Performance of fluorescence-based and conventional methods of occlusal caries detection in primary molars - an in vitro study

International Journal of Paediatric Dentistry 2012; 22: 459466 Aim. This in vitro study aimed to test the performance of fluorescence-based methods in detecting occlusal caries lesions in primary molars compared to conventional methods. Design. Two examiners assessed 113 sites on 77 occlusal surfaces of primary molars using three fluorescence devices: DIAGNOdent (LF), DIAGNOdent pen (LFpen), and fluorescence camera (VistaProof-FC). Visual inspection (ICDAS) and radiographic methods were also evaluated. One examiner repeated the evaluations after one month. As reference standard method, the lesion depth was determined after sectioning and evaluation in stereomicroscope. The area under the ROC curve (Az), sensitivity, specificity, and accuracy of the methods were calculated at enamel (D1) and dentine caries (D3) lesions thresholds. The intra and interexaminer reproducibility were calculated using the intraclass correlation coefficient (ICC) and kappa statistics. Results. At D1, visual inspection presented higher sensitivities (0.970.99) but lower specificities (0.180.25). At D3, all the methods demonstrated similar performance (Az values around 0.90). Visual and radiographic methods showed a slightly higher specificity (values higher than 0.96) than the fluorescence based ones (values around 0.88). In general, all methods presented high reproducibility (ICC higher than 0.79). Conclusions. Although fluorescence-based and conventional methods present similar performance in detecting occlusal caries lesions in primary teeth, visual inspection alone seems to be sufficient to be used in clinical practice.

Propensity score matching approach to test the association of income inequality and mortality in Sao Paulo, Brazil

Background Support for the adverse effect of high income inequality on population health has come from studies that focus on larger areas, such as the US states, while studies at smaller geographical areas (eg, neighbourhoods) have found mixed results. Methods We used propensity score matching to examine the relationship between income inequality and mortality rates across 96 neighbourhoods (distritos) of the municipality of Sao Paulo, Brazil. Results Prior to matching, higher income inequality distritos (Gini >= 0.25) had slightly lower overall mortality rates (2.23 per 10 000, 95% CI -23.92 to 19.46) compared to lower income inequality areas (Gini <0.25). After propensity score matching, higher inequality was associated with a statistically significant higher mortality rate (41.58 per 10 000, 95% CI 8.85 to 73.3). Conclusion In Sao Paulo, the more egalitarian communities are among some of the poorest, with the worst health profiles. Propensity score matching was used to avoid inappropriate comparisons between the health status of unequal (but wealthy) neighbourhoods versus equal (but poor) neighbourhoods. Our methods suggest that, with proper accounting of heterogeneity between areas, income inequality is associated with worse population health in Sao Paulo.

Infliximab partially impairs the anti-Mycobacterium tuberculosis immune responses of severe psoriasis patients with positive tuberculin skin-test

Background Infliximab and etarnecept are now widely used for treating severe psoriasis. However, these drugs, especially infliximab, increased the risk of tuberculosis reactivation. Surprisingly, epidemiological data suggest that the tuberculosis rate in patients taking infliximab in Sao Paulo State, Brazil, is similar to that of some developed, non-endemic countries. Objective The aim of this study was to better understand the effect of infliximab on Mycobacterium tuberculosis (Mtb) immune responses of psoriasis patients in an endemic setting (Brazil). Methods We evaluated the tuberculosis-specific immune responses of severe psoriasis patients and healthy individuals, both tuberculin skin test (TST) positive, in the presence/absence of infliximab. Patients had untreated severe psoriasis, no co-morbidities affecting the immune responses and a TST >10 mm. Healthy TST+ (>10 mm) individuals were evaluated in parallel. PBMC cultures from both groups were stimulated with different Mycobacterium tuberculosis (Mtb) antigens (ESAT-6, 85B and Mtb lysate) and phytohemagglutinin, with or without infliximab (5 mu g/mL). Parameters evaluated were TNF-alpha, IFN-gamma and IL-10 secretion by ELISA, overnight IFN-gamma ELISpot and lymphocyte proliferative response (LPR). Results Infliximab almost abolished TNF-alpha detection in PBMC supernatants of both groups. It also significantly reduced the LPR to phytohemagglutinin and the Mtb antigens as well as the IFN-gamma levels secreted into day 5 supernatants in both groups. There was no concomitant exaggerated IL-10 secretion that could account for the decreases in these responses. ELISpot showed that, contrasting with the central-memory responses above, infliximab did not affect effector-memory INF-gamma-releasing T-cell numbers. Conclusions Infliximab affected some, but not all aspects of the in vitro antituberculosis immune responses tested. The preserved effector-memory responses, putatively related to exposure to environmental mycobacteria, may help to explain the lower than expected susceptibility to tuberculosis reactivation in our setting. Received: 29 December 2010; Accepted: 9 March 2011

Effect of continuous and interval exercise training on the PETCO2 response during a graded exercise test in patients with coronary artery disease

OBJECTIVE: The purpose of this study was to evaluate the following: 1) the effects of continuous exercise training and interval exercise training on the end-tidal carbon dioxide pressure (PETCO2) response during a graded exercise test in patients with coronary artery disease; and 2) the effects of exercise training modalities on the association between PETCO2 at the ventilatory anaerobic threshold (VAT) and indicators of ventilatory efficiency and cardiorespiratory fitness in patients with coronary artery disease. METHODS: Thirty-seven patients (59.7 +/- 1.7 years) with coronary artery disease were randomly divided into two groups: continuous exercise training (n = 20) and interval exercise training (n = 17). All patients performed a graded exercise test with respiratory gas analysis before and after three months of the exercise training program to determine the VAT, respiratory compensation point (RCP) and peak oxygen consumption. RESULTS: After the interventions, both groups exhibited increased cardiorespiratory fitness. Indeed, the continuous exercise and interval exercise training groups demonstrated increases in both ventilatory efficiency and PETCO2 values at VAT, RCP, and peak of exercise. Significant associations were observed in both groups: 1) continuous exercise training (PETCO(2)VAT and cardiorespiratory fitness r = 0.49; PETCO(2)VAT and ventilatory efficiency r = -0.80) and 2) interval exercise training (PETCO(2)VAT and cardiorespiratory fitness r = 0.39; PETCO(2)VAT and ventilatory efficiency r = -0.45). CONCLUSIONS: Both exercise training modalities showed similar increases in PETCO2 levels during a graded exercise test in patients with coronary artery disease, which may be associated with an improvement in ventilatory efficiency and cardiorespiratory fitness.

MODEL PARTITIONS AND COMPACT TEST CASE SUITES

We present a generalized test case generation method, called the G method. Although inspired by the W method, the G method, in contrast, allows for test case suite generation even in the absence of characterization sets for the specification models. Instead, the G method relies on knowledge about the index of certain equivalences induced at the implementation models. We show that the W method can be derived from the G method as a particular case. Moreover, we discuss some naturally occurring infinite classes of FSM models over which the G method generates test suites that are exponentially more compact than those produced by the W method.

Six minute walk test Z score: Correlations with cystic fibrosis severity markers

Background: The six-minute-walk-test (6MWT) has been increasingly used in cystic fibrosis (CF) patients. However, few studies in children have correlated 6MWT with current parameters used to evaluate CF severity. Moreover, no study transformed the values of distance walked from meters into Z scores to avoid bias like age and gender, which are sources of 6MWT variability. Methods: A cross-sectional descriptive study was performed to analyze the correlations (Spearman) among forced expiratory volume in one second (FEV1), body mass index (BMI), chest radiography (CXR), chest tomography (CT), and 6MWT Z score (Z-6MWT). Clinically stable CF patients, aged 6-21 years, were included. Results: 34 patients, 14F/20M, mean age 12.1 +/- 4.0 years were studied. The mean Z-6MWT was -1.1 +/- 1.106. The following correlations versus Z-6MWT were found: FEV1 (r=0.59, r(2)=0.32, p=0.0002), BMI Z score (r=0.42, r(2)=0.17, p=0.013), CXR (r=0.34, r(2)=0.15, p=0.0472) and CT (r=-0.45, r(2)=0.23, p=0.0073). Conclusions: In conclusion there was a significant, but poor, correlation between the six minute walk test Z score and the cystic fibrosis severity markers currently in use. (C) 2011 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Performance characteristics of Pap test, VIA, VILI, HR-HPV testing, cervicography, and colposcopy in diagnosis of significant cervical pathology

We sought to evaluate the performance of diagnostic tools to establish an affordable setting for early detection of cervical cancer in developing countries. We compared the performance of different screening tests and their feasibility in a cohort of over 12,000 women: conventional Pap smear, liquid-based cytology, visual inspection with acetic acid (VIA), visual inspection with Iodine solution (VILI), cervicography, screening colposcopy, and high-risk human papillomavirus (HPV) testing (HR-HPV) collected by physician and by self-sampling. HR-HPV assay collected by the physician has the highest sensitivity (80 %), but high unnecessary referrals to colposcopy (15.1 %). HR-HPV test in self-sampling had a markedly lower (57.1 %) sensitivity. VIA, VILI, and cervicography had a poor sensitivity (47.4, 55, and 28.6 %, respectively). Colposcopy presented with sensitivity of 100 % in detecting CIN2+, but the lowest specificity (66.9 %). Co-testing with VIA and VILI Pap test increased the sensitivity of stand-alone Pap test from 71.6 to 87.1 % and 71.6 to 95 %, respectively, but with high number of unnecessary colposcopies. Co-testing with HR-HPV importantly increased the sensitivity of Pap test (to 86 %), but with high number of unnecessary colposcopies (17.5 %). Molecular tests adjunct to Pap test seems a realistic option to improve the detection of high-grade lesions in population-based screening programs.

Human eosinophil adhesion and degranulation stimulated with eotaxin and RANTES in vitro: Lack of interaction with nitric oxide

Abstract Background Airway eosinophilia is considered a central event in the pathogenesis of asthma. The toxic components of eosinophils are thought to be important in inducing bronchial mucosal injury and dysfunction. Previous studies have suggested an interaction between nitric oxide (NO) and chemokines in modulating eosinophil functions, but this is still conflicting. In the present study, we have carried out functional assays (adhesion and degranulation) and flow cytometry analysis of adhesion molecules (VLA-4 and Mac-1 expression) to evaluate the interactions between NO and CC-chemokines (eotaxin and RANTES) in human eosinophils. Methods Eosinophils were purified using a percoll gradient followed by immunomagnetic cell separator. Cell adhesion and degranulation were evaluated by measuring eosinophil peroxidase (EPO) activity, whereas expression of Mac-1 and VLA-4 was detected using flow cytometry. Results At 4 h incubation, both eotaxin (100 ng/ml) and RANTES (1000 ng/ml) increased by 133% and 131% eosinophil adhesion, respectively. L-NAME alone (but not D-NAME) also increased the eosinophil adhesion, but the co-incubation of L-NAME with eotaxin or RANTES did not further affect the increased adhesion seen with chemokines alone. In addition, L-NAME alone (but not D-NAME) caused a significant cell degranulation, but it did not affect the CC-chemokine-induced cell degranulation. Incubation of eosinophils with eotaxin or RANTES, in absence or presence of L-NAME, did not affect the expression of VLA-4 and Mac-1 on eosinophil surface. Eotaxin and RANTES (100 ng/ml each) also failed to elevate the cyclic GMP levels above baseline in human eosinophils. Conclusion Eotaxin and RANTES increase the eosinophil adhesion to fibronectin-coated plates and promote cell degranulation by NO-independent mechanisms. The failure of CC-chemokines to affect VLA-4 and Mac-1 expression suggests that changes in integrin function (avidity or affinity) are rather involved in the enhanced adhesion.

Effects of EDTA and Sodium Citrate on hormone measurements by fluorometric (FIA) and immunofluorometric (IFMA) methods

Abstract Background Measurements of hormonal concentrations by immunoassays using fluorescent tracer substance (Eu3+) are susceptible to the action of chemical agents that may cause alterations in its original structure. Our goal was to verify the effect of two types of anticoagulants in the hormone assays performed by fluorometric (FIA) or immunofluorometric (IFMA) methods. Methods Blood samples were obtained from 30 outpatients and were drawn in EDTA, sodium citrate, and serum separation Vacutainer®Blood Collection Tubes. Samples were analyzed in automatized equipment AutoDelfia™ (Perkin Elmer Brazil, Wallac, Finland) for the following hormones: Luteinizing hormone (LH), Follicle stimulating homone (FSH), prolactin (PRL), growth hormone (GH), Sex hormone binding globulin (SHBG), thyroid stimulating hormone (TSH), insulin, C peptide, total T3, total T4, free T4, estradiol, progesterone, testosterone, and cortisol. Statistical analysis was carried out by Kruskal-Wallis method and Dunn's test. Results No significant differences were seen between samples for LH, FSH, PRL and free T4. Results from GH, TSH, insulin, C peptide, SHBG, total T3, total T4, estradiol, testosterone, cortisol, and progesterone were significant different between serum and EDTA-treated samples groups. Differences were also identified between serum and sodium citrate-treated samples in the analysis for TSH, insulin, total T3, estradiol, testosterone and progesterone. Conclusions We conclude that the hormonal analysis carried through by FIA or IFMA are susceptible to the effects of anticoagulants in the biological material collected that vary depending on the type of assay.

Maximal exercise test is a useful method for physical capacity and oxygen consumption determination in streptozotocin-diabetic rats

Abstract Background The aim of the present study was to investigate the relationship between speed during maximum exercise test (ET) and oxygen consumption (VO2) in control and STZ-diabetic rats, in order to provide a useful method to determine exercise capacity and prescription in researches involving STZ-diabetic rats. Methods Male Wistar rats were divided into two groups: control (CG, n = 10) and diabetic (DG, n = 8). The animals were submitted to ET on treadmill with simultaneous gas analysis through open respirometry system. ET and VO2 were assessed 60 days after diabetes induction (STZ, 50 mg/Kg). Results VO2 maximum was reduced in STZ-diabetic rats (72.5 ± 1 mL/Kg/min-1) compared to CG rats (81.1 ± 1 mL/Kg/min-1). There were positive correlations between ET speed and VO2 (r = 0.87 for CG and r = 0.8 for DG), as well as between ET speed and VO2 reserve (r = 0.77 for CG and r = 0.7 for DG). Positive correlations were also obtained between measured VO2 and VO2 predicted values (r = 0.81 for CG and r = 0.75 for DG) by linear regression equations to CG (VO2 = 1.54 * ET speed + 52.34) and DG (VO2 = 1.16 * ET speed + 51.99). Moreover, we observed that 60% of ET speed corresponded to 72 and 75% of VO2 reserve for CG and DG, respectively. The maximum ET speed was also correlated with VO2 maximum for both groups (CG: r = 0.7 and DG: r = 0.7). Conclusion These results suggest that: a) VO2 and VO2 reserve can be estimated using linear regression equations obtained from correlations with ET speed for each studied group; b) exercise training can be prescribed based on ET in control and diabetic-STZ rats; c) physical capacity can be determined by ET. Therefore, ET, which involves a relatively simple methodology and low cost, can be used as an indicator of cardio-respiratory capacity in future studies that investigate the physiological effect of acute or chronic exercise in control and STZ-diabetic male rats.

Towards a precise test for malaria diagnosis in the Brazilian Amazon: comparison among field microscopy, a rapid diagnostic test, nested PCR, and a computational expert system based on artificial neural networks

Abstract Background Accurate malaria diagnosis is mandatory for the treatment and management of severe cases. Moreover, individuals with asymptomatic malaria are not usually screened by health care facilities, which further complicates disease control efforts. The present study compared the performances of a malaria rapid diagnosis test (RDT), the thick blood smear method and nested PCR for the diagnosis of symptomatic malaria in the Brazilian Amazon. In addition, an innovative computational approach was tested for the diagnosis of asymptomatic malaria. Methods The study was divided in two parts. For the first part, passive case detection was performed in 311 individuals with malaria-related symptoms from a recently urbanized community in the Brazilian Amazon. A cross-sectional investigation compared the diagnostic performance of the RDT Optimal-IT, nested PCR and light microscopy. The second part of the study involved active case detection of asymptomatic malaria in 380 individuals from riverine communities in Rondônia, Brazil. The performances of microscopy, nested PCR and an expert computational system based on artificial neural networks (MalDANN) using epidemiological data were compared. Results Nested PCR was shown to be the gold standard for diagnosis of both symptomatic and asymptomatic malaria because it detected the major number of cases and presented the maximum specificity. Surprisingly, the RDT was superior to microscopy in the diagnosis of cases with low parasitaemia. Nevertheless, RDT could not discriminate the Plasmodium species in 12 cases of mixed infections (Plasmodium vivax + Plasmodium falciparum). Moreover, the microscopy presented low performance in the detection of asymptomatic cases (61.25% of correct diagnoses). The MalDANN system using epidemiological data was worse that the light microscopy (56% of correct diagnoses). However, when information regarding plasma levels of interleukin-10 and interferon-gamma were inputted, the MalDANN performance sensibly increased (80% correct diagnoses). Conclusions An RDT for malaria diagnosis may find a promising use in the Brazilian Amazon integrating a rational diagnostic approach. Despite the low performance of the MalDANN test using solely epidemiological data, an approach based on neural networks may be feasible in cases where simpler methods for discriminating individuals below and above threshold cytokine levels are available.

Inhibition of the NMDA receptor/Nitric Oxide pathway in the dorsolateral periaqueductal gray causes anxiolytic-like effects in rats submitted to the Vogel conflict test

Abstract Background Several studies had demonstrated the involvement of the dorsolateral portion of periaqueductal grey matter (dlPAG) in defensive responses. This region contains a significant number of neurons containing the enzyme nitric oxide synthase (NOS) and previous studies showed that non-selective NOS inhibition or glutamate NMDA-receptor antagonism in the dlPAG caused anxiolytic-like effects in the elevated plus maze. Methods In the present study we verified if the NMDA/NO pathway in the dlPAG would also involve in the behavioral suppression observed in rats submitted to the Vogel conflict test. In addition, the involvement of this pathway was investigated by using a selective nNOS inhibitor, Nω-propyl-L-arginine (N-Propyl, 0.08 nmol/200 nL), a NO scavenger, carboxy-PTIO (c-PTIO, 2 nmol/200 nL) and a specific NMDA receptor antagonist, LY235959 (4 nmol/200 nL). Results Intra-dlPAG microinjection of these drugs increased the number of punished licks without changing the number of unpunished licks or nociceptive threshold, as measure by the tail flick test. Conclusion The results indicate that activation of NMDA receptors and increased production of NO in the dlPAG are involved in the anxiety behavior displayed by rats in the VCT.

Observational study on efficacy of negative expiratory pressure test proposed as screening for obstructive sleep apnea syndrome among commercial interstate bus drivers - protocol study

Abstract Background Obstructive sleep apnea (OSA) is a respiratory disease characterized by the collapse of the extrathoracic airway and has important social implications related to accidents and cardiovascular risk. The main objective of the present study was to investigate whether the drop in expiratory flow and the volume expired in 0.2 s during the application of negative expiratory pressure (NEP) are associated with the presence and severity of OSA in a population of professional interstate bus drivers who travel medium and long distances. Methods/Design An observational, analytic study will be carried out involving adult male subjects of an interstate bus company. Those who agree to participate will undergo a detailed patient history, physical examination involving determination of blood pressure, anthropometric data, circumference measurements (hips, waist and neck), tonsils and Mallampati index. Moreover, specific questionnaires addressing sleep apnea and excessive daytime sleepiness will be administered. Data acquisition will be completely anonymous. Following the medical examination, the participants will perform a spirometry, NEP test and standard overnight polysomnography. The NEP test is performed through the administration of negative pressure at the mouth during expiration. This is a practical test performed while awake and requires little cooperation from the subject. In the absence of expiratory flow limitation, the increase in the pressure gradient between the alveoli and open upper airway caused by NEP results in an increase in expiratory flow. Discussion Despite the abundance of scientific evidence, OSA is still underdiagnosed in the general population. In addition, diagnostic procedures are expensive, and predictive criteria are still unsatisfactory. Because increased upper airway collapsibility is one of the main determinants of OSA, the response to the application of NEP could be a predictor of this disorder. With the enrollment of this study protocol, the expectation is to encounter predictive NEP values for different degrees of OSA in order to contribute toward an early diagnosis of this condition and reduce its impact and complications among commercial interstate bus drivers.

Impact of the rapid antigen detection test in diagnosis and treatment of acute pharyngotonsillitis in a Pediatric emergency room

OBJECTIVE: To evaluate the impact of the routine use of rapid antigen detection test in the diagnosis and treatment of acute pharyngotonsillitis in children. METHODS: This is a prospective and observational study, with a protocol compliance design established at the Emergency Unit of the University Hospital of Universidade de São Paulo for the care of children and adolescents diagnosed with acute pharyngitis. RESULTS: 650 children and adolescents were enrolled. Based on clinical findings, antibiotics would be prescribed for 389 patients (59.8%); using the rapid antigen detection test, they were prescribed for 286 patients (44.0%). Among the 261 children who would not have received antibiotics based on the clinical evaluation, 111 (42.5%) had positive rapid antigen detection test. The diagnosis based only on clinical evaluation showed 61.1% sensitivity, 47.7% specificity, 44.9% positive predictive value, and 57.5% negative predictive value. CONCLUSIONS: The clinical diagnosis of streptococcal pharyngotonsillitis had low sensitivity and specificity. The routine use of rapid antigen detection test led to the reduction of antibiotic use and the identification of a risk group for complications of streptococcal infection, since 42.5% positive rapid antigen detection test patients would not have received antibiotics based only on clinical diagnosis.