Few-seconds range verification with short-lived positron emitters in carbon ion therapy.

In-beam PET (Positron Emission Tomography) is one of the most precise techniques for in-vivo range monitoring in hadron therapy. Our objective was to demonstrate the feasibility of a short irradiation run for range verification before a carbon-ion treatment. To do so a PMMA target was irradiated with a 220 MeV/u carbon-ion beam and annihilation coincidences from short-lived positron emitters were acquired after irradiations lasting 0.6 s. The experiments were performed at the synchrotron-based facility CNAO (Italian National Center of Oncological Hadrontherapy) by using the INSIDE in-beam PET detector. The results show that, with 3·107 carbon ions, the reconstructed positron emitting nuclei distribution is in good agreement with the predictions of a detailed FLUKA Monte Carlo study. Moreover, the radio-nuclei production is sufficiently abundant to determine the average ion beam range with a σ of 1 mm with a 6 s measurement of the activity distribution. Since the data were acquired when the beam was off, the proposed rapid calibration method can be applied to hadron beams extracted from accelerators with very different time structures.

Application of a short-wave pocket-sized near-infrared spectrophotometer to predict milk quality traits.

Portable handheld devices based on near-infrared (NIR) technology have improved and are gaining popularity, even if their implementation in milk has been barely evaluated. Thus, the aim of the present study was to assess the feasibility of using short-wave pocket-sized NIR devices to predict milk quality. A total of 331 individual milk samples from different cow breeds and herds were collected in 2 consecutive days for chemical determination and spectral collection by using 2 pocket-sized NIR spectrophotometers working in the range of 740 to 1,070 nm. The reference data were matched with the corresponding spectrum and modified partial least squares regression models were developed. A 5-fold cross-validation was applied to evaluate individual device performance and an external validation with 25% of the dataset as the validation set was applied for the final models. Results revealed that both devices' absorbance was highly correlated but greater for instrument A than B. Thus, the final models were built by averaging the spectra from both devices for each sample. The fat content prediction model was adequate for quality control with a coefficient of determination (R2ExV) and a residual predictive deviation (RPDExV) in external validation of 0.93 and 3.73, respectively. Protein and casein content as well as fat-to-protein ratio prediction models might be used for a rough screening (R2ExV >0.70; RPDExV >1.73). However, poor prediction models were obtained for all the other traits with an R2ExV between 0.43 (urea) and 0.03 (SCC), and a RPDExV between 1.18 (urea) and 0.22 (SCC). In conclusion, short-wave portable handheld NIR devices accurately predicted milk fat content, and protein, casein, and fat-to-protein ratio might be applied for rough screening. It seems that there is not enough information in this NIR region to develop adequate prediction models for lactose, SCC, urea, and freezing point.

The effects of dietary iodine content, milking system, and farming practices on milk iodine concentration and quality traits.

Various management practices can influence milk quality traits in dairy cattle. As an example, an increasing investment in automatic milking system to substitute milking parlors has been observed in the last 2 decades in dairy farms which could have affected certain bulk milk quality traits. What is more, milking practices can also affect certain milk parameters; as an example, teat disinfectants containing I are used in commercial farms where pre- or postdipping is performed, leading to presence of some I in the bulk milk. However, this trace mineral is also supplied in cows' diet to fulfill their nutritional requirements, partly contributing to the milk I final concentration. Therefore, the aim of this study was to evaluate the sources of variation of milk I along with other traditional milk quality traits. A total of 91 dairy farms in northeastern Italy were enrolled in the study. In each farm, diet and bulk milk samples were collected on the same day for chemical analysis. Concentration of I, in particular, was determined in both milk and feed with gold standard. Pearson correlations were calculated among the traits available for milk and diet, and a general linear model was used to test significance of fixed effects (feeding system, milking system, farming system, herd size, herd stage of lactation, and sampling month) on milk quality traits including the I concentration. In the case of milk I, diet I and presence of I-based predipping and postdipping teat disinfect application were also tested as fixed effects. Results showed a positive linear correlation between milk and diet I content (correlation coefficient [r] = 0.78). Although milk I was also positively correlated with lactose content (r = 0.25), dietary I was not correlated with other milk traits. Milk I content was significantly affected by dietary I, I-based predipping teat disinfectant application, and herd composition. Compared with conventional farms, organic farms showed lower protein content and greater somatic cell score (SCS) but similar milk I. Milking system significantly affected only lactose content and SCS of milk. Sampling month was only significant for milk urea nitrogen and herd composition, feeding system, herd size, and herd average days in milk did not modify milk gross composition and SCS. In conclusion, dietary supply of I is the main factor affecting milk I concentration and findings suggest that I level in milk can be naturally improved in dairy cows by modulating the I content in the diet administered. However, further research is needed to evaluate the effect of I-based sanitizers on milk I.

¿Debemos manejar la hiperuricemia asintomática para proteger al riñón?

Contexto: el ácido úrico es el producto final de la degradación de las purinas en los primates, en condiciones normales es un agente antioxidante endógeno y participa en varias vías fisiológicas, sin embargo, cuando los niveles séricos de urato se incrementan, estos participan en el desarrollo de diversas enfermedades. Desde el siglo XIX se conoce de la asociación entre hiperuricemia y daño renal, aunque ninguna guía de manejo recomienda el uso de fármacos hipouricemiantes en pacientes asintomáticos, en algunos casos especiales, el manejo farmacológico beneficiará a pacientes con hiperuricemia, brindando protección al riñón y disminuyendo el riesgo de desarrollar enfermedad renal terminal. Objetivo: describir la relación entre hiperuricemia y daño renal, y analizar los casos en los que el manejo de esta condición con medicamentos resultará en un beneficio para el riñón de los pacientes. Metodología: revisión de la literatura sobre la participación de la hiperuricemia en el daño renal y análisis de los artículos revisados. Resultados: el manejo de la hiperuricemia asintomática puede proteger el riñón en algunas situaciones específicas. Conclusiones: hay situaciones específicas para la disminución de los niveles séricos de ácido úrico.

Background: Uric acid is the end product of purine degradation in primates, under normal conditions it is an endogenous antioxidant agent and participates in several physiological pathways. However, when serum urate levels are increased, they participate in the development of various diseases. Since the nineteenth century, the association between hyperuricemia and kidney damage has been known. Although no management guideline recommends the use of hypouricemic drugs in asymptomatic patients, in some special cases pharmacological management will benefit patients with hyperuricemia, providing protection to the kidney and decreasing the risk of developing end-stage renal disease. Purpose: To describe the relationship between hyperuricemia and kidney damage, and to analyze the cases in which the management of this condition with medications will result in a benefit for the kidney of patients. Methodology: Review of the literature on the involvement of hyperuricemia in kidney damage, analysis of the reviewed articles. Results: Management of asymptomatic hyperuricemia may protect the kidney in some specific situations. Conclusions: There are specific situations for the decrease of serum uric acid levels.

A putative siderophore receptor of Gallibacterium anatis 12656-12 under Fur control also binds hemoglobin.

Pasteurellaceae family members obtain iron directly from host proteins or through siderophore-dependent mechanisms. Although Gallibacterum anatis expresses different virulence factors, its response to growth under iron restriction is unknown. G. anatis cultured in the presence of 2,2'-dipyridyl, up-expressed an approximately 65 kDa protein and repressed the expression of a 70 kDa protein. MALDI-TOF analysis of those proteins indicated homology with CirA (65 kDa), a protein involved in iron-siderophore acquisition in Mannheimia succinoproducens and a TonB-dependent receptor (70 kDa protein), a protein that binds chicken hemoglobin; however, G. anatis siderophore production was not detected by chromo azurol S (CAS)-BHI agar determination. This putative G. anatis siderophore receptor is under Fur control, but not the hemoglobin binding protein, as observed in G. anatis 12656-12 fur mutant (Ω fur 126.13) grown in the presence or not of 2,2'-dipyridyl. The addition of FeCl3 to the culture medium diminished the growth and biofilm production in approximately 30% and 35%, respectively, in the wild-type strain, but the growth of Ω fur 126.13 strain was not affected and biofilm production increased in 35%. G. anatis Ω fur 126.13 presented lower virulence when it was inoculated to 35-day-old chickens in comparison to the wild-type strain. The induction of more than one iron uptake mechanism could benefit pathogenic microorganisms such as Gallibacterium.

2640 Meters Closer to the Stars: Does High Altitude Affect Fontan Results?

BACKGROUND: Risk factors for and postoperative results of the Fontan operation in patients living at high altitude (>2500 meters above sea level) in the Andean region remain unknown. This study was conducted to evaluate immediate postoperative outcomes and to assess short- and long-term functional class after the Fontan operation. METHODS: From June 2003 to February 2019, 104 patients receiving the Fontan procedure at 2640 meters (8661 feet) above sea level were retrospectively studied. Preoperative catheterization, intraoperative variables, and postoperative outcomes were described. Functional class was evaluated in patients living permanently below (group I) and at or higher than 2500 meters (8202 feet) above sea level (group II). Risk factors for mortality were analyzed. RESULTS: Median age at operation was 8.5 ± 4.4 years; pulmonary artery pressure, 16.2 ± 3.6 mm Hg; end-diastolic systemic ventricular pressure, 13.3 ± 3.8 mm Hg; and pulmonary vascular resistance index, 2.1 (interquartile range, 07-3.7) Wood units. Chest tube duration was 8.5 (6-12) days. Mortality was 4.8%, with 0 in the last 5 years. Higher preoperative pulmonary pressure (16.2 ± 3.6 mm Hg vs 21.2 ± 3.40 mm Hg; P = .01), aortic cross-clamp time (P < .001), and renal failure (P < .01) were associated with mortality. Functional class improved to class I in 86.4%. Overall survival was 90.7% at 10 years of follow-up. CONCLUSIONS: Increased pulmonary pressure and pulmonary vascular resistance index are directly related to high altitude. The Fontan-Kreutzer operation performed at high altitude in the Andean region is feasible with good results. We routinely fenestrate all cases to avoid dysfunction in the early postoperative period. Functional status is adequate after the operation.

Correlation between epicardial fat thickness with intima-media thickness and ankle-brachial index in patients with metabolic syndrome.

Background An increase in epicardial fat thickness (EFT) has been associated with increased cardiovascular risk and the development of atherosclerosis. Transthoracic echo-cardiography provides a reliable measurement of EFT. We evaluated the relationship of EFT with carotid intima-media thickness (CIMT) and ankle-brachial index (ABI), in patients with metabolic syndrome. Methods We assessed 80 patients with metabolic syndrome who underwent echocardiography; EFT was measured by two cardiologists. The CIMT (B-mode colour imaging of extracranial carotid arteries using high-resolution ultrasound) was also measured by a certified ultrasonographer, and ABI was measured by the main researcher. Results We did not find any correlation between ABI with EFT (r=0.0103, p=0.93) or with CIMT (r=-0.1625, p=0.15). However, we found a significant correlation between EFT and CIMT (r=0.2718, r2=0.074, p=0.015). When we evaluated the risk for a CIMT >0.9 mm in patients with an EFT >3 mm, we found a statistically significant association (p=0.039). Interestingly, only 1 patient with an EFT <3 mm had a CIMT >0.9 mm. Conclusion We found that the EFT correlates with CIMT in patients with metabolic syndrome, which explains, at least in part, the higher risk of atherosclerosis in them. Measurement of EFT should be part of the cardiovascular risk evaluation in patients with metabolic syndrome.

Acute responses of muscle oxygen saturation during different cluster training configurations in resistance-trained individuals.

This study compared the perceptual responses, physiological indicators and technical parameters between different training protocols focused on upper body exercises. A randomized crossover design was performed, and 12 trained individuals (age: 27.1 ± 5.7 years; height: 173.7 ± 10.7 cm; BMI: 23.9 ± 2.3) completed three resistance training sessions under different protocols separated by at least 72 h: traditional training (TT) (4 x 6 repetitions at 85% of 1RM with 120 s of rest between sets), cluster 1 (CL1) (4 x 2+2+2 repetitions at 85% of 1RM with 15 s of intra-rep rest and 80 s between sets), and cluster 2 (CL2) (24 repetitions at 85% of 1RM with 15 s of inter-set recovery). Before training, arterial blood pressure (BP) and repetitions to failure of pull-up and push-up (FT) were collected. Muscle oxygen saturation (SmO2) in the chest and movement velocity were evaluated in barbell bench press during the training session. After finishing, lactate, BP, rate of perceived exertion and FT were assessed. The percentage of velocity loss (TT: 19.24%; CL1: 5.02% and CL2: 7.30%) in the bench press and lactate concentration (TT: 8.90 mmol·l-1; CL1: 6.13 mmol·l-1 and CL2: 5.48 mmol·l-1) were significantly higher (p < 0.05) for TT compared to both CLs. RPE values were higher (p < 0.05) in TT compared to CL1 (7.95 a.u. vs. 6.91 a.u., respectively). No differences (p > 0.05) were found between protocols for SmO2, BP, FT, pain or heart rate between set configurations. Cluster configurations allow one to maintain higher movement velocity and lower lactate and RPE values compared to a traditional configuration, but with similar concentrations of SmO2.

Epidemiology of thymic epithelial tumors: 22-years experience from a single-institution.

BACKGROUND: To assess the correlation of WHO histological classification and Masaoka-Koga staging system of thymic epithelial tumors (TETs) with prognosis. METHODS: We retrospectively analyzed 83 patients with TETs in the Instituto Nacional de Enfermedades Neoplasicas between 1996 to 2018. We analyzed the clinical stages, histological types and treatment modalities and attempted to determine the impact on overall survival. The data was retrieved from clinical files and reviewed by a pathologist who reclassificated according to the 2004 WHO classification system. The staging was performed with the Masaoka-Koga staging system. Survival curves were constructed with Kaplan-Meir method. RESULTS: There was a total of 83 patients with a median age of 55 years old included in the study. The histological type corresponded to thymoma (T) in 63.8% (n = 53) and to thymic carcinoma (TC) in 36.1%. T were type A, AB, B1, B2 and B3 in 14.4%, 18%, 12%, 3.6%, 7.4% of cases, respectively. The proportion of advanced disease (Masaoka stage III-IV) was high (65%). With a median follow-up of 88.4 months, median overall survival (OS) was 81.6 months for T and 12.3 months for TC (P = 0.01). Univariate analysis showed that sex, histological type, clinical stage and surgery (P = 0.01) were significant independent prognostic factors. On multivariate analysis, histology type and Masaoka-Koga staging had an effect on survival. CONCLUSIONS: The results indicates a clear association between the WHO histological classification and Masaoka-Koga staging system with survival. We found a higher proportion of TETs with advanced disease at diagnosis. Further research are required and collaboration is important to foster knowledge focused on classification and treatment. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY: The WHO histological classification, the Masaoka-Koga system and surgery treatment were associated with overall survival. WHAT THIS STUDY ADDS: To determine prognosis factors in TETs.

Morbilidad por infecciones de partes blandas superficiales en el servicio de clínicas pediátricas de Manzanillo, Granma 2018 / Morbidity caused by soft tissue infections in the services of pediatric clinic in Manzanillo, Granma, 2018

RESUMEN Introducción: Las infecciones de la piel y partes blandas son frecuentes en los niños, con un amplio espectro de gravedad. Objetivo: Describir las características clínico-epidemiológicas de los pacientes con infecciones de partes blandas superficiales hospitalizados en el servicio de clínicas pediátricas del Hospital Pediátrico Docente "Hermanos Cordové". Método: Se realizó un estudio observacional, descriptivo y transversal en el servicio de clínicas pediátricas del Hospital Pediátrico Docente "Hermanos Cordové", de Manzanillo durante el 2018.Se estudiaron todos los pacientes egresados (n=298) con el diagnóstico confirmado de este tipo de infecciones. Se tomaron en cuenta las siguientes variables: localización anatómica, clasificación del tipo deinfección de piel y tejidos blandos, terapéutica utilizada y estadía hospitalaria. Resultados: Predominó el sexo masculino (57,7 %) y el grupo de edad de 10-14 años (34,9 %). Las infecciones en las extremidades estuvieron presentes en 113 pacientes (37,9 %). El impétigo fue la entidad clínica más frecuente (42,3 %), la cefazolina fue el antibiótico más utilizado (77,2 %). Se observó que la mayoría de los pacientes (293) solo permaneció hasta 7 días ingresados, con una evolución satisfactoria. Conclusiones: En el servicio de clínicas pediátricas del Hospital Pediátrico Docente "Hermanos Cordové", los pacientes con IPTB se caracterizan por ser sobre todo varones, más comúnmente con edad entre 10 y 14 años, las lesiones predominaron en las extremidades y la más común fue el impétigo. La cefazolina resultó eficaz para el tratamiento estas infecciones, lo que hizo posible que la estadía hospitalaria generalmente no excediera de siete días.

ABSTRACT Introduction: Infections in the skin and soft tissues are common health concerns in children, with a wide range of severity from patient to patient. Objective: To describe the clinical-epidemiological characteristics of the patients with soft tissue infections hospitalized in the Pediatric Teaching Hospital "Hermanos Cordové". Method: An observational, descriptive, cross-sectional study was carried out in the services of pediatric clinic in the Pediatric Teaching Hospital "Hermanos Cordové", in Manzanillo, Cuba, during the year 2018. All discharged patients who had a confirmed diagnosis of this type of infection were studied (n=298). The following variables were taken into account: anatomical location, classifications of the different types of skin and soft tissue infections, treatment used and hospitalization. Results: Male gender prevailed in the patients (57.7 %), and also the ages ranging between 10 to 14 years old (34.9 %). Infections located on the limbs were described in 113 patients (37.9 %). Impetigo was the most common diagnosis (42.3 %), and the most frequently used antibiotic was cefazolin (77.2 %). Most of the patients were hospitalized up to 7 days (293), with a satisfactory evolution of the disease. Conclusions: Patients with soft tissue infections in the services of pediatric clinic in the Pediatric Teaching Hospital "Hermanos Cordové" are mainly characterized for being male, especially from ages raging between 10 to 14 years old, with impetigo being the most common infection, mostly located on the limbs. Cefalozin resulted very effective for the treatment of these infections, making possible the hospitalization time to be lesser than a week.

El índice neutrófilo/linfocito como predictor de morbilidad y mortalidad en neumonía por influenza / The neutrophil/lymphocyte index as a predictor of morbidity and mortality in pneumonia due to influenza

Resumen: OBJETIVO: Demostrar si el índice neutrófilo/linfocito predice la mortalidad en pacientes con neumonía tipo influenza. MATERIAL Y MÉTODO: Estudio de casos y controles, observacional, analítico, transversal, retrospectivo y retrolectivo que incluyó pacientes con neumonía por influenza que padecieron neumonía aguda grave de 2009 a 2017. Se calculó APACHE II, SMART COP y el índice neutrófilo/linfocito (INL). Se determinó supervivencia mediante Kaplan y Meier, para la asociación entre INL y mortalidad, APACHE II, SMART COP y comorbilidades se usó χ2 y razón de momios (RM), así como correlación entre APACHE II, SMART COP e INL. RESULTADOS: Se incluyeron 69 pacientes. La RM entre el INL y la mortalidad fue de 0.174 (p = 0.533; IC95% 0.274 a 2.08). Hubo asociación significativa entre el INL y componentes del síndrome metabólico en pacientes vivos. No hubo diferencia en la supervivencia entre INL mayor o menor de 7. Correlación positiva entre APACHE II e INL de 0.4295 (p = 0.0002; IC95% 0.00 a 0.063). CONCLUSIONES: Existe asociación entre el INL y el síndrome metabólico en pacientes vivos, así como correlación positiva con APACHE II. No hay asociación entre el INL y mortalidad. El punto de corte del INL se desplazó cuatro puntos comparado con otras poblaciones.

Abstract: OBJECTIVE: To demonstrate if neutrophil/lymphocyte index predicts mortality in patients with influenza-like pneumonia. MATERIAL AND METHOD: A case-control, observational, analytical, cross-sectional, retrospective and retrolective study with patients with influenza like pneumonia who developed severe acute pneumonia from 2009 to 2017. APACHE II, SMART COP and neutrophil lymphocyte index (INL) were calculated. Survival was determined by Kaplan and Meier, for the association between INL and mortality, APACHE II, SMART COP and comorbidities was used χ2 and odds ratio (OR), as well as correlation between APACHE II, SMART COP and INL. RESULTS: There were included 69 patients. OR between the INL and mortality was of 0.174 (p = 0.533, IC95% 0.274-2.08). There was significant association between INL and components of the metabolic syndrome in living patients. There was no difference in survival between INL greater or less than 7. Positive correlation between APACHE II and INL of 0.4295 (p = 0.0002, IC95% 0.00 to 0.063). CONCLUSIONS: There is an association between INL and metabolic syndrome in liv- ing patients, as well as a positive correlation with APACHE II. There is no association between INL and mortality. The cutoff point of the INL shifted 4 points compared to other populations.

Triglycerides and waist to height ratio are more accurate than visceral adiposity and body adiposity index to predict impaired fasting glucose.

AIMS: To evaluate the clinical accuracy of novel indices visceral adiposity index (VAI) and body adiposity index (BAI) to identify patients with impaired fasting glucose (IFG) and compare with its individual components and other obesity indicators. METHODS: A cross-sectional study was conducted in Mexican population. Body mass index (BMI), waist circumference, hip circumference, triglycerides (TG), High density lipoprotein cholesterol (HDL-C), VAI, BAI, waist to hip ratio (WHR) and waist to height ratio (WHtR) were determined. We plotted a receiver operating characteristic curves to assess the abilities to discriminate subjects with IFG from those with normal glucose tolerance (NGT) of the measurements. A binary logistic regression analysis was performed to determine the strength of association with IFG. RESULTS: A total of 280 individuals were included, from which 144 (51.3%) have IFG; the mean age was 47.14 years and 164 (55.5%) were females. Compared with NGT subjects, the participants with IFG had significantly higher levels of BMI, WHtR, VAI, BAI and TG. The measurements with highest area under the curve were TG, (0.631, 95% confidence interval [CI] 0.566-0.697) VAI (0.628, 95% CI 0.563-0.693) and WHtR (0.622, 95% CI 0.557-0.688) and in the adjusted binary logistic regression model, were found to be independently associated with IFG, Odds Ratio of 2.665, (95% CI 1.567-4.533) 2.567 (95% CI 1.527-4.317) and 2.171 (95% CI 1.102-4.276) respectively. CONCLUSIONS: Our data provide evidence that TG, VAI and WHtR could be considered potential tools for the risk assessment of type 2 diabetes mellitus (T2DM) in this population.

A Monte Carlo detector response model for the IRIS PET preclinical scanner.

PET preclinical studies require high spatial resolution due to the limited size of the animal under investigation. To achieve this target, iterative image reconstruction algorithms are commonly preferred over the analytical methods because they offer the possibility of accurately modeling the whole imaging process. In this work, we propose an accurate factorized system matrix for the INVISCAN IRIS preclinical PET scanner to be used with an iterative algorithm. The model includes two components: the geometric component and the detector response of the system. The main innovative aspect of the work is the creation of the detector matrix using a Monte Carlo simulation, with a particular focus on the optimization of the simulation process to reduce the calculation time. The new system model is compared with the current IRIS model to evaluate the image quality, following the NEMA Standards NU 4-2008. The comparison showed an enhancement of the image quality, in terms of uniformity and recovery coefficients. This work confirms that the inclusion of the detector response into the system model leads to improved reconstruction results.

An automatic algorithm to exploit the symmetries of the system response matrix in positron emission tomography iterative reconstruction.

Positron emission tomography (PET) iterative 3D reconstruction is a very computational demanding task. One of the main issues of the iterative reconstruction concerns the management of the system response matrix (SRM). The SRM models the relationship between the projection and the voxel space and its memory footprint can easily exceed hundreds of GB. Moreover, in order to make the reconstruction fast enough not to hinder its practical application, the SRM must be stored in the random access memory of the workstation used for the reconstruction. This issue is normally solved by implementing efficient storage schemes and by reducing the number of redundant patterns in the SRM through symmetries. However, finding a sufficient number of symmetries is often non-trivial and is typically performed using dedicated solutions that cannot be exported to different detectors and geometries. In this paper, an automatic approach to reduce the memory footprint of a pre-computed SRM is described. The proposed approach was named symmetry search algorithm (SSA) and consists in an algorithm that searches for some of the redundant patterns present in the SRM, leading to its lossy compression. This approach was built to detect translations, reflections and coordinates swap in voxel space. Therefore, it is particularly well suited for those scanners where some of the rotational symmetries are broken, e.g. small animal scanner where the modules are arranged in a polygonal ring made of few elements, and dual head planar PET systems. In order to validate this approach, the SSA is applied to the SRM of a preclinical scanner (the IRIS PET/CT). The data acquired by the scanner were reconstructed with a dedicated maximum likelihood estimation maximization algorithm with both the uncompressed and the compressed SRMs. The results achieved show that the information lost due to the SSA compression is negligible. Compression factors up to 52 when using the SSA together with manually inserted symmetries and up to 204 when using the SSA alone, can be obtained for the IRIS SRM. These results come without significant differences in the values and in the main quality metrics of the reconstructed images, i.e. spatial resolution and noise. Although the compression factors depend on the system considered, the SSA is applicable to any SRM and therefore it can be considered a general tool to reduce the footprint of a pre-computed SRM.

Prehypertension is associated with peripheral arterial disease and low ankle-brachial index.

Patients with prehypertension suffer endothelial dysfunction and are at increased cardiovascular risk. Ankle-brachial index (ABI) constitutes an efficient tool for diagnosing peripheral arterial disease; but also an ABI<0.9 is an independent and positive predictor of endothelial dysfunction and is associated with increased cardiovascular risk and mortality. THE AIM: of this study was testing whether ABI was decreased in prehypertensive patients when compared with normotensive subjects. METHODS: We included 70 prehypertensive patients older than 19 years, in whom the ABI was registered with a 5 megahertz Doppler (Summit Doppler L250, Life Dop., USA). The highest ankle systolic pressure was divided by the highest brachial systolic pressure. We also included 70 normotensive subjects in whom the ABI was registered in the same way. The measurements were performed by the same physician who was blinded about the study. Statistical analysis was performed with odds ratio and student t-test. RESULTS: The ABI values in normotensive subjects were 1.023±0.21, whereas prehypertensive patients significantly had lower ABI (0.90±0.14p=0.00012). We found ABI <0.9 in 30 prehypertensive patients (42.85%) and 13 normotensive patients (18.5%). The odds ratio of ABI <0.90 in prehypertensive patients was 3.288 (IC95 1.5-7.0, p=0.0023). A regression analysis failed to show any independent association between ABI values and any other clinical parameter. CONCLUSIONS: Prehypertensive patients had lower ABI and higher prevalence of peripheral artery disease when compared with normotensive subjects; this fact increases their cardiovascular risk. ABI must be included in global evaluation of prehypertensive subjects.

Correlación entre el grosor de la grasa epicárdica y los marcadores bioquímicos de riesgo metabólico / Correlation between epicardial fat thickness and biochemical markers of metabolic risk

Introducción y objetivo: La grasa epicárdica se asocia a riesgo cardiovascular y aterosclerosis, y puede ser medida en forma fiable por ecocardiografía. Nuestro objetivo es evaluar si existe asociación entre el grosor de la grasa epicárdica (GGE) con marcadores bioquímicos de riesgo metabólico. Material y método: Evaluamos 211 pacientes en quienes se realizó la medición del GGE por ecocardiografía. También se les se realizó glucemia, perfil de lípidos y niveles séricos de ácido úrico. Los métodos estadísticos usados fueros odds ratio y coeficiente de correlación y determinación de Pearson. Resultados: No encontramos correlación entre GGE con glucemia (r=0,064), colesterol total (r=0,005), colesterol ligado a lipoproteínas de alta densidad (r=-0,038), ni triglicéridos (r=0,118). Sin embargo, encontramos una correlación significativa entre el GGE con la uricemia (r=0,415, p<0,00001). La odds ratio para presentar GGE>3mm en pacientes con hiperuricemia fue de 6,26 (IC 95%: 2,79-14, p<0,0001). Conclusión: La hiperuricemia se correlaciona significativamente con el GGE en nuestra población. La medición del GGE por ecocardiografía puede ser un método de utilidad para evaluar el riesgo cardiovascular

Introduction and objective: Epicardial fat has been associated with increased cardiovascular risk and the development of atherosclerosis. Transthoracic echocardiography provides a reliable measurement of epicardial fat thickness (EFT). The aim of this study is to evaluate the relationship between EFT and biochemical parameters of metabolic risk. Material and method: We assessed 211 patients who underwent echocardiography; EFT was measured by two cardiologists. In addition, patients’ glycaemia, lipid profile and serum uric acid were measured. Statistical analysis was performed with the Pearson coefficient test and Odds ratio. Results: A positive correlation between EFT with glycaemia (r=.064), total serum cholesterol (r=.0056), high density lipoproteins (r=-0.038), or with triglycerides (r=.118) was not observed. However, we did find a significant positive correlation between EFT and serum uric acid (r=.415, P<.00001). The odds ratio for EFT>3mm in patients with hyperuricemia was 6.26 (IC 95 2.79-14, P<.0001). Conclusion: Hyperuricemia is strongly associated with EFT in Mexican patients; EFT is a useful tool for global cardiovascular risk calculation