Viaje a las profundidades del Océano (VIDEO) + Extrañas criaturas marinas (FOTOS)

Imagen
  Pero, ¿qué es un Océano? U n océano es una enorme masa de agua salada que representa un importante ecosistema para el equilibrio ecológico de la Tierra y que constituye el  71% de la superficie terrestre , gracias a los 360,132,000 km² de su extensión. Y,  ¿cuántos océanos existen? Lo que cubre gran parte de la superficie de la Tierra, es en sí, un solo océano. Es decir, una sola masa de agua. Para un mejor estudio, el hombre dividió esta enorme masa en 5 partes de acuerdo a su ubicación geográfica. Por ello, la expresión “los océanos”, es correcta. Importancia de los océanos *Absorben entre un 25 y 30% del dióxido de carbono emitido a la atmósfera, por lo que Equilibran el clima de toda la Tierra. *Representan numerosos ecosistemas para diversas formas de vida animal, vegetal, bacteriana, protista y fúngica. *Son hogar para miles de especies, conocidas y aún desconocidas. Existen aproximadamente 250,000 especies conocidas, pero se cree que puedan haber 750,000 más. *Proveen fuentes

One Drug to Shrink All Tumors

A single drug can shrink or cure human breast, ovary, colon, bladder, brain, liver, and prostate tumors that have been transplanted into mice, researchers have found.

The treatment, an antibody that blocks a "do not eat" signal normally displayed on tumor cells, coaxes the immune system to destroy the cancer cells.

Biologist Irving Weissman and colleagues of the Stanford University School of Medicine in Palo Alto, California, showed that blocking CD47 (a protein which block the inmune system) with an antibody cured some cases of lymphomas and leukemias in mice by stimulating the immune system to recognize the cancer cells as invaders. Moreover, he and colleagues have shown that the CD47-blocking antibody may have a far wider impact than just blood cancers.

"What we've shown is that CD47 isn't just important on leukemias and lymphomas," says Weissman. "It's on every single human primary tumor that we tested." Moreover, Weissman's lab found that cancer cells always had higher levels of CD47 than did healthy cells. How much CD47 a tumor made could predict the survival odds of a patient.

"We showed that even after the tumor has taken hold, the antibody can either cure the tumor or slow its growth and prevent metastasis," says Weissman.

Cancer researcher Tyler Jacks of the Massachusetts Institute of Technology in Cambridge says that although the new study is promising, more research is needed to see whether the results hold true in humans. "The microenvironment of a real tumor is quite a bit more complicated than the microenvironment of a transplanted tumor," he notes, "and it's possible that a real tumor has additional immune suppressing effects."

Weissman's team has received a $20 million grant from the California Institute for Regenerative Medicine to move the findings from mouse studies to human safety tests. "We have enough data already," says Weissman, "that I can say I'm confident that this will move to phase I human trials."
Source: Science

Comentarios

Entradas populares de este blog

Experimentación con animales: Ventajas y desventajas

Ataques de Lobos a personas en España y resumen de ataques en el Mundo: casos reales y motivaciones

AVES DEL CERRITO DE SAN CRISTOBAL (CHIAPAS, MÉXICO)