Deconstruction of Neurotrypsin Reveals a Multi-factorially Regulated Activity Affecting Myotube Formation and Neuronal Excitability

Neurotrypsin (NT) is a highly specific nervous system multi-domain serine protease best known for its selective processing of the potent synaptic organizer agrin. Its enzymatic activity is thought to influence processes of synaptic plasticity, with its deregulation causing accelerated neuromuscular junction (NMJ) degeneration or contributing to forms of mental retardation. These biological effects are likely to stem from NT-based regulation of agrin signaling. However, dissecting the exact biological implications of NT-agrin interplay is difficult, due to the scarce molecular detail regarding NT activity and NT-agrin interactions. We developed a strategy to reliably produce and purify a catalytically competent engineered variant of NT called "NT-mini" and a library of C-terminal agrin fragments, with which we performed a thorough biochemical and biophysical characterization of NT enzyme functionality. We studied the regulatory effects of calcium ions and heparin, identified NT's heparin-binding domain, and discovered how zinc ions induce modulation of enzymatic activity. Additionally, we investigated myotube differentiation and hippocampal neuron excitability, evidencing a dose-dependent increase in neuronal activity alongside a negative impact on myoblast fusion when using the active NT enzyme. Collectively, our results provide in vitro and cellular foundations to unravel the molecular underpinnings and biological significance of NT-agrin interactions

Protocolos de regulação ambulatorial : psiquiatria adulto

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Oral manifestation of tuberculosis: a case-report

AbstractThe present case-report describes tuberculosis on the oral mucosa, in a rare manifestation of the disease. The importance of appropriate diagnosis and awareness of the clinical manifestations is highlighted. Oral lesions seem to occur as chronic ulcers, nodular or granular areas, and rare, firm leukoplakia regions. Most extra-pulmonary lesions represent secondary infections of a primary lung infectious focus; therefore, early and accurate diagnosis is required for planning of the best treatment and strategies to control the disease

RELATEC : Revista latinoamericana de tecnología educativa

Resumen en inglésResumen basado en el de la publicaciónSe presentan las principales aportaciones de un estudio realizado sobre la utilización de diferentes medios tecnológicos realizada por una muestra de profesores y profesoras universitarias. Entre las categorías que ayudan a entender los usos de dichas herramientas en las prácticas docentes está la finalidad instructiva o formativa de los mismos, las estrategias organizativas utilizadas en los centros para ubicar los medios y, finalmente, la formación y apoyo técnico disponible en las mencionadas instituciones de enseñanza superiorES

Protein signature in cerebrospinal fluid and serum of Alzheimer’s disease patients: The case of apolipoprotein A-1 proteoforms

<div><p>In the diagnosis of Alzheimer’s disease (AD) total tau (T-tau), tau phosphorylated at threonine 181 (P-tau181), and the 42 amino acid isoform of alpha β-amyloid (Aβ) are well established surrogate CSF markers. However, there is a constant need for new diagnostic markers to identify the disease at a very early stage. The identification of new molecules for AD diagnosis and monitoring in CSF is hampered by several “confounding” factors including intra- and inter-individual, pre-analytical and analytical variabilities. In an attempt to partially overcome patient’s variability and to determine new molecules significantly dysregulated in CSF, we assessed the proteome profile of low molecular weight protein species in CSF and serum of the same patients. CSFs and sera from 36 ADs, 32 iNPHs (idiopathic normal pressure hydrocephalus) and 12 controls were compared by MALDI profiling (non-parametric statistics, CV<20%, AUC>0.750). After protein identification by mass spectrometry, the proteoform composition was assessed by 2-D DIGE/MS. Results indicated that CSF of iNPH can be used as control. Serum and CSF of AD patients shows a specific protein profile compared to iNPH samples. A variation (p<0.01) of Apo A-1 levels in AD, together with a specific dysregulation of Apo A-1 proteoforms was observed. The profiling of CSF and serum of the same patients, suggests that the decrement of total Apo A-1 occurs specifically in CSF. Serum and CSF of AD shows a characteristic Apo A-1 proteoform pattern suggesting it as potential marker which can support the clinical workflow adopted for AD diagnosis and progression.</p></div

Heterogeneous response of cardiac sympathetic function to cardiac resynchronization therapy in heart failure documented by 11[C]-hydroxy-ephedrine and PET/CT

Introduction: Cardiac resynchronization therapy (CRT) is an accepted treatment in patients with end-stage heart failure. PET permits the absolute quantification of global and regional homogeneity in cardiac sympathetic innervation. We evaluated the variation of cardiac adrenergic activity in patients with idiopathic heart failure (IHF) disease (NYHA III-IV) after CRT using 11C-hydroxyephedrine (HED) PET/CT. Methods: Ten IHF patients (mean age. = 68; range. = 55-81; average left ventricular ejection fraction 26 ± 4%) implanted with a resynchronization device underwent three HED PET/CT studies: PET 1 one week after inactive device implantation; PET 2, one week after PET 1 under stimulated rhythm; PET 3, at 3 months under active CRT. A dedicated software (PMOD 3.4 version) was used to estimate global and regional cardiac uptake of HED through 17 segment polar maps. Results: At baseline, HED uptake was heterogeneously distributed throughout the left ventricle with a variation coefficient of 18 ± 5%. This variable markedly decreased after three months CRT (12 ± 5%, p. &lt;. 0.01). Interestingly, subdividing the 170 myocardial segments (17 segments of each patient multiplied by the number of patients) into two groups, according to the median value of tracer uptake expressed as % of maximal myocardial uptake (76%), we observed a different behaviour depending on baseline innervation: HED uptake significantly increased only in segments with "impaired innervation" (SUV 2.61 ± 0.92 at PET1 and 3.05 ± 1.67 at three months, p. &lt;. 0.01). Conclusion: As shown by HED PET/CT uptake and distribution, improvement in homogeneity of myocardial neuronal function reflected a selective improvement of tracer uptake in regions with more severe neuronal damage. Advances in Knowledge: These finding supported the presence of a myocardial regional variability in response of cardiac sympathetic system to CRT and a systemic response involving remote tissues with rich adrenergic innervation. Implication for patient care: This work might contribute to identify imaging parameters that could predict the response to CRT therapy

Dysregulated peaks in AD vs iNPH comparison.

<p>Upper panel: differentially expressed peaks (p<0.05) in CSF of AD vs iNPH patients. For each peak, p-value obtained adopting a non-parametric test (Wilcoxon test), class average areas and CVs are indicated. Lower panel: changed peaks expression in CSF reported as ln of the ratio of the average area for each class. Asterisks and dots indicate dysregulated peaks both in CSF (see paragraph “CSF MALDI profiling of selected cohorts”) and in serum (see paragraph “Protein levels of total Apo A-1 in serum”) with same/opposite trend, respectively.</p

PCA score plot relating to healthy controls <i>vs</i> iNPHs comparison.

<p>PCA plot is based on the CSF profiling of healthy subjects (black circles) and iNPH patients (grey circles). The analysis, performed by using ClinProTools software showed the absence of clusterization of the two classes.</p

Participants demography.

<p>Participants demography.</p

CSF MALDI profiling of AD <i>vs</i> iNPHs.

<p>Representative MALDI profiling spectrum of CSF from AD (average spectrum, red line) and iNPH patients (average spectrum, green line). Samples were spotted onto the AnchorChip target (Bruker Daltonics) using DHAP matrix as described in method section. The corresponding PCA plot showed a good separation between the considered classes (AD, red circles; iNPH, green circles).</p