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dimanche 23 septembre 2012

BIOMARKERS


What are BIOMARKERS ?

 
The NIH BIOMARKERS DEFINITIONS WORKING GROUP defined a biomarker as a characteristic that is objectively measured and evaluated as indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to therapeutic interventions.

 
Biomarkers Definitions Working Group: Biomarkers and surrogate endpoints: preferred definitions and conceptual framework. Clin Pharmacol Ther 2001, 69:89-95. PubMed Abstract | Publisher Full Text OpenURL

. BIOMARKERS & PERSONNALIZED MEDICINE
 
Biomarkers can be used to follow body processes and diseases in humans and animals and are a good tool to predict how a patient will respond to a medicine or whether they have, or are likely to develop, a certain disease. Biomarkers revolution follow the needs of personnalized medicine and impact each area of the Lifeciences with applications including diagnosis, prognosis, and selection of targeted therapies.
Personalized medicine using DNA biomarkers: a review : Andreas Ziegler , Armin Koch, Katja Krockenberger and Anika Großhennig. Human Genetics. 2012. Springer Link

. EXAMPLES OF BIOMARKERS
Several Biomarkers have been identified :
  • Diagnostic biomarkers – to identify the presence of a disease. Many quick diagnostic tests exists to identify in few minutes the presence of a pathogen which is of interest for emergency medicine and allow a rapid treatment and the limitation of outbreaks with the isolation of infected people (Malaria ...).
    >> IDBD : Infectious Disease Biomarker Database :
  • Toxicity biomarkers – to serve as early sensitive indicators of treatment-induced toxicity.
    >> BIOMARKERS OF TOXICITY
  • Biomarkers of risk – which may identify subpopulations that respond to a treatment in different ways. For example, they may correlate with an increased risk of drug toxicity, or a risk of reduced drug efficacy. Such biomarkers serve as a cornerstone in personalizing medicine, enabling practitioners to select the most appropriate treatment for individual patients.
    >> BIOMARKERS AND RISK ASSESSMENT
    . Response predictive biomarkers – to differentiate between patient populations that have a greater potential to respond to the particular treatment in question (favorably or unfavorably), as opposed to those that are physiologically unlikely to have that response. These may identify subpopulations that can respond to a medical treatment in different ways. For example, they may correlate with an increased risk of drug toxicity, or an increased chance of drug benefit. Such biomarkers serve as a cornerstone in personalizing medicine, enabling practitioners to select the most appropriate treatment for individual patients/animal populations.
  • Prognostic biomarkers – that identify a baseline patient or disease characteristic that categorizes patients by degree of risk for disease occurrence or progression. A prognostic biomarker informs about the natural history of the disorder in that particular patient in the absence of a therapeutic intervention. Prognostic biomarkers may assist in targeting appropriate populations for inclusion in clinical trials or general practice treatment with the approved therapy.
  • Response identification biomarkers (pharmacodynamic biomarkers) – early post-treatment biomarkers that indicate the particular patient has shown some biological response to the treatment, and thereby has the potential to receive benefit as compared to those who have not shown that biological response and cannot benefit.
    >> RESPONSE IDENTIFICATION BIOMARKERS  
  • Biomarkers as surrogate endpoints in clinical trials to predict the clinical efficacy response to a treatment intervention. Surrogate endpoints may be of particular value in diseases where prolonged follow-up is required to determine the clinical outcome, such as neurodegenerative diseases, cancer, metabolic diseases, and infectious diseases that cause morbidity and mortality over a prolonged period of time. Surrogate endpoints may replace hard clinical end points as a measure of the effect of new therapies.
    >> BIOMARKERS AND SURROGATE ENDPOINTS
. SCIClips BIOMARKERS DATABASE :
 
A link to SCIClips cancer biomarker database with discovery, clinical and pre-clinical cancer biomarkers : periphal blood biomarkers, saliva biomarkers, urinary biomarkers, fecal biomarkers 
        >> SCIClips DATABASE

 

samedi 22 septembre 2012

PRESSURE CYCLING TECHNOLOGY (PCT)

. PCT PRINCIPLE : Pressure Cycling Technology (PCT) uses cycles of high and low pressure to break cells.
Video PCT (Pressure Bioscience) : http://www.pressurebiosciences.com/videos/video.html.

Use of PCT to break Legionnella cells : In the following study (see the poster at the link below) Pressure Bioscience Barocycler (model NEP3229) was used to break Legionella pneumophila Lens cells. After breakage by alternative cycles of high (30 000 psi) and low pressure the supension was subjected to RNA extraction and purification.

Poster : http://www.pressurebiosciences.com/downloads/3rdparty-2007-12/Poster-Barocycler.pdf

samedi 15 septembre 2012

Discovery of Essential Genes for Drug-Resistant Bacteria Reveals New Drug Targets

Biomedical scientists collaborating on translational research at two Buffalo institutions are reporting the discovery of a novel, and heretofore unrecognized, set of genes essential for the growth of potentially lethal, drug-resistant bacteria. The study not only reveals multiple, new drug targets for this human infection, it also suggests that the typical methods of studying bacteria in rich laboratory media may not be the best way to identify much-needed antimicrobial drug targets.
 

 
Journal reference : T. C. Umland, L. W. Schultz, U. MacDonald, J. M. Beanan, R. Olson, T. A. Russo. In Vivo-Validated Essential Genes Identified in Acinetobacter baumannii by Using Human Ascites Overlap Poorly with Essential Genes Detected on Laboratory Media. mBio, 2012; 3 (4): e00113-12 DOI: 10.1128/mBio.00113-12

dimanche 2 septembre 2012

New Cancer Drug Is Ten Times More Potent

http://www.sciencedaily.com/releases/2012/08/120829172113.htm







 
First implantation of Prototype Bionic Eye : Bionic Vision Australia researchers have successfully performed the first implantation of an early prototype bionic eye

http://www.sciencedaily.com/releases/2012/08/120831065003.htm