Apex Peptide Elution Chain Selection: A New Strategy for Selecting Precursors in 2D-LC-MALDI-TOF/TOF Experiments on Complex Biological Samples

LC-MALDI provides an often overlooked opportunity to exploit the separation between LC-MS and MS/MS stages of a 2D-LC-MS-based proteomics experiment, that is, by making a smarter selection for precursor fragmentation. Apex Peptide Elution Chain Selection (APECS) is a simple and powerful method for intensity-based peptide selection in a complex sample separated by 2D-LC, using a MALDI-TOF/TOF instrument. It removes the peptide redundancy present in the adjacent first-dimension (typically strong cation exchange, SCX) fractions by constructing peptide elution profiles that link the precursor ions of the same peptide across SCX fractions. Subsequently, the precursor ion most likely to fragment successfully in a given profile is selected for fragmentation analysis, selecting on precursor intensity and absence of adjacent ions that may cofragment. To make the method independent of experiment-specific tolerance criteria, we introduce the concept of the branching factor, which measures the likelihood of false clustering of precursor ions based on past experiments. By validation with a complex proteome sample of Arabidopsis thaliana, APECS identified an equivalent number of peptides as a conventional data-dependent acquisition method but with a 35% smaller work load. Consequently, reduced sample depletion allowed further selection of lower signal-to-noise ratio precursor ions, leading to a larger number of identified unique peptides.

Trans-nasal endoscopic and intra-oral combined approach for odontogenic cysts

Maxillary cysts are a common finding in maxillofacial surgery, dentistry and otolaryngology. Treatment is surgical; a traditional approach includes Caldwell-Luc and other intra-oral approaches. In this article, we analyse the outcomes of 9 patients operated on using a combined intra-oral and trans-nasal approach to the aforementioned disease. Although the number of patients is small, the good results of this study suggest that the combined approach might be a reliable treatment option

Trans-trapezium carpo-metacarpal dislocation of the thumb

We report a case of carpo-metacarpal dislocation associated with an isolated horizontal fracture of the trapezium. It is a rare lesion which is difficult to diagnose by standard radiography, and CT may be necessary for the diagnosis and correct treatment. In our case, stable osteosynthesis was achieved by internal screw fixation, and at follow-up there was an unrestricted, painless range of motion of the thum

Gallstone ileus treated with non-surgical conservative methods: a case report

INTRODUCTION: The preoperative diagnosis of gallstone ileus is challenging due to the variability of its presentation, often resulting in late diagnosis. Controversy remains regarding the management of gallstone ileus; surgery is the standard treatment, but also less invasive approaches have proven to be successful. We present an unusual case of gallstone ileus and its conservative treatment. CASE PRESENTATION: We describe the case of a 49-year-old Caucasian woman with a bowel sub-occlusion, treated conservatively. The imaging technique (plain abdominal X-ray and computed tomography scan) led to a diagnosis of gallstones ileus. A surgical intervention was not performed. Instead, she underwent extracorporeal shock-wave lithotripsy to fragment the stones, mechanical intestinal dilatation for ileocolic stenosis and endoscopic removal of the gallstone. The presence of an apricot shell contributed to the bowel occlusion and was removed. The intervention was successful and without complications. CONCLUSIONS: Given the variability of the gallstone ileus presentation, surgery could not be the only treatment for our patient. In our case report, we show that colonoscopy could be a non-invasive approach that allows for diagnosis and treatment at the same time. The available data do not show a higher rate of recurrent biliary disease in cases where this method has been used, therefore in select patients, a conservative treatment could be an effective solution

The experience as a problem in football

En el fútbol argentino, la experiencia se presenta como principio de autoridad supremo, convalidando las acciones de su orden, organizando y sosteniendo su estructura, y determinando la mayoría de decisiones institucionales. Colocar a la experiencia por sobre la teoría no solo es anular la atadura histórica que tiene la práctica y los sujetos, sino es la subestimación de lo novedoso. Esto constituye un problema del orden político en el fútbol, porque la experiencia no cuestiona, sino que reproduce el orden instituido. De este modo, el fútbol disminuye las probabilidades de ser alterado tanto en su organización política como en sus enunciados epistémicos. La idea de la siguiente presentación es detenerse aquí para problematizar la situación mencionada: el triunfo de la experiencia vivencial sobre la teoría, el vaciamiento con el saber teórico que ningunea algún cambio posible.In the Argentinian football, the experience is presented as a supreme principle of authority, validating the actions of its order, organizing and supporting its structure, and determining the majority of institutional decisions. To place experience above theory is not only to nullify the historical ties between practice and subjects, but also to underestimate what is new. This contributes to create a political problem, because the experience does not question, but reproduces the instituted order. In this way, football reduces the chances of being changed/altered both in its political organization and epistemic statements. The main idea of the following presentation is to problematize the mentioned situation: the triumph of the experience over the theory, the emptying of the theoretical knowledge that does not make any possible change.Facultad de Periodismo y Comunicación Socia

Elaboration of a kinetic model in order to predict the molecular and isotopic composition of natural gas generated during the thermal cracking of hydrocarbons

The scope of the present study was to validate an approach that could be used to elaborate a model that would predict the δ[superscript]13C of the gases generated during thermal cracking of oil. The attention was focused on C[subscript]14- methylaromatics and alkylaromatics but the entire methodology was demonstrated on one component i.e. 1,2,4-trimethylbenzene.Pyrolysis experiments at temperatures of 395, 425, 450, and 475 °C and at a pressure of 100 bar were performed in order to study the whole range of conversions. All pyrolysis fractions were recovered and quantified. All identified products were also quantified individually. A free-radical mechanism until 70% conversion of 1,2,4-trimethylbenzene was achieved. This mechanism was then used to characterize some CH[subscript]4 generation pathways at 425 and 200 °C. In both cases the identified pathways included: (i) demethylation of 1,2,4- trimethylbenzene into xylenes (and to a lesser extent demethylation of xylenes into toluene), (ii) dimerizarion of monoaromatics, (iii) intramolecular ring closure reaction of dimers into triaromatics.In a second step, the free-radical mechanism was used to constrain the chemistry of a simpler lumped kinetic model predicting CH[subscript]4 generation under laboratory and geological conditions for the whole range of conversions. The resulting scheme was composed of four pathways P[subscript]i for methane generation: Reactant --> Dimers (P[subscript]a), Reactant --> Xylenes (P[subscript]b), Dimers --> {Prechar + Char} (P[subscript]c), and Xylenes --> Dimers + Toluene (P[subscript]d). Optimization yielded activation energies in the range of 50-60 kcal/mol, and frequency factors in the neighbourhood of 10[superscript]12 s[superscript]-1. Simulations revealed that P[subscript]b and P[subscript]c led to the greatest amounts of CH[subscript]4 below 5% conversion, followed by P[subscript]a. Above 5% conversion, CH[subscript]4 generated via P[subscript]c became dominant but P[subscript]a and P[subscript]b were also found to be of importance. Contribution of P[subscript]d was found to be negligible, except for when 100% conversion was almost reached. Simulations under geological heating rates revealed that significant amounts of CH[subscript]4 were generated by methylated monoaromatics in deeply buried reservoirs and that methylated monoaromatics thus had a higher thermal stability than their polyaromatic counterparts but lower than the saturated hydrocarbons.CH[subscript]4 yield was also modelled using a unique stoichiometric equation (CH[subscript]4max = 7.6 wt% per methyl group) associated with Ea = 58.5 kcal/mol and A = 10[superscript]11.96 s[superscript]-1, showing relative similarities to other reported values for methylated polyaromatics. In the final stage, P[subscript]a, P[subscript]b, and P[subscript]c were selected as relevant contributions to δ[superscript]13C[subscript]CH4 until 100% conversion. Kinetics for the generation of [superscript]12CH[subscript]4 and [superscript]13CH[subscript]4 were then expressed separately and implemented into the lumped model. Optimization yielded a ratio of frequency factors Ω = 1.028, variations of activation energy ΔE[subscript]i in the range of 36-79 cal/mol (kinetic effect); and a δ[superscript]13C[subscript]p of CH[subscript]4 precursor groups equal to -32.7‰ (precursor effect). Simulations performed under geological heating rates illustrated the greater isotopic fractionation of CH[subscript]4 generated under geological conditions compared with laboratory conditions. The comparison at high maturity with δ[superscript]13C[subscript]CH4 during thermal cracking of 1-methylpyrene and mature kerogen under the same simulation conditions emphasized the need to determine the magnitude of the precursor effect for natural compounds

New Trends in Tinnitus Management

Tinnitus is a perception of sound in absence of sound stimulation. Tinnitus in many cases cannot be eliminated by conventional medical treatment with drugs or surgery. Some people who begin to notice tinnitus, whether spontaneous or induced by noise, trauma or other insult, will experience spontaneous resolution, but many patients will have persistent tinnitus. For some of them, tinnitus sensation will be joined by tinnitus suffering, with many adverse effects like anxiety, depression and sleep disorders. For these tinnitus sufferers the psychological and acoustic approach proposed by the Tinnitus Retraining Therapy and Acoustic Desensitization Protocol may be helpful. Periodically new treatments are suggested like low-frequency repetitive transcranial magnetic stimulation and sequential phase shift sound cancellation treatment based on the frequency and loudness matching of the tinnitus. The aim of this work is to review modern considerations for the treatment of tinnitus

El Fútbol en la Educación Física

Dar cuenta de algunos sucesos que la educación física ya sea desde el plano teórico biológico o praxiológico motriz la ubican desde una noción instructiva y tecniscista en el tratamiento del futbol como saber a transmitir, preocupada en hacer lo que le prescribieron y prescriben diferentes teorías científicas articuladas con los ritmos que al proyecto político burgués más le seduzca. El pasaje teórico que la educación física como disciplina fue atravesando siendo que por distintos fenómenos políticos y científicos sucedieron, provocando sus consecuencias en el ámbito del futbol. Poder demostrar por un lado el interés educativo de la educación física con el futbol, desde un modelo que expone al juego como recurso para la estimulación y perfeccionamiento de la motricidad humana, para el desarrollo y el efecto vital y fisiológico, y por el otro métodos de entrenamiento que al ritmo del deporte de mercado no logran romper con un cuerpo dado en su correlato a la intención política de regulación y control de la población, utilizando a modo de ejemplo algunos acontecimientos sucedidos con esta temática en la Argentina y proponiendo un abordaje distinto para con el futbol desde la educación física.Facultad de Humanidades y Ciencias de la Educació