Blog of Applied Research

Clinical research on newborns urine by NMR at Bruker Biospin
NMR spectra of urine samples taken from newborns will allow to elaborate statistic methods for the diagnosis of a number of diseases More at Bruker-Biospin

 

Molecular Engineering of Organic Sensitizers for Solar Cell Applications
Sanghoon Kim, Jae Kwan Lee, Sang Ook Kang, Jaejung Ko, J.-H. Yum, Simona Fantacci, Filippo De Angelis, D. Di Censo, Md. K. Nazeeruddin, and Michael Grätzel
J. Am. Chem. Soc.; 2006; ASAP Web Release Date: 05-Dec-2006; (Article) DOI:
10.1021/ja066376f

 

Photosensitized Reduction of Water to Hydrogen Using Human Serum Albumin Complexed with Zinc-Protoporphyrin IX
Teruyuki Komatsu, Rong-Min Wang, Patricia A. Zunszain, Stephen Curry, and Eishun Tsuchida
http://dx.doi.org/10.1021/ja0656806

 

Tumour Metabolomics in Animal Models of Human Cancer
Julian L. Griffin and Risto A. Kauppinen
http://dx.doi.org/10.1021/pr060464h

 

Engineering Light-Gated Ion Channels
Matthew R. Banghart, Matthew Volgraf, and Dirk Trauner
http://dx.doi.org/10.1021/bi0618058

 

X-ray Structure of a Hydroxylase-Regulatory Protein Complex from a Hydrocarbon-Oxidizing Multicomponent Monooxygenase, Pseudomonas sp. OX1 Phenol Hydroxylase,
Matthew H. Sazinsky, Pete W. Dunten, Michael S. McCormick, Alberto DiDonato, and Stephen J. Lippard
http://dx.doi.org/10.1021/bi0618969

 

La yerba mate, herramienta médica

BBC Mundo Ciencia

Nota de BBCMundo.com:

http://news.bbc.co.uk/go/pr/fr/-/hi/spanish/science/newsid_6206000/6206128.stm

Publicada: 2006/12/04 17:45:23 GMT

 

 

Análisis de sangre en un chip / Portable 'lab on a chip'

Somerterse a un análisis de sangre sopone ciertas molestias: pedir cita en el laboratorio, el ayuno previo, el pinchazo, esperar los resultados... Inconvenientes que desaparecerían si la tecnología presentada hoy por el MIT llega a producirse y usarse de forma masiva. Sus investigadores lo definen como el 'laboratorio en un chip', un éxito de la miniaturización que permitiría examinar la calidad de la sangre desde un dispositivo de una píldora. Ésta está siendo desarrollada con fines militares, para que los soldados puedan conocer al momento si han sido víctimas de un ataque químico o bioológico que afecta a su organismo, pero el centro de investigación ya aventura que podría servir para

realizar análisis de sangre instantáneos o para alertar a los enfermos cardiacos si sufren alguna anomalía. ¿Nanotecnología? Posiblemente, el MIT habla de hacer correr la sangre por canales de 10 micras de diámetro.

 

Portable 'lab on a chip' could speed blood tests. MIT micropump assures portability, efficiency, in routine or combat conditions

 

Anne Trafton, News Office

October 16, 2006

 

Testing soldiers to see if they have been exposed to

biological or chemical weapons could soon be much

faster and easier, thanks to MIT researchers who are

helping to develop a tiny diagnostic device that could

be carried into battle.

 

By tweaking the design of a tiny pump, researchers

affiliated with MIT's Institute for Soldier

Nanotechnologies have taken a major step towards

making an existing miniature "lab on a chip" fully

portable, so the tiny device can perform hundreds of

chemical experiments in any setting.

 

"In the same way that miniaturization led to a

revolution in computing, the idea is that miniature

laboratories of fluid being pumped from one channel

to another, with reactions going on here and there,

can revolutionize biology and chemistry," says Martin

Bazant, associate professor of applied mathematics

and leader of the research team.

 

Within the lab on a chip, biological fluids such as

blood are pumped through channels about 10

microns, or millionths of a meter, wide. (A red blood

cell is about 8 microns in diameter.) Each channel

has its own pumps, which direct the fluids to certain

areas of the chip so they can be tested for the

presence of specific molecules.

 

Until now, scientists have been limited to two

approaches to designing labs on a chip, neither of

which offer portability. The first is to mechanically

force fluid through microchannels, but this requires

bulky external plumbing and scales poorly with

miniaturization.

 

The second approach is capillary electro-osmosis,

where flow is driven by an electric field across the

chip. Current electro-osmotic pumps require more

than 100 volts of electricity, but the MIT researchers

have now developed a micropump which requires

only battery power (a few volts) to achieve similar

flow speeds and also provides a greater degree of

flow control.

 

The key to boosting energy efficiency is altering the

electric field in the channel, Bazant said. Instead of

placing electrodes at each end of the channel, as in

capillary electro-osmosis, the voltage can be lowered

substantially with alternating current (AC) applied at

closely spaced microelectrode arrays on the channel

floor. Existing AC electro-osmotic pumps, however,

are too slow for many applications, with velocities

below 100 microns per second.

 

In the new system, known as a three-dimensional AC

electro-osmotic pump, tiny electrodes with raised

steps generate opposing slip velocities at different

heights, which combine to push the fluid in one

direction, like a conveyor belt. Simulations predict a

dramatic improvement in flow rate, by almost a factor

of twenty, so that fast (mm/sec) flows, comparable to

pressure-driven systems, can be attained with

battery voltages. Experiments in the lab of Todd

Thorsen, assistant professor of mechanical

engineering, have recently demonstrated the

effectiveness of the design.

 

"It's just a huge improvement with a very simple

idea," said Bazant.

 

Thorsen's group is working toward integrating the

pumps into a portable blood analysis device, which

soldiers could carry onto the battlefield. If exposure

to chemical or biological weapons were suspected,

the device could automatically and rapidly test a

miniscule blood sample, rather than sending a large

sample to a lab and waiting for the results. The chips

are so small and cheap to make that they could be

designed to be disposable, Bazant said, or they

could be made implantable.

 

Potential applications are not limited to military use --

imagine going to a doctor's office and getting test

results immediately. The technology could also be

useful for first responders. If emergency personnel

knew immediately whether a person had suffered a

heart attack or a stroke, they could start the

appropriate treatment right away.

 

Labs on a chip can also be used in traditional

chemistry or biology labs to speed up processes

such as DNA testing or screening for the presence of

certain antigens. Only tiny amounts of reactants

would be needed, and experiments could be done

more rapidly and efficiently.

 

"Instead of a thousand people pouring test tube A

into test tube B in different laboratories, you've got a

tiny little chip with thousands of experiments all going

on at once," Bazant said.

 

Bazant and former MIT postdoctoral associate

Yuxing Ben published an article on the theoretical

work in the online edition of the journal Lab on a

Chip, and a related experimental paper will appear in

an upcoming edition of Applied Physics Letters. Co-

authors on that paper with Bazant and Thorsen are

graduate student J.P. Urbanski and postdoctoral

associate Jeremy Levitan.

 

The research was funded by the U.S. Army through

the Institute for Soldier Nanotechnologies.

 

DNA Computer Plays Complete Game of Tic-Tac-Toe

October 18, 2006

 

http://www.sciam.com/print_version.cfm?articleID=000A70B0-8024-1536-802483414B7F011B

 

Breast Cancer Risk Linked To Red Meat, Study Finds

 

http://www.washingtonpost.com/wp-dyn/content/article/2006/11/13/AR2006111300824_pf.html

 

 

The Calculating Brain: New Studies Suggest That Neurons Are Built To Perform Simple Arithmetic

 

http://www.hhmi.org//news/yuste20061120.html

 

 

Genetic risk for violent behavior?

By JACOB RUSSELL

 

WASHINGTON, Nov. 27 (UPI) -- British Prime

Minister Tony Blair might be on to something in his

recent call to clamp down early on antisocial

behavior, a recent study shows.

 

"If we are not prepared to predict and intervene far

more early, then there are children that are going to

grow up in families that we know perfectly well are

completely dysfunctional," Blair said. "And the kids a

few years down the line are going to be a menace to

society and actually a threat to themselves.

 

Dr. Essi Viding, professor in the Department of

Psychology at the University of London, and Uta

Frith, professor at the Institute of Cognitive

Neuroscience and the Department of Psychology at

University College London, collaborated on recent

research on genes for susceptibility to violence.

 

The study shows that low activity in the MAOA gene,

which produces the enzyme monoamine oxidase-A,

is linked to aggressive behavior in men. MAOA-L, the

term used to describe low-activity carriers, may

contain a vulnerable neural signature that could turn

violent in a bad environment, particularly in the

amygdala. The amygdala is located between the

right and left cerebral hemispheres and controls the

emotions. Patients with MAOA-L appear to have a

shorter amygdala stem than others.

 

The research indicates that if carriers of the MAOA-L

gene grow up in high-risk families, they will be more

susceptible to violent behavior.

 

Though no one appears to know exactly what Blair is

up to, the assumption is that he recognizes that

personality disorders do not come as a surprise

when an individual turns 18. He is aware of the

importance of early environmental problems,

particularly for those who come from families that

have concentrated psychiatric vulnerability.

 

Viding supports this.

 

"The discovery that psychopathic tendencies are

strongly heritable suggests that we need to get help

for these youngsters early on," she said.

 

She suggests it would be important to provide

support structures and programs that take place

during the important phase of early brain

development.

 

"Animal studies suggest that if (social circumstances)

are changed early enough, this is effective," she told

United Press International. "Early enough being the

key. Given what we know about different brain

profiles of different subtypes of antisocial behavior,

we may also need to think about tailoring the

treatment. For example, we should take different

approaches depending on a risk genotype. ... I

believe that MAOA-L is only part of the bigger

picture."

 

While the MAOA-L gene can be a predictor, it is

important to recognize that the genes influencing

behavior have a very small effect. Even combined

with stressful environments, there is no perfect

indication that one will become antisocial.

 

This issue is not fundamentally genetic, said Dr.

Sujatha Byravan, president of the Council for

Responsible Genetics. He said Blair's claims

targeted children raised by single mothers who

become a menace to society. Blair was suggesting

identifying the kinds of situations that put children at

risk and addressing the problem before birth.

 

"We don't have a genetic reason for criminal

behavior," she said. "But it's interesting that genetics

as the reason for criminal behavior continues to

appear."

 

"Gene therapy has not worked," she said. "Maybe

you can repair (the problem) by changing the social

circumstances in a person's life or doing other things,

but you can't change it just by changing someone's

genes."

 

Viding agrees. "Fixing the genes is totally unrealistic

and I doubt Mr. Blair would propose that. The effect

of any one gene on behavior is so minute, and it

does not spell destiny. We are not talking about

dominant genes for eye color here. You need

accumulative genetic risk."

 

Copyright 2006 by United Press International. All

Rights Reserved.

 

 

Night of the living enzyme

http://www.eurekalert.org/pub_releases/2006-11/dnnl-not112806.php

1