Selected Reaction Monitoring (SRM) frente a Western Blot

We propose the SRM technology as a complementary method to the Western Blot for the detection and quantification of proteins in a sample. The technique Western Blot has its own limitations: i) only a protein-of-choice is detected, ignoring any non-relevant proteins, ii) the sensitivity of the technique depends on the specificity of the antibody and iii) Western Blot is expensive and time-consuming. The advantages of SRM with respect Western Blot are remarkable: i) you can detect up to hundreds of different proteins in a sample, ii) SRM is more sensitive, because just 50 copies of the target protein per cell are enough for the detection and iii) once it has been made an investment in the necessary machinery to develop this technique, the detection of proteins in a sample turns into a cheaper, faster, more specific and full-quantitative procedure, without the need of using antibodies. First of all, SRM requires the identification of little peptides, obtained by tryptic digestion, whose sequence must be unique for a single protein or isoform. There is software for that aim. Then, it’s necessary to create isotope-labeled peptides of that identified for acting as internal standards. That sample is introduced in a triple quadrupole mass spectrometer: it passes through a first quadrupole, which functions as a filter, where the fragments are selected, previously ionized, attending to the mass/charge (m/z) relation that correspond to that unique fragments of the protein of interest. In this first selection may be other peptides from other proteins, with the same m/z but with different sequence. To select those that are exclusive from the target protein, the fragments are moved to a second quadrupole, where they are fragmented again with a physical method, and so new smaller fragments are generated. All the new fragments are conduced to the third quadrupole, where just those which come from the protein of interest are selected, attending at their m/z again. The target peptide concentration is determined by measuring the observed signal response for the target peptide relative to that of the isotopic-labeled peptide, the concentration of which is calculated from a pre-determined calibration-response curve. Calibration curves have to be generated for each target peptide in the sample. Because SRM technology is increasing its use, there have been developed databases where the scientific community upload information about protocols and standards for each protein with the aim to facilitate the work to other researchers

Effectiveness of conventional drinking water treatment in the removal of polycyclic aromatic hydrocarbons

The presence of recalcitrant organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs) in aquatic environments poses a threat to the human health. According to recent studies, PAHs, such as benz[a]anthracene and phenanthrene, has been found in untreated drinking water. Hence, the removal of these contaminants through conventional treatment processes should be carefully evaluated. In this work, levels of selected PAHs in drinking water have been monitored during conventional treatment processes. The simulation of a full-scale Potable Water Treatment Plant (PWTP) located in the south of Spain was carried out using jar tests, a widely accepted tool in water treatment. The quantification of PAH concentration in drinking waterwas carried out using gas chromatography coupled with mass spectrometry.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Removal of polycyclic aromatic hydrocarbons (PAHs) in conventional drinking water treatment processes

Authors acknowledge the Central Laboratory of EMASA for the facilities provided to carry out the research. M. Villen-Guzman acknowledges the postdoctoral fellowship obtained from Universidad de Malaga, Spain. Funding for open access charge: Universidad de Malaga / CBUA, Spain.The presence of polycyclic aromatic hydrocarbons (PAHs) in water poses a serious threat to the human health due to their toxic effects. Therefore, the removal of these compounds from drinking water in Potable Water Treatment Plants (PWTPs) should be evaluated and optimized to assure the quality of water intended for human consumption. In this work, changes in PAHs levels during drinking water treatment processes have been monitored to evaluate the effectiveness of conventional processes in the removal of these recalcitrant pollutants. Several chemical treatment methods based on the addition of KMnO4, FeCl3 and NaClO were evaluated through jar tests. The analysis of PAH content of aqueous samples was carried out by gas chromatography coupled with mass spectrometry. The highest removal efficiency, over 90%, was obtained for benzo(a)anthracene, benzo(a) pyrene and dibenzo(a,h)anthracene. The most recalcitrant compounds to degradation were fluorene, anthracene, phenanthrene and flouranthene with reduction rates between 45 and 57%. The conventional treatment processes assessed have been proved to be effective reducing the PAH below the legal limits of drinking water quality. The definition of a parameter based on chemical properties of PAHs, i.e., sorption capacity and energy required to remove an electron, enabled the prediction of removal rate of pollutants which represents a valuable information for the plant operation.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Ibero-American Society of Interventionism (SIDI) and the Spanish Society of Vascular and Interventional Radiology (SERVEI) Standard of Practice (SOP) for the Management of Inferior Vena Cava Filters in the Treatment of Acute Venous Thromboembolism

Vena cava filtersFiltres de vena cavaFiltros de vena cavaObjectives: to present an interventional radiology standard of practice on the use of inferior vena cava filters (IVCFs) in patients with or at risk to develop venous thromboembolism (VTE) from the Iberoamerican Interventional Society (SIDI) and Spanish Vascular and Interventional Radiology Society (SERVEI). Methods: a group of twenty-two interventional radiologist experts, from the SIDI and SERVEI societies, attended online meetings to develop a current clinical practice guideline on the proper indication for the placement and retrieval of IVCFs. A broad review was undertaken to determine the participation of interventional radiologists in the current guidelines and a consensus on inferior vena cava filters. Twenty-two experts from both societies worked on a common draft and received a questionnaire where they had to assess, for IVCF placement, the absolute, relative, and prophylactic indications. The experts voted on the different indications and reasoned their decision. Results: a total of two-hundred-thirty-three articles were reviewed. Interventional radiologists participated in the development of just two of the eight guidelines. The threshold for inclusion was 100% agreement. Three absolute and four relative indications for the IVCF placement were identified. No indications for the prophylactic filter placement reached the threshold. Conclusion: interventional radiologists are highly involved in the management of IVCFs but have limited participation in the development of multidisciplinary clinical practice guidelines

Continuous renal replacement therapy in children after cardiac surgery

ObjectiveThe objective was to study the clinical course of children requiring continuous renal replacement therapy (CRRT) after cardiac surgery and to analyze the factors associated with mortality.MethodsA prospective observational study was performed that included all children requiring CRRT after cardiac surgery, comparing these patients with other critically ill children requiring CRRT. Univariate and multivariate analyses were performed to determine the influence of each factor on mortality.ResultsEighty-one (4.9%) of 1650 children undergoing cardiac surgery required CRRT; 65 of them (80.2%) presented multiorgan failure. Children starting CRRT after cardiac surgery had lower mean arterial pressure and lower urea and creatinine levels, and were more likely to require mechanical ventilation than other children on CRRT. The incidence of complications was similar. Cardiac surgery increased the probability of requiring CRRT for more than 14 days. Mortality was 43% in children receiving CRRT after cardiac surgery and 29% in other children (P = .05). Factors associated with mortality in the univariate analysis were age less than 12 months, weight less than 10 kg, higher Pediatric Risk of Mortality Score, hypotension, lower urea and creatinine on starting CRRT, and use of hemofiltration. In the multivariate analysis, the only factor associated with mortality was hypotension on starting CRRT (hazard ratio, 4.01; 95% confidence interval, 1.2-13.4; P = .024).ConclusionsAlthough only a small percentage of children undergoing cardiac surgery required CRRT, mortality in these patients was high. Hypotension at the time of starting the technique was the only factor associated with a higher mortality

Leptin alters somatosensory thalamic networks by decreasing gaba release from reticular thalamic nucleus and action potential frequency at ventrobasal neurons

Leptin is an adipose-derived hormone that controls appetite and energy expenditure. Leptin receptors are expressed on extra-hypothalamic ventrobasal (VB) and reticular thalamic (RTN) nuclei from embryonic stages. Here, we studied the effects of pressure-puff, local application of leptin on both synaptic transmission and action potential properties of thalamic neurons in thalamocortical slices. We used whole-cell patch-clamp recordings of thalamocortical VB neurons from wild-type (WT) and leptin-deficient obese (ob/ob) mice. We observed differences in VB neurons action potentials and synaptic currents kinetics when comparing WT vs. ob/ob. Leptin reduced GABA release onto VB neurons throughout the activation of a JAK2-dependent pathway, without affecting excitatory glutamate transmission. We observed a rapid and reversible reduction by leptin of the number of action potentials of VB neurons via the activation of large conductance Ca 2+ -dependent potassium channels. These leptin effects were observed in thalamocortical slices from up to 5-week-old WT but not in leptin-deficient obese mice. Results described here suggest the existence of a leptin-mediated trophic modulation of thalamocortical excitability during postnatal development. These findings could contribute to a better understanding of leptin within the thalamocortical system and sleep deficits in obesity.Fil: Perissinotti, Paula Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Rivero Echeto, Maria Celeste Solange. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Garcia Rill, Edgar. University of Arkansas for Medical Sciences; Estados UnidosFil: Bisagno, Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Urbano Suarez, Francisco Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentin

Effectiveness, retrievability, and safety of celect vs. ALN inferior vena cava filters: a randomized prospective multicenter controlled study

The purpose of this study is to compare IVC Celect and ALN filters in regard to their efficacy, retrievability, and one-year follow-up after retrieval. Materials and Methods: This is a prospective randomized study, conducted in three centers between April 2020 and May 2021. A total of 115 participants were randomized, of which 15 participants were excluded for various reasons. Each group of 50 participants was finally assigned a type of filter (Celect n = 50 and ALN = 50). Tilt angles at placement and retrieval, rates of overall filter retrieval, complications, complex retrieval, and clinical follow-up at 12 months were compared. Results: One hundred participants (59 men and 41 women) were included. The mean age was 62.4 ± 13.3, with no significant differences between both groups (p 0.503). The mean of dwelling time was 44.7 ± 93 days. (p 0.520) Filter retrieval was successful in all participants (100%). The main complication in CT prior to removal was tilt >15° (31%) and filter tip embedment (16%). No significant differences were observed in the type of retrieval (standard or complex) between both filters (p 0.24); however, fluoroscopy time was significantly longer in the complex removal of the Celect filter: 29.1 ± 12 min vs. 17.5 ± 10.3 (p 0.005). After one year, no recurrent pulmonary embolism was observed in both types of filters. Conclusions: The ALN filter had a significantly lower rate of tip and filter tip embedding, with no differences in complexity or removal success rate. There were significant differences in the fluoroscopy time consumed for standard and complex retrievals between both filters, with less time for the ALN filter

Comparação do ultrassom transvaginal e da histeroscopia ambulatorial no diagnóstico das doenças endometriais em mulheres menopausadas

OBJETIVO: Comparar a eficácia do ultrassom transvaginal e da histeroscopia diagnóstica ambulatorial no diagnóstico das doenças intrauterinas em mulheres menopausadas. MÉTODOS: Foram selecionadas 243 mulheres menopausadas que se submeteram a uma histeroscopia diagnóstica no ano de 2006. Todas essas mulheres vieram encaminhadas da rede básica de saúde após terem realizado um ultrassom transvaginal para avaliar a cavidade endometrial. RESULTADOS: As mulheres tinham em média 61±9,4 anos e encontravam-se na menopausa em média há 11±8,3 anos. Observamos 6,6% de casos de hiperplasia endometrial e câncer de endométrio. O ultrassom apresentou uma sensibilidade de 95,6%, uma especificidade de 7,4%, um valor preditivo positivo de 53,3% e valor preditivo negativo de 60%, enquanto a histeroscopia apresentou 95,7%; 83%; 82,2% e 95,9%, respectivamente. CONCLUSÃO: A histeroscopia apresentou maior acurácia que o ultrassom no diagnóstico das doenças endometriais.OBJECTIVE: To compare the efficiency of transvaginal sonography and outpatient hysteroscopy in the diagnosis of intrauterine pathology in postmenopausal women. METHODS: Two-hundred and forty-three postmenopausal women were selected. All women had undergone outpatient hysteroscopy in the year 2006. These women were referred from the Basic Healthcare Units in Campinas, where they underwent ultrasonography for the evaluation of the endometrial cavity. RESULTS: The mean age of these women was 61±9.4 years. These women were menopausal for 11±8.3 years.. We observed 6.6% cases of endometrial hyperplasia and cancer. The ultrasonography had a sensitivy of 95.6%, a specificity of 7.4%, a positive predictive value of 53.3% and a negative predictive value of 60%, while the hysteroscopy had 95.7%, 83%, 82.2% and 95.9% respectively. CONCLUSION: Hysteroscopy was a more accurate method for the detection of intrauterine pathology than ultrasonography