Thursday, December 25, 2008
Thum and colleagues discovered that miR-21 was expressed in the heart's fibroblast cells (cells that make the scaffolding of collagen or connective tissue that hold the shape of the organ) and were in greater numbers in lab mice bred to have heart failure and also in human tissue from patients who had heart failure.
In this study they showed that increasing expression of miR-21 changed the way that signals behaved in a previously unknown stress response pathway that involved the gene sprouty-1 and the MAP-kinase signaling pathway. In turn, increasing the activity of the MAP-kinase pathway led to a number of signs of heart failure, such as enhanced fibroblast survival, increased secretion of factors like fibroblast growth factor, tissue scarring (fibrosis), and cardiac dysfunction including cellular hypertrophy.
The researchers proved they could administer anti-miR-21 effectively to the heart by monitoring it with fluorescence staining. Then, in a mouse transaortic constriction model of human heart failure, they showed that anti-miR-21 silenced increased expression of miR-21 and corrected downstream changes in sprouty-1 and MAP-kinase signaling.
The interesting thing is their conclusion : Anti-miR-21, showed the most statistically significant improvement in the heart failure mouse model when given before induction of heart failure and for as long as three weeks afterward and it might be possible to target entire disease pathways with one drug. Contrats Dr. Thomas Thum.
Sunday, December 21, 2008
When we see the presently available NSAIDs, most of them have ulcerogenicity as one of the common side effect. Ulcerogenicity can be explained by the metabolism of Arachidonic acid into various metabolites. Most of the drugs (NSAIDs) act by inhibiting the prostaglandins. But some of the prostaglandins are essential as cytoprotective layer and hence selective inhibitors of Cyclooxygenase –II (COX-II) and 5-LO (Lipoxygenase) are better tolerable and hence we can call these drugs as non ulcerogenic NSAIDs. Though these 2 enzymes (COX-II and 5-LO) were the targets of many drug discovers (as for as my knowledge goes, 1996-98 there were many papers regarding the selective inhibitors).
Now Oliver Werz and co workers have come with some new compounds 2-(4-(biphenyl-4-ylmethylamino)-6-chloropyrimidin-2-ylthio)octanoic acid (with some structural variations like α substitution with extended n-alkyl or bulky aryl substituents and concomitant replacement of the 2,3-dimethylaniline by a biphenyl-4-yl-methane-amino residue) a derivative of pirinixic acid [PA, 2-(4-chloro-6-(2,3-dimethylphenylamino) pyrimidin-2-ylthio)acetic acid.
Significance of this research is the, less pronounced inhibition of cyclooxygenases-1/2. Taken together, these pirinixic acid derivatives constitute a novel class of dual mPGES-1/5-LO inhibitors with a promising pharmacologial profile and a potential for therapeutic use. More……
Saturday, December 20, 2008
If we think back how, the killer illnesses such as cancer and Alzheimer's begin and are they anything to do with fundamental mechanisms of epigenetic control ? Dr. Stephen Michnick and group says, "control of genes is subject to both inherited and environmental factors, so that genes may be read differently and up to what a person eats or even what their grandmother ate” - something we all, try to find comparisons between our children with our parents.
In the PLoS study, the researchers identified proteins they described as gene grammarians. Gene grammarians are linked to a larger complex of proteins that determine whether a gene can be read – or not – based on DNA structure. The scientists found gene grammarians can determine whether cells have different functions and can identify the different levels of susceptibility – or resistance – individuals could have to specific diseases.
The study provides insight into the fundamental mechanisms of epigenetic control – gene expression that are controlled by heritable but potentially reversible changes in DNA – which provides a new avenue towards understanding environmental effects on the human genome and I hope this study will have some impact on genetically transmitted deceases……
Friday, December 19, 2008
When ever I see a advertisement with “real enzymes” for any dish wash bar/liquids or soap powder, used to wonder what are these enzymes and how they really work and is there any difference between them (for dish washing bar and soap powders). Thanks to Guillermo et. al., who have come up with a interesting way of differentiating the types of enzymes by a method, which is based on the acid hydrolysis of the enzymes to their amino acid constituents. It is really interesting, since their first tentative introduction as minor additives in cleaning products.they have become major players. Cleaning enzymes have almost reduced the use of bleaching agents (hypochlorite solution). The advantage of these enzymes (over the bleaching agents) is better fabric care, during washing. I am sure this test will have its impact in the future, on the magical ability of the enzymes to remove so many types of marks and stains by its equally impressive way of classifying the enzymes involved.
Four types of enzymes:
1. Proteases- attack protein-rich stains such as grass and blood;
2. Amylases- remove stains that contain starch from dishes and fabrics
3. Lipases- hit fats and edible oils and
4. Cellulases- removes the fuzz balls that form on cotton
Hope this experiment will go a long way in adding more enzymes…….
Sunday, December 14, 2008
DNA strands can be easily converted into tiny fibre optic cables that guide light along their length. Optical fibres made this way could be important in optical computers, which use light rather than electricity to perform calculations, or in artificial photosynthesis systems that may replace today's solar panels, claims Bo Albinsson
Though the result is similar to natural photonic wires found inside organisms like algae, where they are used to transport photons to parts of a cell where their energy can be tapped. In these wires, chromophores are lined up in chains to channel photons. It is really interesting though there are pros and cons about the claim. Hope further research in the same, will definitely substantiate the claim…..
Yes, says Stephen O'Brien and colleagues from the National Cancer Institute in
I am sure this research could go a longway in determining, when an individual should start HIV therapy (start HAART earlier than currently recommended) and also help the doctors choose the best combination of drugs.
Thursday, December 11, 2008
Everything Nano…now it is the turn of fungus. German researchers, Alexander Eychmüller and Karl-Heinz Peacute have discovered that they can coat the thin fronds that grow from Penicillium and other fungi with nanoscopic particles of a noble metal. They found that fungal threads coated with 200 nm gold particles appear reddish brown, as does a solution of such gold nanoparticles, providing evidence that the nanoparticulate nature of the particles is maintained during growth rather than aggregation to form larger units taking place. For more….
Tuesday, December 9, 2008
Lactose intolerance, bulging brains in humans and lacking of a mutation associated with increased fertility - the answers for all these questions are being answered by microcephaln – a gene mutation. Neanderthal genome researchers, have half done the job and I am sure this will shed light on the evolution of modern humans after their ancestors split from Neanderthals, more than 600,000 years ago and hope they will achieve the success soon.....