Classification of bloodstains deposited at different times on floor tiles using hierarchical modelling and a handheld NIR spectrometer.

Bloodstains are commonly encountered at crime scenes, especially on floor tiles, and can be deposited over different periods and intervals. Therefore, it is crucial to develop techniques that can accurately identify bloodstains deposited at different times. This study builds upon a previous investigation and aims to enhance the performance of three distinct hierarchical models (HMs) designed to differentiate and identify stains of human blood (HB), animal blood (AB), and common false positives (CFPs) on nine different types of floor tiles. Soft Independent Modeling Class Analogies (SIMCA), and Partial Least Squares-Discriminant Analysis (PLS-DA) were employed as decision rules in this process. The originally published model was constructed using a training set that included samples with a known time of deposit of six days. This model was then tested to predict samples with various deposition times, including human blood samples aged for 0, 1, 9, 20, 30, and 162 days, as well as animal blood samples aged for 0, 1, 10, 13, 20, 29, 105, and 176 days. To improve the identification of human blood, the models were modified by adding zero-day and one-day-old bloodstains to the original training set. All models showed improvement when fresher samples were included in the training set. The best results were achieved with the hierarchical model that used partial least squares-discriminant analysis as the second decision rule and incorporated one-day-old samples in the training set. This model yielded sensitivity values above 0.92 and specificity values above 0.7 for samples aged between zero and 30 days.

Hierarchical classification models and Handheld NIR spectrometer to human blood stains identification on different floor tiles.

One of the most important types of evidence in certain criminal investigations is traces of human blood. For a detailed investigation, blood samples must be identified and collected at the crime scene. The present study aimed to evaluate the potential of the identification of human blood in stains deposited on different types of floor tiles (five types of ceramics and four types of porcelain tiles) using a portable NIR instrument. Hierarchical models were developed by combining multivariate analysis techniques capable of identifying traces of human blood (HB), animal blood (AB) and common false positives (CFP). The spectra of the dried stains were obtained using a portable MicroNIR spectrometer (Viavi). The hierarchical models used two decision rules, the first to separate CFP and the second to discriminate HB from AB. The first decision rule, used to separate the CFP, was based on the Q-Residual criterion considering a PCA model. For the second rule, used to discriminate HB and AB, the Q-Residual criterion were tested as obtained from a PCA model, a One-Class SIMCA model, and a PLS-DA model. The best results of sensitivity and specificity, both equal to 100%, were obtained when a PLS-DA model was employed as the second decision rule. The hierarchical classification models built for these same training sets using a PCA or SIMCA model also obtained excellent sensitivity results for HB classification, with values above 94% and 78% of specificity. No CFP samples were misclassified. Hierarchical models represent a significant advance as a methodology for the identification of human blood stains at crime scenes.

Severity of Flare Reactions in Diethylenetriamine Pentaacetate Chelations: Report on Different Immune Dampening Strategies in Clinical Practice.

PURPOSE: The aim of this study was to report early clinical experience with various forms of immune dampening to mitigate the expected flare reaction in patients suffering from gadolinium deposition disease (GDD) receiving DTPA chelation. MATERIALS AND METHODS: All patients were clinical subjects, and no prospective research was performed on them. The study included 31 consecutive patients (21 women; age, 46.2 ± 12.5 years). The diagnosis of GDD was clinically made. The severity of the flare over the week after each chelation session was rated on a scale from 1 to 10 (where 1 is negligible, 10 is intolerably severe). Patients were followed for up to 5 chelation sessions. Four immune dampening strategies were used: (1) no concurrent treatment; (2) antihistamine plus montelukast (AH); (3) steroid/antihistamine taper postchelation (SAHT); and (4) steroid/antihistamine extending from prechelation to 5 days postchelation (extended hypersensitivity medication regimen; EHMR). The data were analyzed with generalized linear mixed models and with linear regression. RESULTS: A total of 102 flare scores were obtained at different time points. Ten patients underwent 5 chelations. The severity of the flare after the first chelation was significantly higher in cases of no concurrent therapy (8.4 ± 2.6) and AH (7 ± 1.4) compared with SAHT (6 ± 1.3) and EHMR (5 ± 1.1). Patients who underwent SAHT and EHMR experienced less severity of flare after the first chelation (P = 0.0049 and P = 0.0005, respectively). Considering all time points, the results were also significantly better with SAHT and EHMR. CONCLUSION: Based on early clinical experience, EHMR seems to manage flare reactions in DTPA chelation well. This strategy may represent the first standard therapy in patients with GDD.

Lateral hypothalamic activity indicates hunger and satiety states in humans.

Lateral hypothalamic area (LHA) local field potentials (LFPs) were recorded in a Prader-Willi patient undergoing deep brain stimulation (DBS) for obesity. During hunger, exposure to food-related cues induced an increase in beta/low-gamma activity. In contrast, recordings during satiety were marked by prominent alpha rhythms. Based on these findings, we have delivered alpha-frequency DBS prior to and during food intake. Despite reporting an early sensation of fullness, the patient continued to crave food. This suggests that the pattern of activity in LHA may indicate hunger/satiety states in humans but attest to the complexity of conducting neuromodulation studies in obesity.

Phenolic composition in different genotypes of Guabiju fruits (Myrcianthes pungens) and their potential as antioxidant and antichemotactic agents.

Fruits of Myrcianthes pungens Berg. Legr. (Myrtaceae), known as guabiju, are widely consumed fresh as well as dried, processed into jam, marmalade, and juices. In this study, chemical composition and antichemotactic and antioxidant activities of fruits from a wild type (GB) and 2 genotypes, PL2 and PL1, of guabiju were investigated. Total anthocyanins for the genotypes ranged from 334 to 531 mg/100 g dry weight (dwt). Total flavonoids and polyphenols ranged from 79.8 to 154 mg/100 g and 2438 to 4613 mg/100 g (dwt), respectively. A reversed phase liquid chromatography method with photodiode array detection was used to determine chemical profiles of the main anthocyanins found in the extracts. An HPLC method for the quantification of flavonoids is proposed, providing a simple procedure with rapid sample preparation. All samples contained 5 identical anthocyanidins, distributed differently, with cyanidin as the main compound. Identified flavonoids were quercitrin, hyperoside, and isoquercitrin; their relative amounts varied among the extracts. The antioxidant activity of guabiju methanolic extract was comparable to that of Trolox, and at a test concentration of 0.25 mg/mL, GB and PL2 activities were higher than those exhibited by Trolox. Total dry extracts of guabiju exhibited greater inhibition of chemotaxis at a concentration of 4 µg/mL, except for GBH (wild-type hydrolyzed extract) which already presented high values at a concentration of 2 µg/mL. These results suggest that the consumption of this fruit, rich in polyphenols, may be beneficial to human health. Practical Application: The paper is the first attempt on the improvement of this native fruit, since it is widely consumed regularly as part of the South American diet. The content of phenolic compounds demonstrates that consumption of guabiju would be beneficial to human health. Differences among samples, originating from open pollination of plants growing on the same site, lead to the conclusion that improvements can be made in the chemical composition and beneficial activity of guabiju fruits by simply selecting genotypes for these characteristics among open-pollinated seedlings.

Minor and unsystematic cortical topographic changes of attention correlates between modalities.

In this study we analyzed the topography of induced cortical oscillations in 20 healthy individuals performing simple attention tasks. We were interested in qualitatively replicating our recent findings on the localization of attention-induced beta bands during a visual task [1], and verifying whether significant topographic changes would follow the change of attention to the auditory modality. We computed corrected latency averaging of each induced frequency bands, and modeled their generators by current density reconstruction with Lp-norm minimization. We quantified topographic similarity between conditions by an analysis of correlations, whereas the inter-modality significant differences in attention correlates were illustrated in each individual case. We replicated the qualitative result of highly idiosyncratic topography of attention-related activity to individuals, manifested both in the beta bands, and previously studied slow potential distributions [2]. Visual inspection of both scalp potentials and distribution of cortical currents showed minor changes in attention-related bands with respect to modality, as compared to the theta and delta bands, known to be major contributors to the sensory-related potentials. Quantitative results agreed with visual inspection, supporting to the conclusion that attention-related activity does not change much between modalities, and whatever individual changes do occur, they are not systematic in cortical localization across subjects. We discuss our results, combined with results from other studies that present individual data, with respect to the function of cortical association areas.

Complex slow potential generators in a simplified attention paradigm.

We have recently obtained evidence for complex multifocal, individually variable generators of slow cortical potentials, elicited during performance of visual tasks involving expecting attention, comparison and memory [Basile, L.F.H., Ballester, G., Castro, C.C., and Gattaz, W.F., 2002. Multifocal slow potential generators revealed by high-resolution EEG and current density reconstruction. Int. J. Psychophysiol., 45 (3), 227-240; Basile, L.F.H, Baldo, M.V., Castro, C.C., and Gattaz, W.F. 2003. The generators of slow potentials obtained during verbal, pictorial and spatial tasks. Int. J. Psychophysiol., 48, 55-65]. The cue-target aspect of traditional paradigms for attention studies is equivalent to 'warning S1'-'imperative S2' in slow potential designs. We simplified Posner's spatial cueing task [Posner, M.I. 1980. Orienting of attention.Q. J. Exp. Psychol. Feb;32 (1), 3-25; Posner, M.I., Snyder, C.R., Davidson, B.J. 1980. Attention and the detection of signals. J Exp Psychol. Jun; 109 (2), 160-174] to temporal cuing only, by using visual cues to indicate the mere presence, on a known central position, of the eventual target (17 ms duration, +/-0.3 degrees grey circle). We recorded slow potentials on 12 healthy subjects, by 124-channel EEG system (Neuroscan Inc.), and modeled their generators using current density reconstruction (CDR) by L(p) 1.2 norm minimization ("Curry V4.6", Neurosoft Inc.) applied to the target onset time. MRIs were obtained for each subject for constraining source models to individual brain anatomy. Average slow potentials were computed from above 60 artifact-free EEG-epochs (ISI=1.6 s, average ITI=2.5 s). We tabulated individual cortical current distributions by cytoarchitectonic area of Brodmann, after scaling into negligible, low, moderate and strong local density, based on percentile bands with respect to absolute maximum current. Despite the task's simplicity, the main result was individual variability and complexity in both scalp voltage and cortical current distributions. As observed in our previous studies, there was strong intersubject variability in the exact distribution of task-related cortical activity. Only parietal area 7 bilaterally was non-negligibly active in all subjects (currents above 10% maximum). As opposed to drawing conclusions based on group averaged data, we propose that activity by cytoarchitectonic area be ranked and statistically analysed only after being scaled on each individual. Based on the present results, the concept of a universal attention-related set of cortical areas if restricted to common areas across subjects is challenged, since even area 7 may no longer be common when the sample size becomes larger. We discuss the fact that group averaging may de-emphasize weakly but consistently active areas, and emphasize strongly but inconsistently active ones.

Vigilancia epidemiológica intensificada de influenza / Intensified epidemiological surveillance of influenza

Se presentan los resultados del Proyecto de Investigación para Vigilancia Epidemiológica de Influenza, realizado durante la temporada gripal de 1983.Se estudiaron los soldados de la clase 1964 que aquejaron síndrome gripal. Sobre 34 muestras de sueros pareados se obtubieron 24 conversiones serológicas, 14 de las cuales correspondieron a la cepa A/England/333/80 con títulos significativos que podrían señalar la presencia de un brote originado por la misma y otra similar (AU)

Vigilancia epidemiológica intensificada de influenza / Intensified epidemiological surveillance of influenza

Se presentan los resultados del Proyecto de Investigación para Vigilancia Epidemiológica de Influenza, realizado durante la temporada gripal de 1983.Se estudiaron los soldados de la clase 1964 que aquejaron síndrome gripal. Sobre 34 muestras de sueros pareados se obtubieron 24 conversiones serológicas, 14 de las cuales correspondieron a la cepa A/England/333/80 con títulos significativos que podrían señalar la presencia de un brote originado por la misma y otra similar