Thursday, December 17, 2009

Synthetic platelets halt blood-clotting time....

Lavik and co workers made platelets from polymers already used in treatments approved by FDA. They also built the parts of the synthetic platelets that bind to natural platelets from relatively short pieces of proteins (asthey're more stable than longer pieces and cheaper). To avoid formation of an artificial clot, each synthetic platelet is built with a surrounding water shield. Fluorescing compounds showed the synthetic platelets not bound in clots were flushed from the rat model's system in a day. No ill effects were seen in the following week......

More.....Synthetic platelets halt blood-clotting time

Nilotinib more efficiant over Imatinib for (Ph+ CML)....

Nilotinib (see structure) :

Nilotinib, in the form of the hydrochloride monohydrate salt, is a tyrosine kinase inhibitor, approved as Tasigna in USA and the EU for drug - resistant chronic myelogenous leukemia (June 2006), resistant to treatment with imatinib (Gleevec), another tyrosine kinase inhibitor currently used as a first-line treatment.

In a recently held large clinical trial, nilotinib demonstrated greater efficacy over the current gold standard treatment, imatinib, in adult patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukaemia (Ph+ CML) in the chronic phase.

As per the claim by the researchers, in the first head-to-head study of these two oral treatments as initial therapy for this life-threatening leukaemia, nilotinib demonstrated statistically significant improvement over imatinib in key measures of effectiveness used in the trial. The trial showed that at 12 months, significantly fewer patients on nilotinib 300mg twice-daily progressed from the initial chronic phase of the disease to the later accelerated or blast crisis phases than those on imatinib 400mg once-daily. This demonstrates that nilotinib provided significantly better control of the disease compared to imatinib.

95% of patients with CML have an abnormality known as the Philadelphia chromosome. This chromosome produces a type of protein called Bcr-Abl, which is responsible for the overproduction of the cancerous white blood cells that are the main feature in Ph+ CML. Nilotinib is a potent and selective inhibitor of the Bcr-Abl protein, thereby inhibiting the production of these cancerous cells.

Ref : http://www.novartis.com/newsroom/media-releases/en/2009/1359764.shtml

Wednesday, December 16, 2009

Lidocaine IV injection as pain killer after ambulatory surgery ?

We know that, Lidocaine or lignocaine is a common local anesthetic and antiarrhythmic drug. Lidocaine is used topically to relieve itching, burning and pain from skin inflammations, injected as a dental anesthetic or as a local anesthetic for minor surgery.

Now researchers from University of Virginia, Charlottesville, have come up with interesting info about the same drug. As per the claim by the researchers low doses of lidocaine given intravenously can help to control pain after common ambulatory surgery procedures. Intravenous lidocaine may offer a safe, inexpensive, and effective option for improving pain control after minimally invasive or minor surgery, reports the new study led by Dr Danja S. Groves of University of Virginia, Charlottesville. The results are surprising, because local anesthetics such as lidocaine are usually injected close to the nerve to numb the area for surgery. Though the anestheas (higher dose) are toxic, previous studies have found that that IV lidocaine injection is safe in small doses. Though the mode of action and anti inflammatory activity are still to be expalined, is a good achievement...

Ref : http://www.newswise.com/articles/view/559452/

Tuesday, December 15, 2009

Combination of Lapatinib and Trastuzumab a better treatment for breast cancer....

Lapatinib or lapatinib ditosylate is an orally active chemotherapeutic drug treatment for solid tumours such as breast cancer. Patients who meet specific indication criteria may be prescribed lapatinib as part of combination therapy for breast cancer. On March 13, 2007, FDA approved lapatinib in combination therapy for breast cancer patients already using capecitabine.

Recently, researchers from Duke University Medical Center. Dr. Kimberly Blackwell have found more interesting results when they did try the combination of Trastuzumab (monoclonal antibody). As per the claim by the researchers, Lapatinib plus trastuzumab are significantly better than lapatinib alone in extending the lives of breast cancer patients whose tumors are HER2-positive.

Blackwell says, the combination targeted therapy gave patients more than a four-month survival advantage over those who took lapatinib alone. She says the findings may be the first step toward a chemotherapy-free future. This is the first time that a pair of targeted therapies has been shown to be superior to any intervention that paired a targeted therapy with a hormonal or chemotherapy based approach, she said. The interesting claim by the researchers trastuzumab binds to and blocks part of the HER2 growth factor that appears on the surface of some breast cancer cells while lapatinib binds to a second growth factor, EGFR, and part of HER2 that sits below the cell surface. It's sort of a double whammy, disabling the HER2 protein in two places instead of one......

Ref : http://www.dukehealth.org/health_library/news/targeted_therapy_prolongs_life_in_patients_with_her2_positive_breast_cancer

Monday, December 14, 2009

Methotrexate & Ocrelizumab combination a new hope for RA patients....

In recent days, I have seen many researchers are trying the combination of existing drugs in combination with a monoclonal antibodies for many diseases like cancer, rheumatoid arthritis and are successful too. As synthetic chemist I was interested in knowing about these monoclonal antibodies and found some interesting info, which I am sharing herewith...

About monoclonal antibodies :

monoclonal antibodies (mAb or moAb) are monospecific antibodies that are identical because they are produced by one type of immune cell that are all clones of a single parent cell. Given almost any substance, it is possible to create monoclonal antibodies that specifically bind to that substance; they can then serve to detect or purify that substance. This has become an important tool in biochemistry, molecular biology and medicine. When used as medications, the non-proprietary drug name ends in -mab.

The invention is generally accredited to Georges Köhler, César Milstein, and Niels Kaj Jerne in 1975; who shared the Nobel Prize in Physiology or Medicine in 1984 for the discovery. The key idea was to use a line of myeloma cells that had lost their ability to secrete antibodies, come up with a technique to fuse these cells with healthy antibody-producing B-cells, and be able to select for the successfully fused cells. In 1988 Greg Winter (Nat Rev Cancer 2001;1:118-129) and his team pioneered the techniques to humanize monoclonal antibodies, removing the reactions that many monoclonal antibodies caused in some patients. Interestingly, many monoclinical antibodies have been tried for rheumatoid arthritis, chrohn's disease and as anticancer agents.

Many monoclonal antibodies like infliximab, etanercept and adalimumab were tried for the rheumatoid arthritis now its interseting to note that Genentech and Biogen Idec reported positive outcome from ocrelizumab ( humanized anti-CD20) -MTX (Methotrexate - see the structure : this drug is a part of DMARD treatment meant for RA patients) combination study in RA. The results are significant because they are the first data from a large Phase III trial to show that a humanized antibody targeted at B-cells improves the signs and symptoms of rheumatoid arthritis. Hope patients suffering from RA and those are not responding will breathe a sigh of relief in the days to come...

Ref : http://www.gene.com/gene/news/press-releases/display.do?method=detail&id=12487

Sunday, December 13, 2009

Bisphosphonates play a role in reducing recurrent breast cancer....


We know that bisphosphonates (also called diphosphonates) are a class of drugs that prevent the loss of bone mass, used to treat osteoporosis and similar diseases. Bone has constant turnover, and is kept in balance (homeostasis) by osteoblasts creating bone and osteoclasts digesting bone. Bisphosphonates inhibit the digestion of bone by osteoclasts. Osteoclasts also have constant turnover and normally destroy themselves by a process called cell suicide (apoptosis). Bisphosphonates encourage osteoclasts to undergo apoptosis. Though other uses like in he treatments of osteoporosis, osteitis deformans, bone metastasis, primary multiple myeloma,hyperparathyroidism and osteogenesis imperfecta were known. A new data suggests that these agents may play a role in reducing recurrent breast cancer as well. Zoledronic acid (see the structure) is both safe and effective in preventing bone loss in postmenopausal women with breast cancer who are treated with aromatase inhibitors, according to data presented at the CTRC-AACR San Antonio Breast Cancer Symposium. Women who take aromatase inhibitors need some sort of bone protection, and this five-year data show that zoledronic acid is a viable option.

As per the claim by the researchers lead by Dr. Adam Brufsky , women who are on Medicare tend to go with tamoxifen because the cost of anastrozole puts them squarely in the donut hole of Medicare Part D, but once the cost barrier is removed there will likely be a mass switch to the aromatase inhibitor, which will necessitate the need for bone protection. More interestingly, in the same conference a research group lead by Rowan Chlebowski presented a study wherein "women who used bisphosphonates, had significantly fewer invasive breast cancers than women who did not use bisphosphonates. .......

http://www.upci.upmc.edu/news/upci_news/121009_study.cfm

Saturday, December 12, 2009

Xanthohumol may help in preventing prostate cancer....

We know that Xanthohumol is a Xanthone (phenylated chalcone or Phenylflavonoid). Xanthohumol was initially detected in an extract(series of Humulones) from Hops (Humulus lupulus) and is present in beer. This prenylated flavonoid has been shown to be a potent bioactive compound. Xanthohumol has been shown to have antiproliferative and cytotoxic effects in human cancer cell lines. It has also been displayed to inhibit diacyl glycerol acetyl transferase (DGAT) and human P450 enzymes. Xanthohumol inhibits the expression of HIF-1a and VEGF under hyposic conditions.

Higher antioxidant activity is reported for prenylchalcones than for prenyl flavanones in the Cu2+- mediated oxidation of LDL, suggesting a relation between structure and function. Also, many chalcones suppress tumor promotion more effectively than flavonoids themselves.

Quantities of xanthohumol found in Hop are to small to have any biological effects under normal consumption amounts. Some of the researchers also claims that it has got anti-HIV-1 activity too.

Now researchers from German Cancer Research Center, in Heidelberg, Germany, have come up with more interesting result, i.e., Xanthohumol may aid in preventing prostate cancer. As per the claim by the authors, the compound blocks the effects of the male hormone testosterone.

Studies to date have shown that xanthohumol blocks the action of estrogen by binding to its receptor, which may lead to prevention of breast cancer. Since testosterone receptors act similarly to that of estrogen — by binding, then stimulating hormone-dependent effects, such as gene expression and cell growth — the researchers examined whether xanthohumol might not only block the effects of estrogen, but also of the male hormone androgen. Xanthohumol prevented the receptor from translocating to the cell nucleus, thus inhibiting its potential to stimulate the secretion of PSA and other hormone-dependent effects.

The interesting part of their research is the molecular modeling results, which showed that xanthohumol directly binds to the androgen receptor structure. The researchers suggest that this compound may have beneficial effects in animals — when they measured the anti-androgenic potential of xanthohumol in a rat model, they found that although xanthohumol was not able to prevent an increase in prostate weight after testosterone treatment, it could reduce testosterone-increased seminal vesicle weight.

As per the claim by the researchers the prostate weights were not changed, xanthohumol still reduced the effects of hormone signaling, such as gene expression, measured in the prostate tissue...

Ref : http://mct.aacrjournals.org/content/1/11/959.full

Friday, December 11, 2009

Carfilzomib for multiple myeloma ?

The proteasome has emerged as an important target for cancer therapy with the approval of bortezomib, a first-in-class, reversible proteasome inhibitor, for relapsed/refractory multiple myeloma (MM). However, many patients have disease that does not respond to bortezomib, whereas others develop resistance, suggesting the need for other inhibitors with enhanced activity. Therefore the researchers evaluated a novel, irreversible, epoxomicin-related proteasome inhibitor - Carfilzomib.

The second-generation proteasome inhibitor carfilzomib is showing noteworthy response rates and low levels of adverse side effects among multiple myeloma patients in a phase II clinical trial.

The updated data from the 17-site study focuses on patients with relapsed or resistant multiple myeloma who have received one to three prior therapies, but not the drug bortezomib, the original proteasome inhibitor. The results are of grat importance because of the fact that multiple myeloma is an incurable, challenging disease with devastating consequences. While new agents are extending life expectancies, they often have adverse side effects, including severe neuropathy. Carfilzomib is showing good response rates, with an improved side effects, except for minor, included fatigue, nausea and anemia.

Ref : http://bloodjournal.hematologylibrary.org/cgi/content/full/110/9/3281/F1

Thursday, December 10, 2009

MSRA can be stopped before it becomes dangerous ....

In continuation of my update on MRSA (methicillin-resistant Staphylococcus aureus), I found the following info interesting.

C. Jeffrey Brinker research group has determined that the very first stage of staph infection, when bacteria switch from a harmless to a virulent form, occurs in a single cell and that this individual process can be stopped by the application of a simple protein (as against the belief that, staph infections are caused by many bacterial cells that signal each other to emit toxins. The signaling process is called quorum sensing). The most significant results from the researchers are :

1. isolation of Staphylococcus aureus bacteria in individual (isolation of an individual bacterium
previously had been achieved only computationally);

2. demonstration of release of signaling peptides from a single cell, not a quorum &

3. introduction of an inexpensive, very low-density lipoprotein (VLDL) to bind to the
messenger peptide, they stopped the single cell from reprogramming itself.

One aspect of experimental rigor was the team's ability to organize living cells into a nanostructured matrix. The researchers has already done it with yeast, and just extended the process to bacteria. Researchers are optimistic about finding a mechanism to locate bacteria reprogramming in the body so that the antidote can be delivered in time. If they achieve what they are optimistic, so there will selectivity of targeting the bacteria (human gastro-intestinal system contains many useful bacteria) which in my opinion will be a remarkable feat....

Ref : http://www.nature.com/nchembio/journal/vaop/ncurrent/full/nchembio.264.html

Wednesday, December 9, 2009

Anticancer & Antiinflammatory properties of Lunasin (Soy Peptide) established ?...

We know that many researchers have tried to establish the anticancer activity of the peptide lunasin (which has been already accepted as neutraceutical agent). Now researchers from University of Illinois have come up with more interesting facts, Soy peptide often discarded in the waste streams of soy-processing plants, may have important health benefits that include fighting leukemia and blocking the inflammation that accompanies such chronic health conditions as diabetes, heart disease, and stroke.

The researchers confirmed lunasin's bioavailability in the human body by doing a third study in which men consumed 50 grams of soy protein--one soy milk shake and a serving of soy chili daily-for five days. Significant levels of the peptide in the participants' blood give us confidence that lunasin-rich soy foods can be important in providing these health benefits.

In the cancer study, de Mejia's group identified a key sequence of amino acids- arginine, glycine, and aspartic acid, (the RGD motif)--that triggered the death of leukemia cells by activating a protein called caspase-3. The scientists also verified lunasin's ability to inhibit topoisomerase 2, an enzyme that marks the development of cancer, and they were able to quantify the number of leukemia cells that were killed after treatment with lunasin in laboratory experiments.

More interesting out come of their study is lunasin's potential anti-inflammatory activity, (first time) they showed that lunasin blocked or reduced the activation of an important marker called NF-kappa-B, a link in the chain of biochemical events that cause inflammation. They also found statistically significant reductions in interleukin-1 and interleukin-6, both important players in the inflammatory process (the reduction in interleukin-6 was particularly strong). As per the claim by the group, although the high cost of obtaining lunasin from soy waste limits its use for nutritional interventions, soy flour does contain high concentrations of the peptide (depending on some genotype soy).

Its good see the diverse activities associated with Soy......

Source : http://pubs.acs.org/doi/abs/10.1021/jf803303k?prevSearch=Elvira%2Bde%2BMejia&searchHistoryKey=