Tuesday, October 9, 2007

The Nobel Prize in Physiology or Medicine 2007

The Nobel Prizes in Physiology or Medicine for the year 2007
have been anounced to

Dr Mario R. Capecchi , USA
Dr Sir Martin J. Evans , UK
Dr Oliver Smithies , USA
"for their discoveries of principles for introducing specific gene modifications in mice by the use of embryonic stem cells"

They have made a series of ground-breaking discoveries concerning embryonic stem cells and DNA recombination in mammals. Their discoveries led to the creation of an immensely powerful technology referred to as gene targeting in mice. Gene targeting is often used to inactivate single genes. Such gene "knockout" experiments have elucidated the roles of numerous genes in embryonic development, adult physiology, aging and disease.

Capecchis research has uncovered the roles of genes involved in mammalian organ development and in the establishment of the body plan. His work has shed light on the causes of several human inborn malformations.

Evans applied gene targeting to develop mouse models for human diseases. He developed several models for the inherited human disease cystic fibrosis and has used these models to study disease mechanisms and to test the effects of gene therapy.

Smithies also used gene targeting to develop mouse models for inherited diseases such as cystic fibrosis and the blood disease thalassemia. He has also developed numerous mouse models for common human diseases such as hypertension and atherosclerosis.

Almost every aspect of mammalian physiology can be studied by gene targeting. In summary, gene targeting in mice has pervaded all fields of biomedicine. Its impact on the understanding of gene function and its benefits to mankind will continue to increase over many years to come.

Read More at the Press Release by Nobelprize.org

Read a summary of their work : 'Speedread'

Monday, October 1, 2007


Blood cultures in paediatric patients: A study of clinical impact

Indian Journal of Medical Microbiology,

Year : 2007 Volume : 25 Issue : 3 Page : 220-224
Murty DS, Gyaneshwari M

Correspondence Address:
Murty D S
Department of Microbiology, SV Medical College, Tirupati, Andhra Pradesh India

Purpose :
Blood cultures form a critical part of evaluation of patients with suspected sepsis. The present study was undertaken to study the risk factors, duration of incubation for obtaining positive cultures, and the clinical impact of the culture report. Methods : A total of 220 samples from 107 pediatric patients presenting with suspected bacteraemia were processed aerobically.
Results :
Cultures were positive in 18.7% of the samples. Most of the positive cultures were obtained after 24 hours of incubation of the broth and no isolates were obtained beyond day 4 of incubation. Therapy was modified in 54.23% of the patients after receipt of culture report.
Conclusions :
Incubation beyond four days (unless with specific indication like enteric fever) may be unnecessary for issuing a negative culture report. Repeated isolation of doubtful pathogens confirms true bacteraemia. Early culture report increases therapeutic compliance.

Read full article at Indian Journal of Medical Microbiology