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UN INTERESANTE ARTUCULO DEL WASHINGTON POST.

Human Brain Cells Are Grown In Mice

By Rick Weiss

By injecting human embryonic stem cells into the brains of fetal mice inside the womb, scientists in California have created living mice with working human brain cells inside their skulls.

The research offers the first proof that human embryonic stem cells -- vaunted for their potential to turn into every kind of human cell, at least in laboratory dishes -- can become functional human brain cells inside a living animal, reaching out to make connections with surrounding brain cells.

The human cells had no apparent impact on the animals' behavior. About 100,000 cells were injected into each animal and just a fraction survived in their new hosts. That means the animals' brains were still more than 99 percent mouse -- a precaution that helped avoid ethical objections to creating animals that were "too human."

The finding that the human cells are working in their new environment provides encouragement for those who hope to develop stem-cell-based therapies for neurodegenerative diseases such as Parkinson's.

More immediately, mice with humanized brains could be a boon for research, providing a living laboratory where scientists can study human brain diseases and drug companies can test the safety of experimental medicines.

"Let's say you're in the last stages of research before testing a new drug in humans," said lead researcher Fred Gage of the Salk Institute for Biological Sciences in La Jolla, Calif. "This could help tell you what effect it will have on human neurons inside a brain."

The work, published in today's issue of the Proceedings of the National Academy of Sciences, is the latest in the ethically challenging field of human-animal "chimera" research -- a reference to the Chimera of Greek mythology, which had a lion's head, a goat's body and a serpent's tail.

In previous studies, scientists had injected brain cells from aborted human fetuses into the brains of rodents and shown that the human cells could survive and migrate to various brain regions. But because those human brain cells were relatively mature, they were larger than their rodent counterparts and it often was unclear whether they were working.

The new work, which started with human embryonic stem cells instead of cells that had already become brain cells, showed that those human cells developed into all the major kinds of cells normally found in mammalian brains, namely neurons and nerve-nurturing glial cells. It also showed that the neurons are biologically active and make what appear to be good connections, or synapses, with adjacent mouse cells.

"It's the best evidence yet that they are integrating and functioning," said Irving Weissman, a Stanford University stem cell scientist. "It's a nice advance."

Reflecting growing concerns about the ethics of making animal-human hybrids, the National Academy of Sciences earlier this year released voluntary guidelines on chimera research that have been adopted by major research institutes and have been made mandatory in California for state grant recipients. The rules aim to limit the extent to which animals -- especially primates -- get humanized and to prevent the creation of human embryos inside animal wombs through the mating of animals bearing human eggs or sperm.

Those rules were not yet drawn up when the Salk experiments were conducted, but the protocol had the approval of the institute's ethics board. Moreover, before the results were published, the team asked for a new review, which concluded the work would have been approved even under the new NAS guidelines, Gage said.

The guidelines allow for a slow scale-up of the proportion of human cells in animals' brains. Gage estimated that in the latest work as few as 100 of the 100,000 injected cells survived and became integrated with the mouse brains, which typically contain 75 million to 90 million mouse cells.

Henry Greely, a Stanford law professor and ethicist who has reviewed proposals to create human-mouse chimeras, said the work looked "interesting, good and ethical" by current standards.

Stem cell therapies "will only work if the transplanted cells will make those connections," Greely said, "and there's no better place to test that but in an animal model."

In painstaking surgeries conducted on a small, heated operating platform, Gage and his co-workers, including Alysson R. Muotri and Kinichi Nakashima, partially removed 14-day-old mouse fetuses from the womb, being careful not to disrupt the placenta that provides maternal nourishment. After injecting the human stem cells into curved cavities of the brain called the lateral ventricles, they tucked the pups back in for their last week of development.

The human cells, taken from days-old human embryos by a San Diego company, CyThera Inc., had been engineered to emit a green fluorescence. That helped them stand out against the mouse cells when the animals' brains were later analyzed under the microscope.

Although embryonic stem cells have sometimes turned into tumors in other experiments, no such growths developed, Gage said. Nor were they rejected by the mice's immune systems, perhaps because they were injected so early that they were perceived as "self" rather than "other."

The cells migrated into the forebrain, where they grew only to the size of mouse neurons. Most extraordinary, Gage said, was that they connected to others and were firing -- though it is still unclear if they fire in electrical patterns typical of mouse or human cells.

One possible application, Gage said, would be to place healthy human cells in the brains of mice that have versions of human neuronal diseases, such Alzheimer's, Lou Gehrig's or Parkinson's, and see how the neurons fare.

That experiment might reveal whether those diseases have their roots elsewhere and subsequently affect neurons, or whether they emerge directly from ill neurons, in which case the human cells would remain unaffected.


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NUEVOS LUJOS Y MARKETING JURIDICO

En conversacion con unos posibles clientes de marketing juridico ,´les señalaba la mportancia del marketing y le damos unos ejemplos. Han quedado sorprendidos, pero lo más interesante es que están absolutamente convencidos de que sin acciones de marketing van a desaparecer. ( MARJURIDICO.BLOGSPOT.COM)

HAY EFECTIVAMENTE NUEVOS LUJOS

Nuevos lujos: marcas caras que cuestan poco ha dicho Juanjo Rodríguez en España y que compartimos con los de Marketing Jurídico en Chile… Ciertamente que esto es también válido a los Grandes estudios de Abogados nacionales. Ustedes van a ver grandes fusiones y asociaciones con importantes estudios jurídicos Españoles que son un lujo. Porque es obvio las grandes inversiones españolas en Chile a si lo ameritan.

Una nueva clase de marcas está naciendo: aquellas que son caras, pero cuestan poco. Piensa en Starbucks o Victoria’s Secret en Estados Unidos, o Il Caffè di Roma y Actimel (Danone) en España. Estas marcas ofrecen su producto hasta un 200% más caro que sus competidores, y sin embargo tienen una clientela tremendamente fiel.

Una de las claves es que, aunque más caras que la competencia, en valor absoluto su precio no es muy alto. Por ejemplo, 2,25 euros por un Actimel (no estamos hablando de comprar un Ferrari).
¿Que es el New Luxury en Los estados Unidos?
En Estados Unidos este movimiento se ha denominado New Luxury, y su explicación es compleja: la misma persona que paga 3 dólares por un café de Starbucks, o 400 por unos zapatos de Manolo Blahnik, solo compra los cereales y la leche cuando están en promoción. Los consumidores tienen patrones de compra radicalmente distintos en función de la categoría de producto, y del valor percibido que les ofrece la marca.

¿En que se basa el valor?

Este valor se basa en tres ejes: beneficios técnicos (como se “construye” el producto), funcionales (la experiencia que ofrece) y emocionales (como hace sentir al cliente). Estos últimos son esenciales: aunque sirvan para necesidades básicas, estos productos “refuerzan las emociones del consumidor, y alimentan sus aspiraciones de una vida mejor”. Cada vez es menos importante el producto en sí, y más la historia que nos cuenta.

Esta tendencia refuerza uno de los principales mensajes del marketing de los últimos años: la existencia de dos estrategias ganadoras radicalmente opuestas:

1º Orientación a precio:

 Ser el más barato de forma sistemática
 “Siempre Precios Bajos”
 El mejor exponente, Walmart en Estados Unidos
2º Orientación a marca:

 Dotar de una fuerza a la marca que hace casi irrelevante el precio
 Fuerte diferenciación emocional
 Posicionamiento basado en atributos “soft”
 El mejor exponente, Nike
Probablemente, aunque parezca un fenómeno reciente, esta evolución se base en los mismos principios que ya definía uno de los clásicos gurús del management, Michel Porter, en sus estrategias genéricas: precio, diferenciación o enfoque.
Saludos Rodrigo González Fernández, marjuridico.blogspot.com