Understanding Motivation for Physical Activity Charity Event Participation.

Objectives: The positive health benefits of regular physical activity (PA) are widely known, yet PA levels remain low in the general population and those with neurological conditions like multiple sclerosis (MS). The goal of this study was to use the lens of behavioral economics to explore PA motivation for participation in PA-based MS charity fundraising events to elucidate the relationship between behavioral economics constructs and motivation. Methods: Mixed-methods survey data were collected from 114 individuals (47 diagnosed with MS; 67 without MS) who had participated in a PA-based MS charity fundraiser event. Results: Quantitative data showed 23 (41.8%) of participants without MS, and 16 (43.2%) of participants living with MS cited fundraising for MS as the primary reason for participation. Open-ended responses revealed behavioral economic constructs of framing, social support, and individual positive biases were key factors contributing to increased motivation for participation. Conclusion: Habit formation for PA behaviors may emerge due to personal biases (perceived importance of fundraising) and a sense of relatedness. Involvement in MS charity events may alter social norms, frame events as enjoyable, and foster a sense of community, thereby increasing the likelihood of continued participation.

Preparation and in vitro evaluation of radiolabeled HA-PLGA nanoparticles as novel MTX delivery system for local treatment of rheumatoid arthritis.

Radiosynovectomy is a technique used to decrease inflammation of the synovial tissue by intraarticular injection of a ß-emitting radionuclide, such as 177Lu, which is suitable for radiotherapy due to its decay characteristics. Drug-encapsulating nanoparticles based on poly lactic­co­glycolic acid (PLGA) polymer are a suitable option to treat several arthritic diseases, used as anti-inflammatory drugs transporters of such as methotrexate (MTX), which has been widely used in the arthritis treatment (RA), and hyaluronic acid (HA), which specifically binds the CD44 and hyaluronan receptors overexpressed on the inflamed synovial tissue cells. The 1,4,7,10­Tetraazacyclododecane­1,4,7,10­tetraacetic acid (DOTA) was used as complexing agent of Lutetium-177 for radiotherapy porpoises. The aim of this research was to synthesize 177Lu-DOTA-HA-PLGA(MTX) as a novel, smart drug delivery system with target-specific recognition, potentially useful in radiosynovectomy for local treatment of rheumatoid arthritis. The polymeric nanoparticle system was prepared and chemically characterized. The MTX encapsulation and radiolabelling were performed with suitable characteristics for its in vitro evaluation. The HA-PLGA(MTX) nanoparticle mean diameter was 167.6 nm ±â€¯57.4 with a monomodal and narrow distribution. Spectroscopic techniques demonstrated the effective conjugation of HA and chelating agent DOTA to the polymeric nanosystem. The MTX encapsulation was 95.2% and the loading efficiency was 6%. The radiochemical purity was 96 ±â€¯2%, determined by ITLC. Conclusion: 177Lu-DOTA-HA-PLGA(MTX) was prepared as a biocompatible polymeric PLGA nanoparticle conjugated to HA for specific targeting. The therapeutic nanosystem is based on bi-modal mechanisms using MTX as a disease-modifying antirheumatic drug (DMARD) and 177Lu as a radiotherapeutic component. The 177Lu-DOTA-HA-PLGA(MTX) nanoparticles showed properties suitable for radiosynovectomy and further specific targeted anti-rheumatic therapy.

Independent estimates of marine population connectivity are more concordant when accounting for uncertainties in larval origins.

Marine larval dispersal is a complex biophysical process that depends on the effects of species biology and oceanography, leading to logistical difficulties in estimating connectivity among populations of marine animals with biphasic life cycles. To address this challenge, the application of multiple methodological approaches has been advocated, in order to increase confidence in estimates of population connectivity. However, studies seldom account for sources of uncertainty associated with each method, which undermines a direct comparative approach. In the present study we explicitly account for the statistical uncertainty in observed connectivity matrices derived from elemental chemistry of larval mussel shells, and compare these to predictions from a biophysical model of dispersal. To do this we manipulate the observed connectivity matrix by applying different confidence levels to the assignment of recruits to source populations, while concurrently modelling the intrinsic misclassification rate of larvae to known sources. We demonstrate that the correlation between the observed and modelled matrices increases as the number of observed recruits classified as unknowns approximates the observed larval misclassification rate. Using this approach, we show that unprecedented levels of concordance in connectivity estimates (r = 0.96) can be achieved, and at spatial scales (20-40 km) that are ecologically relevant.

[Biatrial re-synchronization in the treatment of paroxysmal atrial fibrillation. 3- and 4-chamber pacemaker]. / Resincronización biatrial en el tratamiento de la fibrilación atrial paroxística. Marcapaso tres y cuatro cámaras.

The reason for multisite pacing is to correct atrial and ventricular electrical and mechanical asynchrony found in paroxysmal atrial fibrillation (PAF) and dilated cardiomyopathy. We report the first two cases in Mexico treated with biatrial pacing for PAF. The first was treated with a three chamber pacemaker and the other with a four chamber pacemaker. The first patient was a young man with uncontrolled ventricular rate in whom the atrioventricular conduction was modified with radiofrequency energy to control ventricular rate during atrial fibrillation. The second patient was a woman with corrected transposition of the great arteries, left ventricular ejection fraction (LVEF) of 30% and complete heart block. The pacing modalities were DDD for the first patient and DDDR for the second, both with sleep rate and auto mode switching. The atria were paced in right appendage and the left through the coronary sinus. PAF episodes were, found only in the first patient but were decreased in number and duration. The LVEF and functional class improved in the patient with biatrial and ventricular resynchronization. We conclude that biatrial pacing is effective in PAF.

[Trichamber pacing in dilated myocardiopathy. TTDR pacing?]. / Estimulación tricameral en la miocardiopatía dilatada. Modo de estimulación TTDR?

This article describes the first case in Mexico city that received a three chamber pacing system. A 40 year-old man with dilated cardiomyopathy with variant cardiac rhythm and bradycardia. The three leads were introduced by right subclavian approaches. The right chamber leads were placed in atrial's appendage and in the right ventricular outflow tract and the last one was placed in the great cardiac vein. The two ventricular lead were connected a Y-connector to the ventricular channel of a standard bipolar DDDR pacemaker. The right ventricular lead was connected to the distal pole (anode) and the left ventricular lead to the proximal pole (cathode). Eight days later, the patient's clinical status improved, his functional class improved from IV to II and his left ventricular ejection fraction increased from 30% to 35% by conventional ventriculography. In this type of patients the improvement in cardiac output is this result an of increase in left ventricular filling, reduced mitral and tricuspid regurgitation a better synchronization of ventricular contraction. Multisite pacing has added a mayor complexity to contemporary pacing and a modification of the standard pacer-maker code should be considered to accommodate multisite pacing. The letter in the first and second position might be T (three) or F (four) according to number of pacing chamber and also the letter "t" may be suitable to designate trigger in the third position. We conclude that implant of three chamber pacing in patients with dilated cardiomyopathy is technically feasible. An improvement in the patient's condition may be obtained and a modification in standard pacemaker code is necessary.

Spread of Ergot of Sorghum (Claviceps africana) in Central Mexico.

By late August 1997, sorghum ergot (Claviceps africana Frederickson, Mantle & De Milliano) had not been detected in the Bajio area in central Mexico, the second-largest sorghum (Sorghum bicolor (L.) Moench) producing area in the country, despite earlier 1997 reports of the disease in the adjacent states of San Luis Potosi, Michoacan, and Jalisco. A mid-September survey was conducted in el Bajio, primarily in the state of Guanajuato, and adjacent areas in the states of Michoacan and Jalisco. Infected sorghum heads showing ergot symptoms of honeydew and white secondary sporulation were observed in commercial grain and hybrid seed fields in all three states. Environmental conditions, late summer rains and early low temperatures promoting abundant dew, as well as extended periods of sorghum blooming, contributed to a low and delayed incidence of ergot in Guanajuato. In Michoacan and Jalisco the higher relative humidity and rainfall (around 750 ml) probably contributed to the observed epidemic of ergot. Johnsongrass (Sorghum halepense (L.) Pers.) florets also showed ergot symptoms. Macroconidia in honeydew were hyaline, oblong to oval, slightly constricted at the center, with an average size of 15 × 7 µm, agreeing with the given description of Sphacelia sorghi McRae (2), the anamorph stage of C. africana. No sclerotia were found on any host. Ergot control in this region of Mexico is being attempted by chemical means and burning of heads, even in commercial fields with minimal incidence of ergot. This report of ergot spread complements an earlier note describing the initial detection of the disease in Tamaulipas, the largest sorghum-producing state in Mexico (1). References: (1) J. Aguirre R. et al. Plant Dis. 81:831, 1997. (2) D. E. Frederickson et al. Mycol. Res. 95:1101, 1991.

[Transtelephonic electrocardiography in Mexico. A report of the first 3434 cases]. / La electrocardiografía transtelefónica en México. Reporte de los primeros 3434 casos.

The transtelephonic electrocardiographic system started in the 70's and it was used mainly in the study of heart disease, cardiac arrhythmias, syncope and sudden death. This report, include 3434 electrocardiogram (ECG) of patients whom visit the emergency room at the General Hospital and private clinic, using three different forms of transtelephonic monitors. The total population were 1715 males and 1719 females with average age of 52.2 +/- 28.8 years. 26.9% had was present in history of systemic hypertension, non-insulin dependent diabetes 12.3% and myocardial ischemic disease in 5.3%. The main ECG indications were chest pain 38.7%, most of them atypical angina, palpitations in 6.9% and dyspnea in 6.5%. 50.1% of the ECG were abnormal. The most important diagnosis were: tachyarrhythmias (25.2%), intraventricular conduction abnormalities (17.7%), myocardial ischemic disease (16%), and premature ventricular and supraventricular beats (11.6%). We concluded that the transtelephonic electrocardiographic system is a very useful method, and available now in Mexico. We detected a high percentage of electrocardiographic abnormalities, it was possible to give the right diagnosis of arrhythmias, acute myocardial infarction, old infarction, and to evaluate the pacemaker functionality. Finally, it helped to get in brief time the diagnosis and treatment in cases of acute myocardial infarction or severe arrhythmias.