin (IL)-1,, IL-6 and tumor necrosis factor (TNF)-, in the prediction and differentiation of sepsis and meningitis in children. Methods: Blood was collected from 50 children admitted to hospital for suspicion of infection. On the basis of predetermined criteria and investigation, the children were classified into sepsis (n = 30) and meningitis (n = 20) groups, as well as into healthy controls (n = 24) and non-infected sick controls (n = 12). The sepsis group was subdivided according to culture results into S1 (proven sepsis, n = 11) and S2 (clinical sepsis, n = 19). Serum IL-1,, IL-6 and TNF-, were measured by enzyme-linked immunosorbent assay (ELISA) while C-reactive protein (CRP) was measured by nephelometer. Results: In non-infected sick controls, sepsis and meningitis groups, levels of CRP (P < 0.001, P < 0.05 and P < 0.01, respectively), IL-1, (P < 0.001 for all), and IL-6 (P < 0.01, P < 0.001, P < 0.001, respectively) were significantly elevated compared to healthy controls. In sepsis, levels of IL-1, increased in the S2 subgroup (P < 0.001) and IL-6 increased in the S1 and S2 subgroups (P < 0.05, P < 0.001, respectively) compared with healthy controls. In meningitis, IL-1, had the highest sensitivity and negative predictive value, while IL-6 had the highest specificity and positive predictive value in non-infected sick controls, sepsis and meningitis groups. Conclusion: Interleukin-1,, IL-6 and CRP are increased in non-infected sick controls, sepsis and meningitis patients but it is not possible to differentiate between them. IL-1, had the highest sensitivity in meningitis while IL-6 had the highest specificity in prediction of sepsis and meningitis and their assessment together may improve accuracy in the diagnosis of childhood infection. [source] Differential output of the high-sensitivity rod photoreceptor: AII amacrine pathwayTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 5 2008Artemis Petrides Abstract In the mammalian retina, the scotopic threshold of ganglion cells is in part dependent on how rod inputs are summed by their presynaptic cone bipolar cells. For ON cone bipolar cells, there are two anatomical routes for rod signals: 1) cone photoreceptors receive inputs via gap junctions with the surrounding, more numerous rods; and 2) ON cone bipolar cells receive highly convergent input via gap junctions with AII amacrine cells, which each receive input from hundreds of rods. Rod-cone coupling is thought to be utilized at higher photon fluxes relative to the AII-ON cone bipolar pathway due to the impedance mismatch of a single small rod driving a larger cone. Furthermore, it is widely held that the convergence of high-gain chemical synapses onto AIIs confers the highest sensitivity to ON cone bipolar cells and ganglion cells. A lack of coupling between one or more types of ON cone bipolar cells and AIIs would obviate this high-sensitivity pathway and explain the existence of ganglion cells with elevated scotopic thresholds. To investigate this possibility, we examined Neurobiotin and glycine diffusion from AIIs to bipolar cells and found that approximately one-fifth of ON cone bipolar cells are not coupled to AIIs. Unlike AII-AII coupling, which changes with ambient background intensity, the fraction of noncoupled ON cone bipolar cells was unaltered by dark or light adaptation. These data suggest that one of five morphologically distinct ON cone bipolar cell types is not coupled to AIIs and suggest that AII-ON cone bipolar coupling is modulated differently from AII-AII coupling. J. Comp. Neurol. 507:1653,1662, 2008. © 2008 Wiley-Liss, Inc. [source] TMPRSS2:ERG fusion transcripts in urine from prostate cancer patients correlate with a less favorable prognosisAPMIS, Issue 8 2009KARI ROSTAD Rostad K, Hellwinkel OJC, Haukaas SA, Halvorsen OJ, Øyan AM, Haese A, Budäus L, Albrecht H, Akslen LA, Schlomm T, Kalland K-H. TMPRSS2:ERG fusion transcripts in urine from prostate cancer patients correlate with a less favorable prognosis. APMIS 2009; 117: 575,82. The transcription factor ERG is highly upregulated in the majority of prostate cancers due to chromosomal fusion of the androgen responsive promoter of TMPRSS2 to the ERG reading frame. Our aim was to identify this gene fusion in urine samples from prostate cancer patients prior to radical treatment and to compare fusion status with clinicopathological variables. Urine fractions from 55 patients (with and without prior prostatic massage) were analyzed for the presence of TMPRSS2:ERG isoforms using real-time qPCR. Sixty-nine percent of urine samples following prostatic massage were positive for TMPRSS2:ERG isoforms a or b, five out of which were positive for both, vs 24% of samples obtained without prior massage. Isoform a seems to be most prevalent and some patients may be positive for more than one fusion variant, reflecting the multifocality of prostate cancer. Prostatic massage prior to sampling, analysis of pelleted urine material and detection of cDNA provided the highest sensitivity. Positive statistical correlations were identified between TMPRSS2:ERG fusion and high s-PSA, pathological stage and Gleason score. Our findings contribute to the increasing elucidation of the role of TMPRSS2:ERG in the development of prostate cancer. [source] Introital ultrasonography: a comparison of women with stress incontinence due to urethral hypermobility and continent womenBJU INTERNATIONAL, Issue 4 2006Jordi Cassadó OBJECTIVE To determine if there is a variable on introital ultrasonography (IUS) that can be used to distinguish between women with stress urinary incontinence (SUI) due to urethral hypermobility (UH) and continent women. PATIENTS AND METHODS This single-centre, prospective, blind, cohort, observational study comprised 383 women (245 continent and 138 incontinent) who were all appropriately informed volunteers selected according to the inclusion criteria. IUS with a convex probe was performed on all women; the measurement plane was standardized and coordinates were obtained at rest and on straining. Several distances were measured to determine if any provided an objective distinction between continent and incontinent women. RESULTS Among all the IUS variables assessed, sliding (calculated as the difference between the distance urethra-bladder neck, U-BN, at rest and under stress) was the best for distinguishing continent and incontinent women. The receiver operating characteristic curves showed that with a threshold of 8 mm, sliding had a sensitivity of 92% and a specificity of 79.6% for detecting SUI due to UH. The distances symphysis-urethra (S-U) and U-BN at rest could also discriminate, but with lower significance. CONCLUSIONS IUS is an important tool for diagnosing SUI; there are three independent variables, one dynamic (sliding) and two static (distances S-U and U-BN), that can be used to distinguish between continent women and those with SUI due to UH. Sliding is the most reliable, as it has the highest sensitivity and specificity. We think that the simplicity, low financial cost and reliability of IUS could allow it to be a routine procedure for physicians working in incontinence units. [source] Which color vision test should be used in progressive cone dystrophy?ACTA OPHTHALMOLOGICA, Issue 2007AAHJ THIADENS Purpose: The early manifestation of progressive cone dystrophy (COD) can remain unrecognized due to the relatively normal macular appearance. Color vision testing can be very useful as a first diagnostic step. The many available color vision tests have different benefits and shortcomings. We aimed to identify which test would be preferred to use in a clinical setting as a first step towards diagnosis of COD. Methods: We compared patients (n=18) derived from the ophthalmogenetic unit of Erasmus Medical Center and University Medical Center Nijmegen, with various levels of cone dysfunction. Golden Standard for diagnosis of COD was a diminished photopic ERG and a relative central scotoma on Goldmann perimetry. Controls (n=33) were patients from these clinics with other diagnoses or healthy companions of COD patients. We estimated sensitivity and specificity of the Ishihara test, Lanthony Desaturated and Saturated Panel D15 test, the Hardy-Rand-Rittler (HRR) pseudo-isochromatic plates, and the Nagel anomaloscope. We analyzed sensitivity, specificity and the predictive value with receiver operating characteristic curve (ROC). Results: The HRR test had the highest sensitivity and specificity for protan and deutan axes. HRR and Ishihara had the highest predictive value. Lanthony Panel D15 test did not have an additional predictive value for severe color vision defects. The Nagel anomaloscope was not reliable due to low specificity. Its results showed high variations among both healthy and afflicted individuals. Conclusions: The HRR test was the most useful for COD. This test had the highest sensitivity in detecting early dysfunction of all three cone types, and it adequately quantifies the level of cone dysfunction in the course of the disease. [source] Sensory and motor function of teeth and dental implants: A basis for osseoperceptionCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 1-2 2005Mats Trulsson SUMMARY 1.,When dental implants are loaded mechanically, a sensation, often referred to as osseoperception, is evoked. The sensory signals underlying this phenomenon are qualitatively different from the signals evoked when loading a natural tooth. In contrast with osseointegrated dental implants, natural teeth are equipped with periodontal mechanoreceptors that signal information about tooth loads. In the present review, the functional properties of human periodontal mechanoreceptors will be presented, along with a discussion about their likely functional role in the control of human jaw actions. 2.,Microneurographic experiments reveal that human periodontal mechanoreceptors adapt slowly to maintained tooth loads. Populations of periodontal receptors encode information about both which teeth are loaded and the direction of forces applied to individual teeth. 3.,Most receptors exhibit a markedly curved relationship between discharge rate and force amplitude, featuring the highest sensitivity to changes in tooth load at surprisingly low forces (below 1 N for anterior teeth and 4 N for posterior teeth). Accordingly, periodontal receptors efficiently encode tooth load when subjects first contact, hold and gently manipulate food by the teeth. In contrast, only a minority of receptors encodes the rapid and strong increase in force generated when biting through food. 4.,It is concluded that humans use periodontal afferent signals to control jaw actions associated with intra-oral manipulation of food rather than exertion of jaw power actions. Consequently, patients who lack information from periodontal receptors show an impaired fine motor control of the mandible. [source] | ||||||||||||||||