Muscle Proteomic Profile before and after Enzyme Replacement Therapy in Late-Onset Pompe Disease

Mutations in the acidic alpha-glucosidase (GAA) coding gene cause Pompe disease. Late-onset Pompe disease (LOPD) is characterized by progressive proximal and axial muscle weakness and atrophy, causing respiratory failure. Enzyme replacement therapy (ERT), based on recombinant human GAA infusions, is the only available treatment; however, the efficacy of ERT is variable. Here we address the question whether proteins at variance in LOPD muscle of patients before and after 1 year of ERT, compared withhealthy age-matched subjects (CTR), reveal a specific signature. Proteins extracted from skeletal muscle of LOPD patients and CTR were analyzed by combining gel based (two-dimensional difference gel electrophoresis) and label-free (liquid chromatography-mass spectrometry) proteomic approaches, and ingenuity pathway analysis. Upstream regulators targeting autophagy and lysosomal tethering were assessed by immunoblotting. 178 proteins were changed in abundance in LOPD patients, 47 of them recovered normal level after ERT. Defects in oxidative metabolism, muscle contractile protein regulation, cytoskeletal rearrangement, and membrane reorganization persisted. Metabolic changes, ER stress and UPR (unfolded protein response) contribute to muscle proteostasis dysregulation with active membrane remodeling (high levels of LC3BII/LC3BI) and accumulation of p62, suggesting imbalance in the autophagic process. Active lysosome biogenesis characterizes both LOPD PRE and POST, unparalleled by molecules involved in lysosome tethering (VAMP8, SNAP29, STX17, and GORASP2) and BNIP3. In conclusion this study reveals a specific signature that suggests ERT prolongation and molecular targets to ameliorate patient’s outcome.     

Touch cytology. A reliable and cost-effective method for diagnosis of Helicobacter pylori infection

A variety of reliable methods are available for detecting Helicobacter pylori (Hp) during upper gastrointestinal endoscopy. We evaluated the clinical utility and cost-effectiveness of rapid urease test (RUT), touch cytology (TC), and histology (H). Two hundred thirty-eight consecutive patients (178 without previous medical treatment and 60 formerly treated with anti-Hp therapy) were tested for Hp infection by RUT, TC, and H (H&E stain). The infection status for each patient was established by a concordance of two test results. The time to carry out the three tests and their cost were also calculated. Sensitivity of TC (100%) was significantly higher than that of RUT (86.8%; P < 0.001), but not than that of H (94.9%). RUT was significantly more specific than H (100% vs 95.6%; P < 0.05), but not than TC (96.4%). Hp infection was more frequent in the patients with chronic active gastritis than in those with chronic nonactive gastritis (P < 0.001). No Hp infection was detected in absence of chronic antral inflammation. RUT resulted the cheapest method and H the most expensive; TC is faster and cheaper than H. When additional information about the severity of mucosal damage or the presence of cell atypias is not necessary, histologic examination can be omitted, and a cost-effective strategy for assessing Hp status might consist in taking two antral biopsies, the former for performing RUT and the latter for preparing a slide by TC, which should be stained and examined only when the RUT result is negative.     

A multilayer perceptron solution to the match phase problem inrule-based artificial intelligence systems

In rule-based artificial intelligence (AI) planning, expert, and learning systems, it is often the case that the left-hand-sides of the rules must be repeatedly compared to the contents of some working memory. Normally, the intent is to determine which rules are relevant to the current situation (i.e., to find the conflict set). A technique using a multilayer perceptron to solve the match phase problem for rule-based AI systems is presented. A syntax for premise formulas (i.e., the left-hand-sides of the rules) is defined, and working memory is specified. From this, it is shown how to construct a multilayer perceptron that finds all of the rules which can be executed for the current situation in working memory. The complexity of the constructed multilayer perceptron is derived in terms of the maximum number of nodes and the required number of layers. A method for reducing the number of layers to at most three is presented     

Drying of Seeds and Gels

In an attempt to contribute to the integration of research that deals with the drying of seeds and gels, the aim of the present study is to analyze the drying of porous particles covered with a gel layer, whether natural or artificial. Two case studies are presented. In the first case, the emphasis is to study the combined effect of heat and mass transfer and the shrinkage in the drying of mucilaginous seeds. The focus of the second case study is the development of an experimental methodology for coating seeds with a gel-based polymer.     

Demonstration that venous occlusion fails to release von Willebrand factor multimers

The acute simultaneous release of tissue plasminogen activator (t-PA) and von Willebrand factor (vWF) from endothelial cells in response to a variety of agonists including thrombin, DDAVP, histamine and adrenalin has been described. In the present study we investigated the effect of venous occlusion on the circulating levels of t-PA and vWF, as well as the molecular organization of vWF in 20 normal subjects. After occlusion a significant increase in plasma t-PA levels was observed even after the values were corrected for haemoconcentration. Venous occlusion also enhanced plasma vWF values, but the increase was abolished when the correction for haemoconcentration was introduced. Following venous occlusion, no circulating abnormally large vWF multimers were detected in the subjects studied. These forms are normally not present in the circulation and are released from endothelial cells through the regulated vWF pathway; their absence therefore seems to demonstrate that this pathway is not activated after venous occlusion. Since occlusion does not enhance vWF synthesis, the increase in vWF observed in the subjects investigated may be fully attributed to haemoconcentration.     

An IIR median hybrid filter

A new class of nonlinear filters, the multidirectional infinite impulse response median hybrid (MIMH) filters, is presented and analyzed. The input signal is processed twice using a linear shift-invariant (LSI) infinite impulse response (IIR) filtering module: once with normal causality and a second time with inverted causality. The final output of the MIMH filter is the median of the two-directional outputs and the original input signal. Thus, the MIMH filter is a concatenation of linear filtering (a LSI IIR filtering module) and nonlinear filtering (a median filtering module). Because of this unique scheme, the MIMH filter possesses many desirable properties which are both proven and analyzed (including impulse removal, step preservation, and noise suppression). A comparison to other medium-type filters is also provided