Neural activity underlying the detection of an object movement by an observer during forward self-motion: Dynamic decoding and temporal evolution of directional cortical connectivity.

Relatively little is known about how the human brain identifies movement of objects while the observer is also moving in the environment. This is, ecologically, one of the most fundamental motion processing problems, critical for survival. To study this problem, we used a task which involved nine textured spheres moving in depth, eight simulating the observer's forward motion while the ninth, the target, moved independently with a different speed towards or away from the observer. Capitalizing on the high temporal resolution of magnetoencephalography (MEG) we trained a Support Vector Classifier (SVC) using the sensor-level data to identify correct and incorrect responses. Using the same MEG data, we addressed the dynamics of cortical processes involved in the detection of the independently moving object and investigated whether we could obtain confirmatory evidence for the brain activity patterns used by the classifier. Our findings indicate that response correctness could be reliably predicted by the SVC, with the highest accuracy during the blank period after motion and preceding the response. The spatial distribution of the areas critical for the correct prediction was similar but not exclusive to areas underlying the evoked activity. Importantly, SVC identified frontal areas otherwise not detected with evoked activity that seem to be important for the successful performance in the task. Dynamic connectivity further supported the involvement of frontal and occipital-temporal areas during the task periods. This is the first study to dynamically map cortical areas using a fully data-driven approach in order to investigate the neural mechanisms involved in the detection of moving objects during observer's self-motion.

A new technique associated with the evaporimetry method for evaluating occlusion.

The stratum corneum is the outermost layer of the skin. It constitutes a permeability barrier that keeps micro-organisms and toxic agents from entering the skin, while retaining water and electrolytes. In order to preserve its colour and elasticity, the skin needs lipids and water. Certain occlusive products in contact with the skin diminish its natural transepidermal water loss (TEWL), and the occlusion potential of such products can be evaluated with the aid of evaporimetry. The purpose of this work was to increase the sensitivity of the method by associating the well-established methodology for measuring TEWL with a technique for removing occlusive products from the skin. The present study was designed to evaluate the procedure of measuring TEWL evaporimetrically (the traditional method) in comparison with our new method, which employs the same evaporimetric measurement combined with a removal technique that uses cotton to remove the physical barrier that occlusive products form on the skin. The product used in this study was solid petrolatum (petroleum jelly), which possesses well-known occlusive properties. The TEWL measurements were made over a pre-defined period of time, on different skin sites, and were systematically compared with the results generated by an untreated control site. The TEWL was first determined by the classic method (without product removal), then the product was removed and new readings were taken. Our results show that the classic technique was unable to show a statistical distinction between the occlusion capability of solid petrolatum and the untreated control site, whereas this same method used in association with product removal provided a statistically significant difference between the TEWL measured on the occluded and control sites. Therefore, our removal technique associated with the traditional method for measuring TEWL proved capable of increasing the response sensitivity of evaporimetry with occlusive products.

Protein loss quantification of abraded virgin and abraded bleached hair according to Bradford assay.

This study intends to present Bradford assay as an alternative to Lowry test to quantify hair damage during combing or brushing. The protocol involves collecting hair fragments that are chipped away from hair during these abrasive treatments and quantitatively measuring the amount of protein using an analytical procedure to detect low amounts of proteins. This protein determination method involves the binding of Coomassie Brilliant Blue G-250 to hair protein (keratin). It is quite rapid and sensitive and less prone to interferences as the standard Lowry procedure. The latter is subject to interference from compounds such as lipids, cationic surfactants and EDTA, which are ingredients commonly used in hair care formulations and may lead to a false positive result. These drawbacks should be eliminated when using the so called Bradford method for hair protein quantitation. Our studies showed reproducible results for human hair protein and the developed color was stable for up to one hour. The data also show that virgin hair releases less protein than bleached hair. The amount detected for the former after combing ranges from 0.875 to 1.03 mg/g of hair and 4.85 to 5.35 mg/g of hair for the latter.

Outcome of treatment in adult acute lymphoblastic leukemia in southern Brazil using a modified german multicenter acute lymphoblastic leukemia protocol.

Reports on treatment outcomes in adults with acute lymphoblastic leukemia (ALL) in Brazil are sparse. To evaluate the outcome of patients with ALL managed by the public healthcare system, we studied 42 adults treated from 1990 to 1997 in the Division of Hematology at Hospital de Clínicas, Porto Alegre, Brazil. Of these patients, 14/42 were females and their median age at diagnosis was 26 (17-64) years. The diagnosis of ALL was based on cytological examination of marrow smears, and immunophenotypic and cytogenetic studies, when available. Fifty percent of the patients expressed CD10, 30% were CD10 negative and CD19 positive and 20% expressed T markers. Philadelphia chromosome was found in 4 (7.14%). The chemotherapy protocol was adapted from the German Multicenter ALL (GMALL) 02-84 protocol. The complete remission rate was 93% and the overall survival at 5 years was 41%. No particular risk factor was identified in our series. These results are comparable to the findings of other international studies.