A new algorithm for particle weighted subtraction to decrease signals from unwanted components in single particle analysis.

Single particle analysis (SPA) in cryo-electron microscopy (cryo-EM) is highly used to obtain the near-atomic structure of biological macromolecules. The current methods allow users to produce high-resolution maps from many samples. However, there are still challenging cases that require extra processing to obtain high resolution. This is the case when the macromolecule of the sample is composed of different components and we want to focus just on one of them. For example, if the macromolecule is composed of several flexible subunits and we are interested in a specific one, if it is embedded in a viral capsid environment, or if it has additional components to stabilize it, such as nanodiscs. The signal from these components, which in principle we are not interested in, can be removed from the particles using a projection subtraction method. Currently, there are two projection subtraction methods used in practice and both have some limitations. In fact, after evaluating their results, we consider that the problem is still open to new solutions, as they do not fully remove the signal of the components that are not of interest. Our aim is to develop a new and more precise projection subtraction method, improving the performance of state-of-the-art methods. We tested our algorithm with data from public databases and an in-house data set. In this work, we show that the performance of our algorithm improves the results obtained by others, including the localization of small ligands, such as drugs, whose binding location is unknown a priori.

Local defocus estimation in single particle analysis in cryo-electron microscopy.

Single Particle analysis (SPA) aims to determine the three-dimensional structure of proteins and macromolecular complexes. The current state of the art has allowed us to achieve near-atomic and even atomic resolutions. To obtain high-resolution structures, a set of well-defined image processing steps is required. A critical one is the estimation of the Contrast Transfer Function (CTF), which considers the sample defocus and aberrations of the microscope. Defocus is usually globally estimated; in this case, it is the same for all the particles in each micrograph. But proteins are ice-embedded at different heights, suggesting that defocus should be measured in a local (per particle) manner. There are four state-of-the-art programs to estimate local defocus (Gctf, Relion, CryoSPARC, and Xmipp). In this work, we have compared the results of these software packages to check whether the resolution improves. We have used the Scipion framework and developed a specific program to analyze local defocus. The results produced by different programs do not show a clear consensus using the current test datasets in this study.

In vitro assessment of the combined effect of letermovir and sirolimus on cytomegalovirus replication.

OBJECTIVE: Letermovir (LMV) is used for prophylaxis of cytomegalovirus (CMV) reactivation and end-organ disease in adult CMV-seropositive allogeneic hematopoietic stem cell transplant recipients (allo-HSCT). In turn, sirolimus (SLM) which displays in vitro anti-CMV activity, is frequently employed for prophylaxis of Graft vs. Host disease in allo-HSCT. Here, we aimed at assessing whether LMV and SLM used in combination may act synergistically in vitro on inhibiting CMV replication. METHODS: The antiviral activity of LMV and SLM alone or in combination was evaluated by a checkerboard assay, using ARPE-19 cells infected with CMV strain BADrUL131-Y. LMV and SLM were used at concentrations ranging from 24 nM to 0.38 nM and 16 nM to 0.06 nM, respectively. RESULTS: The mean EC50 for LMV and SLM was 2.44 nM (95% CI, 1.66-3.60) and 1.40 nM (95% CI, 0.41-4.74), respective. LMV and SLM interaction yielded mainly additive effects over the range of concentrations tested. CONCLUSIONS: The additive nature of the combination of LMV and SLM against CMV may have relevant clinical implications in management of CMV infection in allo-HSCT recipients undergoing prophylaxis with LMV.

Ligation of intersphincteric fistula tract (LIFT) for the treatment of anal fistula: a prospective observational study

Background: The ligation of intersphincteric fistula fract (LIFT) technique avoids postoperative anal continence disturbances and preserves quality of life. Methods: A total of 70 patients with anal fistula (AF) were treated in the Day Surgery Unit. The LIFT technique was the primary treatment in 63 patients. The other had previously undergone placement of a loose seton (two-step approach). The mean follow-up was 66.8 months. Statistical analysis was performed using contingency tables, the chi-square test, and the Student T-test. Results: The use of LIFT was successful in 40 patients (57.1%). However, 6 patients (8.6%) presented persistence of postoperative intersphincteric fistula, being successfully treated by fistulotomy. There were no differences in this technique's success rate between high and low AF (p = 0.45). The success rate of one-step LIFT, however, was significantly higher (p = 0.03). No disturbances of continence were observed. Conclusions: The LIFT technique has a role in the treatment of AF, is suitable for ambulatory surgery, and has a low complications rate. A two-step approach is not always needed. (AU)

Cost analysis of the enhanced recovery after surgery protocol applied in advanced ovarian cancer: A secondary outcome of the PROFAST trial.

INTRODUCTION: A randomised trial implementing Enhanced Recovery After Surgery (ERAS) for high complexity advanced ovarian cancer (AOC) surgery (PROFAST) demonstrated a reduction of median length of stay and hospital readmissions when compared to patients managed conventionally. One secondary objective was to determine if an ERAS pathway in the perioperative management of advanced ovarian cancer patients led to cost savings. MATERIAL AND METHODS: Secondary objective of a prospective randomised trial of patients with suspected or diagnosed advanced ovarian cancer allocated to conventional or ERAS perioperative management, carried out at a referral centre from June 2014 to March 2018. Treatment was determined by a computer-generated random allocation system. METHODS: Gross counting was employed to estimate the cost of hospitalisation in wards, intensive care unit (ICU) and surgical care, while micro-costing was used to obtain image and laboratory test costs. Mean costs between trial arms were considered. Sensitivity analyses were performed. RESULTS: Ninety-nine patients (n = 50 ERAS group, n = 49 Conventional group) were included. Mean costs per patient were 10,719€ in the ERAS group and 11,028€ in the conventional group, leading to an average saving of 309€ per patient. These results were based on 96 patients, excluding 3 extreme outliers mainly related with very high ICU costs. Savings, which were significant for hospital ward costs (-33% total; 759€ per patient in first hospitalisation, and 914€ per partient/day of readmission) were found as robust in the sensitivity analysis. CONCLUSIONS: Implementation of an ERAS pathway leads to cost savings when compared to conventional management after AOC surgery.

Image processing tools for the validation of CryoEM maps.

The number of maps deposited in public databases (Electron Microscopy Data Bank, EMDB) determined by cryo-electron microscopy has quickly grown in recent years. With this rapid growth, it is critical to guarantee their quality. So far, map validation has primarily focused on the agreement between maps and models. From the image processing perspective, the validation has been mostly restricted to using two half-maps and the measurement of their internal consistency. In this article, we suggest that map validation can be taken much further from the point of view of image processing if 2D classes, particles, angles, coordinates, defoci, and micrographs are also provided. We present a progressive validation scheme that qualifies a result validation status from 0 to 5 and offers three optional qualifiers (A, W, and O) that can be added. The simplest validation state is 0, while the most complete would be 5AWO. This scheme has been implemented in a website https://biocomp.cnb.csic.es/EMValidationService/ to which reconstructed maps and their ESI can be uploaded.

ScipionTomo: Towards cryo-electron tomography software integration, reproducibility, and validation.

Image processing in cryogenic electron tomography (cryoET) is currently at a similar state as Single Particle Analysis (SPA) in cryogenic electron microscopy (cryoEM) was a few years ago. Its data processing workflows are far from being well defined and the user experience is still not smooth. Moreover, file formats of different software packages and their associated metadata are not standardized, mainly since different packages are developed by different groups, focusing on different steps of the data processing pipeline. The Scipion framework, originally developed for SPA (de la Rosa-Trevín et al., 2016), has a generic python workflow engine that gives it the versatility to be extended to other fields, as demonstrated for model building (Martínez et al., 2020). In this article, we provide an extension of Scipion based on a set of tomography plugins (referred to as ScipionTomo hereafter), with a similar purpose: to allow users to be focused on the data processing and analysis instead of having to deal with multiple software installation issues and the inconvenience of switching from one to another, converting metadata files, managing possible incompatibilities, scripting (writing a simple program in a language that the computer must convert to machine language each time the program is run), etcetera. Additionally, having all the software available in an integrated platform allows comparing the results of different algorithms trying to solve the same problem. In this way, the commonalities and differences between estimated parameters shed light on which results can be more trusted than others. ScipionTomo is developed by a collaborative multidisciplinary team composed of Scipion team engineers, structural biologists, and in some cases, the developers whose software packages have been integrated. It is open to anyone in the field willing to contribute to this project. The result is a framework extension that combines the acquired knowledge of Scipion developers in close collaboration with third-party developers, and the on-demand design of functionalities requested by beta testers applying this solution to actual biological problems.

On bias, variance, overfitting, gold standard and consensus in single-particle analysis by cryo-electron microscopy.

Cryo-electron microscopy (cryoEM) has become a well established technique to elucidate the 3D structures of biological macromolecules. Projection images from thousands of macromolecules that are assumed to be structurally identical are combined into a single 3D map representing the Coulomb potential of the macromolecule under study. This article discusses possible caveats along the image-processing path and how to avoid them to obtain a reliable 3D structure. Some of these problems are very well known in the community. These may be referred to as sample-related (such as specimen denaturation at interfaces or non-uniform projection geometry leading to underrepresented projection directions). The rest are related to the algorithms used. While some have been discussed in depth in the literature, such as the use of an incorrect initial volume, others have received much less attention. However, they are fundamental in any data-analysis approach. Chiefly among them, instabilities in estimating many of the key parameters that are required for a correct 3D reconstruction that occur all along the processing workflow are referred to, which may significantly affect the reliability of the whole process. In the field, the term overfitting has been coined to refer to some particular kinds of artifacts. It is argued that overfitting is a statistical bias in key parameter-estimation steps in the 3D reconstruction process, including intrinsic algorithmic bias. It is also shown that common tools (Fourier shell correlation) and strategies (gold standard) that are normally used to detect or prevent overfitting do not fully protect against it. Alternatively, it is proposed that detecting the bias that leads to overfitting is much easier when addressed at the level of parameter estimation, rather than detecting it once the particle images have been combined into a 3D map. Comparing the results from multiple algorithms (or at least, independent executions of the same algorithm) can detect parameter bias. These multiple executions could then be averaged to give a lower variance estimate of the underlying parameters.

Cryo-EM density maps adjustment for subtraction, consensus and sharpening.

Electron cryomicroscopy (cryo-EM) has emerged as a powerful structural biology instrument to solve near-atomic three-dimensional structures. Despite the fast growth in the number of density maps generated from cryo-EM data, comparison tools among these reconstructions are still lacking. Current proposals to compare cryo-EM data derived volumes perform map subtraction based on adjustment of each volume grey level to the same scale. We present here a more sophisticated way of adjusting the volumes before comparing, which implies adjustment of grey level scale and spectrum energy, but keeping phases intact inside a mask and imposing the results to be strictly positive. The adjustment that we propose leaves the volumes in the same numeric frame, allowing to perform operations among the adjusted volumes in a more reliable way. This adjustment can be a preliminary step for several applications such as comparison through subtraction, map sharpening, or combination of volumes through a consensus that selects the best resolved parts of each input map. Our development might also be used as a sharpening method using an atomic model as a reference. We illustrate the applicability of this algorithm with the reconstructions derived of several experimental examples. This algorithm is implemented in Xmipp software package and its applications are user-friendly accessible through the cryo-EM image processing framework Scipion.

Cryo-EM and Single-Particle Analysis with Scipion.

Cryo-electron microscopy has become one of the most important tools in biological research to reveal the structural information of macromolecules at near-atomic resolution. In single-particle analysis, the vitrified sample is imaged by an electron beam and the detectors at the end of the microscope column produce movies of that sample. These movies contain thousands of images of identical particles in random orientations. The data need to go through an image processing workflow with multiple steps to obtain the final 3D reconstructed volume. The goal of the image processing workflow is to identify the acquisition parameters to be able to reconstruct the specimen under study. Scipion provides all the tools to create this workflow using several image processing packages in an integrative framework, also allowing the traceability of the results. In this article the whole image processing workflow in Scipion is presented and discussed with data coming from a real test case, giving all the details necessary to go from the movies obtained by the microscope to a high resolution final 3D reconstruction. Also, the power of using consensus tools that allow combining methods, and confirming results along every step of the workflow, improving the accuracy of the obtained results, is discussed.

Algorithmic robustness to preferred orientations in single particle analysis by CryoEM.

The presence of preferred orientations in single particle analysis (SPA) by cryo-Electron Microscopy (cryoEM) is currently one of the hurdles preventing many structural analyses from yielding high-resolution structures. Although the existence of preferred orientations is mostly related to the grid preparation, in this technical note, we show that some image processing algorithms used for angular assignment and three-dimensional (3D) reconstruction are more robust than others to these detrimental conditions. We exemplify this argument with three different data sets in which the presence of preferred orientations hindered achieving a 3D reconstruction without artifacts or, even worse, a 3D reconstruction could never be achieved.

Granuloma Anular diseminado: a propósito de un caso / Disseminated annular granuloma: on the purpose of a case

RESUMEN El granuloma anular es un trastorno relativamente frecuente, se desconoce la prevalencia exacta, tiene mayor frecuencia en niños y adultos jóvenes. Se caracteriza por pequeñas pápulas agrupadas, en configuración anular, a menudo con distribución simétrica y acra. La mayor parte los casos se resuelve en forma espontánea dentro de los 2 años, pero la tasa de recidivas es del 40%. Presentamos el caso clínico de una paciente de 72 años de edad con granuloma anular diseminado, tratado con pentoxifilina, con buen resultado terapéutico.

ABSTRACT Annular granuloma is a relatively frequent disorder, the exact prevalence is unknown, it is more frequent in children and young adults. It is characterized by small grouped papules, in annular configuration, often with symmetric and acrid distribution. Most cases resolve spontaneously within 2 years, but the recurrence rate is 40%. We present the clinical case of a 72-year-old patient with disseminated annular granuloma, treated with pentoxifylline, with good therapeutic results.

Improvements on marker-free images alignment for electron tomography.

Electron tomography is a technique to obtain three-dimensional structural information of samples. However, the technique is limited by shifts occurring during acquisition that need to be corrected before the reconstruction process. In 2009, we proposed an approach for post-acquisition alignment of tilt series images. This approach was marker-free, based on patch tracking and integrated in free software. Here, we present improvements to the method to make it more reliable, stable and accurate. In addition, we modified the image formation model underlying the alignment procedure to include different deformations occurring during acquisition. We propose a new way to correct these computed deformations to obtain reconstructions with reduced artifacts. The new approach has demonstrated to improve the quality of the final 3D reconstruction, giving access to better defined structures for different transmission electron tomography methods: resin embedded STEM-tomography and cryo-TEM tomography. The method is freely available in TomoJ software.

Análisis del gasto de bolsillo ante la enfermedad de menores de 5 años según su condición de pobreza en Paraguay / Analysis of out-of-pocket expenses in the face of the disease of children under 5 according to their poverty status in Paraguay

Introducción: Reducir la pobreza, reducir la mortalidad de menores de 5 años (< 5 años) y lograr cobertura universal de salud son parte de los Objetivos de Desarrollo Sostenible (ODS). Objetivo: determinar el gasto de bolsillo de salud (GBS) ante la enfermedad de < 5 años y su inci-dencia económica en los hogares según su condición de pobreza en Paraguay. Material y Método: se analizó la Encuesta Permanente de Hogares del 2014, considerando la defi-nición oficial de pobreza y la referencia de enfermedad o accidente en un trimestre. Se calculó el promedio de GBS por hogar, la incidencia sobre el ingreso monetario trimestral (IM), sobre los sub-sidios estatales por pobreza (IS) y el equivalente de subsistencia o alimentación (EA). Resultados: Entre los hogares no pobres: 41,1% (IC 37,3 a 45,0) tuvo al menos 1 enfermo < 5 años, de los cuales 76,6% (IC 71,5 a 81,0) tuvo GBS, siendo en promedio 223.455 Gs. (DE 37.445). Los medicamentos fueron 68,9% (IC 61,7 a 76,1) del total. La IM fue 1,7% (IC 1,1 a 2,3). Entre los ho-gares pobres: 50,0% (IC 44,7 a 52,2) tuvo al menos 1 enfermo < 5 años, de los cuales 71,2% (IC 64,7 a 76,9) tuvo GBS, siendo en promedio 125.545 Gs. (DE 14.749). Los medicamentos fueron 77,5% (IC 69,2 a 85,7) del total. La IM fue 4,0% (IC 2,3 a 5,8). La IS fue 54,6% (IC 13,0 a 96,2) y el EA fue el equivalente a 7 días de alimentación en promedio (DE 1,5). Conclusión: Ante los retos de los ODS, Paraguay requiere de mayor protección financiera en salud para niñas y niños < 5 años, mediante sinergias de las políticas de reducción de pobreza y de salud. Palabras Clave: gasto de bolsillo de salud, cobertura universal de salud, derecho a la salud, pobreza, menores de 5 años.

Introduction: Reducing poverty, reducing the mortality of children under 5 years (<5 years) and achieving universal health coverage are part of the Sustainable Development Goals (SDGs). Objective: to determine the out-of-pocket health expenditure (GBS) for the disease of <5 years and its economic impact on households according to their poverty status in Para-guay. Material and Method: the 2014 Permanent Household Survey was analyzed, considering the official definition of poverty and the reference of illness or accident in a quarter. The average of GBS per household, the incidence on quarterly monetary income (IM), on state subsidies for poverty (IS) and the equivalent of feeding (EA) were calculated. Results: Among non-poor households: 41.1% (CI 37.3 to 45.0) had at least 1 <5 years ill or injured, of which 76.6% (CI 71.5 to 81.0) had GBS , being on average 223,455 Gs. (DE 37,445). The medications were 68.9% (CI 61.7 to 76.1) of the total. The IM was 1.7% (CI 1.1 to 2.3). Among poor households: 50.0% (CI 44.7 to 52.2) had at least 1 <5 years ill or injured, of which 71.2% (CI 64.7 to 76.9) had GBS, being in average 125,545 Gs. (DE 14,749). The medications were 77.5% (CI 69.2 to 85.7) of the total. The IM was 4.0% (CI 2.3 to 5.8). The IS was 54,6% (IC 13,0 a 96,2) and the EA was the equivalent of 7 days of feeding on av-erage (SD 1.5). Conclusion: Given the challenges of the SDGs, Paraguay requires greater financial protection in health for children under 5 years, through synergies of poverty reduction and health policies. Keywords: out-of-pocket health expenditure, universal health coverage, right to health, pov-erty, children under 5 years.

Integration of Cryo-EM Model Building Software in Scipion.

Advances in cryo-electron microscopy (cryo-EM) have made it possible to obtain structures of large biological macromolecules at near-atomic resolution. This "resolution revolution" has encouraged the use and development of modeling tools able to produce high-quality atomic models from cryo-EM density maps. Unfortunately, many practical problems appear when combining different packages in the same processing workflow, which make difficult the use of these tools by non-experts and, therefore, reduce their utility. We present here a major extension of the image processing framework Scipion that provides inter-package integration in the model building area and full tracking of the complete workflow, from image processing to structure validation.

Quantitative analysis of vitamin D and its main metabolites in human milk by supercritical fluid chromatography coupled to tandem mass spectrometry.

A novel method to quantitate vitamin D and its main metabolites (vitamin D3, vitamin D2, and their 25-hydroxy metabolites) in breast milk by supercritical fluid chromatography has been developed and fully validated. A small volume of sample (1 mL) is subjected to ethanolic protein precipitation and liquid-liquid extraction. Final extracts are derivatized with 4-phenyl-1,2,4-triazoline-3,5-dione and vitamin D derivatives analyzed by supercritical fluid chromatography hyphenated to tandem mass spectrometry with atmospheric pressure chemical ionization. Multiple reaction monitoring is used for quantitation. Separation conditions were optimized using a gradient of methanol-water-ammonium formate into carbon dioxide. Make-up solvent was methanol containing ammonium formate. The quantitation limit reached levels as low as 50 pmol/L, with intra- and inter-day relative standard deviations lower than 15% and 20% for all analytes. Accuracy was evaluated by spiking experiments and was well within acceptability ratios (± 15%). The method was then applied to a subset of commercially available human milk samples. The newly developed method provides opportunities to determine the nutritional status of mother-infant dyads from a non-invasive measure, or for interventional or observational studies building knowledge on the composition of human milk. Graphical abstract.

Análisis del gasto de bolsillo ante la enfermedad de personas de 60 y más años según su condición de pobreza en Paraguay

Introducción: Reducir la pobreza y lograr cobertura universal de salud con protección financiera para las personas de todas las edades son parte de los Objetivos de Desarrollo Sostenible. Objetivo: Determinar el gasto de bolsillo de salud (GBS) ante la enfermedad de personas de 60 y más años (≥ 60 años) y su incidencia económica en los hogares según su condición de pobreza en Paraguay. Material y Método: Se analizó la Encuesta Permanente de Hogares del 2014, considerando la definición oficial de pobreza y la referencia de enfermedad o accidente en un trimestre. Se calculó el promedio de GBS por hogar, la incidencia sobre el ingreso monetario trimestral (IM) y sobre los subsidios estatales por pensión alimentaria para adultos mayores (IPa). Resultados: De los 1.621.525 hogares del país 435.448 tenía al menos 1 persona ≥ 60 años, de los cuales 188.715 tenía al menos 1 de ellos enfermo o accidentado y 144.554 reportó GBS. Entre los hogares no pobres: 11,6% (IC 10,5 a 12,9) tuvo al menos 1 enfermo ≥ 60 años, de los cuales 75,8% (IC 71,2 a 79,8) tuvo GBS, siendo en promedio 547.931 Gs. (DE 58.251). Los medicamentos fueron 53,3% (IC 45,2 a 61,5) del total. La IM fue 5,7% (IC 4,6 a 6,9). Entre los hogares pobres: 11,6% (IC 9,6 a 14,0) tuvo al menos 1 enfermo ≥ 60 años, de los cuales 79,5% (IC 70,7 a 86,2) tuvo GBS, siendo en promedio 341.542 Gs. (DE 49.101). Los medicamentos fueron 71,3% (IC 61,9 a 80,7) del total. La IM fue 11,5% (IC 7,0 a 16,0), la IPa fue de 16,9% (IC 4,4 a 29,4). El GBS fue el equivalente a 19 días de alimentación en promedio (DE 3,71). Conclusión: Paraguay requiere de mayor protección financiera para adultos mayores mediante sinergias de las políticas de reducción de pobreza y de salud.

Introduction: Reducing poverty and achieving universal health coverage for people of all ages are part of the Sustainable Development Goal. Objective: determine the Out-of-pocket Health Expenditure (GBS) for people 60 and older (≥ 60 years) who are sick and its economic impact on households according to their poverty status in Paraguay. Material and Method: the 2014 Permanent Household Survey was analyzed, considering the official definition of poverty and the reference of illness or accident in a quarter. The average of GBS per household, the impact on quarterly monetary risk (IM) and on state subsidies for food pensions for the elderly (IPa). Results: Of 1,621,525 homes in the country 435,448 had at least 1 person 60 years, of which 188,715 had at least 1 of them ill or injured and 144,554 reported GBS. Among the non-poor households: 11.6% (IC 10.5 to 12.9) had at least 1 ill person ≥ 60 years, of which 75.8% (IC 71.2 to 79.8) had GBS, being on average 547,931 Gs. (DE 58,251). The medications were 53.3% (IC 45.2 to 61.5) from total. There was an IM of 5,7% (IC 4.6 to 6.9). Among the poor households: 11.6% (IC 9.6 to 14.0) had at least 1 ill person ≥ 60 years, of which 79.5% (IC 70.7 to 86,2) had GBS, being on average 341,542 Gs. (DE 40,101). The medications were 71.3 % (IC 61.9 to 80.7) from total. There was an IM of 11.5% (IC 7.0 to 16.0). There was an IPa of 16.9% (IC 4.4 to 29.4). The GBS was the equivalent to 19 days of feeding on average (DE 3.71). Conclusion: Paraguay requires more financial protection for older adults through synergies of poverty reduction and health policies.

Estudio de cohortes comparativo del abordaje Superpath con abordaje convencional posterior en cirugía protésica primaria de cadera no cementada: curva de aprendizaje y resultados a corto plazo / Comparative cohort study of the SuperPath approach and the conventional posterior approach in primary cementless hip replacement surgery

Antecedentes y objetivo: En la actualidad no existe un consenso sobre cuál es el mejor abordaje de cadera para implantar una prótesis. Sin embargo, sí existe una tendencia a reducir al máximo la lesión sobre los tejidos periarticulares, lo cual puede influir en los resultados a corto plazo. El abordaje Superpath permite el acceso a la articulación manteniendo la integridad de los rotadores externos. El objetivo de nuestro estudio fue comparar los resultados a corto plazo del abordaje Superpath con el abordaje convencional posterior. Materiales y métodos: Estudio prospectivo de cohorte de 30 pacientes intervenidos mediante abordaje Superpath pareados por sexo, edad, índice de masa corporal y valoración clínica, con 60 pacientes intervenidos mediante abordaje convencional posterior. La valoración clínica se realizó mediante la escala de Harris, Merle d'Aubigné, Womac para el dolor y la función, SF-12 físico y mental, HOS-AVD e IHOT-12. Radiológicamente se determinó el ángulo de inclinación acetabular, alineación del vástago femoral e integración de los implantes. Resultados: No hubo diferencias significativas entre ambas cohortes con respecto a las variables preoperatorias. El tiempo quirúrgico, el descenso medio de Hb y Hto y la pérdida sanguínea fue mayor en la cohorte Superpath. La estancia hospitalaria fue similar. Los cuestionarios de valoración clínica mostraron incrementos significativos entre los valores preoperatorios y a los 12 meses en ambas cohortes. El cuestionario IHOT-12 a los 3 meses, el cuestionario SF-12 físico y el cuestionario SF-12 mental a los 12 meses, mostró mayores puntuaciones en la cohorte Superpath, siendo las diferencias significativas. Radiológicamente no se detectaron diferencias entre ambas cohortes. Conclusiones: La curva de aprendizaje del abordaje Superpath presenta unos resultados clínicos y radiológicos similares al abordaje posterior durante el primer año tras la prótesis total de cadera. A destacar la necesidad de un mayor tiempo quirúrgico y un mayor sangrado en los pacientes

Background and objectives: There is no current consensus on the most suitable hip approach. However, there is a trend to reduce damage to soft tissue, which may have an influence on early outcomes. The SuperPath approach accesses the capsule maintaining integrity of the external rotators. The purpose of this study was to compare the SuperPath approach with the conventional posterior approach, in terms of early outcomes and radiological results. Material and methods: A cohort of 30 patients operated using the SuperPath approach was prospectively matched for age, gender, body mass index and hip function with 60 patients operated using a conventional posterior approach. Clinical evaluation was performed by the Harris score, Merle d'Aubigné score, reduced Western Ontario and McMasters Universities (WOMAC), Short-Form 12 (SF12), IHOT-ADV and IHOT-12 questionnaires. Radiological evaluation was also performed. Results: Preoperatively, no significant differences were detected between cohorts. Skin-to-skin operation time and blood loss was higher in the SuperPath cohort. Length of stay was similar between cohorts. Clinical evaluation improved significantly from the preoperative values to the 1-year follow-up. At 3 months the SuperPath cohort showed better results for IHOT-12, and at 12 months for SF. Radiologically, there were no differences between cohorts. Conclusion: This prospective randomized study reveals that the learning curve for the SuperPath approach provides similar outcomes to the conventional posterior approach within the first year after surgery. The Superpath approach was associated with longer skin-to-skin operation time, and greater blood loss

A critical retrospective and prospective review of designs and materials in in-line solid-phase extraction capillary electrophoresis.

Several strategies have been developed to decrease the concentration limits of detection (LODs) in capillary electrophoresis (CE). Nowadays, chromatographic-based preconcentration using a microcartridge integrated in the separation capillary for in-line solid-phase extraction capillary electrophoresis (SPE-CE) is one of the best alternatives for high throughput and reproducible sample clean-up and analyte preconcentration. This review covers different designs (geometrical configurations, with frits or fritless, capillary types, compatibility with commercial instrumentation, etc.) and materials (sorbents, supports, affinity ligands, etc.) applied for almost 30 years to prepare in-line SPE-CE microcartridges (i.e. analyte concentrators), with emphasis on the conventional unidirectional configuration in capillary format. Advantages, disadvantages and future perspectives are analyzed in detail to provide the reader a wide overview about the great potential of this technique to enhance sensitivity and address trace analysis.

Comparison of two methods skipping cell lysis and protein extraction for identification of bacteria from blood cultures by matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry.

OBJECTIVE: Matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry (MALDI-TOF MS) is widely used for fast identification of bacteria from blood cultures (BC). We compared the performance of two procedures, one including a pre-enrichment step in brain heart infusion and the other a direct method using vacutainer separator gel tubes (DI), for identification of bacteria from blood cultures by MALDI-TOF MS. METHODS: We first prepared a training set of 20 simulated bacteremia specimens, including 10 Gram-negative and 10 Gram-positive species. A total of 145 non-consecutive BCs flagged as positive (68 Gram-negative rods, and 77 Gram-positive cocci) were prospectively analyzed (validation set). RESULTS: A total of 82% and 49% of isolates were correctly identified to the species level by the respective methods. CONCLUSIONS: The pre-enrichment method outperformed the DI method for identification of virtually all bacterial species included in the panels.