[Effectiveness of tranexamic acid for decreased allogenic blood transfusion in total hip arthroplasty]. / Eficacia del ácido tranexámico para la disminución de la transfusión de sangre alogénica en la artroplastía total de cadera.

INTRODUCTION: ATC can cause considerable blood loss. To reduce the need for blood transfusion, various preoperative techniques such as administration of tranexamic acid (ATX) are used. OBJECTIVE: to demonstrate that the use of ATX decreases the need for allogeneic blood transfusion in patients operated on ATC. MATERIAL AND METHODS: Prospective, observational, descriptive study, used to observe the allogeneic blood transfusion rate in patients who underwent unilateral primary ATC from May 2016 to December 2017. ATX was applied preoperatively and after 24 hours a blood count was taken and the need for blood transfusion was assessed. RESULTS: A total of 70 patients were included in the study. The average postoperative Hb 11.7 mg/dl with a range of 9.2 to 14.9 mg/dl and an average Ht of 37.1% with a range of 30.2 to 44.2%. None of the patients required allogeneic blood transfusión. CONCLUSIONS: This study demonstrates how ATX is a transoperative strategy to reduce the need for allogeneic blood transfusion in patients undergoing primary ATC.

INTRODUCCIÓN: La artroplastía total de cadera (ATC) puede causar una pérdida considerable de sangre. Para reducir la necesidad de transfusión de sangre se utilizan diversas técnicas preoperatorias como la administración de ácido tranexámico (ATX). OBJETIVO: Demostrar que el uso de ATX disminuye la necesidad de transfusión de sangre alogénica en pacientes operados de ATC. MATERIAL Y MÉTODOS: estudio prospectivo, observacional, descriptivo, utilizado para observar la tasa de transfusión de sangre alogénica en pacientes a quienes se les practicó ATC primaria unilateral de Mayo de 2016 a Diciembre de 2017. A los pacientes incluidos en el estudio se les aplicó ATX preoperatoriamente, a las 24 horas se tomó una biometría hemática y se valoró la necesidad de transfusión sanguínea. RESULTADOS: Se incluyó un total de 70 pacientes en el estudio. La Hb promedio postquirúrgica 11.7 mg/dl con un rango de 9.2 a 14.9 mg/dl y un Hto promedio de 37.1% con un rango de 30.2 a 44.2%. Ninguno de los pacientes requirió de transfusión de sangre alogénica. CONCLUSIONES: En este estudio se demuestra cómo el ATX es una estrategia transoperatoria para reducir la necesidad de transfusión de sangre alogénica en pacientes a quienes se realiza una ATC primaria.

Kink far below the Fermi level reveals new electron-magnon scattering channel in Fe.

Many properties of real materials can be modeled using ab initio methods within a single-particle picture. However, for an accurate theoretical treatment of excited states, it is necessary to describe electron-electron correlations including interactions with bosons: phonons, plasmons, or magnons. In this work, by comparing spin- and momentum-resolved photoemission spectroscopy measurements to many-body calculations carried out with a newly developed first-principles method, we show that a kink in the electronic band dispersion of a ferromagnetic material can occur at much deeper binding energies than expected (Eb = 1.5 eV). We demonstrate that the observed spectral signature reflects the formation of a many-body state that includes a photohole bound to a coherent superposition of renormalized spin-flip excitations. The existence of such a many-body state sheds new light on the physics of the electron-magnon interaction which is essential in fields such as spintronics and Fe-based superconductivity.

Alergia alimentaria a maní: conceptos clínicos, diagnósticos y terapéuticos / Food allergy to peanuts: clinical, diagnostic and therapeutic concepts

The prevalence of food allergy (FA) is about 2-8 percent, with clinical manifestations ranging from localized symptoms, to severe anaphylactic reactions. FA is generally caused by milk, eggs, soybeans, tree nuts, peanuts, wheat, fish and crustacean; being peanut one of the main foods involved in Western countries. Although in other parts of the world peanut allergy (PA) is not a problem, probably due to timing of introduction into the diet, form and preparation, genetics, and the hygiene hypothesis. Unfortunately, in Chile there are no epidemiological data about FA or PA. A number of food allergens have been identified, which has improved patient diagnosis and treatment assessment. Regarding peanut, 9 allergens have been identified, Ara h 1 to Ara h 9 (Arachis hypogaea). The diagnosis of IgE-mediated PA is based on a consistent history and evidence of peanut-specific IgE sensitization, carried out by skin-prick testing or in vitro determination. PA treatment consists of peanuts avoidance, which often becomes difficult due to inadvertent consumption. Today promising treatments are under development, including oral induction tolerance or sublingual immunotherapy. These treatments offer the possibility of at least raising the threshold of the amount of peanut that would be necessary to cause a life-threatening allergic reaction.

Rapid assessment of high-dose radiation exposures through scoring of cell-fusion-induced premature chromosome condensation and ring chromosomes.

Analysis of premature chromosome condensation (PCC) mediated by fusion of G0-lymphocytes with mitotic CHO cells in combination with rapid visualization and quantification of rings (PCC-Rf) is proposed as an alternative technique for dose assessment of radiation-exposed individuals. Isolated lymphocytes or whole blood from six individuals were γ-irradiated with 5, 10, 15 and 20Gy at a dose rate of 0.5Gy/min. Following either 8- or 24-h post-exposure incubation of irradiated samples at 37°C, chromosome spreads were prepared by standard PCC cytogenetic procedures. The protocol for PCC fusion proved to be effective at doses as high as 20Gy, enabling the analysis of ring chromosomes and excess PCC fragments. The ring frequencies remained constant during the 8-24-h repair time; the pooled dose relationship between ring frequency (Y) and dose (D) was linear: Y=(0.088±0.005)×D. During the repair time, excess fragments decreased from 0.91 to 0.59 chromatid pieces per Gy, revealing the importance of information about the exact time of exposure for dose assessment on the basis of fragments. Compared with other cytogenetic assays to estimate radiation dose, the PCC-Rf method has the following benefits: a 48-h culture time is not required, allowing a much faster assessment of dose in comparison with conventional scoring of dicentrics and rings in assays for chemically-induced premature chromosome condensation (PCC-Rch), and it allows the analysis of heavily irradiated lymphocytes that are delayed or never reach mitosis, thus avoiding the problem of saturation at high doses. In conclusion, the use of the PCC fusion assay in conjunction with scoring of rings in G0-lymphocytes offers a suitable alternative for fast dose estimation following accidental exposure to high radiation doses.

Within-city contrasts in PM composition and sources and their relationship with nitrogen oxides.

The present work is part of the INMA (INfancia y Medio Ambiente -'Environment and Childhood') project, which aims at assessing the adverse effects of exposure to air pollution during pregnancy and early in life. The present study was performed in the city of Sabadell (Northeast Spain) at three sampling sites covering different traffic characteristics, during two times of the year. It assesses time and spatial variations of PM(2.5) concentrations, chemical components and source contributions, as well as gaseous pollutants. Furthermore, a cross-correlation analysis of PM components and source contributions with gaseous pollutants used as a proxy for exposure assessment is carried out. Our data show the influence of traffic emissions in the Sabadell area. The main PM sources identified by Positive Matrix Factorisation (PMF) were similar between the two seasons: mineral source (traffic-induced resuspension, demolition/construction and natural background), secondary sulphate (higher in summer), secondary nitrate (only during winter), industrial, and road traffic, which was the main contributor to PM(2.5) at two of the sites. The correlation of concentrations of nitrogen oxides was especially strong with those of elemental carbon (EC). The relatively weaker correlations with organic carbon (OC) in summer are attributed to the variable formation of secondary OC. Strong correlations between concentration of nitrogen oxides and PM(2.5) road traffic contributions obtained from source apportionment analysis were seen at all sites. Therefore, under the studied urban environment, nitrogen oxides can be used as a proxy for the exposure to road traffic contribution to PM(2.5); the use of NO(x) concentrations being preferred, with NO and NO(2) as second and third options, respectively.

Biological dosimetry intercomparison exercise: an evaluation of triage and routine mode results by robust methods.

Well-defined protocols and quality management standards are indispensable for biological dosimetry laboratories. Participation in periodic proficiency testing by interlaboratory comparisons is also required. This harmonization is essential if a cooperative network is used to respond to a mass casualty event. Here we present an international intercomparison based on dicentric chromosome analysis for dose assessment performed in the framework of the IAEA Regional Latin American RLA/9/054 Project. The exercise involved 14 laboratories, 8 from Latin America and 6 from Europe. The performance of each laboratory and the reproducibility of the exercise were evaluated using robust methods described in ISO standards. The study was based on the analysis of slides from samples irradiated with 0.75 (DI) and 2.5 Gy (DII). Laboratories were required to score the frequency of dicentrics and convert them to estimated doses, using their own dose-effect curves, after the analysis of 50 or 100 cells (triage mode) and after conventional scoring of 500 cells or 100 dicentrics. In the conntional scoring, at both doses, all reported frequencies were considered as satisfactory, and two reported doses were considered as questionable. The analysis of the data dispersion among the dicentric frequencies and among doses indicated a better reproducibility for estimated doses (15.6% for DI and 8.8% for DII) than for frequencies (24.4% for DI and 11.4% for DII), expressed by the coefficient of variation. In the two triage modes, although robust analysis classified some reported frequencies or doses as unsatisfactory or questionable, all estimated doses were in agreement with the accepted error of ±0.5 Gy. However, at the DI dose and for 50 scored cells, 5 out of the 14 reported confidence intervals that included zero dose and could be interpreted as false negatives. This improved with 100 cells, where only one confidence interval included zero dose. At the DII dose, all estimations fell within ±0.5 Gy of the reference dose interval. The results obtained in this triage exercise indicated that it is better to report doses than frequencies. Overall, in both triage and conventional scoring modes, the laboratory performances were satisfactory for mutual cooperation purposes. These data reinforce the view that collaborative networking in the case of a mass casualty event can be successful.

Etiopatogenia de la esclerosis sistémica progresiva / Etiopathogenesis of systemic sclerosis

La esclerosis sistémica progresiva (ESP) es una enfermedad autoinmune crónica del tejido conectivo. Se caracteriza por una alteración vascular inicial, una respuesta inmune alterada con producción de autoanticuerpos y un exceso de síntesis y depósito de fibras de colágeno en la piel y tejido conectivo. La activación y el daño endotelial son eventos tempranos en la patogenia de la enfermedad; sin embargo, el factor gatillante continúa siendo desconocido. Se piensa que el evento principal sería la interacción entre eventos autoinmunes y cambios vasculares tempranos, lo cual resulta en la generación de fibroblastos activados considerados como las células efectoras de la enfermedad. Se reconocen dos subgrupos clínicos de ESP: la variedad cutánea limitada y la variedad cutánea difusa, las cuales presentan distintos patrones de compromiso orgánico, autoanticuerpos, evolución y sobrevida.

Progressive systemic sclerosis is a chronic autoimmune disease of connective tissue. It is characterized by early vascular changes, altered immune response with production of auto-antibodies, and excessive synthesis and deposition of collagen fibers in the skin and connective tissue. Activation and endothelial cell damage are early events in the pathogenesis of the disease, but the precise triggering event(s) remain elusive. The main event would be the interaction between autoimmune events early vascular changes, resulting in the generation of activated fibroblasts, regarded as effector cells of the disease. There are two major subgroups of SSc, the limited cutaneous and the diffuse cutaneous variety, which have distinct patterns of organ involvement, self-auto-antibodies, evolution and survival.

Donor-specific antibody detection: comparison of single antigen assay and Luminex crossmatches.

Luminex bead-based assays are routinely used in the study of anti-human leukocyte antigen (HLA) donor-specific antibodies (DSA). Single antigen (SA) assays use beads coated with recombinant antigens whereas Luminex crossmatch (Xm-DSA) tests consist of beads coated with isolated donor-specific HLA molecules. The aim of this study was to compare these techniques used to detect DSA. A total of 24 sera recognizing different HLA class I (seven anti-HLA-A and seven anti-HLA-B) as well as class II (seven anti-HLA-DR and three anti-HLA DQ) specificities by complement dependent cytotoxicity were included in the study. These sera were used undiluted and in serial dilutions to perform both class I and II SA and Xm-DSA assays. In the case of Xm-DSA the same serum was checked with different lysates. A total of 42 lysates were used to perform a total of 61 crossmatches: 42 to detect anti-class I and 19 to detect anti-class II antibodies. The maximum positive dilution was higher for SA in 76% of the class I and in 90% of the class II crossmatches. Those cases with a higher sensitivity of the Xm-DSA could not be explained by a larger number of antigen targets.

Association between modelled traffic-related air pollution and asthma score in the ECRHS.

The aim of our analysis was to study the association between air pollution and asthma among adults. For this goal, a previously developed "asthma score" was used. Persons aged 25-44 yrs were randomly selected (1991-1993) and followed up (2000-2002) within the European Community Respiratory Health Survey (ECRHS I and II, respectively). The asthma score was defined from 0 to 5, based on the positive answers to the following symptoms reported for the last 12 months: wheeze/breathlessness, chest tightness, dyspnoea at rest, dyspnoea after exercise and woken by dyspnoea. Participants' home addresses were linked to outdoor modelled NO2 estimates for 2001. Negative binomial regression was used to model the asthma score. The score from ECRHS II was positively associated with NO2 (ratio of the mean asthma score (RMS) 1.23, 95% CI 1.09-1.38, for an increase of 10 microg x m(-3)). After excluding participants with asthma and symptoms at baseline, the association remained (RMS 1.25, 95% CI 1.05-1.51), and was particularly high among those reporting a high score in ECRHS II. The latter probably reflects incident cases of asthma. Our results suggest that traffic-related pollution causes asthma symptoms and possibly asthma incidence in adults. The asthma score offers an alternative with which to investigate the course and aetiology of asthma in adults.

Total serum IgE levels are associated with ambient ozone concentration in asthmatic adults.

BACKGROUND: Effects of air pollution exposure on IgE-mediated response in asthmatics are poorly investigated. The aim was to examine the relationship between air pollution concentrations and total IgE levels in adult asthmatics. METHODS: The present study relates to the 369 asthmatic adults from the French Epidemiological study on Genetics and Environment of Asthma (EGEA), with availability of data on both total serum IgE measurements and air pollution concentrations. Geo-statistical models were performed on 4 x 4 km grids to assess individual outdoor air pollution exposure. Annual outdoor concentrations of ozone (O(3)), nitrogen dioxide (NO(2)), sulphur dioxide (SO(2)), and particulate matter smaller than 10 microm size (PM(10)), and concentrations of summer ozone were assigned to subject's home address. RESULTS: The geometric mean of total IgE was 161 IU/ml and the average of O(3) exposure was 44.9 +/- 9.5 microg/m(3). Ozone concentrations were positively related to total IgE levels and an increase of 10 microg/m(3) of O(3) resulted in an increase of 20.4% (95% CI = 3.0-40.7) in total IgE levels. Adjustment for age, gender, smoking habits and previous life in the countryside did not change the results, and an increase of 19.1% (2.4-38.6) in total IgE was observed with O(3). Negative associations observed between NO(2) and total IgE levels disappeared after including O(3) in the models. Neither SO(2) nor PM(10) were correlated with total IgE levels. CONCLUSIONS: Results suggest that O(3) or related ambient pollutants may up-regulate total IgE levels among asthmatic adults.

Transition-metal-substituted indium thiospinels as novel intermediate-band materials: prediction and understanding of their electronic properties.

Results of density-functional calculations for indium thiospinel semiconductors substituted at octahedral sites with isolated transition metals (M=Ti,V) show an isolated partially filled narrow band containing three t2g-type states per M atom inside the usual semiconductor band gap. Thanks to this electronic structure feature, these materials will allow the absorption of photons with energy below the band gap, in addition to the normal light absorption of a semiconductor. To our knowledge, we demonstrate for the first time the formation of an isolated intermediate electronic band structure through M substitution at octahedral sites in a semiconductor, leading to an enhancement of the absorption coefficient in both infrared and visible ranges of the solar spectrum. This electronic structure feature could be applied for developing a new third-generation photovoltaic cell.

[Short-Stay Medical Unit, an alternative to conventional hospitalization]. / Unidad Médica de Corta Estancia, una alternativa a la hospitalización convencional.

BACKGROUND: The Short-Stay Medical Unit (SSMU) is an alternative to conventional hospitalization. This study has aimed to analyze the evolution of admissions and duration of stay in a SSMU, to outline the characteristics of the patients while studying their relationship to length of time spent in the unit and their destination on discharge as well as to assess how appropriately their cases were resolved. MATERIAL AND METHODS: A descriptive study was carried out (2000-2005), analyzing their age, sex, destination on discharge and main diagnosis as well as the evolution of admissions and length of stay over this period. In order to determine how appropriately each case was resolved, length of stay and destination on discharge were considered. The data were analyzed using the SPSS program. RESULTS: During the study period there was an increase in the number of admissions and in length of stay. The average age of the 7,618 patients was 70.6 +/- 16.9 years and the average stay 2.7 +/- 1.4 days. One of the most frequent diagnoses was chronic obstructive pulmonary disease (COPD) (15.9%). On discharge, 85.9% of patients were sent home. A total of 76.4% of cases were resolved satisfactorily, with significant statistical differences related to age, diagnosis and number of diagnoses. CONCLUSIONS: A progressive increase in admissions and length of stay was observed. Ninety percent of the cases of the younger patients were resolved satisfactorily, this decreasing to 72% for older patients. The number of diagnoses, specific diagnoses and age caused some difficulty in reaching an appropriate resolution.

Association between annoyance and individuals' values of nitrogen dioxide in a European setting.

INTRODUCTION: Annoyance caused by air pollution has been proposed as an indicator of exposure to air pollution. The aim of this study was to assess the geographical homogeneity of the relationship between annoyance and modelled home-based nitrogen dioxide (NO2) measurements. METHODS: The European Community Respiratory Health Survey II was conducted in 2000-1, in 25 European centres in 12 countries. This analysis included 4753 subjects (from 37 in Tartu, Estonia, to 532 in Antwerp, Belgium) who answered the annoyance question and with available outdoor residential NO2 (4399 modelled and 354 measured) including 20 cities from 10 countries. Annoyance as a result of air pollution was self-reported on an 11-point scale (0, no disturbance at all; 10, intolerable disturbance). Demographic and socioeconomic factors, smoking status and the presence of respiratory symptoms or disease were measured through a standard questionnaire. Negative binomial regression was used. RESULTS: The median NO2 concentration was 27 microg.m(-3) (from 10 in Umeå, Sweden, to 57 in Barcelona, Spain). The mean of annoyance was 2.5 (from 0.7 in Reykjavik, Iceland, to 4.4 in Huelva, Spain). NO2 was associated with annoyance (ratio of the mean score 1.26 per 10 microg.m(-3), 95% CI 1.19 to 1.34). The association between NO2 and annoyance was heterogeneous among cities (p for heterogeneity <0.001). CONCLUSIONS: Annoyance is associated with home outdoor air pollution but with a different strength by city. This indicates that annoyance is not a valid surrogate for air pollution exposure. Nevertheless, it may be a useful measure of perceived ambient air quality and could be considered a complementary tool for health surveillance.

User satisfaction and forces generated during laryngoscopy using disposable Miller blades: a manikin study.

Increasing awareness of prion-related diseases has led to an increase in the number of disposable laryngoscope blades available. We compared 11 disposable and standard re-usable Miller size 1 blades. In this manikin-based study, we studied user satisfaction for field of view at laryngoscopy, build quality and users' willingness to use the blade in an emergency situation. These were found to be better with metal disposable blades (p

Characteristics of arsenic adsorption to sorghum biomass.

The development of efficient and economic new adsorbent materials for the removal of arsenic from groundwater is a priority in regions where human health is directly affected by elevated arsenic concentrations. Adsorption of arsenic on sorghum biomass (SB) was investigated for the removal of arsenic from aqueous solutions. Potentiometric titrations and FTIR analysis evidenced two potential binding sites associated with carboxyl and hydroxyl groups. Batch experiments were carried out to determine the equilibrium time for arsenic adsorption to SB. The effect of pH on arsenic adsorption to SB was investigated for a pH range of 2.0-10.0. A strong influence of pH was demonstrated with a maximum removal of arsenic at pH 5.0. Freundlich and Langmuir isotherms were applied to equilibrium data. The Freundlich model fitted the equilibrium data and provided evidence for site heterogeneity at the binding surface. Column experiments were performed to obtain the breakthrough curves for both non-immobilized sorghum biomass and immobilized sorghum biomass.

Chronic bronchitis and urban air pollution in an international study.

OBJECTIVES: The chronic effects of urban air pollution are not well known. The authors' aim was to investigate the association between the prevalence and new onset of chronic bronchitis and urban air pollution. METHODS: Subjects from the general population randomly selected for the European Community Respiratory Health Survey (ECRHS I) during 1991-93 in 21 centres in 10 countries were followed up from the years 2000 to 2002 (n = 3232 males and 3592 females; average response rate = 65.3%). PM2.5 and elements, with the same equipment at centre level, and home outdoor NO2 in 1634 individuals were measured. Hierarchical models were used. RESULTS: The prevalence and new onset of chronic phlegm during follow up were 6.9% and 4.5%, respectively, 5.3% in males and 3.5% in females. Smoking, rhinitis, poor education, and low social class were associated with (prevalence and new onset of) chronic phlegm in both genders, and occupational exposures in males and traffic intensity (adjusted odds ratio for constant traffic, OR = 1.86; 95% CI 1.24 to 2.77) as well as home outdoor NO2 (OR > 50 microg/m3v < 20 microg3 = 2.71; 95% CI 1.03 to 7.16) among females. PM2.5 and S content at centre level did not show any association with prevalence or new onset of chronic phlegm. Similar results were obtained with chronic productive cough. CONCLUSION: Individual markers of traffic at household level such as reported intensity and outdoor NO2 were risk factors for chronic bronchitis among females.

De novo autoimmune hepatitis following liver transplantation for primary biliary cirrhosis.

De novo autoimmune hepatitis (AIH) is a rare disorder first described in 1998. It appears in patients with liver transplants for non-AIH etiology. The few cases in the literature make it a little known entity due to mechanisms that are unclear. We present the case of a woman with a liver transplant whose graft developed de novo AIH. Diagnosed with primary biliary cirrhosis, the patient underwent liver transplantation for refractory pruritus. Sixteen months after transplantation, we detected alterations in the hepatic profile with hypertransaminasemia and elevated alkaline phosphatase, together with elevated antinuclear antibodies. IgG levels were normal. Histological findings indicated AIH. The patient responded rapidly to treatment with prednisolone and azathioprine. De novo AIH in patients transplanted for PBC may cause graft dysfunction. This report also analyzes the case with respect to the other four reported cases, discussing etiologic hypotheses.

Sevoflurane (12% and 8%) inhalational induction in children.

BACKGROUND: Sevoflurane induction of anesthesia is frequently used in children. Rapidly performed inhalational induction may reduce excitation during early anesthesia. Increasing the total anesthetic MAC delivered to patients can be achieved by increasing volatile concentration or adding nitrous oxide. The latter reduces inspired oxygen concentration delivered, which may not be desirable. Even 8% sevoflurane induction is associated with excitation. A system capable of delivering 12% sevoflurane using two tandem vaporizers has been developed. METHODS: A randomized double blind study was undertaken to assess whether 12% sevoflurane offered any advantage over 8% in time and quality of induction. Sixty children aged 5-10 years were recruited and received either 12 or 8% sevoflurane. Time to loss of eyelash reflex, central pupils, incidence of adverse events, induction quality, systolic blood pressure and heart rate were recorded. RESULTS: Twelve percent sevoflurane reduced time to loss of eyelash reflex compared with 8% [mean (sd): 35 (12) and 46 (14) P<0.05], but the reduction was only 10% higher than the error in the measurement (assessment every 10 s). Twelve percent sevoflurane offered significantly better quality of induction (P<0.05). There was no difference in cardiovascular stability between groups, although heart rate rose significantly in both groups. Maintaining sevoflurane at 12% for 4 min caused significant amounts of apnea (69% with 12% and 38% with 8%, P<0.05). CONCLUSION: Twelve percent sevoflurane offers a smoother anesthesia induction than 8% in children of this age with no additional consequences for the cardiovascular system.