APP processing and b-amyloid deposition in sporadic Creutzfeldt-Jakob patients is dependent on Dab1.

Alzheimer"s disease and prion pathologies (e.g., Creutzfeldt-Jakob disease (CJD)) display profound neural lesions associated with aberrant protein processing and extracellular amyloid deposits. Dab1 has been implicated in the regulation of Amyloid Precursor Protein (APP), but a direct link between human prion diseases and Dab1/APP interactions has not been published. Here we examined this putative relationship in seventeen cases of sporadic CJD (sCJD) post mortem. Biochemical analyses of brain tissue revealed two groups, which also correlated with PrPsc types 1 and 2. One group, with PrPsc type 1 showed increased Dab1 phosphorylation, and lower CTF production with an absence of A deposition. The second sCJD group, which carried PrPsc type 2, showed lower levels of Dab1 phosphorylation and CTF production, and A deposition. Thus, the present observations suggest a correlation between Dab1-phosphorylation, A deposition and PrPsc type in sCJD.

A radiochemical method for carbamoyl-phosphate synthetase I: application to rats fed a hyperproteic diet

A method for the measurement of carbamoyl-phosphate synthetase I activity in animal tissues has been developed using the livers of rats under normal and hyperproteic diets. The method is based on the incorporation of 14C-ammonium bicarbonate to carbamoyl-phosphate in the presence of ATP-Mg and N-acetyl-glutamate. The reaction is stopped by chilling, lowering the pH and adding ethanol. Excess bicarbonate is flushed out under a gentle stream of cold CO2. The only label remaining in the medium was that incorporated into carbamoyl-phosphate, since all 14C-CO2 from bicarbonate was eliminated. The method is rapid and requires only a low pressure supply of CO2 to remove the excess substrate. The reaction is linear up to 10 min using homogenate dilutions of 1:20 to 1:200 (w/v). Rat liver activity was in the range of 89±8 nkat/g. Hyperproteic diet resulted in a significant 1.4-fold increase. The design of the method allows for the processing of multiple samples at the same time, and incubation medium manipulation is unnecessary, since the plastic incubation vial and its contents are finally counted together.

Estimación de funciones no lineales en mezclas post-no lineales

This paper proposes a new method for blindly inverting a nonlinear mapping which transforms a sum of random variables. This is the case of post-nonlinear (PNL) source separation mixtures. The importance of the method is based on the fact that it permits to decouple the estimation of the nonlinear part from the estimation of the linear one. Only the nonlinear part is inverted, without considering on the linear part. Hence the initial problem is transformed into a linear one that can then be solved with any convenient linear algorithm. The method is compared with other existing algorithms for blindly approximating nonlinear mappings. Experiments show that the proposed algorithm outperforms the results obtained with other algorithms and give a reasonably good linearized data

Therapeutic benefits of body percussion using the BAPNE method

Body percussion using to the BAPNE method is a means of cognitive stimulation with multiple applications. The aim of this research is to assess their full potential as a source of therapy. The methodology used is theoretical in nature and makes use of a wide bibliography to find evidence for its therapeutic effect. In essence, body percussion can be seen to lead to improvements in three areas. the Physical, as it stimulates awareness of the body, control of movement and muscular strength, coordination and balance; the Mental, as it improves concentration, memory and perception; and finally Socio-affective, as it helps to build egalitarian relationships and leads to a decrease in anxiety in social interactions. This means of therapy has several different uses and it is targeted at different groups. In the present investigation we categorise them into five main groups: individuals with neurodegenerative diseases like Alzheimer's or Parkinson's disease; individuals with learning disorders such as dyslexia or ADHD; patients affected by diseases of the spinal cord, cranial neuropathies and trauma (Neurorehabilitation); and for the treatment of addictive behavior (addiction); and depressive disorders or anxiety disorders.After thorough analysis, we have found scientific evidence that the therapeutic body percussion using the BAPNE method improves the quality of life of patients and it is an important factor in stabilizing the development of different diseases.In addition, evidence involving certain biological indicators (in control and experimental groups, and through a pre-test and post-test) show its effect on levels of stress and anxiety (reduction of cortisol), as well as improvement of social relations as a result of working as a group (increased levels of oxytocin), and improvements seen in self-esteem and in a variety of personal aspects through the Aspects of Identity questionnaire.

Different Storing and Processing Conditions of Human Lymphocytes do not Alter P-Glycoprotein Rhodamine 123 Efflux.

P-glycoprotein (Pgp), a protein codified by Multi Drug Resistance (MDR1) gene, has a detoxifying function and might influence the toxicity and pharmacokinetics and pharmacodynamics of drugs. Sampling strategies to improve Pgp studies could be useful to optimize the sensitivity and the reproducibility of efflux assays. This study aimed to compare Pgp expression and efflux activity by measuring Rhodamine123 (Rh123) retention in lymphocytes stored under different conditions, in order to evaluate the potential utility of any of the storing conditions in Pgp functionality. Our results show no change in protein expression of Pgp by confocal studies and Western blotting, nor changes at the mRNA level (qRT-PCR). No differences in Rh123 efflux by Pgp activity assays were found between fresh and frozen lymphocytes after 24 hours of blood extraction, using either of the two Pgp specific inhibitors (VP and PSC833). Different working conditions in the 24 hours post blood extraction do not affect Rh123 efflux. These results allow standardization of Pgp activity measurement in different individuals with different timing of blood sampling and in different geographic areas. _______________

A Computer program for estimating population size by the removal method

A BASIC computer program (REMOVAL) was developed to compute in a VAXNMS environment all the calculations of the removal method for population size estimation (catch-effort method for closed populations with constant sampling effort). The program follows the maximum likelihood methodology,checks the failure conditions, applies the appropriate formula, and displays the estimates of population size and catchability, with their standard deviations and coefficients of variation, and two goodness-of-fit statistics with their significance levels. Data of removal experiments for the cyprinodontid fish Aphanius iberus in the Alt Emporda wetlands are used to exemplify the use of the program

Image Segmentation Using Information Bottleneck Method

In image processing, segmentation algorithms constitute one of the main focuses of research. In this paper, new image segmentation algorithms based on a hard version of the information bottleneck method are presented. The objective of this method is to extract a compact representation of a variable, considered the input, with minimal loss of mutual information with respect to another variable, considered the output. First, we introduce a split-and-merge algorithm based on the definition of an information channel between a set of regions (input) of the image and the intensity histogram bins (output). From this channel, the maximization of the mutual information gain is used to optimize the image partitioning. Then, the merging process of the regions obtained in the previous phase is carried out by minimizing the loss of mutual information. From the inversion of the above channel, we also present a new histogram clustering algorithm based on the minimization of the mutual information loss, where now the input variable represents the histogram bins and the output is given by the set of regions obtained from the above split-and-merge algorithm. Finally, we introduce two new clustering algorithms which show how the information bottleneck method can be applied to the registration channel obtained when two multimodal images are correctly aligned. Different experiments on 2-D and 3-D images show the behavior of the proposed algorithms