Measurements of neutrino oscillation parameters from the T2K experiment using 3.6×1021 protons on target.

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7(16.3)×1020 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7×1020 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin2θ13 and the impact of priors on the δCP measurement. Both analyses prefer the normal mass ordering and upper octant of sin2θ23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin2θ13 from reactors, sin2θ23=0.561-0.032+0.021 using Feldman-Cousins corrected intervals, and Δm322=2.494-0.058+0.041×10-3eV2 using constant Δχ2 intervals. The CP-violating phase is constrained to δCP=-1.97-0.70+0.97 using Feldman-Cousins corrected intervals, and δCP=0,π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2σ credible level using a flat prior in δCP, and just below 2σ using a flat prior in sinδCP. When the external constraint on sin2θ13 is removed, sin2θ13=28.0-6.5+2.8×10-3, in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

A nearby transiting rocky exoplanet that is suitable for atmospheric investigation.

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

Bacteria associated with periodontal disease are also increased in health.

BACKGROUND: The objective of this cross-sectional clinical study was to analyze the differences in the microbiome in gingival sulci of adult patients in the presence or absence of chronic periodontitis. MATERIAL AND METHODS: Patients with or without periodontal disease were included in this cross-sectional study. Subgingival biofilm samples were collected and analyzed by 16S massive pyrosequencing. Functional analyses were also performed. RESULTS: A total of 15 phyla, 154 genera and 351 species were detected globally. Differences between disease and non-disease samples were observed in all taxonomical levels which suggest functional profile changes in the community. It was found that the main species associated with non-disease samples were reduced in disease but not completely suppressed. Analysis of the functional potential of the biofilms revealed a significantly higher activity related to endocytosis and phosphatidylinositol signaling in the disease group but lower cell adhesion molecules. CONCLUSIONS: Specific differences between health and disease suggest functional profile changes in the community, although bacteria associated with periodontal disease are also increased in health. Transcriptome studies should be conducted to confirm and deepen metabolic dysfunctions.

A giant exoplanet orbiting a very-low-mass star challenges planet formation models.

Surveys have shown that super-Earth and Neptune-mass exoplanets are more frequent than gas giants around low-mass stars, as predicted by the core accretion theory of planet formation. We report the discovery of a giant planet around the very-low-mass star GJ 3512, as determined by optical and near-infrared radial-velocity observations. The planet has a minimum mass of 0.46 Jupiter masses, very high for such a small host star, and an eccentric 204-day orbit. Dynamical models show that the high eccentricity is most likely due to planet-planet interactions. We use simulations to demonstrate that the GJ 3512 planetary system challenges generally accepted formation theories, and that it puts constraints on the planet accretion and migration rates. Disk instabilities may be more efficient in forming planets than previously thought.

A candidate super-Earth planet orbiting near the snow line of Barnard's star.

Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known2,3 and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging4-6, astrometry7,8 and direct imaging9, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard's star, making it an excellent target for direct imaging and astrometric observations in the future.

Continued propagation of the CRF19_cpx variant among HIV-positive MSM patients in Spain.

Objectives: The HIV-1 CRF19_cpx genetic form has been recently associated with greater pathogenicity. We used CoRIS, a national cohort of 31 reference hospitals in Spain, to investigate the current epidemiological situation of this variant in Spain. Patients and methods: We analysed 4734 naive HIV-1-positive patients diagnosed during the 2007-15 period with an available pol gene sequence in the CoRIS resistance database. HIV-1 CRF19_cpx was ascribed through REGA3.0 and confirmed by a phylogenetic analysis. We analysed the presence of the transmission clusters of HIV-1 CRF19_cpx by maximum likelihood [with the randomized accelerated maximum likelihood (RAxML) program] and the time to the most recent common ancestor using Bayesian inference (BEAST, v. 1.7.5). Results: Nineteen patients were infected with CRF19_cpx: all were male, they had a mean age of 42.9 years (95% CI: 36.4-52.5 years), the majority were MSM [n = 18 (95%)] and of Spanish nationality [n = 16 (84.2%)] and they had high CD4+ T cell counts (∼415 cells/mm3). Fifteen patients were grouped into four different transmission clusters: two clusters (two patients each) grouped the patients from Valencia and another cluster grouped one patient from Madrid and another from Seville. We found a larger cluster that grouped nine patients from southern Spain (Malaga and Seville), of which six presented mutation G190A. We estimated the origin of all the transmission clusters to take place between 2009 and 2010. Conclusions: We demonstrate that this variant has spread in Spain in recent years among young HIV-positive MSM and we note a recent expansion in southern Spain in patients who carry mutation G190A. We alert healthcare managers to enhance preventive measures to prevent the continuous spread of HIV-1 CRF19_cpx.

The cobas® HCV GT is a new tool that accurately identifies Hepatitis C virus genotypes for clinical practice.

OBJECTIVE: We aimed to evaluate the correct assignment of HCV genotype/subtypes 1a and 1b by cobas® HCV genotyping (GT) assay (Roche Molecular Diagnostics) compared with nonstructural protein 5B (NS5B) sequencing. PATIENTS AND METHODS: Clinical samples from 153 patients submitted for HCV genotyping were studied. After genotyping with the cobas® HCV GT, sequencing of a 387 bp fragment in the NS5B gene and phylogenetic analysis was employed to compare genotyping results. Major discrepancies were defined as differences in the assigned genotype by cobas® HCV GT and NS5B sequencing (including genotype 1 subtypes 1a and 1b misclassification). RESULTS: Overall agreement between the cobas® HCV GT and NS5B sequencing was 98%; all the 1a, 1b, 2, 3 and 4 genotypes identified by cobas® HCV GT were concordant with NS5B sequencing. Three samples tested "indetermined" by cobas® HCV GT assay and were genotyped as 1a, 3a, and 4d by NS5B sequencing. CONCLUSSION: These results indicate that the cobas® HCV GT assay correctly identifies HCV genotypes, and points out the importance of additional methods based on DNA sequencing for resolving indeterminate results.

Preferred spoken language mediates differences in neuraxial labor analgesia utilization among racial and ethnic groups.

INTRODUCTION: The aims of this study were to assess racial/ethnic disparities for neuraxial labor analgesia utilization and to determine if preferred spoken language mediates the association between race/ethnicity and neuraxial labor analgesia utilization. METHODS: We performed a retrospective cohort study of 3129 obstetric patients who underwent vaginal delivery at a tertiary care obstetric center. Bivariate analyses and multivariate logistic regression models were used to assess the relationships between race/ethnicity, preferred spoken language and neuraxial labor analgesia. RESULTS: Hispanic ethnicity (adjusted OR 0.77, 95% CI 0.61-0.98) and multiparity (adjusted OR 0.59, 95% CI 0.51-0.69) were independently associated with a reduced likelihood of neuraxial labor analgesia utilization. When preferred spoken language was controlled for, the effect of Hispanic ethnicity was no longer significant (adjusted OR 0.84, 95% CI 0.66-1.08) and only non-English preferred spoken language (adjusted OR 0.82, 95% CI 0.67-0.99) and multiparity (adjusted OR 0.59, 95% CI 0.51-0.69) were associated with a reduced likelihood of neuraxial labor analgesia utilization. CONCLUSIONS: This study provides evidence that preferred spoken language mediates the relationship between Hispanic ethnicity and neuraxial labor analgesia utilization.

Meson-exchange currents and quasielastic antineutrino cross sections in the superscaling approximation.

We evaluate quasielastic double-differential antineutrino cross sections obtained in a phenomenological model based on the superscaling behavior of electron scattering data and estimate the contribution of the vector meson-exchange currents in the two-particle-two-hole sector. We show that the impact of meson-exchange currents for charge-changing antineutrino reactions is much larger than in the neutrino case.

Relativistic descriptions of final-state interactions in charged-current quasielastic neutrino-nucleus scattering at MiniBooNE kinematics.

The results of two relativistic models with different descriptions of the final-state interactions are compared with the MiniBooNE data of charged-current quasielastic cross sections. The relativistic mean field model uses the same potential for the bound and ejected nucleon wave functions. In the relativistic Green's function model, the final-state interactions are described in the inclusive scattering consistently with the exclusive scattering using the same complex optical potential. The relativistic Green's function results describe the experimental data for total cross sections without the need to modify the nucleon axial mass.

Echocardiographic study of structure and functional cardiac profile of football referees.

AIM: The aim of this study was to analyze, through echocardiography, the structure and functional cardiac profile of national category Spanish soccer referees. METHODS: The sample consisted of 54 licensed referees, who belonged to the Football Inter-Insular Federation of Las Palmas. The sample presented a mean age of 28.52 ± 6.39 years, a height of 1.76 ± 0.07 m, a body mass of 77.26 ± 10.74 kg and a Body Mass Index of 24.90 ± 2-73 kg/m2. The diastolic and systolic dimensions of the left ventricle were 50.03 ± 4.79 mm and 33.74 ± 5.23 mm, respectively. The thicknesses of the interventricular septum and the posterior wall of the left ventricle were 9.77 ± 1.53 mm and 9.47 ± 1.54 mm, respectively. The left ventricular mass was 112.80 ± 26.53 g/m2, the diastolic volume of the left ventricle 135.09 ± 39.63 mL and the ejected volume 47.34 ± 12.44 mL/m2. RESULTS: This study shows that the echocardiographic profile of football referees is characterized by presenting an increase in the left ventricular mass caused by an increase of the cardiac chambers and a normal systolic and diastolic function. The values obtained by football referees were higher than those found in sedentary people and lower than in professional football players. CONCLUSION: These differences may be due to the different physical training workloads employed by football players and referees.

Superscaling predictions for neutral current quasielastic neutrino-nucleus scattering.

The application of superscaling ideas to predict neutral-current (NC) quasielastic (QE) neutrino cross sections is investigated. The relativistic impulse approximation (RIA) using the same relativistic mean field potential (RMF) for both initial and final nucleons - a model that reproduces the experimental (e,e(')) scaling function - is used to illustrate our findings. While NC reactions are apparently not well suited for scaling analyses, to a large extent, the RIA-RMF predictions do exhibit superscaling. Independence of the scaled response on the nuclear species is very well fulfilled. The RIA-RMF NC superscaling function is in good agreement with the experimental (e,e(')) one. The idea that electroweak processes can be described with a universal scaling function, provided that mild restrictions on the kinematics are assumed, is shown to be valid.

Quasielastic charged-current neutrino-nucleus scattering.

We provide integrated cross sections for quasielastic charged-current neutrino-nucleus scattering. Results evaluated using the phenomenological scaling function extracted from the analysis of experimental (e, e') data are compared with those obtained within the framework of the relativistic impulse approximation. We show that very reasonable agreement is reached when a description of final-state interactions based on the relativistic mean field is included. This is consistent with previous studies of differential cross sections which are in accord with the universality property of the superscaling function.

Detección de problemas en pacientes geriátricos con fractura de cadera. Importancia de la colaboración entre traumatólogo y geriatra / Detection of health conditions in elderly patients with a hip fracture. Importance of collaboration between orthopedic and geriatric specialists

Objetivo. Evaluar el beneficio que proporciona un Equipo Consultor Geriátrico (ECG) a los pacientes geriátricos que ingresan con fractura de cadera en cuanto a la detección de problemas clínicos. Material y método. Estudio prospectivo y controlado que compara dos grupos: los pacientes manejados por el ECG y los que no conoció dicho equipo. Resultados. Fueron estudiados 449 pacientes, con una edad media de 83 años y el 80% mujeres. El ECG detectó más antecedentes personales (5,4 frente a 3,3) y más síndromes geriátricos previos (2 frente 0,4). A lo largo del ingreso el ECG detectó más complicaciones (3,8 frente a 0,4), más nuevos diagnósticos (2,1 frente a 0,4) y más síndromes geriátricos (3,6 frente a 0,5). Las diferencias resultaron significativas en los siguientes problemas: anemia, desnutrición, estreñimiento, delirium, osteoporosis, úlceras por presión, demencia, déficit sensoriales e incontinencia. Algunos de los datos recogidos nos sugieren que pudo haber diagnósticos no detectados en el grupo control. Conclusiones. La revisión diaria por parte del ECG de los pacientes ofrece una evaluación más completa y reduce la probabilidad de infradiagnóstico de problemas clínicos importantes. La colaboración entre traumatólogo y geriatra da como resultado un manejo del paciente más efectivo

Purpose. To assess the benefits of a Geriatric Consultant Team (GCT) to detect health conditions in elderly patients hospitalized for a hip fracture. Materials and methods. This was a prospective controlled study that compared two groups: patients under the care of a GCT and those not under the care of a GCT. Results. A total of 449 patients were studied; mean age 83 years; 80% women. The GCT detected more incidents in clinical records (5.4 compared to 3.3), and more previous geriatric syndromes (2 compared to 0.4). During hospitalization the GCT detected a higher rate of complications (2.1 compared to 0.4) and more geriatric syndromes (3.6 compared to 0.5). Significant differences were seen in the following conditions: anemia, malnutrition, constipation, delirium, osteoporosis, bedsores, dementia, sensory deficits and incontinence. Some of the data collected suggested that there might have been non-detected health conditions in the control group. Conclusions. The GCT reviewed patients daily, which resulted in a more complete assessment and a reduction in the probability of under-diagnosing significant clinical conditions. More effective patient care is achieved when Geriatric and Orthopedic Specialists work together (AU)

Valoración de la composición corporal mediante cienantropometría e impedancia en escolares canarios / Assessment of body composition among school children from the Canary Islands by means of kinanthropometry and impedance

Antecedentes: La evolución de los estudios cineantropométricos ha permitido determinar que para obtener la composición corporal de un sujeto sólo sea necesario estudiar los componentes graso y muscular. El presente estudio tiene por objetivo valorar la composición corporal en escolares canarios mediante cineantropometría e impedancia, y comparar ambas técnicas de medida. Métodos: Diseño: estudio transversal. Sujetos: escolares canarios de entre 6 y 16 años de edad residentes en Gran Canaria y Tenerife. Selección de la muestra: muestreo, aleatorio estratificado simple, a partir de una población infinita de niños entre 6 y 16 años de edad, con un nivel de significación del 95% y un margen de error del 5%, y de p=q=0,5. El tamaño de la muestra obtenido a justado en función del porcentaje esperado de pérdidas es de 549 alumnos. Tratamiento estadístico: paquete informático SPSS 11.0. Se considera significativo el valor de p>=0,5. Comparación de los sistemas de medida mediante un modelo de regresión no lineal (método de Marquardt). Resultados: Hemos estudiado a 563 escolares: 254 niños y 309 niñas. Los dos procedimientos tienden a coincidir asintóticamente. El coeficiente de determinación para el porcentajede grasa ( A2) es de 0,93 y paral a masal ibre de grasa el A2 es de 0,63. Conclusiones: El modelo de regresión no lineal aplicado a un programa informático permite estimar la composición corporal corregida mediante datos obtenidos por impedancia, método con buena reproducibilidad a diferencia de la cineantropometría

Background: Kinanthropometric studies affirm that, to assess an individual's body composition, it is only necessary to establish his or her fat and muscle components. The purpose of this study was to assess body composition among school children from the Canary Islands by means of kinanthropometry and impedance, and to compare the two measuringte chniques. Methods: Design: Cross-sectional study. Subjects: Canary Island school children between the ages of 6 and 16 living on Gran Canaria and Tenerife. Sample selection: Stratified simple random sampling, from an infinite population of children between the ages of 6 and 16, with a level of significance of 95% and amargin of error of 5%,assuming that p=q=0.5. The required sample size, after adjustment for expected losses, was 549 school children. Statistical treatment: SPSS 11.0 statistical analysis application. A p value less than or equal to 0.5 was considered significant. The measuring systems were compared by means of a nonlinear regression model (the Marquardtm ethod). Results: We assessed 563 school children: 254 boys and 309 girls. The two procedure stended to coincide asymptotically. The coefficient of determination (A2) was 0.93 for the percentage of body fat and 0.63 for tal-free body mass. Conclusion: The application of the nonlinear regression model to a software application enables the estimation of corrected body composition on the basis of data obtained by means of impedance, which, unlike kinanthropometry, is a method with good reproducibility

[Response of tidal volume to inspiratory time ratio during incremental exercise]. / Respuesta de la relación volumen corriente-tiempo inspiratorio durante un esfuerzo incremental.

OBJECTIVE: There is some debate about the participation of the Hering-Breuer reflex during exercise in human beings. This study aimed to investigate breathing pattern response during an incremental exercise test with a cycle ergometer. Participation of the Hering-Breuer reflex in the control of breathing was to be indirectly investigated by analyzing the ratio of tidal volume (VT) to inspiratory time (tI). SUBJECTS AND METHODS: The 9 active subjects who participated the study followed an incremental protocol on a cycle ergometer until peak criteria were reached. During exercise, VT/ti can be described in 2 phases, separated by activation of the Hering-Breuer reflex (inspiratory off-switch threshold). In phase 1, ventilation increases because VT increases, resulting in a slight decrease in tI, whereas, in phase 2, increased ventilation is due to both an increase in VT and a decrease in tI. RESULTS: The mean (SD) inspiratory off-switch threshold was 84.6% (6.3%) when expressed relative to peak VT (mean, 3065 [566.8] mL) and 48% (7.2%) relative to the forced vital capacity measured by resting spirometry. The inspiratory off-switch threshold correlated positively (r=0.93) with the second ventilatory threshold, or respiratory compensation point. CONCLUSIONS: The inspiratory off-switch threshold and VT/ti are directly related to one another. The inspiratory off-switch threshold was related to the second ventilatory threshold, suggesting that the Hering-Breuer reflex participates in control of the breathing pattern during exercise. Activation of the reflex could contribute by signaling the respiratory centers to change the breathing pattern.

Respuesta de la relación volumen corriente-tiempo inspiratorio durante un esfuerzo incremental / Response of tidal volume to inspiratory time ratio during incremental exercise

Objetivo: La participación del reflejo de Hering-Breuer durante el ejercicio en seres humanos es objeto de discusión. El propósito del presente trabajo ha sido estudiar la respuesta del patrón respiratorio durante un esfuerzo incremental en cicloergómetro para comprobar, de forma indirecta, mediante el análisis de la relación volumen corriente-tiempo inspiratorio (VT/tI), la participación del reflejo de Hering-Breuer en el control de la respiración. Sujetos y métodos: Han participado en el estudio 9 sujetos activos que han llevado a cabo un protocolo incremental en cicloergómetro hasta alcanzar criterios máximos. Se ha comprobado que la relación VT/tI durante el ejercicio presenta 2 fases con un punto de ruptura, denominado punto de ruptura Hering-Breuer (PHB): fase I, donde el incremento de la ventilación se produce a expensas del aumento del VT con ligero descenso del tI, y fase II, durante la cual el incremento ventilatorio se produce tanto por el aumento del VT como por el descenso del tI. Resultados: En el estudio, el PHB se alcanzaba a un valor medio (± desviación estándar) del 84,6 ± 6,3% respecto al máximo valor de VT (3.065 ± 566,8 ml) y de un 48 ± 7,2% respecto al valor de la capacidad vital forzada medida en la espirometría de reposo. El PHB se relacionó de forma positiva (r = 0,93) con el umbral ventilatorio 2 o umbral de compensación respiratoria. Conclusiones: Existe relación directa entre el PHB y VT/tI. El PHB se relaciona con el umbral ventilatorio 2, de manera que intervendría en el control del patrón ventilatorio durante el ejercicio. La entrada en funcionamiento del reflejo podría contribuir informando a los centros respiratorios para llevar a cabo el cambio de patrón ventilatorio

Objective: There is some debate about the participation of the Hering-Breuer reflex during exercise in human beings. This study aimed to investigate breathing pattern response during an incremental exercise test with a cycle ergometer. Participation of the Hering-Breuer reflex in the control of breathing was to be indirectly investigated by analyzing the ratio of tidal volume (VT) to inspiratory time (tI). Subjects and methods: The 9 active subjects who participated the study followed an incremental protocol on a cycle ergometer until peak criteria were reached. During exercise, VT/ti can be described in 2 phases, separated by activation of the Hering-Breuer reflex (inspiratory off-switch threshold). In phase 1, ventilation increases because VT increases, resulting in a slight decrease in tI, whereas, in phase 2, increased ventilation is due to both an increase in VT and a decrease in tI. Results: The mean (SD) inspiratory off-switch threshold was 84.6% (6.3%) when expressed relative to peak VT (mean, 3065 [566.8] mL) and 48% (7.2%) relative to the forced vital capacity measured by resting spirometry. The inspiratory off-switch threshold correlated positively (r=0.93) with the second ventilatory threshold, or respiratory compensation point. Conclusions: The inspiratory off-switch threshold and VT/ti are directly related to one another. The inspiratory off-switch threshold was related to the second ventilatory threshold, suggesting that the Hering-Breuer reflex participates in control of the breathing pattern during exercise. Activation of the reflex could contribute by signaling the respiratory centers to change the breathing pattern

Superscaling in charged current neutrino quasielastic scattering in the relativistic impulse approximation.

Superscaling of the quasielastic cross section in charged-current neutrino-nucleus reactions at energies of a few GeV is investigated within the framework of the relativistic impulse approximation. Several approaches are used to describe final-state interactions and comparisons are made with the plane-wave approximation. Superscaling is very successful in all cases. The scaling function obtained using a relativistic mean field for the final states shows an asymmetric shape with a long tail extending towards positive values of the scaling variable, in excellent agreement with the behavior presented by the experimental scaling function.

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[An adrenaline-induced vasospasm as the form of presentation of variant angina]. / Vasoespasmo inducido por adrenalina como forma de presentación de una angina variante.

A 41-year-old-man without previous ischemic heart disease, developed a severe anaphylactic reaction. After administration of epinephrine (0.5 mg) the patient complained of chest pain. The electrocardiogram showed an elevation of ST segment in inferior leads. Myocardial necrosis was ruled out. Coronary arteriography disclosed normal coronary arteries. Eight months later, the patient developed severe chest pain during physical activity. ST elevation was again seen in inferior leads. ECG changes disappeared, when sublingual nitroglycerin was administered. A diagnosis of vasospastic angina was made. Exercise test was negative, during treatment with calcium-blocking agents. The patient subsequently remain free of symptoms taking medication. The physiological mechanisms of vasospastic angina and precipitating factors are discussed.