Granger causality (GC) is a very popular tool for assessing the presence of directional interactions between two time series of a multivariate data set. In its original formulation, GC does not ...account for zero-lag correlations possibly existing between the observed time series. In the present study we compare the GC with a novel measure, termed extended GC (eGC), able to capture instantaneous causal relationships. We present a two-step procedure for the practical estimation of eGC based on first detecting the existence of zero-lag correlations, and then assigning them to one of the two possible causal directions using pairwise measures of non-Gaussianity. The proposed method was validated in a simulation study, showing that the estimation procedure based on the extended representation overcomes the limits of the classic computation of GC, correctly detecting the presence and direction of zero-lag interactions and providing a meaningful causal interpretation based on the eGC. Then, GC and eGC were computed on the physiological variability series of heart period (HP), mean arterial pressure (AP) and cerebral blood flow velocity (FV) in ten subjects with postural related syncope (PRS), during different epochs of an head-up tilt test protocol. We found that both measures reflect the baroreflex impairment and the loss of cerebral autoregulation during pre-syncope. Furthermore, eGC analysis suggests that fast, within-beat effects between AP and FV variability contribute substantially to the mutual regulation of these physiological variables, and may play an important role in the impairment of cerebrovascular regulation associated with PRS.
The aim of the study was to evaluate the cytotoxicity of different glycolic acid concentrations (GA) and its effects on dentinal microhardness. Cytotoxicity was evaluated after inoculation of test ...irrigants in the lymphocyte primary culture for 3 min. The tested substances were distilled water(DW); 17% EDTA; QMix; 10% GA; 17% GA; and 25% GA. Counting of total, live and dead cells was performed, obtaining the average percentage of dead cells of each group. For microhardness evaluation, 60 root dentin samples were divided into the same tested groups (n = 10) and immersed in test irrigants for 3 min. Dentin microhardness was evaluated by Vicker test. Specific statistical analysis was made in both tests. Results showed significant lower cytotoxicity for QMix and 10% GA (P < 0.05). Moreover, all test irrigants presented similar values of microhardness than the control group (P > 0.05). In conclusion, lower GA concentration can be an alternative for final irrigation on endodontics.
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CMK, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Amphetamine-like drugs are sympathomimetic agents with marked central and peripheral stimulant properties. Despite the street illegal drugs such as amphetamine and ecstasy, some amphetamine-like ...compounds are also legally marketed under medical prescription in the treatment of attention deficit-hyperactivity disorder (methylphenidate) and obesity/overweight (fenproporex and diethylpropione). However, similar with what happens with their illicit analogues, therapeutic amphetamine-like drugs also share important toxicological risks. Although methylphenidate is considered the first choice in the treatment of attention deficit-hyperactivity disorder, its high popularity among teenagers and children is raising concern in the medical community. Regarding weight-loss purposes, the use of amphetamine-like compounds are very controversial, though. Thus, the present review will address pharmacokinetic, pharmacodynamic, and toxicological aspects of amphetamine-like compounds used with therapeutic aims.
To mitigate variability effects, this work explores decoupling cells on different adder topologies using a 7nm FinFET technology. Process variability shows an impact of up to 20% on nominal voltage ...and superior to 50% at near-threshold operation. After the insertion of DCells on the evaluated full adders, the circuits operating at nominal voltage present an increase of up to 20% on the robustness to delay variability and 40% on power consumption variability, with less than 20% of penalty in power and delay. Moreover, this technique adoption has a high impact on the results of circuits operating at near-threshold voltage; in some cases, reaching more than 40% reduction in performance for a small reduction in variability.
White matter lesions (WMLs) are commonly found on brain MRI of migraine patients. Migraine with aura (MA+) is associated with an increased frequency of right-to-left shunt (RLS) mostly due to patent ...foramen ovale. The relationship between WML load and RLS in MA+ is currently unknown.
MA+ patients were consecutively enrolled as part of the Shunt Associated Migraine (SAM) study. Patients underwent a standardized headache and vascular risk factors questionnaire, contrast-enhanced transcranial Doppler, blood coagulation tests, and brain MRI. RLS was categorized into four grades: no shunt, <10 microbubbles (mb), >10 mb single spikes pattern, and >10 mb shower/curtain pattern. Standard and fluid-attenuated inversion recovery T2-weighted MRI sequences were inspected for WMLs by three independent raters blinded to RLS grade. WML load was scored in the periventricular areas (PV-WMLs) with the Fazekas scale and in the deep white matter (D-WMLs) with the Scheltens scale. Interobserver agreement was good to excellent (kappa = 0.64 to 0.96, p < 0.0001). WML load was then correlated between patients with and without RLS.
One hundred eighty-five patients (77% women) were included. PV-WML load was similar between patients with and without RLS. D-WML load decreased in patients with RLS (p = 0.045). On logistic regression analysis, only age was associated with WMLs (p < 0.001).
The presence of right-to-left shunt does not increase white matter lesion load in patients who have migraine with aura.
Objective: The objective of the study was to compare the cerebral distribution of white matter lesions (WMLs) between migraine patients with different aura symptoms.
Methods: Migraine with aura (MA) ...patients were consecutively enrolled as part of the Shunt-Associated Migraine (SAM) study. According to clinical symptoms, aura was classified as motor, aphasic, sensory, visual or vertebrobasilar. Standard and FLAIR (fluid attenuated inversion recovery) T2-weighted MRI sequences were inspected for WMLs by three independent raters blinded to clinical data. WMLs were assessed in the periventricular areas (PV-WMLs) with the Fazekas scale and in the deep white matter (D-WMLs) with the Schelten's scale. Interobserver agreement was good to excellent (k = 0.64 to 0.96, p < .0001).
Results: One hundred and eighty-five patients (77% women) were included. Aura symptoms were classified as visual in 172 (99%) patients, sensory in 76 (42%), aphasic in 54 (30%), motor in 39 (21%) and vertebrobasilar in 17 (9%) patients. One hundred and four patients (57%) exhibited more than one type of aura. D-WMLs were mainly detected in the frontal lobes (86%). There was no association between type of aura and the presence of WMLs in any cerebral location.
Conclusion: Aura symptoms do not influence the cerebral distribution of WMLs associated with migraine disease.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The expansion of agricultural activities causes habitat loss and fragmentation and the pollution of natural ecosystems through the intense use of pesticides, which may affect the populations of ...amphibian anurans that inhabit agricultural areas. The present study evaluated the in situ bioaccumulation of pesticides in a population of
Leptodactylus luctator
that occupies farmland in southern Brazil. We also compared the genotoxicity of
L. luctator
populations from farmland and forested areas in the same region. We analyzed the micronuclei and nuclear abnormalities of 34 adult anurans, 19 from farmland, and 15 from the forested area. We also assessed the presence of 32 pesticides in liver samples obtained from 18 farmland-dwelling anurans, using chromatographic analysis. We recorded significantly higher rates of nuclear abnormalities in the individuals from the farmland, in comparison with the forest. We detected nine pesticides in the liver samples, of which, deltamethrin was the most common and carbosulfan was recorded at the highest concentrations. The bioaccumulation of pesticides and the higher levels of genotoxic damage found in the anurans from agricultural areas, as observed in the present study, represent a major potential problem for the conservation of these vertebrates, including the decline of their populations and the extinction of species.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Objectives. To evaluate, in patients with ulnar neuropathy at the elbow (UNE), if ultrasonographic differences in ulnar nerve size correlate with severity score determined by electrodiagnostic ...studies. Methods. We examined prospectively 38 patients (50 elbows) with UNE. Patients were classified into mild, moderate and severe groups according to electrodiagnostic studies. Cross-sectional areas (CSAs) of the ulnar nerve were measured 4 cm proximal to the medial epicondyle (CSA-prox), 4 cm distal to the epicondyle (CSA-dist) and at the maximum CSA (CSA-max) of the ulnar nerve found between these points. We used a control group of 50 normal elbows. Results. The CSA-max in the patient group was highly correlated with the severity score obtained by electrodiagnostic studies: mild: 11.1 ± 3.4 mm2, moderate: 15.8 ± 3.8 mm2, severe: 18.3 ± 5.1 mm2 (P < 0.001). Patients with UNE had larger ulnar nerve CSAs than controls at all three levels (P = 0.012 for CSA-prox, P < 0.001 for CSA-max, P = 0.003 for CSA-dist). A cut-off point of ⩾10 mm2 for CSA-max yields both sensitivity and specificity of 88%. Conclusions. Ultrasonography can have a role not only in the diagnosis, but also in the severity stratification of patients with UNE.
Methylphenidate (MPH) is an important emerging pollutant found in effluents and wastewater. Thus, we aimed to develop and validate a method for detection and quantitation of MPH residues in sewage ...through high performance liquid chromatography coupled with photodiode array detector (LC-PDA). Here we describe a selective, accurate, precise, and valid method for determination of MPH in sewage with a total running time of 10 min, with limits of detection and quantification of 0.27 and 0.92 µg/mL, respectively. MPH retention peak was observed at 5 min. The method was applied to MPH analysis in a sewage sample pretreated with solid phase extraction, obtaining a result of 2.8 µg/L of MPH. Thus, the developed method can be considered feasible to be applied to MPH residual contamination analysis in sewage using a widely available apparatus.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
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