The influence of zero value subtraction on the performance of a new laser fluorescence device for approximal caries detection

The aim of this study was to assess the influence of the zero value subtraction on the performance of laser fluorescence (LFpen) for approximal caries detection. Three areas (cuspal, middle and cervical) of both mesial and distal buccal surfaces of 78 permanent molars were assessed using both wedge-shaped (WDG) and tapered wedge-shaped (TWDG) tips. With the addition of the average, one cut-off value for each area was obtained and the performance was assessed. The areas under the receiver operating characteristics (ROC) curve, specificity, sensitivity and accuracy with and without the zero value subtraction were calculated. The McNemar test revealed a statistically significant difference for specificity at thresholds D(1), D(2) and D(3) (WDG) and D(1) and D(2) (TWDG) when the zero value subtraction was not performed. Influence of the zero value subtraction on the LFpen performance was observed for approximal caries detection. However, when modified cut-off values were used, the zero value subtraction could be eliminated.

In vivo evaluation of laser fluorescence performance using different cut-off limits for occlusal caries detection

The aim of this in vivo study was to evaluate the performance of laser fluorescence (LF) comparing different cut-off limits for occlusal caries detection. One hundred and thirty first permanent molars were selected. Visual examination and LF assessments were performed independently. The extent of caries was assessed after operative intervention. New cut-off limits were established and compared with those proposed by the manufacturer and by Lussi et al. (Eur J Oral Sci 109:14-19, 2001). Similar sensitivity and higher specificity was found at D(2) (considering as disease only dentin caries) when the LF cut-off limits proposed by Lussi et al. and the new one were compared. At the D(3) threshold (considering as disease only deep dentin caries), no statistically significant difference among the cut-off limits for sensitivity was found. However, the new cut-off limits showed higher specificity. The LF device provided good ability to detect dentin caries lesions. Furthermore, the new cut-off limits and the values proposed by Lussi et al. could be suggested for the in vivo detection of occlusal caries.

Development and validation of GT3X accelerometer cut-off points in 5- to 9-year-old children based on indirect calorimetry measurements

The ActiGraph accelerometer is commonly used to measure physical activity in children. Count cut-off points are needed when using accelerometer data to determine the time a person spent in moderate or vigorous physical activity. For the GT3X accelerometer no cut-off points for young children have been published yet. The aim of the current study was thus to develop and validate count cut-off points for young children. Thirty-two children aged 5 to 9 years performed four locomotor and four play activities. Activity classification into the light-, moderate- or vigorous-intensity category was based on energy expenditure measurements with indirect calorimetry. Vertical axis as well as vector magnitude cut-off points were determined through receiver operating characteristic curve analyses with the data of two thirds of the study group and validated with the data of the remaining third. The vertical axis cut-off points were 133 counts per 5 sec for moderate to vigorous physical activity (MVPA), 193 counts for vigorous activity (VPA) corresponding to a metabolic threshold of 5 MET and 233 for VPA corresponding to 6 MET. The vector magnitude cut-off points were 246 counts per 5 sec for MVPA, 316 counts for VPA - 5 MET and 381 counts for VPA - 6 MET. When validated, the current cut-off points generally showed high recognition rates for each category, high sensitivity and specificity values and moderate agreement in terms of the Kappa statistic. These results were similar for vertical axis and vector magnitude cut-off points. The current cut-off points adequately reflect MVPA and VPA in young children. Cut-off points based on vector magnitude counts did not appear to reflect the intensity categories better than cut-off points based on vertical axis counts alone.

Evaluation of the diagnostic value of the ELISA tests developed by using EgHF, Em2 and EmII/3-10 antigens in the serological diagnosis of alveolar echinococcosis

Alveolar echinococcosis (AE), caused by larva stage of Echinococcus multilocularis, is one of the lethal parasitic diseases of man and a major public health problem in many countries in the northern hemisphere. When the living conditions and habits in Turkey were considered in terms of relation with the life cycle of the parasite, it was suggested that AE has been much more common than reported mainly from the Eastern Anatolia region of Turkey. Since in vitro serologic diagnosis tests with high specificity for AE have not been used in our country, most of the cases with liver lesions were misdiagnosed by radiological investigations as malignancies. The aim of this study was to evaluate the diagnostic value of the in-house ELISA methods developed by using three different antigens (EgHF, Em2, EmII/3-10) in the serological diagnosis of AE. The study samples included a total of 100 sera provided by Bern University Parasitology Institute where samples were obtained from patients with helminthiasis and all were confirmed by clinical, parasitological and/or histopathological means. Ten samples from each of the cases infected by E.multilocularis, E.granulosus, Taenia solium, Wuchereria bancrofti, Strongyloides stercolaris, Ascaris lumbricoides, Toxocara canis, Trichinella spiralis, Fasciola hepatica and Schistosoma haematobium were studied. In the study, EgHF (E.granulosus hydatid fluid) antigens were prepared in our laboratory from the liver cyst fluids of sheeps with cystic echinococcosis, however Em2 (E.multilocularis metacestode-purified laminated layer) and EmII/3-10 (E.multilocularis recombinant protoscolex tegument) antigens were provided by Bern University Parasitology Institute. Flat bottom ELISA plates were covered with EgHF, Em2 and EmII/3-10 antigens in the concentrations of 2.5 µg, 1 µg and 0.18 µg per well, respectively, and all sera were tested by EgHF-ELISA, Em2-ELISA and EmII/3-10-ELISA methods. For each tests, the samples which were reactive above the cut-off value (mean OD of negative controls+2 SD) were accepted as positive. The sensitivity of the ELISA tests performed with EgHF, Em2 and Em2II/3-10 antigens were estimated as 100%, 90% and 90%, respectively, whereas the specificity were 63%, 91% and 91%, respectively. When Em2-ELISA and EmII/3-10-ELISA tests were evaluated together, the specificity increased to 96%. Our data indicated that the highest sensitivity (100% with EgHF-ELISA) and specificity (96% with Em2-ELISA + EmII/3-10-ELISA) for the serodiagnosis of AE can be achieved by the combined use of the ELISA tests with three different antigens. It was concluded that the early and accurate diagnosis of AE in our country which is endemic for that disease, could be supported by the use of highly specific serological tests such as Em2-ELISA ve EmII/3-10-ELISA contributing radiological data.

Urine tested positive for ethyl glucuronide and ethyl sulphate after the consumption of "non-alcoholic" beer

In abstinence maintenance programs, for reissuing the driving licence and in workplace monitoring programs abstinence from ethanol and its proof are demanded. Various monitoring programs that mainly use ethyl glucuronide (EtG) as alcohol consumption marker have been established. To abstain from ethanol, but not from the taste of alcoholic beverages, in particular non-alcoholic beer has become more and more popular. In Germany, these "alcohol-free" beverages may still have an ethanol content of up to 0.5vol.% without the duty of declaration. Due to severe negative consequences resulting from positive EtG tests, a drinking experiment with 2.5L of non-alcoholic beer per person was performed to address the question of measurable concentrations of the direct metabolites EtG and EtS (ethyl sulphate) in urine and blood. Both alcohol consumption markers - determined by LC-MS/MS - were found in high concentrations: maximum concentrations in urine found in three volunteers were EtG 0.30-0.87mg/L and EtS 0.04-0.07mg/L, i.e., above the often applied cut-off value for the proof of abstinence of 0.1mg EtG/L. In the urine samples of one further volunteer, EtG and EtS concentrations cumulated over-night and reached up to 14.1mg/L EtG and 16.1mg/L EtS in the next morning's urine. Ethanol concentrations in blood and urine samples were negative (determined by HS-GC-FID and by an ADH-based method).

Association between variants of the leptin receptor gene (LEPR) and overweight: a systematic review and an analysis of the CoLaus study

Background Three non-synonymous single nucleotide polymorphisms (Q223R, K109R and K656N) of the leptin receptor gene (LEPR) have been tested for association with obesity-related outcomes in multiple studies, showing inconclusive results. We performed a systematic review and meta-analysis on the association of the three LEPR variants with BMI. In addition, we analysed 15 SNPs within the LEPR gene in the CoLaus study, assessing the interaction of the variants with sex. Methodology/Principal Findings We searched electronic databases, including population-based studies that investigated the association between LEPR variants Q223R, K109R and K656N and obesity- related phenotypes in healthy, unrelated subjects. We furthermore performed meta-analyses of the genotype and allele frequencies in case-control studies. Results were stratified by SNP and by potential effect modifiers. CoLaus data were analysed by logistic and linear regressions and tested for interaction with sex. The meta-analysis of published data did not show an overall association between any of the tested LEPR variants and overweight. However, the choice of a BMI cut-off value to distinguish cases from controls was crucial to explain heterogeneity in Q223R. Differences in allele frequencies across ethnic groups are compatible with natural selection of derived alleles in Q223R and K109R and of the ancient allele in K656N in Asians. In CoLaus, the rs10128072, rs3790438 and rs3790437 variants showed interaction with sex for their association with overweight, waist circumference and fat mass in linear regressions. Conclusions Our systematic review and analysis of primary data from the CoLaus study did not show an overall association between LEPR SNPs and overweight. Most studies were underpowered to detect small effect sizes. A potential effect modification by sex, population stratification, as well as the role of natural selection should be addressed in future genetic association studies.

Liver breath tests non-invasively predict higher stages of non-alcoholic steatohepatitis

Effectively assessing subtle hepatic metabolic functions by novel non-invasive tests might be of clinical utility in scoring NAFLD (non-alcoholic fatty liver disease) and in identifying altered metabolic pathways. The present study was conducted on 39 (20 lean and 19 obese) hypertransaminasemic patients with histologically proven NAFLD {ranging from simple steatosis to severe steatohepatitis [NASH (non-alcoholic steatohepatitis)] and fibrosis} and 28 (20 lean and eight overweight) healthy controls, who underwent stable isotope breath testing ([(13)C]methacetin and [(13)C]ketoisocaproate) for microsomal and mitochondrial liver function in relation to histology, serum hyaluronate, as a marker of liver fibrosis, and body size. Compared with healthy subjects and patients with simple steatosis, NASH patients had enhanced methacetin demethylation (P=0.001), but decreased (P=0.001) and delayed (P=0.006) ketoisocaproate decarboxylation, which was inversely related (P=0.001) to the degree of histological fibrosis (r=-0.701), serum hyaluronate (r=-0.644) and body size (r=-0.485). Ketoisocaproate decarboxylation was impaired further in obese patients with NASH, but not in patients with simple steatosis and in overweight controls. NASH and insulin resistance were independently associated with an abnormal ketoisocaproate breath test (P=0.001). The cut-off value of 9.6% cumulative expired (13)CO(2) for ketoisocaproate at 60 min was associated with the highest prediction (positive predictive value, 0.90; negative predictive value, 0.73) for NASH, yielding an overall sensitivity of 68% and specificity of 94%. In conclusion, both microsomal and mitochondrial functions are disturbed in NASH. Therefore stable isotope breath tests may usefully contribute to a better and non-invasive characterization of patients with NAFLD.

Novel pressure-to-cornea index in glaucoma

BACKGROUND: Several conversion tables and formulas have been suggested to correct applanation intraocular pressure (IOP) for central corneal thickness (CCT). CCT is also thought to represent an independent glaucoma risk factor. In an attempt to integrate IOP and CCT into a unified risk factor and avoid uncertain correction for tonometric inaccuracy, a new pressure-to-cornea index (PCI) is proposed. METHODS: PCI (IOP/CCT(3)) was defined as the ratio between untreated IOP and CCT(3) in mm (ultrasound pachymetry). PCI distribution in 220 normal controls, 53 patients with normal-tension glaucoma (NTG), 76 with ocular hypertension (OHT), and 89 with primary open-angle glaucoma (POAG) was investigated. PCI's ability to discriminate between glaucoma (NTG+POAG) and non-glaucoma (controls+OHT) was compared with that of three published formulae for correcting IOP for CCT. Receiver operating characteristic (ROC) curves were built. RESULTS: Mean PCI values were: Controls 92.0 (SD 24.8), NTG 129.1 (SD 25.8), OHT 134.0 (SD 26.5), POAG 173.6 (SD 40.9). To minimise IOP bias, eyes within the same 2 mm Hg range between 16 and 29 mm Hg (16-17, 18-19, etc) were separately compared: control and NTG eyes as well as OHT and POAG eyes differed significantly. PCI demonstrated a larger area under the ROC curve (AUC) and significantly higher sensitivity at fixed 80% and 90% specificities compared with each of the correction formulas; optimum PCI cut-off value 133.8. CONCLUSIONS: A PCI range of 120-140 is proposed as the upper limit of "normality", 120 being the cut-off value for eyes with untreated pressures or=22 mm Hg. PCI may reflect individual susceptibility to a given IOP level, and thus represent a glaucoma risk factor. Longitudinal studies are needed to prove its prognostic value.

Clinical presentation of celiac disease and the diagnostic accuracy of serologic markers in children

There has been growing recognition of a changing clinical presentation of celiac disease (CD), with the manifestation of milder symptoms. Serologic testing is widely used to screen patients with suspected CD and populations at risk. The aim of this retrospective analysis was to evaluate the clinical presentation of CD in childhood, assess the diagnostic value of serologic tests, and investigate the impact of IgA deficiency on diagnostic accuracy. We evaluated 206 consecutive children with suspected CD on the basis of clinical symptoms and positive serology results. Ninety-four (46%) had biopsy-proven CD. The median age at diagnosis of CD was 6.8 years; 15% of the children were <2 years of age. There was a higher incidence of CD in girls (p = 0.003). Iron deficiency and intestinal complaints were more frequent in children with CD than those without CD (61% vs. 33%, p = 0.0001 and 71% vs. 55%, p = 0.02, respectively), while failure to thrive was less common (35% vs. 53%, p = 0.02). The sensitivity of IgA tissue transglutaminase (IgA-tTG) was 0.98 when including all children and 1.00 after excluding children with selective IgA deficiency. The specificity of IgA-tTG was 0.73 using the recommended cut-off value of 20 IU, and this improved to 0.94 when using a higher cut-off value of 100 IU. All children with CD and relative IgA deficiency (IgA levels that are measurable but below the age reference [n = 8]) had elevated IgA-tTG. In conclusion, CD is frequently diagnosed in school-age children with relatively mild symptoms. The absence of intestinal symptoms does not preclude the diagnosis of CD; many children with CD do not report intestinal symptoms. While the sensitivity of IgA-tTG is excellent, its specificity is insufficient for the diagnostic confirmation of a disease requiring life-long dietary restrictions. Children with negative IgA-tTG and decreased but measurable IgA values are unlikely to have CD.

[Study protocol of the VISEP study. Response of the SepNet study group]

In the commentary by Zander et al. the authors appear concerned about the methods and results of our, at that time, unpublished sepsis trial evaluating hydroxyethyl starch (HES) and insulin therapy. Unfortunately, the authors' concerns are based on false assumptions about the design, conduct and modes of action of the compounds under investigation. For instance, in our study the HES solution was not used for maintenance of daily fluid requirements, so that the assumption of the authors that this colloid was used "exclusively" is wrong. Moreover, the manufacturer of Hemohes, the HES product we used, gives no cut-off value for creatinine, thus the assumption that this cut-off value was "doubled" in our study is also incorrect. Other claims by the authors such as that lactated solutions cause elevated lactate levels, iatrogenic hyperglycemia and increase O(2) consumption are unfounded. There is no randomized controlled trial supporting such a claim - this claim is neither consistent with our study data nor with any credible published sepsis guidelines or with routine practice worldwide. We fully support open scientific debate. Our study methods and results have now been published after a strict peer-reviewing process and this data is now open to critical and constructive reviewing. However, in our opinion this premature action based on wrong assumptions and containing comments by representatives of pharmaceutical companies does not contribute to a serious, unbiased scientific discourse.

CD69 upregulation on T cells as an in vitro marker for delayed-type drug hypersensitivity

BACKGROUND: T cells play a key role in delayed-type drug hypersensitivity reactions. Their reactivity can be assessed by their proliferation in response to the drug in the lymphocyte transformation test (LTT). However, the LTT imposes limitations in terms of practicability, and an alternative method that is easier to implement than the LTT would be desirable. METHODS: Four months to 12 years after acute drug hypersensitivity reactions, CD69 upregulation on T cells of 15 patients and five healthy controls was analyzed by flow cytometry. RESULTS: All 15 LTT-positive patients showed a significant increase of CD69 expression on T cells after 48 h of drug-stimulation exclusively with the drugs incriminated in drug-hypersensitivities. A stimulation index of 2 as cut-off value allowed discrimination between nonreactive and reactive T cells in LTT and CD69 upregulation. T cells (0.5-3%) showed CD69 up-regulation. The reactive cell population consisted of a minority of truly drug reactive T cells secreting cytokines and a higher number of bystander T cells activated by IL-2 and possibly other cytokines. CONCLUSIONS: CD69 upregulation was observed after 2 days in all patients with a positive LTT after 6 days, thus appearing to be a promising tool to identify drug-reactive T cells in the peripheral blood of patients with drug-hypersensitivity reactions.

Early troponin T and prediction of potentially correctable in-hospital complications after coronary artery bypass grafting surgery

BACKGROUND Peak levels of troponin T (TnT) reliably predict morbidity and mortality after cardiac surgery. However, the therapeutic window to manage CABG-related in-hospital complications may close before the peak is reached. We investigated whether early TnT levels correlate as well with complications after coronary artery bypass grafting (CABG) surgery. METHODS A 12 month consecutive series of patients undergoing elective isolated CABG procedures (mini-extra-corporeal circuit, Cardioplegic arrest) was analyzed. Logistic regression modeling was used to investigate whether TnT levels 6 to 8 hours after surgery were independently associated with in-hospital complications (either post-operative myocardial infarction, stroke, new-onset renal insufficiency, intensive care unit (ICU) readmission, prolonged ICU stay (>48 hours), prolonged need for vasopressors (>24 hours), resuscitation or death). RESULTS A total of 290 patients, including 36 patients with complications, was analyzed. Early TnT levels (odds ratio (OR): 6.8, 95% confidence interval (CI): 2.2-21.4, P=.001), logistic EuroSCORE (OR: 1.2, 95%CI: 1.0-1.3, P=.007) and the need for vasopressors during the first 6 postoperative hours (OR: 2.7, 95%CI: 1.0-7.1, P=.05) were independently associated with the risk of complications. With consideration of vasopressor use during the first 6 postoperative hours, the sum of specificity (0.958) and sensitivity (0.417) of TnT for subsequent complications was highest at a TnT cut-off value of 0.8 ng/mL. CONCLUSION Early TnT levels may be useful to guide ICU management of CABG patients. They predict clinically relevant complications within a potential therapeutic window, particularly in patients requiring vasopressors during the first postoperative hours, although with only moderate sensitivity.

Survey of bluetongue virus infection in free-ranging wild ruminants in Switzerland.

BACKGROUND In 2006, bluetongue virus serotype 8 (BTV-8) was detected for the first time in central Europe. Measures to control the infection in livestock were implemented in Switzerland but the question was raised whether free-ranging wildlife could be a maintenance host for BTV-8. Furthermore Toggenburg orbivirus (TOV), considered as a potential 25th BTV serotype, was detected in 2007 in domestic goats in Switzerland and wild ruminants were considered a potential source of infection. To assess prevalences of BTV-8 and TOV infections in wildlife, we conducted a serological and virological survey in red deer, roe deer, Alpine chamois and Alpine ibex between 2009 and 2011. Because samples originating from wildlife carcasses are often of poor quality, we also documented the influence of hemolysis on test results, and evaluated the usefulness of confirmatory tests. RESULTS Ten out of 1,898 animals (0.5%, 95% confidence interval 0.3-1.0%) had detectable antibodies against BTV-8 and BTV-8 RNA was found in two chamois and one roe deer (0.3%, 0.1-0.8%). Seroprevalence was highest among red deer, and the majority of positive wild animals were sampled close to areas where outbreaks had been reported in livestock. Most samples were hemolytic and the range of the optical density percentage values obtained in the screening test increased with increasing hemolysis. Confirmatory tests significantly increased specificity of the testing procedure and proved to be applicable even on poor quality samples. Nearly all samples confirmed as positive had an optical density percentage value greater than 50% in the ELISA screening. CONCLUSIONS Prevalence of BTV-8 infection was low, and none of the tested animals were positive for TOV. Currently, wild ruminants are apparently not a reservoir for these viruses in Switzerland. However, we report for the first time BTV-8 RNA in Alpine chamois. This animal was found at high altitude and far from a domestic outbreak, which suggests that the virus could spread into/through the Alps. Regarding testing procedures, hemolysis did not significantly affect test results but confirmatory tests proved to be necessary to obtain reliable prevalence estimates. The cut-off value recommended by the manufacturer for the screening test was applicable for wildlife samples.