Por primera vez, científicos han conseguido reproducir monos de células procedentes de embriones separados.
Los animales nacieron después de que investigadores combinaran células de diferentes embriones y los implantaran en monos hembra.
Este tipo de animales, que contienen grupos de células genéticamente distintas de más de un solo organismo, son llamados “quimeras”.
Un grupo estadounidense, que publicó su trabajo en la revista especializada Cell, dijo que el avance podría tener un impacto “enorme” para la investigación médica.
Los quimeras son importantes para estudiar el desarrollo embrionario, pero los estudios han estado durante largo tiempo restringidos a ratones.
Los monos rhesus, que son normales y están sanos, son la combinación de una mezcla de células procedentes de hasta seis individuos.
“Las células nunca se funden, pero se mantienen juntas y trabajan juntas para formar tejidos y órganos”, dijo el co-autor del estudio Shoukhrat Mitalipov, de la Universidad de Salud y Ciencia de Oregon en Portland, Estados Unidos.
Decisiones tempranas
Esfuerzos iniciales del equipo del doctor Mitalipov para producir monos quimeras vivos introduciendo células madre embrionarias de cultivo en embriones de primates –una forma estandarizada de producir ratones quimera– fallaron.
Las células madre son las células “maestras” capaces de transformarse en otras variedades más especializadas necesarias para el cuerpo.
Las células madre embrionarias que el equipo intentó usar y que no funcionaron estaban en un estado de desarrollo conocido como “pluripotencia”. Esto significa que pueden transformarse en cualquier tipo de tejido del cuerpo, pero no pueden formar una placenta o un animal entero.
Los investigadores pudieron formar monos quimeras solo cuando mezclaron células en un estado embrionario temprano, en el cual cada célula es “totipotente”.
Cortesia de BBC
A can called Newt Gingrich
Westside Gazette February 9, 2012 | Gordon, Natasha Dowdy Part III Newt Gingrich has had a rough couple of weeks. He began to lose support following a stump speech that revealed that if he were elected President of the United States, he had plans to colonize the moon by his second term.
Folks who may have considered Gingrich to be a viable candidate, and the number one Mitt Romney alternative, began to question not only Gingrich’s ability to take down President Obama, but also his level of sanity.
In addition to being the number one target of Mitt Romney, Gingrich has become a laugh line for political pundits and comedy shows as well, and if all of that wasn’t enough, the former Speaker got shellacked in the state of Florida, losing to his number one nemesis Mitt Romney by 14 percentage points. newtgingrichbio.com newt gingrich bio
By all accounts, any normal human being would be both emotionally spent and exhausted, but of course we are not talking about a normal human being, we are talking about Newt Gingrich.
Gingrich has a drive that can’t be matched by any other, and he kicks it into overdrive when he has a little motivation. At this point in time, Gingrich clearly has motivation, and that motivation is his vendetta against Mitt Romney.
Romney has over the last month or so come out against Gingrich with some of the dirtiest political ploys this country has seen in a while, and he had at one point, literally killed Gingrich, but there are a few lessons to be learned about Newt Gingrich.
He is old, he is mean, and he is not someone that you ever want to make angry, he carries a hefty bag of dirty tricks, and if you get on his bad side, he will somehow, someday get you.
At this point, no one actually believes that Gingrich has a feasible chance of becoming the President of the United States and the motives behind his campaign continue to be questioned.
The true motive behind why Gingrich is continuing to move forward with his campaign may never be revealed, but there are those who know him best believe that Newt Gingrich is playing out a personal agenda. “Newt Gingrich is playing out a personal agenda in a public forum, and it threatens the safety, health, and security of our most vulnerable people,” Mary Kahn said in Vanity Fair interview.
Kahn was the wife of Gingrich’s former campaign manager, and she also covered him as a reporter in the 1970’s. Gingrich himself has said that he found a way to immerse his insecurities in a cause large enough to justify whatever he wanted to do.
Gingrich’s life plays out like a well written script, and in terms of Gingrich’s justification regarding the things that he has done.
Newt’s relationship with his stepfather was always strained at best, and father dearest ruled his home like a dictatorship. In order to claim his independence, Gingrich pulled a play right out of a playbook that women have used since the beginning of time.
Newt began relentlessly pursuing his high school geometry teacher at the age of 19. Jackie Battley was seven years older than Gingrich at the time.
Kit Gingrich, when asked about her sons marriage to Battley stated, “He was her little boy.” Two children were born to the union of Battley and Gingrich, and the family lived on very little.
The marriage did however; provide Gingrich with an out in regards to being sent to Vietnam, as he avoided the war with both a student and a marriage deferment.
During this time, Gingrich resisted seeking gainful employment, as Newt wanted to devote all of his time to his studies.
Gingrich’s former District administrator recalled in a Vanity Fair interview that Jackie put Gingrich all the way through school. “All the way through his Ph.D….He didn’t work.” Delores Adamson stated. go to web site newt gingrich bio
This would appear to be a sharp contrast to the politician that boasts on national television that Barack Obama is the Food Stamp President, and that minorities should demand paychecks, instead of welfare checks.
In his quest to stay relevant, and secure his spot in the history of the United States, Gingrich will stop at nothing. He will say, and he will do anything. When Newt Gingrich decides to draw first blood, he is not coming to get a few drops; he is coming for the whole shebang.
All or nothing is the way that Gingrich has and will always play the game. Romney and his staff may continue to taunt Gingrich with the line “If you can’t stand the heat, then you need to get out of the kitchen, but Gingrich is still as worldly, wise, diabolical, and wild as he has ever been, and Romney would benefit himself greatly if he recognized that.
Gordon, Natasha Dowdy
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Por primera vez, científicos han conseguido reproducir monos de células procedentes de embriones separados.
