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21 March 2012

Feeding Your Baby On Demand 'May Contribute to Higher IQ'


— A new study suggests that babies who are breast-fed or bottle-fed to a schedule do not perform academically as well at school as their demand-fed peers. The finding is based on the results of IQ tests and school-based SATs tests carried out between the ages of five and 14, which show that demand-feeding was associated with higher IQ scores. The IQ scores of eight-year-old children who had been demand-fed as babies were between four and five points higher than the scores of schedule-fed children, says the study published in the European Journal of Public Health.

This is the finding from the first ever large-scale study to investigate the long-term outcomes of schedule versus demand-fed babies. The study was carried out by researchers at the Institute for Social and Economic Research (ISER) at the University of Essex, and at the University of Oxford. However, the researchers urged caution in interpreting the findings.
Dr Maria Iacovou, who led the research from ISER, said: "At this stage, we must be very cautious about claiming a causal link between feeding patterns and IQ. We cannot definitively say why these differences occur, although we do have a range of hypotheses. This is the first study to explore this area and more research is needed to understand the processes involved."
Taking into account a wide range of background factors that include parents' educational level, family income, the child's sex and age, maternal health and parenting styles, the research finds that demand-feeding is associated with higher IQ scores at age eight, and this difference is also evident in the results of SATs tests at ages five, seven, 11 and 14. The study found that scheduled feeding times did have benefits for the mothers, however, who reported feelings of confidence and high levels of well-being.
"The difference between schedule and demand-fed children is found both in breastfed and in bottle-fed babies," explains Dr Iacovou.
"The difference in IQ levels of around four to five points, though statistically highly significant, would not make a child at the bottom of the class move to the top, but it would be noticeable. To give a sense of the kind of difference that four or five higher IQ points might make, in a class of 30 children, for example, a child who is right in the middle of the class, ranked at 15th, might be, with an improvement of four or five IQ points, ranked higher, at about 11th or 12th in the class."
The research, funded by the Economic and Social Research Council, is based on data from the Avon Longitudinal Study of Parents and Children (ALSPAC), a child development study of more than 10,000 children born in the early 1990s in the Bristol area.
The research looked at three types of mother and baby pairs: those where the baby was fed to a schedule at four weeks of age, those where the mother tried but did not manage to feed to a schedule, and those that fed on demand.
The children of mothers who had tried to feed to a schedule, but did not, were found to have similar higher levels of attainment in SATs tests and IQ scores as demand-fed babies.
Dr Iacovou said: "This is significant because the mothers who tried but did not manage to feed to a schedule are similar to schedule-feeding mothers in that they tend to be younger, more likely to be single, more likely to be social tenants and likely to be less well-educated or to read.

**Published in "SCIENCE DAILY"

Protein Critical for Tissue Regeneration Discovered



In research published online in the Journal of Cell Science, biology Professor Néstor Oviedo has shown that signaling by a protein called Target of Rapamycin (TOR) -- found in humans and most other mammals -- is crucial for planaria's unique tissue regeneration. Disabling the protein prevents the flatworm's regrowth, a sign that disabling it in abnormal cells could prevent the growth of a cancer.
"It's a new model in which we can study stem cell behavior by manipulating the signaling pathways," Oviedo said.
Researchers have recognized that the TOR protein plays a role in cancer, aging and degenerative diseases, but they haven't figured out how it works.
Oviedo's lab is approaching this question using tiny flatworms known as planaria. Long relegated as a scientific oddity, the planarian is now among the species that could be crucial in understanding the role of stem cells. The worm's ability to repair itself is unparalleled, and its secrets could help combat cancer and degenerative diseases.
For this study, Oviedo's lab disabled the TOR protein in planaria and then amputated parts of the flatworm. Under typical circumstances, the organism would be able to repair itself.
But researchers discovered the planaria's stem cells recognized they needed to regrow tissue but were unable to regenerate it in the correct place and instead formed tissues in abnormal places. This kind of regeneration hasn't been reported before. Additionally, the planaria with the disabled protein were unable to grow, even if nutrients were available.
In addition to stopping cancer, understanding TOR and its role in regulation could lead to the development of medicines to encourage tissue regeneration and to fight degenerative diseases, such as Alzheimer's.
Graduate student Harshani Peiris, who was the lead author on the paper, said the planaria gives researchers the ability to look at the reactions of an entire organism, rather than just looking at cells in a Petri dish.
"We have a cutting-edge look into what's happening at the system level," Peiris said.

**Published in "SCIENCE DAILY"

Fármacos menos eficaces de lo que se cree


Fármacos menos eficaces de lo que se cree
.
Los fármacos antipsicóticos pueden ser menos eficaces de lo que los médicos creen. Al menos eso es lo que sugiere estudio publicado en PLoS Medicine  que afirma que la aparente efectividad clínica de la segunda generación fármacos antipsicóticos utilizados para tratar la esquizofrenia y otras enfermedades psicóticas podría haber sido potenciada por la publicación selectiva de ensayos realizados con estos fármacos revistas médicas -un fenómeno llamado sesgo de publicación-. Este hallazgo es importante ya que los resultados de los ensayos publicados influyen en las decisiones de los médicos a la hora de recetar los fármacos.

Los autores, dirigidos por Erick Turner, de la Oregon Health & Science University en Portland, (EE.UU.), han llegado a estas conclusiones tras revisar 24 ensayos registrados por la FDA previos a la comercialización de ocho antipsicóticos de segunda generación-aripiprazol, iloperidona, la olanzapina, la paliperidona, quetiapina, risperidona, la inyección de risperidona de larga duración, y ziprasidona- y comparar estos estudios con los resultados transmitidos en los artículos publicados en las revistas médicas.

Los autores encontraron que cuatro ensayos de estos previos a la comercialización presentados a la FDA permanecen inéditos, y que todos los ensayos no publicados mostraron resultados negativos: tres mostraron que el nuevo antipsicótico no tenía ninguna ventaja estadísticamente significativa frente a placebo, mientras que un ensayo mostraba que el medicamento era estadísticamente inferior un otro mucho menos costoso.
Fármaco inferior
En cuanto a los estudios publicados, los investigadores vieron que se enfatizaba la eficacia del nuevo medicamento. Por ejemplo, la revisión de la FDA reveló que uno de los nuevos medicamentos, iloperidona, era estadísticamente inferior a tres medicamentos diferentes de la competencia, pero esta información no fue mencionada en los artículos de las revistas correspondientes.

Por otro lado, cuando los autores utilizaron meta-análisis para combinar los datos de prueba y comparar los ocho medicamentos con placebo, se encontraron con que el sesgo de publicación tuvo poco efecto sobre su aparente eficacia en general. Más preocupante, dicen, es que algunos datos negativos no aparecen publicados, lo que puede inducir a error.

Los autores concluyen que «la magnitud del sesgo de publicación en el caso de los antipsicóticos es menor que la identificada previamente en los antidepresivos». Y reclaman más estudios que investiguen el sesgo de publicación en otras clases de fármacos, lo que permitirá crear una base de datos con información más precisa.

**Publicado en "ABC SALUD"

Nuevos estudios demuestran el efecto positivo de la aspirina en cáncer de colon, pulmón y de próstata


Confirmado, una aspirina diaria previene el cáncer y ayuda a tratarlo

La aspirina, el medicamento centenario sigue siendo una caja de sorpresas. Combate la fiebre, el dolor y la inflamación y se ha convertido también en el mejor guardián del corazón. Ya nadie duda de que una aspirina diaria salva vidas al evitar obstrucciones en las arterias que pueden conducir a un infarto. Pero ahí no terminan sus bondades. En los últimos años un goteo de investigaciones han apuntado al ácido acetilsalicílico como una fórmula para prevenir la aparición de tumores, y sobre todo del cáncer de colon. La revista médica «The Lancet» publica ahora tres nuevos estudios que no solo confirman su papel protector sino que avalan su utilidad en el tratamiento de otros tumores, como el cáncer de próstata, pulmón o vejiga. Y todo con un medicamento que apenas supera los tres euros por envase. Los tres trabajos pertenecen a la Universidad de Oxford y están dirigidos por el profesor Peter Rothwell.
Este especialista ya había establecido que una aspirina diaria reduce el riesgo de morir por un cáncer a largo plazo. Sin embargo, sus efectos a corto plazo estaban menos claros, especialmente en las mujeres. Tampoco se había determinado cuál era el riesgo-beneficio de consumir durante años una dosis diaria del medicamento. Riesgos como sufrir una hemorragia, uno de los principales peligros de su toma. Las respuestas han llegado con estas nuevas investigaciones.
En uno de estos trabajos se comprobó que el riesgo de morir por cáncer se redujo en un 37% en los participantes que la tomaban de forma diaria. Este efecto positivo se conseguía casi en la misma proporción tanto en hombres como en mujeres.
La posibilidad de sufrir un sangrado o una hemorragia también se detectó, aunque se vio cómo se minimizaba a lo largo del tiempo. Paradójicamente, los autores encontraron que los casos fatales por hemorragia cerebral fueron más bajos en el grupo de pacientes que tomaban aspirina diaria que los del grupo control. Sin el riesgo de hemorragia, el equipo de Peter Rothwell cree que hay más razones para recomendar la toma de una aspirina diaria como fórmula para prevenir la aparición de tumores.
En los otros dos estudios se ofrecen las primeras pruebas de que el medicamento centenario es capaz de evitar la extensión de un tumor a otros órganos y prevenir la temida metástasis. Esto se demostró en pacientes con cáncer de colon, pulmón y de próstata.
La aspiración a prevenir el cáncer con la aspirina viene de lejos. Fue en los años 70 cuando los científicos decidieron pensar que podría haber una causa efecto en aquellos estudios en los que los consumidores de aspirina parecían protegidos frente al cáncer de colon. Aunque los estudios más sesudos empezaron a aparecer diez años más tarde. El efecto protector de la aspirina y del resto de medicamentos con propiedades similares (antiinflamatorios no esteroideos) está en su poder antiinflamatorio y quizá también en su capacidad antiplaquetaria. 

**Publicado en "ABC" 

The Cause and Effect of Migraines


  • "Hormonal changes are a big contributor to the higher female incidence," said Michael A. Moskowitz, MD, Professor of Neurology at Harvard Medical School at the Massachusetts General Hospital in Boston. "There are lines of evidence that support this from lab to clinical evidence and a decrease (although not abolished) incidence in post-menopausal females."
Migraine headaches can vary from person to person, but they typically last from four hours up to 72 hours. Some people get them several times per month, while others experience them much less frequently. Many migraine sufferers report throbbing or pulsating pain on one side of the head, blurred vision, sensitivity to light and sound, nausea, and vomiting. Roughly one in five migraine sufferers experience an aura, or visual or sensory disturbance, before the onset of the headache. Examples of an aura include: flashes of light, loss of vision, zig-zag lines, pins and needles in an arm or leg, and speech and language problems.
Several risk factors have been identified that increase a person's chance of having migraines:
• Family history: A significant majority of migraine sufferers have a family history of migraine attacks. For a person who has one or more first-degree relatives with migraine headaches, the likelihood rises substantially.
• Age: Migraines typically affect people between the ages of 15-55. Most people have had their first attack by 40 years old.
• Gender: Women are more likely to suffer from migraines than men.
• Certain medical conditions: depression, anxiety, stroke, epilepsy, and high blood pressure are all associated with migraine headaches.
• Hormonal changes: Women who suffer from migraines often find that the headaches have a pattern of recurrence just before or shortly after the onset of menstruation. The headaches may also change during pregnancy and/or menopause.
Migraines are vascular headaches but the exact cause is not fully understood. Some researchers believe that migraines occur when there are abnormal changes in the brain. When these changes occur, inflammation causes blood vessels to swell and press on nerves, which can result in pain.
Researchers have learned that certain triggers can set off migraine attacks. These triggers vary from person to person and can include: sleep disturbances, stress, weather changes, low blood sugar, dehydration, bright lights and loud noises, hormonal changes, foods that contain aspartame, foods that contain tyramine (fava beans, aged cheeses, soy products, etc.), caffeine, and alcohol.
Unfortunately, migraines have no known cure, but they can be managed effectively with the help of a health care provider. A variety of drugs can be used for pain relief and for prevention. Lifestyle changes are often recommended to identify and eliminate possible triggers that can set off an attack.
"Until recently there have been no treatments available to treat people who suffer from chronic migraines," said Moskowitz. "Recently, a new medication has become available specifically to treat chronic migraine headaches, called onabotulinumtoxinA (Botox). Chronic migraine sufferers can derive significant benefit from this new form of therapy."
Chronic migraine sufferers have also found relief in certain vitamins and other homeopathic remedies. But patients should check with their doctors for proper treatment protocols.

**Published in "SCIENCE DAILY"

Los nuevas paredes virtuales permiten diseccionar el cerebro en 3D





Los nuevas paredes virtuales permiten diseccionar el cerebro en 3D
Los muros o paredes virtuales son la nueva pantalla tridimensional en la que analizar cualquier objeto o discutir en grupo un diagnóstico. Esta nueva tecnología empieza a funcionar en ámbitos tan diversos como la salud o la industria automovilística. El cerebro humano o el motor del coche se despliegan en 3D en pantallas de más de 130 pulgadas, lo que permite a los especialistas escrutar cada milímetro de la imagen, y agilizar la solución de los problemas.
El grupo de investigación en Modelización, Visualización, Interacción y Realidad Virtual (MOVING) de la Universidad Politècnica de Catalunya acaba de presentar una pared virtual (EsteroWall) de altas prestaciones y de bajo coste para visualizar e interactuar con objetos mediante imágenes estereoscópicas. La instalación funciona con un complejo software desarrollado por el mismo equipo.
La pared virtual se basa en una pantalla de alta resolución de 270 x 200 cm (132 pugladas) donde se proyectan las imágenes. También consta de dos proyectores conectados a un ordenador central (PC), un espejo de reflexión, una pantalla de retroproyección, un dispositivo de posicionamiento y unas gafas de polarización circular para ver en 3D.
Además, dispone de un puntero con distintos botones de control y una linterna mágica virtual, un sistema único hasta ahora en el ámbito de la realidad virtual. Esta linterna es un sistema para visualizar e inspeccionar al mismo tiempo tanto el interior como el exterior del objeto de manera interactiva, lo cual favorece un análisis muy detallado de lo que se quiere inspeccionar. Así, la linterna mágica permite inspeccionar con gran detalle, por ejemplo, cualquier parte del cuerpo humano, desde la piel, pasando por los músculos y las venas, hasta los huesos.
El equipo que ha desarrollado la pared virtual, liderado por la profesora Isabel Navazo, pensó en principio en el uso docente para inspeccionar modelos anatómicos, pero luego descubrieron otras muchas aplicaciones. En el campo médico implica un avance para ayudar al diagnóstico y planificar operaciones quirúrgicas; en el ámbito industrial, facilita y reduce los costes en el diseño cooperativo de prototipos virtuales; en paleontología, permite visualizar con gran detalle piezas fósiles.

Ford también tiene su pared virtual

Las aplicaciones de la pared o muro virtual llegan cada vez a más sectores. A partir de un paquete de software y hardware de la compañía especializada ICIDO, especialistas de la planta piloto de Almussafes han logrado recrear con total exactitud los vehículos que se fabrican actualmente en la factoría valenciana de Ford. Así, gracias a este muro virtual de 2 x 1.48 metros se pueden visualizar y manipular dinámicamente desde cualquier ángulo posible motores y componentes, desde la pieza más minúscula hasta la más grande.
"No habrá ni que salir a la línea de montaje para hacer pruebas o para estudiar posibles reformas en la planta", cuenta José Terrades, técnico especialista en simulaciones de la factoría Ford en Almussafes

**Publicado en "ABC"

Study shows air emissions near fracking sites may impact health


The study will be published in an upcoming edition of Science of the Total Environment.
The report, based on three years of monitoring, found a number of potentially toxic petroleum hydrocarbons in the air near the wells including benzene, ethylbenzene, toluene and xylene. Benzene has been identified by the Environmental Protection Agency as a known carcinogen. Other chemicals included heptane, octane and diethylbenzene but information on their toxicity is limited.
"Our results show that the non-cancer health impacts from air emissions due to natural gas development is greater for residents living closer to wells," the report said. "The greatest health impact corresponds to the relatively short-term, but high emission, well completion period."
That's due to exposure to trimethylbenzenes, aliaphatic hydrocarbons, and xylenes, all of which have neurological and/or respiratory effects, the study said. Those effects could include eye irritation, headaches, sore throat and difficulty breathing.
"We also calculated higher cancer risks for residents living nearer to the wells as compared to those residing further [away]," the report said. "Benzene is the major contributor to lifetime excess cancer risk from both scenarios."
The report, which looked at those living about a half-mile from the wells, comes in response to the rapid expansion of natural gas development in rural Garfield County, in western Colorado.
Typically, wells are developed in stages that include drilling followed by hydraulic fracturing, the high powered injection of water and chemicals into the drilled area to release the gas. After that, there is flowback or the return of fracking and geologic fluids, hydrocarbons and natural gas to the surface. The gas is then collected and sold.
Garfield County asked the Colorado School of Public Health to assess the potential health impacts of these wells on the community of Battlement Mesa with a population of about 5,000.
McKenzie analyzed ambient air sample data collected from monitoring stations by the Garfield County Department of Public Health and Olsson Associates Inc. She used standard EPA methodology to estimate non-cancer health impacts and excess lifetime cancer risks for hydrocarbon exposure.
McKenzie noted that EPA standards are designed to be public health proactive and may overestimate risks.
"However, there wasn't data available on all the chemicals emitted during the well development process," she said. "If there had been, then it is entirely possible the risks would have been underestimated."
The report concludes that health risks are greater for people living closest to wells and urges a reduction in those air emissions.
McKenzie said future studies are warranted and should include collection of area, residential and personal exposure data where wells are operating. Additional studies, she said, should also examine the toxicity of other hydrocarbons associated with natural gas development.
The study is entitled "Human Health Risk Assessment of Air Emissions from Development of Unconventional Natural Gas Resources." It was accepted for publication on 2/11/2012 by Elsevier Science Ireland Ltd.

**Source: University of Colorado Denver

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