Monday, March 25, 2013

Repair Heart With Strangers’ Stem Cells?

Stem cells have the potential to become any type of cell in the body. Its ability of self-renewing or multiplying while maintaining the potential to develop into other types of cells makes them possible to become cells of the blood, heart, bones, skin, muscles, brain etc.
There are a number of adult stem cell therapies available, particularly bone marrow transplants that are used for treating leukemia. It is expected that stem cell therapies could eventually be used to treat various types of disease including cancer, Parkinson's disease, diabetes, heart failure, heart disease and other chronic ailments.
In contrast with previous findings, a study led by researchers from University of Miami found that stem cells donated by strangers could help restore heart tissues damaged by heart attack. The news was disclosed on November 6, 2012 during the American Heart Association’s (AHA) Scientific Sessions 2012. The findings were then published on December 12, 2012 in the ‘Journal of the American Medical Association’.
Only 30 patients in Miami and Baltimore were involved in the study. All of them had suffered heart attack years earlier, some as long as 30 years ago, and developed heart failure because the scar tissue from the heart attack had weakened their hearts making them unable to pump blood effectively.
Researchers advertised for people to supply marrow. A specific type of stem cells were removed from bone marrow using a needle into the hip and then amplified for about a month in a laboratory at Baltimore’s Johns Hopkins University. According to researchers, recipients would not reject these stem cells as they lack a key feature on their surface that makes the immune system see them as foreign tissue and attack them.
The cells were then returned to Miami and delivered through a tube pushed through a groin artery into the heart near the scarred area. Cells from own marrow were given to 15 patients and cells from strangers were given to the other 15.
After about a year, scar tissue had been reduced by about one-third. Improvements in how far patients could walk and in quality of life were noted in both groups. There was no significant difference on how well their hearts were able to pump blood.
This definitely is a breakthrough because cells supplied by others can now be used without blood or tissue matching. Cells could be made ready in the blood bank so needed patients could just come in for a therapy without much delay. Moreover, it is also cheaper to make the donor cells as a single marrow donor could supply enough cells to treat as much as 10 people.

Monday, March 18, 2013

Rising Stroke Cases Among Younger Age Groups

A stroke is the rapid loss of brain function as a result of disturbance in the blood supply to the brain. It is known as ischemic stroke when the cause is blockage in the arteries, or it is called hemorrhagic stroke when a blood vessel leaks or bursts. The latter is less common.
High blood pressure is the number one risk factor for strokes. The other major risk factors are diabetes, atrial fibrillation, high cholesterol, increasing age, heart disease, obesity, and family history of stroke. People aged beyond 55 used to be the likely victims for stroke, but it appears that stroke cases are rising among young and middle-aged adults.
According to a study of stroke rates in a 4-county region of Ohio and Kentucky, 12.9 percent of strokes occurred in adults in the age group between 20 and 55 in 1994 but the figure was increased to 18.6 percent in 2005.
In the paper published online on October 10, 2012 in journal ‘Neurology’, researchers from the University of Cincinnati College of Medicine in Ohio also showed that the average age of people who experienced a stroke fell from 71 in 1994 to 69 in 2005.
Researchers examined data on all stroke patients aged between 20 and 54 seen in hospitals, clinics and nursing homes during 3 separate, yearlong periods: July 1993 through June 1994, 1999, and 2005. They only included patient’s first stroke in the analysis.
It was found that the stroke rate among people aged above 75 declined from 1994 to 2005, which was agreed with other studies. For instance, the Framingham Heart Study reported a decrease in stroke rates between 1950 and 2004.
Such decline is no doubt encouraging but unfortunately, it is counterbalanced by the rising trend of younger strokes. Having stroke at younger ages means a greater loss of productive life years and greater health care expenses over time.
Reasons for the increase were not clear, but several findings revealed during the study period might explain the why. Surveys of people by other institutions in the same region showed an increasing number of people had high cholesterol. Moreover, data from national surveys also indicated an increased rate of diabetes, high cholesterol and obesity over the study period. The increase could also be partly due to better diagnoses of stroke using MRI as a diagnostic tool, according to some experts not involved in the study.

Monday, March 11, 2013

How About A Biological Pacemaker?

Pacemakers are, small devices placed in the chest or abdomen, used to treat arrhythmias. Arrhythmias are problems about the rate or rhythm of the heartbeat: the heart can beat too fast, too slow or with an irregular rhythm.

While most arrhythmias are harmless, some can be serious or even life threatening. The inability of the heart to pump enough blood to the body during arrhythmias could damage the brain, heart and other organs. By using electrical pulses, a pacemaker can prompt the heart to beat at a normal rate.

In a recent study, researchers from Cedars-Sinai Heart Institute in Los Angeles, California found that inserting a gene into ordinary heart cells of guinea pigs can turn the cells into rare biological pacemakers that regulate cardiac rhythm. The findings, which were published on December 16, 2012 in the journal ‘Nature Biotechology’, showed that out of a total 7 guinea pigs being injected with the virus, 5 later had heartbeats that were originated from their new pacemaker.

While 10 billion cells are found in the heart, fewer than 10,000 of them are pacemaker cells that can generate electrical activity to spread to other cardiac cells making the heart contract rhythmically and pump blood.

A virus was used to deliver human gene called Tbx18, whose normal role is to transform immature cells into pacemaker cells. These new cells generate electrical impulses spontaneously and were indistinguishable from native pacemaker cells. Tbx18 is normally active when pacemaker cells are formed during normal development in an embryo.

Besides limited battery life that require regular recharging, electronic devices also have other complications like displacement, breakage, entanglement of the leads that could be life threatening. Moreover, there are a growing number of patients contracting bacterial infection because of using electronic pacemakers. The biological pacemaker created, on the other hand, could solve most of these problems.

Building on the decade-long research into biological pacemakers, the technique has so far been tested on animals like pigs and rats. It is, however, expected this to work in humans as well. Hopefully in another 2 to 3 years, the technique can be used with the first target patients who have pacemaker device infection, according to researchers.

Until then, it is important that more studies should be carried out to understand if these findings could really help people with heart disease in the future.

Monday, March 04, 2013

Stay Away From Sugary Drinks To Prevent Stroke!

Numerous studies had shown that sugary drinks would lead to various health hazards including heart disease, obesity and diabetes. Such findings have prompted some legislative moves, for instance, ban is imposed in New York on super-sized sodas.
A group of researchers from Egypt and Japan conducted a study in Japan and found similar results. In their paper published on October 17, 2012 in ‘The American Journal of Clinical Nutrition’, they stated that women who consumed sugary drinks almost everyday were 83 percent more likely to develop ischemic stroke.
Ischemic stroke is a medical condition in which a blood vessel supplying blood to an area of the brain is blocked by a blood clot. It accounts for about 80 percent of all strokes, and it is the most common type of stroke in older adults.
In the study, only sugar-sweetened sodas and juices were considered as soft drinks, and so diet sodas or 100 percent fruit juices were excluded.
39,786 Japanese men and women aged between 40 and 59 years old answered a dietary, health and lifestyle questionnaire in 1990, 1995 and 2000. These participants were divided into 4 groups: those who rarely drank soft drinks, those who had 1 to 2 drinks a week, those who had 3 to 4 drinks a week, and those who had a soft drink almost everyday.
Until 2008, out of 11,800 women who rarely had a soft drink, 205 (1.7 percent) had an ischemic stroke. For 921 women who had a soft drink a day, 28 (3 percent) of them had such a stroke.
It could be the beverages’ effects on metabolism that raised the risk of stroke among women who favored soda drinking. High soft drink intake can cause weight gain, higher blood sugar and fats, as well as hypertension. This would in turn increase the risk of ischemic stroke.
However, no link between soft drink consumption and stroke risk was found in men. According to researchers, this could be because men with early signs of cardiovascular disease might have already reduced their intake of soda drink.
Meanwhile, the study did not find any association between soft drink and increased risk of heart disease. This probably because the underlying metabolic problems tied to soft drinks are more of a risk factor for stroke than for heart disease, as explained by researchers.