Sunday 8 May 2016

#152 Cascara de banano y el cancer de piel (Español)

Cascara de banano y el cancer de piel


Tal vez te parezca extraño, pero la cáscara de la banana tiene que ver con tu piel mucho más de lo que probablemente te imaginas.

Tanto es así que incluso podría jugar un papel fundamental en la detección temprana del cáncer de piel, la forma más común de la enfermedad, según los datos de la Sociedad Americana contra El Cáncer

Los científicos dicen que las manchas negras que se forman en la piel de las bananas maduras tienen una enzima que también desarrollan quienes sufren cáncer de piel, lo cual podría favorecer a un diagnóstico sencillo y rápido de este tipo de enfermedad.

Y no sólo se lograría detectar antes la enfermedad, sino también aumentar las posibilidades de supervivencia.

¿Cómo es esto posible?

Una extraña coincidencia entre la piel de los humanos y la cáscara de la banana que podría ser la clave para diagnosticar cáncer de piel.

Cuando las bananas maduran, su piel queda cubierta de pequeñas manchas oscuras causadas por una enzima llamada tirosinasa.

La aparición de las manchas tiene lugar por el mal funcionamiento de la enzima y, en el caso de la piel humana, ésta puede alterar la pigmentación, que protege a nuestro cuerpo de irritantes (inflamaciones) y toxinas.

Y si esta misma enzima se presenta en la piel humana en grandes cantidades, provoca el desarrollo de melanoma, el tipo de cáncer de piel más peligroso.

Los científicos observaron la similitud entre la piel humana y la de la banana, y crearon una herramienta de diagnóstico. A través de un escáner estudiaron las manchas de las cáscaras de banana, que son, aproximadamente, del mismo tamaño que los melanomas de la piel humana.

Tras probarlo en la banana, aplicaron el escáner en tejidos de piel humana.

Y las conclusiones de los investigadores de la EPFL fueron que la enzima de la banana es un indicador fiable del crecimiento del melanoma. Trabajando con la fruta se desarrolló y probo un método de diagnóstico antes de aplicarlo en muestras humanas con el que se pudo detectar la presencia y la cantidad de estas enzimas.

El escáner tiene ocho electrodos diminutos, espaciados entre sí como si púas de dientes que "peinan" la piel para medir la cantidad y distribución de tirosinasas.

De acuerdo con el estudio, en la etapa más temprana (etapa 1) del cáncer de piel, la enzima apenas está presente y se distribuye de manera más uniforme en la etapa 2, para hacerlo de forma desigual en la etapa 3, cuando el cáncer ya comenzó a extenderse a otras partes del cuerpo.

Con esta herramienta se puede detectar las fases 2 y 3 de melanoma y utilizarlo para diagnosticar la fase 4.

AAM

#151 The Fundamental Stage of Human Development: Embryo Implantation (English)

The Fundamental Stage of Human Development: Embryo Implantation
[Science Daily: New method allows first look at key stage of human development, embryo implantation]

Embryo implantation indicates the arrival of the of the blastocyst on the functional layer of endometrium after 5 days after ovulation or fertilization as the result of the coordination between ovulation and endometrial development.
A human embryo 12 days after fertilization in vitro
Copyright. The Rockefeller University
Despite significant development in the biomedical field, the mechanism of the molecular and cellular processes in human development that occurs 14 days after fertilization was a conundrum. In fact, Ali Brivanlou, head of the Laboratory of Stem Cell Biology, coined the blastocyst as "a complete black box". However, the scientists in the Rockfeller University successfully realized the process of implantation in the laboratory from creating the optimum chemical environment for the blastocysts, which provided the appropriate scaffolding for the implementation to occur. As a result, scientists were to attain the opportunity to solve such riddles like early pregnancy loss, which is like "sheding light inside that box".

The implantation process that occurred outside the human uterus demonstrated things beyond what scientists expected. In fact, this process confirmed the variations between species owing to the different development compared to the model system that was based on mouse embryology. Also, the scientists observed the staggering phenomenon called self-organization. For instance, the water molecules would form a symmetrical shape without any external force, which is definitely going against the nature of increasing antropy. Although self-organization do occur in human embryonic stem cells, it is to be discovered in virtue of this experiment that self-organization appear in the context of a whole human embryo. Thus, human embryo can develop in the complete absence of maternal input for the first 12 days, and this observation controverts to the preexisting theory that implantation is triggered by molecular crosstalk.

It is a promising experiment as it complied with the international bioethical guidelines. In fact, this experiment provided the scaffolding for the reexamination of the 14-day limitation rule to be varied based on the different types of embryo research and their pros and cons. Moreover, the Rockefeller research team laid emphasis on the importance to educate the public and abide by the ethical consensus when proceeding this research. The successful materialization of the human embryo implantation process in an experimental setting is evidently going to act as a catalyst in grasping the causes of the disorders such as early pregnancy losses and birth defects.

New method allows first look at key stage of human development, embryo implantation. Science daily. Rockfeller University. 4 May, 2016. Web. 8 May, 2016
<https://www.sciencedaily.com/releases/2016/05/160504141444.htm>
Mescher, AL. Junqueira's Basic Histology: Text and Atlas, 12th Edition. The McGraw-Hill Companies, Inc. Web. 8 May, 2016 <https://www.accessmedicine.com>

KSJ

Sunday 1 May 2016

#150 The Spleen (English)

The Spleen


The spleen is one of the largest organs in the lymphatic system. It is a brown, flat and oval shaped organ that filters and stores blood to protect the body from infections and blood loss.

Location

The spleen is located between the stomach and the diaphragm in the left hypochondriac region of the abdominal body cavity, protected by the ribs. It is delivered oxygenated blood by the splenic artery, which branches off from the aorta and the celiac trunk. The splenic vein carries deoxygenated blood away.

Structure

The spongy inner tissue of the spleen contains blood vessels and hollow sinuses to store blood, which it can release into circulation when the body has been injured and additional blood is needed. Platelets are also stored with the blood to help form blood clots if needed and to prevent further blood loss.

Functions

Around the vessels and sinuses are regions of red pulp and white pulp. The red pulp regions contain reticular fibers that filter old blood cells from the blood flowing through the spleen. The captured cells are digested and leftover iron and hemoglobin are recycled. The zone between the red and white pulp acts as a filter to capture pathogens in the blood and pass them on to the white pulp. The white pulp, made of lymphatic tissue containing macrophages, T lymphocytes, and B lymphocytes destroys pathogens in the blood and produce antibodies. During certain infections the spleen may enlarge due to the increase in stored white blood cells, captured pathogens and antibodies.

Importance

The spleen is not a vital organ, meaning that its functions are useful, but not essential for life. In its absence, red bone marrow, the liver and the lymph nodes can do the same filtration and blood recycling functions of the spleen. Because it is not one of the vital organs it is soft, spongy and vascular. This means that any damaged caused to the spleen is usually treated by it’s entire removal. Untreated damage to the spleen could result in internal hemorrhaging and eventual death.

SJS