lunes, 12 de septiembre de 2011

¿Se pueden hacer calculadoras con microorganismos?


¿Se pueden hacer calculadoras con microorganismos?
En un número reciente de la revista Natural Computing, investigadores de la Universidad Politécnica (UPM) y la Universidad Autónoma de Madrid (UAM) proponen una alternativa para resolver problemas matemáticos complejos en un simple tubo de ensayo.
FUENTE | UAM - mi+d12/09/2011
Desde que surgieron hace 4.000 de millones de años, los seres vivos han desarrollado la capacidad de adaptarse a su entorno. Son capaces de percibir lo que les rodea, comunicarse con otros organismos y modificar su entorno según sus necesidades. Un ejemplo de esto lo podemos encontrar en determinadas bacterias que pueden formar macroestructuras conocidas como biopelículas. 

En dichas estructuras existe un alto grado de organización y comunicación que permiten la supervivencia de la comunidad. Pero, ¿cómo unos organismos en teoría tan “simples” son capaces de producir sistemas tan complejos? Y lo que es más importante, ¿podemos aprovechar esos sistemas para nuestro beneficio? 

Los últimos avances que se están realizando en el campo de la secuenciación de genomas y en la actividad de los genes en general, están ampliando nuestros conocimientos de los distintos modos en los que funcionan los mecanismos de percepción de los microorganismos y a su vez los mecanismos de interacción entre ellos. Dichos conocimientos han dado lugar a la aparición de una disciplina denominada Biología de Sistemas, que se encarga de recopilar esos datos y correlacionarlos con lo que se observa en la naturaleza. 

De hecho, aprovechando ese conocimiento se han modificado genéticamente ciertas bacterias con el fin de que proporcionen una señal medible ante un estímulo dado. No obstante, la utilización de una única estirpe bacteriana conlleva una serie de problemas, por ejemplo: la disminución de la viabilidad de la bacteria o la fiabilidad de la respuesta, según lo complejo del diseño experimental. 

El Grupo de Computación Natural de la Universidad Politécnica de Madrid junto con el grupo Rizosfera-UAM, en un artículo publicado recientemente en la revista Natural Computing, han propuesto una alternativa para que se puedan resolver problemas matemáticos complejos en un simple tubo de ensayo. 

Dicha alternativa consistiría en dividir las tareas entre varias estirpes de bacterias, en vez de utilizar una única estirpe bacteriana modificada. Partiendo de esta premisa, los investigadores proponen diseñar bacterias “a la carta” mediante modificación genética, que respondan de una manera determinada y con una intensidad dada ante una señal química presente en el ambiente. 

De tal modo, los investigadores podrían tener a su disposición un arsenal de bacterias que posiblemente puedan mezclarse en un tubo de ensayo como si fueran las líneas de un código de un programa, en donde pudieran recibir las señales externas y a su vez comunicarse entre ellas para obtener una respuesta adecuada. Así, y a modo de ejemplo, han mostrado cómo se deberían modificar tres bacterias para resolver un problema lógico simple, a saber, determinar si en un medio dado aparece uno y sólo uno de dos compuestos químicos determinados produciendo o no una proteína fluorescente como respuesta. 

Dada la versatilidad de este sistema, las aplicaciones a desarrollar pueden ser múltiples. Por ejemplo, se podrían construir dispositivos de tamaño reducido y con un bajo impacto ambiental capaces de determinar qué contaminantes y en qué cantidad hay en un embalse con destino al consumo humano. Además, dada la gran cantidad de bacterias que pueden crecer en un volumen mínimo, los investigadores consideran que se encuentra ante la posibilidad de construir microcircuitos que podrían permitir resolver problemas matemáticos complejos. 
una alternativa para resolver problemas matemáticos complejos en un simple tubo de ensayo


Referencia bibliográfica
Goñi-Moreno A, Redondo-Nieto M, Arroyo F, Castellanos J., Biocircuit design through engineering bacterial logic gates, en: “Natural Computing”, 10(1): 119-127, DOI: 10.1007/s11047-010-9184-2 (2011).
 

domingo, 11 de septiembre de 2011

Terrorismo


 

We join you in remembering those whose lives were taken.
As we take time to reflect on the 10th Anniversary of a day none of us will ever forget, let us come together to grieve, to remember, to express our gratitude to those who demonstrated what it is to be a hero, and to pledge ourselves to live in honor of their bravery.
El mundo actual dista mucho del mundo de nuestra infancia. Los eventos con víctimas masivas debidos a demoledoras catástrofes naturales, creadas o inducidas por el hombre nos han cambiado para siempre, y como médicos debemos estar preparados para actuar con nuestro saber y experiencia. ¿Sabremos que hacer ante un tsunami, un temblor, un incendio, un apagón, una inundación, actos de terrorismo o una guerra con armas nucleares?
En este día especial le enviamos de nuevo algunos articulos con estos temas, conocimiento que esperemos nunca necesitar, pero es mejor tener este tipo de información que pudiera sernos util en su momento dado.

Preparación para emergencias para incidentes biológicos y químicos: un estudio de los programas de residencia en anestesiología de los Estados Unidos 
Emergency preparedness for biological and chemical incidents: a survey of anesthesiology residency programs in the United States.

Candiotti KA, Kamat A, Barach P, Nhuch F, Lubarsky D, Birnbach DJ.
Department of Anesthesiology, Perioperative Medicine and Pain Management, University of Miami School of Medicine/Jackson Memorial Hospital, R-C370, 1611 NW 12th Ave., Miami, Florida 33101, USA.kcandiotti@miami.edu
Anesth Analg. 2005 Oct;101(4):1135-40
Abstract 
We surveyed health care professionals about their preparations to manage the clinical problems associated with patients exposed to hazardous substances, including weapons of mass destruction (WMD). Training for WMD is considered a key part of public health policy and preparedness. Although such events are rare, when they do occur, they can cause mass casualties. In many models of mass casualty management, anesthesiology personnel are responsible for treating patients immediately on arrival at the hospital. We studied the extent of training offered to anesthesiology personnel in the use of WMD protective gear and patient management inUnited States (US) anesthesiology residency programs. Information was obtained via an online survey to all program directors and chair persons of anesthesiology programs. We polled all of the 135 US anesthesiology programs of which 90 (67%) responded. Only 37% had any form of training, and many of them did not repeat training after initial sessions. Twenty-eight percent of programs east of the Mississippi River reported some form of training whereas only 17% of programs west of it reported training available. The majority of anesthesia residency programs in the US that responded to our survey provided little or no training in the management of patients exposed to WMD. IMPLICATIONS: In an attack involving weapons of mass destruction or toxic chemicals, anesthesiologists will provide care. Our survey of United States anesthesiology residency programs demonstrated that there is limited training of residents regarding the anesthetic management of patients injured by weapons of mass destruction. This has serious public health implications.
Manejo de la vía aérea durante un evento con víctimas en masa
Airway management during a mass casualty event.
Talmor D.
Source
Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center, One Deaconess Road, Boston, MA 02215, USA. dtalmor@bidmc.harvard.edu
Respir Care. 2008 Feb;53(2):226-31
Abstract
Mass casualty respiratory failure will lead to many challenges, not the least of which is safe and secure management of the victims' airways. These patients will be sicker than those typically managed in the operating room and will require more emergency management of their airways. Mass casualty incidents involving biological or chemical agents will pose the additional risk of exposure to pathogen. During the severe acute respiratory syndrome epidemic in Toronto, airway manipulation was clearly identified as the procedure most associated with risk to health care workers. Planning for scenarios such as these will require consideration of personal protection for health care workers to minimize these risks. Understanding the risks involved and the airway techniques required for each possible scenario will be key to planning and preparation
http://www.rcjournal.com/contents/02.08/02.08.0226.pdf
 

Mesa redonda sobre detección de bioterrorismo: información basada en sistema de vigilancia
Roundtable on bioterrorism detection: information system-based surveillance.
Lober WB, Karras BT, Wagner MM, Overhage JM, Davidson AJ, Fraser H, Trigg LJ, Mandl KD, Espino JU, Tsui FC.
University of Washington, Seattle, Washington, USA.
J Am Med Inform Assoc. 2002 Mar-Apr;9(2):105-15.
Abstract
During the 2001 AMIA Annual Symposium, the Anesthesia, Critical Care, and Emergency Medicine Working Group hosted the Roundtable on Bioterrorism Detection. Sixty-four people attended the roundtable discussion, during which several researchers discussed public health surveillance systems designed to enhance early detection of bioterrorism events. These systems make secondary use of existing clinical, laboratory,paramedical, and pharmacy data or facilitate electronic case reporting by clinicians. This paper combines case reports of six existing systems with discussion of some common techniques and approaches. The purpose of the roundtable discussion was to foster communication among researchers and promote progress by 1) sharing information about systems, including origins, current capabilities, stages of deployment, and architectures; 2) sharing lessons learned during the development and implementation of systems; and 3) exploring cooperation projects, including the sharing of software and data. A mailing list server for these ongoing efforts may be found at http://bt.cirg.washington.edu


MANUAL DE INTERVENCIÓN PSICOLÓGICA Y SOCIAL EN VICTIMAS DE TERRORISMO 11-M
 Ana Zapardiel Fernández, Syra Balanzat Alonso

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