[Radiation exposure of the spine surgeon]. / Exposición a radiación del cirujano de columna.

INTRODUCTION: in general, spine surgeons seek to minimize soft tissue damage by using less invasive approaches, which causes them to use intraoperative images much more frequently than other surgical specialties; therefore, they are at increased risk of radiation exposure. OBJECTIVE: the aim of this work was to analyse the amount of radiation to which the spine surgeon is exposed in different scenarios. MATERIAL AND METHODS: a prospective study with a descriptive, longitudinal non-randomized data source. We carried out this study in the period from 2015 to 2019, the radiologic protection consisted in lead apron, thyroid shield and leaded glasses, there were 10 badge dosimeters. RESULTS: only 4 dosimeters were included in the study, the other six were excluded. During the study period one surgeon suffered thyroid cancer and other suffered of liposarcoma. In the protected group were two surgeons, in the group of aleatory exposition was one surgeon and in the unprotected group was one surgeon. In the study the dosimeter in the unprotected group received more amount of radiation in all the years, we did an inferential analysis per year related with the number of surgeries without significant correlation, we attribute this result because we didn't classified the type of surgery realized by each surgeon. CONCLUSION: we conclude that the spine surgeon must apply the primary methods of radiological protection and that the unprotected spine surgeon receives more amount of radiation in comparison of the protected ones.

INTRODUCCIÓN: en general, los cirujanos de columna buscan minimizar el daño a tejidos blandos empleando abordajes menos invasivos, lo que ocasiona que utilicen imágenes intraoperatorias de una manera mucho más habitual que el resto de las especialidades quirúrgicas; por lo tanto, están en mayor riesgo de exposición de radiación. OBJETIVO: el propósito del trabajo es analizar la cantidad de radiación a la cual está expuesto el cirujano de columna en diferentes escenarios. MATERIAL Y MÉTODOS: estudio prospectivo con una fuente de datos descriptiva, longitudinal, no aleatorizada. Se llevó a cabo el estudio en el período del año 2015 al 2019; la protección radiológica consistió en chaleco plomado, protector de tiroides y lentes plomados; se usaron 10 dosímetros. RESULTADOS: cuatro dosímetros fueron incluidos en el estudio, los otros seis fueron excluidos. Durante el estudio, un cirujano sufrió de cáncer de tiroides y otro de liposarcoma. En el grupo de protegidos se incluyeron dos cirujanos, en el grupo de protección aleatorizada se incluyó un cirujano y en el grupo sin protección se incluyó un cirujano. El dosímetro del grupo sin protección recibió mayor cantidad de radiación en todos los años, se realizó un análisis inferencial por año relacionado con el número de cirugías no encontrando correlación significativa, atribuimos este resultado a que no clasificamos el tipo de cirugía realizada por cada cirujano. CONCLUSIÓN: el cirujano de columna debe de aplicar los métodos primarios de protección radiológica, ya que los cirujanos de columna sin equipo de protección reciben mayor cantidad de radiación en comparación con los protegidos.

Exposición a radiación del cirujano de columna / Radiation exposure of the spine surgeon

Resumen: Introducción: en general, los cirujanos de columna buscan minimizar el daño a tejidos blandos empleando abordajes menos invasivos, lo que ocasiona que utilicen imágenes intraoperatorias de una manera mucho más habitual que el resto de las especialidades quirúrgicas; por lo tanto, están en mayor riesgo de exposición de radiación. Objetivo: el propósito del trabajo es analizar la cantidad de radiación a la cual está expuesto el cirujano de columna en diferentes escenarios. Material y métodos: estudio prospectivo con una fuente de datos descriptiva, longitudinal, no aleatorizada. Se llevó a cabo el estudio en el período del año 2015 al 2019; la protección radiológica consistió en chaleco plomado, protector de tiroides y lentes plomados; se usaron 10 dosímetros. Resultados: cuatro dosímetros fueron incluidos en el estudio, los otros seis fueron excluidos. Durante el estudio, un cirujano sufrió de cáncer de tiroides y otro de liposarcoma. En el grupo de protegidos se incluyeron dos cirujanos, en el grupo de protección aleatorizada se incluyó un cirujano y en el grupo sin protección se incluyó un cirujano. El dosímetro del grupo sin protección recibió mayor cantidad de radiación en todos los años, se realizó un análisis inferencial por año relacionado con el número de cirugías no encontrando correlación significativa, atribuimos este resultado a que no clasificamos el tipo de cirugía realizada por cada cirujano. Conclusión: el cirujano de columna debe de aplicar los métodos primarios de protección radiológica, ya que los cirujanos de columna sin equipo de protección reciben mayor cantidad de radiación en comparación con los protegidos.

Abstract: Introduction: in general, spine surgeons seek to minimize soft tissue damage by using less invasive approaches, which causes them to use intraoperative images much more frequently than other surgical specialties; therefore, they are at increased risk of radiation exposure. Objective: the aim of this work was to analyse the amount of radiation to which the spine surgeon is exposed in different scenarios. Material and methods: a prospective study with a descriptive, longitudinal non-randomized data source. We carried out this study in the period from 2015 to 2019, the radiologic protection consisted in lead apron, thyroid shield and leaded glasses, there were 10 badge dosimeters. Results: only 4 dosimeters were included in the study, the other six were excluded. During the study period one surgeon suffered thyroid cancer and other suffered of liposarcoma. In the protected group were two surgeons, in the group of aleatory exposition was one surgeon and in the unprotected group was one surgeon. In the study the dosimeter in the unprotected group received more amount of radiation in all the years, we did an inferential analysis per year related with the number of surgeries without significant correlation, we attribute this result because we didn't classified the type of surgery realized by each surgeon. Conclusion: we conclude that the spine surgeon must apply the primary methods of radiological protection and that the unprotected spine surgeon receives more amount of radiation in comparison of the protected ones.

Training a quantum measurement device to discriminate unknown non-orthogonal quantum states.

Here, we study the problem of decoding information transmitted through unknown quantum states. We assume that Alice encodes an alphabet into a set of orthogonal quantum states, which are then transmitted to Bob. However, the quantum channel that mediates the transmission maps the orthogonal states into non-orthogonal states, possibly mixed. If an accurate model of the channel is unavailable, then the states received by Bob are unknown. In order to decode the transmitted information we propose to train a measurement device to achieve the smallest possible error in the discrimination process. This is achieved by supplementing the quantum channel with a classical one, which allows the transmission of information required for the training, and resorting to a noise-tolerant optimization algorithm. We demonstrate the training method in the case of minimum-error discrimination strategy and show that it achieves error probabilities very close to the optimal one. In particular, in the case of two unknown pure states, our proposal approaches the Helstrom bound. A similar result holds for a larger number of states in higher dimensions. We also show that a reduction of the search space, which is used in the training process, leads to a considerable reduction in the required resources. Finally, we apply our proposal to the case of the phase flip channel reaching an accurate value of the optimal error probability.

Diagnóstico de parasitosis gastrointestinal en ganado vacuno de razas carniceras con diferentes técnicas coproparasitológicas / Diagnosis of gastrointestinal parasitosis in beef cattle of butcher breeds with different coproparasitological techniques

RESUMEN Las parasitosis gastrointestinales en bovinos de producción son uno de los problemas sanitarios más importantes a nivel mundial. Estos nematodos ocasionan problemas gastroentéricos que se caracterizan clínicamente por diarrea, debilidad, hemorragias y deshidratación. Entre las parasitosis gastrointestinales causadas por nematodos en ganado bovino, se destacan las familias: Trichuridae, Trichostrongylidae, Ancylostomidae, Ascaridae y Strongyloididae. El propósito de esta investigación fue determinar la eficacia de las distintas técnicas coproparasitológicas cualitativas y cuantitativas para la detección de nematodos gastrointestinales en ganado bovino. Para este estudio se utilizaron 250 muestras de vacas de raza carnicera, divididos en diferentes grupos, para la aplicación de las técnicas coproparasitológicas de tipo cualitativo y cuantitativo, los cuales fueron escogidos específicamente teniendo en cuenta criterios de inclusión y exclusión para cada animal. Los resultados entregados por este estudio indicaron que el mayor porcentaje en la identificación de estados infectantes parasitarios fue por medio de las técnicas coproparasitologicas de tipo cualitativo, principalmente aquellas de flotación de sulfato de zinc y magnesio con un 50%.

ABSTRACT Gastrointestinal parasites in production cattle are one of the most important health problems worldwide. These nematodes cause gastroenteric problems that are clinically characterized by diarrhoea, weakness, bleeding and dehydration. Within the gastrointestinal parasites caused by nematodes in cattle, the following families stand out: Trichuridae, Trichostrongylidae, Ancylostomidae, Ascaridae and Strongyloididae. The purpose of this research was to determine the efficacy of the different qualitative and quantitative coproparasitological techniques for the detection of gastrointestinal nematodes in cattle. For this study, 250 samples of beef breed cows were used, divided into different groups, for the application of qualitative and quantitative coproparasitological techniques, which were specifically chosen taking into account inclusion and exclusion criteria for each animal. The results delivered by this study indicated that the highest percentage in the identification of parasitic infective states was through qualitative coproparasitological techniques, focused mainly on zinc and magnesium sulfate flotation techniques with 50%.

Bioactive ingredients of huitlacoche (Ustilago maydis), a potential food raw material.

Huitlacoche (Ustilago maydis) is a staple food traditionally consumed in Mexico. On one hand, it is considered a pathogen and a devastating disease for maize (Zea mays), and, conversely, some reports highlight it as a culinary delight and a food alternative for its nutritional and functional characteristics. The present work aimed to compare two different methods: maceration and ultrasound-assisted extraction (UAE), in order to achieve the highest amount of total phenolic compounds (TPC), followed by the antioxidant capacity (AC) measurement, as well as the effect of the in vitro digestion. UAE produced the highest TPC content (13.44 mg GAE/mg ds) for a 1:5 huitlacoche:solvent ratio using ethanol at 75%. The maximum values for AC were 22.5 mg TE/mL (for DPPH assay) and 45.26 mg TE/mL (for ABTS assay). The in vitro digestion showed that AC is maintained and increased through the digestion process. Thus, huitlacoche can be revalorised as a potential food raw material for human nutrition and health.

Utilidad de la tomografía computada de cavidades paranasales como evaluación otorrinolaringológica pretrasplante renal / Usefulness of computed tomography of the paranasal sinus as a kidney pre-transplant otorhinolaryngological evaluation

Resumen Introducción: El trasplante renal corresponde al tratamiento de elección para la enfermedad renal crónica. No existe un protocolo universalmente aceptado para la evaluación otorrinolaringológica del receptor del riñón a implantar, existiendo una gran heterogeneidad en su práctica. La tomografía computada de cavidades paranasales es uno de los estudios más habitualmente utilizados para descartar patologías otorrinolaringológicas que contraindiquen la intervención. Objetivo: Describir los hallazgos imagenológicos de las tomografías computadas solicitadas como evaluación pretrasplante renal. Determinar si estos hallazgos condicionaron una contraindicación para trasplante o algún cambio en el manejo del paciente. Material y Método: Estudio descriptivo de corte transversal mediante la revisión de fichas clínicas de pacientes derivados a estudio pretrasplante renal durante el año 2018 en el Hospital Carlos Van Buren. Resultados: Se obtuvo información de 40 pacientes derivados para evaluación otorrinolaringológica. El promedio de edad fue de 49 ± 11,4 años; 55% fueron mujeres. La causa más frecuente de enfermedad renal fue idiopática (70%). A 34 de 40 pacientes se les solicitó evaluación tomográfica. A cinco pacientes se les indicó corticoides intranasales y se derivó un paciente a evaluación dental. No se generó ninguna contraindicación para el trasplante renal. Discusión: Existe poca literatura sobre la utilidad de la tomografía de cavidades paranasales como estudio pretrasplante renal. En el presente estudio no se encontró ningún hallazgo que contraindicara la intervención. Conclusión: Se necesitan más estudios para poder asegurar si la evaluación otorrinolaringológica y el uso de tomografía tiene alguna implicancia en la evolución de los pacientes sometidos a trasplante renal.

Abstract Introduction: Kidney transplantation is the treatment of choice for chronic kidney disease. There is no universally accepted protocol for the otorhinolaryngological evaluation of the recipient, and there is heterogeneity in clinical practice. Computed tomography of the paranasal cavities is one of the most commonly used studies to rule out otorhinolaryngological pathologies that contraindicate the intervention. Aim: To describe the imaging findings of the computed tomographies requested as a pre-transplant evaluation. To determine if these findings determined a contraindication for transplantation or any change in the patient's management. Material and Method: Descriptive cross-sectional study by reviewing the clinical records of patients referred to a pre-kidney transplant study during 2018 at the Hospital Carlos Van Buren. Results: Information was obtained from 40 patients referred for otorhinolaryngological evaluation. The average age was 49 ± 11.4 years; 55% were women. The most common cause of kidney disease was idiopathic (70%). 34 of 40 patients had a computed tomography. Five patients received intranasal corticosteroids and one patient was referred for dental evaluation. There were no contraindications for renal transplantation. Conclusion: There is little literature on the usefulness of paranasal cavity tomography as a pre-kidney transplant study. In the present study, no finding was found that would contraindicate the intervention. More studies are needed to be able to ascertain whether the otorhinolaryngological evaluation and the use of tomography have any implications in the evolution of patients undergoing kidney transplantation.

Effect of melatonin administration on the PER1 and BMAL1 clock genes in patients with Parkinson's disease.

Sleep disorders are a widespread condition in patients with Parkinson's disease (PD), which has been linked to a deregulation of the circadian cycle and therefore of the clock genes. The aim of this study was to evaluate the effect of melatonin (MEL) on the PER1 and BMAL1 clock genes in patients with PD. A double-blind, cross-over, placebo-controlled randomized clinical trial pilot study was conducted in 26 patients with stage 1-3 PD according to the Hoehn & Yahr scale, who received either 25 mg of MEL or a placebo at noon and 30 min before bedtime for three months. The relative expression of the PER1 and BMAL1 genes was measured, as well as the presence of daytime, nocturnal, and global sleepiness, and the progression of PD. The levels of the PER1 and BMAL1 genes at baseline were 0.9 (0.1-3) vs. 0.56 (0.1-2.5), respectively; while after the intervention with MEL or placebo the BMAL1 levels increased to 2.5 (0-3.70) vs. 2.2 (0.10-3.30), respectively (d = 0.387). Fifty percent (50 %) of patients had daytime sleepiness and sixty-five percent (65 %) had abnormal nighttime sleepiness, yet neither group showed changes after the intervention. Patients with PD exhibited an alteration in the levels of the clock genes: MEL increased the levels of BMAL1, but the PER1 levels remained unchanged.

Infarto agudo de miocardio sin enfermedad coronaria ateroesclerótica obstructiva: utilidad de las imágenes intravasculares y resonancia cardíaca en su diagnóstico / Myocardial infarction with non-obstructive coronary artery disease. Diagnostic value of intravascular imaging and cardiac resonance

BACKGROUND: Myocardial infarction with non-obstructive coronary artery disease (MINOCA) is common. Cardiac magnetic resonance (CMR) and intravascular imaging (IVI) may be useful for establishing its etiology. AIM: To describe a population with MINOCA and its multi-image assessment using IVI or CMR. MATERIAL AND METHODS: Review of medical records, imaging and functional studies of patients with MINOCA treated in three different clinical centers between 2015 and 2019. RESULTS: Twenty-eight patients with MINOCA and IVI were included. Seventy eight percent were women, 46% had hypertension, 32% smoked and 32% had dyslipidemia. At wall motion assessment, 46% presented apical ballooning pattern. In 36% of patients IVI identified lesions that explained the cause of MINOCA, namely plaque disruption (PD) in 18%, spontaneous coronary dissection in 11% and a thrombus without PD in 7%. Forty-six percent of patients had uncomplicated atherosclerotic plaques, and 36% had no pathological findings. CMR was performed in 50% of patients, identifying in all a diagnostic pattern. In nine cases it was compatible with stress cardiomyopathy, three cases had a myocarditis and two cases had transmural infarctions. PD and transmural late gadolinium enhancement were observed in 23% of patients with apical ballooning. Patients with a pattern of myocarditis did not have acute pathological findings at IVI. After a mean follow-up of 16.4±11.4 months, 3 patients with PD died. CONCLUSIONS: Among patients with MINOCA, there was a predominance of female gender with low cardiovascular risk factor load. The multi-image assessment allowed greater precision for etiological diagnosis of MINOCA. Apical ballooning was not pathognomonic for stress cardiomyopathy. PD was associated with mortality.

[Myocardial infarction with non-obstructive coronary artery disease. Diagnostic value of intravascular imaging and cardiac resonance]. / Infarto agudo de miocardio sin enfermedad coronaria ateroesclerótica obstructiva: utilidad de las imágenes intravasculares y resonancia cardíaca en su diagnóstico.

BACKGROUND: Myocardial infarction with non-obstructive coronary artery disease (MINOCA) is common. Cardiac magnetic resonance (CMR) and intravascular imaging (IVI) may be useful for establishing its etiology. AIM: To describe a population with MINOCA and its multi-image assessment using IVI or CMR. MATERIAL AND METHODS: Review of medical records, imaging and functional studies of patients with MINOCA treated in three different clinical centers between 2015 and 2019. RESULTS: Twenty-eight patients with MINOCA and IVI were included. Seventy eight percent were women, 46% had hypertension, 32% smoked and 32% had dyslipidemia. At wall motion assessment, 46% presented apical ballooning pattern. In 36% of patients IVI identified lesions that explained the cause of MINOCA, namely plaque disruption (PD) in 18%, spontaneous coronary dissection in 11% and a thrombus without PD in 7%. Forty-six percent of patients had uncomplicated atherosclerotic plaques, and 36% had no pathological findings. CMR was performed in 50% of patients, identifying in all a diagnostic pattern. In nine cases it was compatible with stress cardiomyopathy, three cases had a myocarditis and two cases had transmural infarctions. PD and transmural late gadolinium enhancement were observed in 23% of patients with apical ballooning. Patients with a pattern of myocarditis did not have acute pathological findings at IVI. After a mean follow-up of 16.4±11.4 months, 3 patients with PD died. CONCLUSIONS: Among patients with MINOCA, there was a predominance of female gender with low cardiovascular risk factor load. The multi-image assessment allowed greater precision for etiological diagnosis of MINOCA. Apical ballooning was not pathognomonic for stress cardiomyopathy. PD was associated with mortality.

Association between abdominal pain and fecal impaction grade assessed through radiography in constipated patients at a pediatric emergency service. / Asociación entre el dolor abdominal y el grado de coproestasis mediante la evaluación radiográfica en pacientes estreñidos que acuden a los servicios de urgencias pediátricas.

INTRODUCTION AND AIM: Abdominal pain in children is a frequent cause of emergency room consultation. An important group of those patients presents with chronic constipation and fecal impaction. Plain abdominal x-ray is widely used for making a diagnosis and ruling out the need for surgical treatment. The present study examined the association between pain intensity and fecal impaction grade. MATERIALS AND METHODS: An analytic cross-sectional study was conducted that compared 2 radiographic scales to determine the association between the grade of fecal impaction observed and abdominal pain intensity in patients that sought medical attention at an emergency service within a 7-month period. The analysis was carried out by 2 different observers, utilizing 2 different radiographic scales to confirm their reproducibility. The degree of interobserver agreement was measured using the Kappa coefficient and the association between abdominal pain and fecal impaction grade was measured through the Spearman correlation coefficient. RESULTS: There was a significant association between pain intensity and the radiographic grade of fecal impaction (P<.05) for the radiographic scale by segments and its interobserver agreement was high, compared with the scale by percentage. CONCLUSIONS: Radiographic scales may be useful in the evaluation and treatment of patients with abdominal pain and constipation. The segmental scale showed less interobserver variability, suggesting its proposal as an alternative in the evaluation and follow-up of patients with chronic constipation.

Stochastic optimization on complex variables and pure-state quantum tomography.

Real-valued functions of complex arguments violate the Cauchy-Riemann conditions and, consequently, do not have Taylor series expansion. Therefore, optimization methods based on derivatives cannot be directly applied to this class of functions. This is circumvented by mapping the problem to the field of the real numbers by considering real and imaginary parts of the complex arguments as the new independent variables. We introduce a stochastic optimization method that works within the field of the complex numbers. This has two advantages: Equations on complex arguments are simpler and easy to analyze and the use of the complex structure leads to performance improvements. The method produces a sequence of estimates that converges asymptotically in mean to the optimizer. Each estimate is generated by evaluating the target function at two different randomly chosen points. Thereby, the method allows the optimization of functions with unknown parameters. Furthermore, the method exhibits a large performance enhancement. This is demonstrated by comparing its performance with other algorithms in the case of quantum tomography of pure states. The method provides solutions which can be two orders of magnitude closer to the true minima or achieve similar results as other methods but with three orders of magnitude less resources.

Posición del hueso hioides en pacientes con mordida abierta / Hyoid bone position in open bite patients

Objetivo: Evaluar la posición de hueso hioides en pacientes con mordida abierta, mediante el trazado cefalométrico del triángulo hioideo propuesto por Rocabado, Bibby y Preston. Materiales y método: Se analizaron 32 radiografías cefálicas laterales digitales, obtenidas de un centro odontológico de la ciudad de Cuenca, correspondientes a individuos de ambos sexos, entre 5 a 26 años de edad. Las telerradiografías fueron analizadas mediante el programa Nemoceph NX, donde se determinó la posición anteroposterior y vertical del hueso hioides, mediante el trazado cefalométrico del triángulo hioideo propuesto por Rocabado, Bibby y Preston, siendo el mentón, la tercera vértebra cervical y el hueso hioides las estructuras que se utilizaron para realizar dicho trazado. Resultados: Se observó una posición anterosuperior del hueso hioides en individuos con mordida abierta, con un triángulo hioideo positivo, pero no siempre, ya que en algunos de los casos se presentó un triángulo hioideo negativo. Se evidenciaron diferencias estadísticamente negativas entre hombres y mujeres en lo que respecta a la posición vertical del hueso hioides. Esta posición varió en los diferentes grupos etarios, con una posición más superior en un rango de edad menor y descendiendo conforme avanza la edad. Conclusiones: la posición del hueso hioides en pacientes con mordida abierta tiene una tendencia anterosuperior, influenciada por el sexo y la edad. En el presente estudio, casi la mitad de los pacientes presentó un triángulo hioideo positivo (59,4%) pero no en todos los casos, ya que presentaron también un triángulo hioideo negativo (40,6%) (AU)

Enhancing master-slave synchronization: The effect of using a dynamic coupling.

This paper introduces a modified master-slave synchronization scheme for dynamical systems. In contrast to the standard configuration, the slave system does not receive any driving signal from the master, but rather the interaction is through a linear dynamical system. The key feature of the proposed coupling scheme is that it induces synchronization in certain systems that cannot be synchronized when using the classical static interconnection. Likewise, the dynamic coupling achieves synchronization for arbitrarily large coupling strength values in certain systems for which the classical configuration is applicable only within a narrow interval of coupling strength values. The performance of the synchronization scheme is illustrated in pairs of identical chaotic and mechanical oscillators.

Tumor Biology as Predictor of Mortality in Liver Transplantation for Hepatocellular Carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is the most frequent primary malignant liver tumor, with the Milan criteria considered to be the gold standard for patient selection for liver transplantation (LT). MATERIALS AND METHODS: We performed a descriptive observational study, reviewing 20 years of experience of LT in patients with HCC in the Fundacion Valle del Lilí in Cali, Colombia. Subgroup analysis was undertaken for periods 1999 to 2007 and 2008 to 2015. RESULTS: Fifty-seven cases with a pretransplant HCC diagnosis were reviewed. In the first period patients within the Milan criteria had a recurrence-free survival at 5 years of 66.6%, and in those who exceeded the Milan criteria, recurrence-free survival was 75%. In the second period, patients within the Milan criteria, recurrence-free survival at 5 years was 93.5%, and in those who exceeded the Milan criteria, recurrence-free survival was 75.7%. No statistically significant difference was found in either period. For patients with mild and moderate tumor differentiation, the relapse survival rate at 5 years was 69.4% (95% confidence interval [CI] 35.8-87.8) and 74.7% (95% CI 44.5-90), respectively. All patients with poor tumor differentiation relapsed and died within 3 years. CONCLUSION: Global and recurrence-free survival among patients who met and patients who exceeded the Milan criteria was not significantly different, suggesting an expansion of the Milan criteria to include potential recipients who were previously excluded. Obtaining histologic differentiation and identifying vascular invasion will provide a more worthwhile contribution to LT decision making.

Liver Transplantation in Hepatitis C-Infected Patients: Experience From a South American Transplant Center.

BACKGROUND: Around 2.4% of the world's population is infected with hepatitis C virus (HCV), and it is the most common cause of liver transplantation (LT) in the world. Latin America (LA), with nearly 9% of the world population, has had a continuous increase in the number of LTs per year. Yet, due to the lack of mandatory data collection and a well-developed health-care system, access to transplantation is limited in most LA countries. We report the first LA experience of HCV-infected LT patients. METHODS: We performed a retrospective cohort study by reviewing the medical histories of all HCV-infected LT patients between 1996 and 2016 who acquired HCV before their LT, at the Fundación Valle del Lilí, Cali, Colombia. RESULTS: Between January 1996 and December 2015, a total of 770 LTs were performed, of which 75 had a cirrhotic liver due to HCV infection. With a median follow-up time of 24.4 months (interquartile range [IQR] 4.7-61.2 months), patient survival was 44.9% and 66.9% for the time periods 1996-2006 and 2007-2015, respectively. Hepatocellular carcinoma (HCC) was present in 30.6% of the patients, and overall postoperative complications had an incidence of 80%. CONCLUSIONS: This is the first report of LT in HCV-infected patients in Colombia and in LA. Our results are comparable to those of other transplant centers worldwide with regard to postoperative complications and patient survival. Patients with LT in the 1996-2006 time frame had higher morbidity and mortality. Studies including larger numbers of patients are needed to determine the reason for this finding.

Influence of Surface Sealants on Microleakage in Composite Restorations / Estudio de la Influencia de los Sellantes de Superficie sobre la Microfiltración en Restauraciones de Composite

ABSTRACT: Polymerization shrinkage of composites can generate stress that results in the formation of microgaps at the resin-enamel interface and marginal leakage. The aim of the present work was to evaluate the influence of surface sealants on microleakage in composite restorations. Enamel-dentin occlusal cavities were prepared in 30 non-carious upper and lower premolars. The cavities were restored with One Coat Bond SL and Brilliant New Generation (Coletene), following the manufacturers' instructions, and polished appropriately. The samples were randomly assigned to one of the following six treatment groups: Group I (Control-no sealant); Group II: Single Bond (3M/ESPE); Group III: Perma Seal (Ultradent); Group IV: Heliobond (Vivadent); Group V: Biscover LV (Bisco); Group VI: Bioforty (Biodinâmica). The samples were then immersed in 2 % aqueous methylene blue solution for 48 hours, and thermocycled 100 times from 5 ºC to 55 ºC. The obtained specimens were ground in a bucco-palatal orientation to reach the medial plane, and observed under a stereoscopic loupe at 40X. The degree of microleakage was evaluated by assessing the penetration of the dye to the tooth-restoration interface, using a 0 to 3 grading scale. The obtained data were analyzed using the Kruskal-Wallis non-parametric test. Significant differences were observed between all rebonded groups and the control group; no differences were observed among Single Bond, Perma Seal and bioforty, or between Heliobond and Biscover LV. It would seem convenient to apply a surface sealant over composite restorations to improve marginal integrity and reduce microleakage.

RESUMEN: La contracción de polimerización de los composites puede generar fuerzas que determinan la formación de microbrechas en la interfase resina-esmalte y filtración marginal. El objetivo de este trabajo fue evaluar la influencia de los sellantes de superficie, en restauraciones de composite, sobre la microfiltración. Se utilizaron 30 premolares superiores e inferiores, libres de caries, donde se realizaron preparaciones oclusales amelodentinarias que fueron obturadas con One Coat Bond SL y Brilliant New Generation (Coletene), siguiendo las indicaciones del fabricante y pulidas adecuadamente. Luego las muestras se distribuyeron aleatoriamente en seis grupos, según los materiales experimentales: Grupo I (Control), Grupo II: Single Bond (3M/ESPE), Grupo III: Perma Seal (Ultradent), Grupo IV: Heliobond (Vivadent), Grupo V: Biscover LV (Bisco), Grupo VI: bioforty (biodinámica). Posteriormente las piezas fueron sometidas a ciclaje térmico por 100 ciclos entre 5 ºC y 55 ºC, sumergidas en una solución acuosa de azul de metileno al 2 % durante 48 horas y desgastadas en sentido V-P, hasta el plano medial, para ser observadas con lupa estereoscópica a 40 X. El grado de filtración se evaluó por la penetración del colorante en la interfase diente-restauración en una escala de O a 3. Los datos obtenidos fueron analizados mediante la muestra no paramétrica de Kruskal-Wallis. Se encontraron diferencias significativas de todos los grupos con respecto al grupo control (p= 0,0167), no existiendo significación entre Single Bond, Perma Seal y bioforty ni entre Heliobond y Biscover LV. En restauraciones de composite, sería conveniente la aplicación de sellantes de superficie para mejorar la integridad marginal y disminuir la microfiltración.

Experimental Minimum-Error Quantum-State Discrimination in High Dimensions.

Quantum mechanics forbids perfect discrimination among nonorthogonal states through a single shot measurement. To optimize this task, many strategies were devised that later became fundamental tools for quantum information processing. Here, we address the pioneering minimum-error (ME) measurement and give the first experimental demonstration of its application for discriminating nonorthogonal states in high dimensions. Our scheme is designed to distinguish symmetric pure states encoded in the transverse spatial modes of an optical field; the optimal measurement is performed by a projection onto the Fourier transform basis of these modes. For dimensions ranging from D=2 to D=21 and nearly 14 000 states tested, the deviations of the experimental results from the theoretical values range from 0.3% to 3.6% (getting below 2% for the vast majority), thus showing the excellent performance of our scheme. This ME measurement is a building block for high-dimensional implementations of many quantum communication protocols, including probabilistic state discrimination, dense coding with nonmaximal entanglement, and cryptographic schemes.

The evolution of the medical workforce in Cape Verde since independence in 1975.

BACKGROUND: Cape Verdean doctors have always graduated abroad. The first experience of pre-graduate medical education in Cape Verde begun in October 2015. Counting how many doctors Cape Verde has, knowing who they are, and knowing how they are distributed are very important to help fine-tune the medical training. The aim of this study is to analyze the evolution of the medical workforce in Cape Verde to support medical education implementation. METHODS: Secondary data on doctors, from July 1975 until December 2014, collected from the Ministry of Health, were entered into an SPSS 20 database and studied by a simple descriptive statistical analysis. RESULTS: The database included data on 401 medical doctors. There was a predominance of females (n = 218; 54.4%). The overwhelming majority (n = 378; 94.3%) graduated from 5 of the 17 countries that contributed to the training of Cape Verdean doctors. All the islands of this archipelago country contributed to the 324 (80.8%) doctors born in the country. Of the 272 doctors still active in December 2014, 119 (43.6%) were general practitioners and 153 (56.4%) had specialized in one of the 31 specialties. The national ratio of doctors per 10 000 inhabitants was 5.25, but the reality varied significantly among islands. About one third of the doctors (n = 86; 32%) were at the primary care level, 38 (14%) at the secondary care level, and 144 (52%) in central hospitals. In 2053, all active physicians in 2014 will already be retired. CONCLUSIONS: This is a unique study of the evolution of the medical workforce of a country over 40 years, from the first day of independence. The study illustrates the importance of international collaborations, particularly of Cuba, in sustaining the medical workforce in Cape Verde. It is an example of how this collaboration was used to equip the country with doctors in an increasingly more equitable distribution across all islands. The study further illustrates the progressive feminization of the medical workforce. The study clarifies the effort required from the emerging medical faculty to supply the national health system with the needed number of doctors.

Evaluation of oral microbiota in undernourished and eutrophic children using checkerboard DNA-DNA hybridization.

The aim of this study was to evaluate the relationship among nutritional status, gingival health and the composition of oral microbiota in children of a public school from a very poor area of San Miguel de Tucuman. Forty-five children ranging in age from 6 to 14 years old, 13 males and 32 females were studied. Twenty of these children were undernourished (Lejarraga-Morasso Table) and twenty-five were eutrophic. A clinical study that included DMF and dmf indexes, Löe Silness Plaque Index and bleeding on probing was performed. For microbiological study, saliva samples without stimulation were taken; aliquots of them were immediately placed in TAE buffer pH 7.6, adding NaOH (N and keeping at -70 °C until processed by checkerboard DNA-DNA hybridization method to check the presence of 40 oral microorganism species. Positive bleeding on probing was present in more than 80% of children, without significant differences between eutrophic and undernourished groups. Same result were obtain for the other clinical indexes (p > 0.05, Two Way ANOVA). Significant differences were found for some oral microorganism species, with a higher percentage of undernourished children harboring them. That was the case of S. gordonii (p < 0.05), Capnocitophaga gingivalis and C. ochraceae (p < 0.01 and p < 0.10, respectively), F. nucleatum ss nucleatum (p < 0.05), P. nigrescens (p < 0.10), Campylobacter gracilis (p < 0,05), and T. denticola (p < 0.10, multiple logistic regression). Significant differences were also found between children groups for E. saborreum (p < 0.001), P. acnes (p < 0.10), G. morbillorum (p < 0.05) and L. buccalis (p < 0.10). Gingivitis and bleeding on probing would not be related to nutritional status in the groups of children studied. There were significant differences for the presence of some of the main periodontal pathogen species between eutrophic and undernourished children. It would be important to study the meaning of significant differences found for the other microorganisms more deeply.