Actualización en plasma rico en plaquetas / Platelet rich plasma update

Resumen El plasma rico en plaquetas es un producto derivado de la sangre, rico en péptidos y proteínas de señalización intercelular, así como citoquinas capaces de intervenir en cada una de las etapas de la regeneración de varios tejidos. Principalmente, se le han atribuido efectos antiinflamatorios en diferentes lesiones, así como otros efectos biológicos sobre las células y tejidos. A la fecha, no existe un protocolo estándar de producción o preparación, tampoco se ha descrito una dosis específica; la forma de aplicación es muy variable y depende de la condición por tratar. A pesar de ello, se han visto efectos positivos en campos como: odontología, ortopedia, dermatología, medicina reconstructiva, oftalmología, medicina deportiva, medicina vascular, entre otros. Su regulación es muy diversa a nivel internacional. Aunque hay expectativas con el tratamiento de plasma rico en plaquetas, no hay suficientes ensayos clínicos robustos que brinden un alto nivel de evidencia para validarlo como un tratamiento de rutina frente a determinada condición clínica. Además, no se pueden comparar fácilmente los resultados de diferentes investigaciones, por la variabilidad en el método de preparación y por la falta de homogeneidad en las lesiones tratadas, entre otros factores. Es por lo anterior que resulta necesario desarrollar más investigaciones serias que conlleven al establecimiento de un protocolo estandarizado, así como demostrar la efectividad de este nuevo tratamiento, de forma que se culmine con la implementación de nuevas terapias validadas y autorizadas para garantizar una mejoría real a los pacientes.

Abstract Platelet-rich plasma is a blood-derived product, rich in peptides and intercellular signaling proteins and cytokines capable of intervening in each stage of the regeneration of various tissues. Mainly, it has been attributed anti-inflammatory effects in different lesions, as well as other biological effects on cells and tissues. To date, there is no standard production or preparation protocol, nor has a specific dose been described. The form of application is very variable and depends on the condition to be treated. Despite this, positive effects have been seen in different fields such as: dentistry, orthopedics, dermatology, reconstructive medicine, ophthalmology, sports medicine, vascular medicine among others. Its regulation is very diverse internationally. Although there is a lot of expectation with the treatment of platelet-rich plasma, there are not enough robust clinical trials that provide a high level of evidence to validate it as a routine treatment for a certain clinical condition. In addition, the results of different investigations cannot be easily compared due to the variability in the method of preparation and the lack of homogeneity in the treated lesions, among other factors. It is for this reason that it is necessary to develop more serious investigations that lead to the establishment of a standardized protocol, as well as to demonstrate the effectiveness of this new treatment and culminate with the implementation of new validated and authorized therapies to guarantee a real improvement to the patients.

The effects of strength training on cognitive performance in elderly women.

Aging is a degenerative process marked by recognized functional, physiological, and metabolic impairments, such as dynapenia and diminished cognitive capacity. Therefore, the search for innovative strategies to prevent/delay these physiological and cognitive disorders is essential to guarantee the independence and life quality of an elderly population. The aim of this work is to verify the effect of a 12-week resistance exercise program on the general physical aptitude and cognitive capacities of elderly and sedentary women. Twenty-nine women (65.87±5.69 years) were divided into two groups. The control group was composed of eight elderly women who met the same inclusion criteria of the study and the strength training group was composed of 29 elderly women who were subjected to a resistance exercise program defined by 12 upper and lower limb exercises combined in 3×10 repetitions with 1-minute interval between repetitions and two resting minutes between exercises (three times/week). Weight loads were fixed between 60% and 75% of the apparent 1 repetition maximum, which was estimated by the test of 10 maximum repetitions. The direct curl was performed for upper body strength evaluation with 2.3 kg dumbbells for 30 seconds, whereas the chair test was used for lower body evaluation (total sit-stand movements in 30 seconds). The cognitive capacities of subjects were evaluated by "The Montreal Cognitive Assessment" questionnaire. After 12 weeks, the elderly group showed significant increases in the average upper body strength (58%), lower body strength (68%), and cognitive capacity (19%). The present study demonstrated that regular resistance exercises could provide significant gains on the upper and lower body strength concomitant to positive improvements on cognitive capacities of elderly women, bringing enhanced life quality.

A very luminous magnetar-powered supernova associated with an ultra-long γ-ray burst.

A new class of ultra-long-duration (more than 10,000 seconds) γ-ray bursts has recently been suggested. They may originate in the explosion of stars with much larger radii than those producing normal long-duration γ-ray bursts or in the tidal disruption of a star. No clear supernova has yet been associated with an ultra-long-duration γ-ray burst. Here we report that a supernova (SN 2011kl) was associated with the ultra-long-duration γ-ray burst GRB 111209A, at a redshift z of 0.677. This supernova is more than three times more luminous than type Ic supernovae associated with long-duration γ-ray bursts, and its spectrum is distinctly different. The slope of the continuum resembles those of super-luminous supernovae, but extends further down into the rest-frame ultraviolet implying a low metal content. The light curve evolves much more rapidly than those of super-luminous supernovae. This combination of high luminosity and low metal-line opacity cannot be reconciled with typical type Ic supernovae, but can be reproduced by a model where extra energy is injected by a strongly magnetized neutron star (a magnetar), which has also been proposed as the explanation for super-luminous supernovae.