Tuesday, December 25, 2007

Statins and polyunsaturated fatty acids for treatment of atrial fibrillation stroke

Atrial fibrillation (AF) affects 1.5–2.0% of the population in the developed world. Projected data from population-based studies in the US indicate that the number of adults with AF will swell by 2.5–3.0-fold by 2050. Despite advances in pharmacological and nonpharmacological therapies for rhythm or rate control in patients with AF, primary prevention with 'upstream' therapy and risk factor modification is likely to produce a far greater effect in the general population than specific interventions. Rapidly developing experimental work has provided new insights into AF pathophysiology that will lead to new mechanism-based therapies. Agents targeting inflammation, oxidative injury, atrial myocyte metabolism, extracellular matrix remodeling, and fibrosis, have theoretical advantages as novel therapeutic strategies. Angiotensin-converting-enzyme inhibitors, angiotensin-receptor blockers, beta-blockers, statins, and omega-3 polyunsaturated fatty acids have shown antiarrhythmic potential, over and above any effect related to the treatment of underlying heart disease. These agents could be exploited to prevent or delay atrial remodeling in patients with AF, even in the absence of routine indications for such therapy. This Review provides a contemporary evidence-based insight into the possible preventive and reverse remodeling roles of statins and polyunsaturated fatty acids in AF.


Saturday, December 22, 2007

New Hypertension Drug - Bystolic

A new beta blocker called Bystolic (nebivolol) has been approved for treatment of high blood pressure (hypertension), the U.S. Food and Drug Administration announced Monday.
The approval was based on findings from four studies in which more than 2,000 people received Bystolic. The drug's efficacy was similar to that of other FDA-approved beta blockers. Common side effects experienced by people taking Bystolic included headache, fatigue, dizziness and diarrhea.
Beta blockers are a well-established class of medications that lower blood pressure by reducing the force with which the heart pumps blood. Nearly one in three American adults has high blood pressure, which increases the risk of stroke, heart failure, heart attack, kidney failure and death.

Friday, December 07, 2007

Fruits and vegetables reduce the risk of certain cancers

Fruits and vegetables have long been known to help reduce the risk of certain cancers. Based on prior research, the American Cancer Society recommends eating five servings of fruits and vegetables daily.
In the first study, Ohio State University researchers found black raspberries may protect against esophageal cancer by reducing the oxidative stress that results from Barrett's esophagus, a precancerous condition usually caused by gastroesophageal reflux disease. The esophagus is a long tube that connects the throat to the stomach. Reflux disease causes stomach acid to continually splash back up into the esophagus.
People with Barrett's esophagus typically are 30 to 40 times more likely to develop esophageal cancer, which has a poor five-year survival rate of 15 percent.
Black raspberries previously have been shown to reduce the risk of oral, esophageal and colon cancer in animal models, according to the researchers, who called for further study in humans.

In other research presented at the meeting, broccoli sprouts and cruciferous vegetables both showed promise in the fight against bladder cancer.

A second team at the institute found that people who ate three or more servings of raw, cruciferous vegetables per month reduced their risk of bladder cancer by 40 percent. Cruciferous vegetables include broccoli, cabbage and cauliflower.

The team analyzed the dietary habits of 275 people with early bladder cancer and 825 people who were cancer-free. The researchers specifically asked how many servings of raw or cooked cruciferous vegetables they ate before their diagnosis and whether they smoked.

Analysis of the data showed that the more raw, cruciferous vegetables people ate, the lower their risk of bladder cancer. In comparison to people who smoked and ate fewer than three servings of raw vegetables a day, nonsmokers eating at least three servings of cruciferous vegetables daily were 73 percent less likely to develop bladder cancer.

Wednesday, November 07, 2007

Cancer: Reovirus plus Radiation

Since the advent of cancer therapy, clinicians and patients have sought more targeted treatments that attacked tumors while sparing normal tissues. Several viruses, including the reovirus, or Respiratory Enteric Orphan virus, have shown a strong preference for killing cancer cells vs. normal cells. These oncolytic (tumor-bursting) viruses represent an entirely new approach to cancer treatment.
Calgary-based Oncolytics Biotech has recently reported encouraging results from a U.K. Phase Ia/Ib clinical trial with its Reolysin® oncolytic reovirus formulation in combination with radiation for patients with a variety of advanced or metastatic cancers. The rationale for the trial emerged after preclinical work demonstrated that the addition of radiation enhanced the cancer-killing ability of Reolysin. Interim results from the Phase Ia/b human study suggest this is true.
The study has treated 22 middle-aged and elderly patients with various tumor types to date. Patients were split into two groups that received either 20 or 36 Gy of radiation, along with escalating dosages of two to six injections of REOLYSIN into a target tumour. Tumors included melanomas and cancers of the colon, pancreas, ovaries, larynx, and other sites. No serious or dose-limiting side effects were noted. Although this safety study was not designed to show tumor shrinkage, investigators noted a positive trend towards efficacy. Of the 11 patients in the Ia study, three experienced significant partial responses. Three of the 6 patients who completed the Ib trial also responded to treatment. Typically, only 5% to 15% of patients with advanced cancer respond to conventional cancer treatments. These particular patients had cancers that either did not respond to cancer treatment, or for whom no other treatments were available.
Reovirus is a double-stranded RNA virus that causes asymptomatic human infection. When it encounters cancer cells, reovirus invades and produces thousands of copies of itself, causing the cell to burst. The reovirus selectivity is based on its ability to exploit a pathway specific to cancer cells. Specifically, reovirus only infects cells that possess ras, an activated cancer signaling pathway that operates in about 70% of human cancers. Ras acts as a kind of switch to allow reovirus to invade and destroy the cell. Normal cells keep ras (the name of both a gene and its protein product) in check; cancer cells lose control over Ras, resulting in the uncontrolled growth characteristic of deadly tumors.

Friday, October 26, 2007

Cervical Cancer Risk

Precancerous Lesions Raise Cervical Cancer Risk

Women who have had advanced precancerous lesions of the cervix are still at risk for invasive cancers up to 25 years later.
Currently, the American Cancer Society recommends that women who have had precancerous lesions called severe dysplasia/carcinoma in situ (CIS) continue getting Pap tests for 10 years after treatment. But, based on this study, these guidelines may need to be changed.
The study was led by Dr. Bjorn Strander, a senior consultant with the Department of Obstetrics and Gynecology at Sahlgren's Academy at the University of Gothenburg. The researchers collected data on 132,493 women who had a diagnosis of severe dysplasia/CIS between 1958 and 2002. The statistics came from the National Swedish Cancer Register.

The researchers found 881 women had developed cervical cancer, and 111 had developed vaginal cancer more than one year after the initial diagnosis. This was almost seven times higher than expected

Women with a diagnosis of severe dysplasia/CIS were more than twice as likely to develop cancer compared with the general female population. The women were also twice as likely to develop invasive cervical cancer after diagnosis of CIS if that diagnosis was made between 1991 and 2000, compared with the same diagnosis made from 1958 to 1970. This increased risk might be due to changes in treatment over that period, particularly because fewer hysterectomies are being done as part of treatment for CIS
Strander's team also found a particularly high risk for women over age 50, and this risk continued to increase with age.