Research Topic #3

Harvard Study Links Teen Obesity in Girls to Increased Risk of Developing MS

A study of more than 200,000 female nurses suggests that those who were obese at the age of 18 were twice as likely to develop MS later in life. Obesity during earlier childhood or in adulthood was not associated with increased MS risk. Based on this study in women, it is not clear whether the same would hold true for teenaged boys. Kassandra L. Munger, ScD, Alberto Ascherio, MD, DrPH, and colleagues (Harvard School of Public Health, Boston) report their findings in Neurology (2009;73:1543-1550).

Background: While MS is not contagious or directly inherited, epidemiologists—the scientists who study patterns of disease—have identified factors in the distribution of MS around the world that may eventually help determine what causes the disease. These factors include gender, genetics, age, geography, and ethnic background. This study explores whether weight is a factor that affects MS risk.

The Study: The Harvard team collected information from women aged 25 to 42 who enrolled in the Nurses’ Health Study (a cohort of 121, 700 female registered nurses) and Nurses’ Health Study II (116,671 female nurses). During the course of the study, women reported their height and weight currently, and at age 18, and if there was a diagnosis of MS. Also, women selected a silhouette that described their body size at ages 5, 10, and 20. The investigators computed the body mass index (BMI), a measure of body fat based on height and weight. A BMI greater than or equal to 30 (kg/m2) is considered obese. Over the course of 40 years of follow-up, 444 cases of definite MS and 149 cases of probable MS developed among the nurses.

Women who had a BMI of more than 30 at age 18 were more than twice as likely to develop MS. Having a large body size (based on silhouettes) at age 5 or 10 was not associated with an increased MS risk, but a large body size at age 20 was associated with a 96% increase in MS risk. Adult BMI was not associated with increased MS risk.

Comment: Based on this study in women, it is not clear whether the same would hold true for teenaged boys. The authors comment that while a strength of this study is the large sample size, the reliance on “self-report” is a limitation. They hypothesize that if an association between teen obesity and MS is confirmed, a possible biologic mechanism might be the lower levels of vitamin D associated with obesity. Growing evidence indicates that vitamin D may help protect against the development of MS.

Research Topic #2

Researchers Show How Immune Attack May Directly Damage Nerve Fibers in MS

Researchers report on a protein that may engage the immune attack to target nerve fibers in MS; studies suggest that damage to nerve fibers may be the root cause of long-term disability in MS. Edgar Meinl, MD (Max Planck Institute of Neurobiology, Martinsried, Germany) and colleagues reported their findings in Proceedings of the National Academy of Sciences USA, (2009 May 19;106(20):8302-7). This study was funded by the MS Society of Great Britain and Northern Ireland, among others.

Background: Multiple sclerosis occurs when the immune system attacks and damages the brain and spinal cord, with a major target being the myelin that ensheathes nerve fibers. Recent research indicates that damage to nerve fibers themselves may occur early and contributes to long-term disability in people with MS. But it is not clear how nerve fibers are damaged in the course of the immune attack, or whether they are directly targeted by the immune system.

The Study: First, Dr. Meinl’s team used proteomics – technology that scans thousands of proteins at once – to identify antibodies (immune proteins that target specific molecules) in brain tissue from people with MS that react to nerve fiber components. This process highlighted a protein called “contactin-2/TAG-1” (transiently expressed axonal glycoprotein 1). Contactin-2/TAG-1 is active on nerve cells, in the region where myelin connects with the nerve fibers.

They then compared the reactivity of immune T cells from individuals with MS and other disorders by exposing their T cells to Contactin-2/TAG-1. They found that T cells from people with MS showed signs of “recognizing” and mounting immune responses to this molecule, and also found evidence of antibodies in MS spinal fluid that reacted to this molecule.

Research Topic — MS

Multiple sclerosis (or MS) is a chronic, often disabling disease that attacks the central nervous system (CNS), which is made up of the brain, spinal cord, and optic nerves. Symptoms may be mild, such as numbness in the limbs, or severe, such as paralysis or loss of vision. The progress, severity, and specific symptoms of MS are unpredictable and vary from one person to another. ("What is Multiple sclerosis")
Although there is still no cure for MS, effective strategies are available to modify the disease course, manage symptoms, improve function and safety, and provide emotional support. In combination, these treatments enhance the quality of life for people living with MS. ("Treatment")


Panel Recommends that FDA Approve Fampridine-SR (proposed name Amaya) for Symptomatic Treatment of MS

A U.S. Food and Drug Administration advisory committee today recommended that the agency approve marketing of Fampridine-SR (Acorda Therapeutics, with a proposed name change to Amaya) for its ability to improve walking speed in people with any type of multiple sclerosis. While the FDA is not required to follow the recommendations of its advisory committees, it usually does. The agency is expected to make a final decision about whether to approve the drug for market on or before the target date of October 22, 2009.

Background on Unmet Need: Problems with gait (difficulty in walking) are among the most common limitations in MS. While there are six FDA-approved disease-modifying therapies that are at least partially effective against some forms of the disease, as well as rehabilitation and symptomatic treatments for some symptoms, at present there is no pharmacologic treatment specifically available for MS-related difficulty walking. This disability has wide-ranging effects on people’s lives, even in its milder manifestations.

A recent survey among more than 1,000 individuals with MS and many of their family members examined the impact of mobility issues, such as difficulty walking, on quality of life among patients with MS and their families. Some two-thirds of patients reported difficulty walking and of these, 70% reported that such difficulty was the most challenging part of their MS, and most reported that difficulty walking restricts their daily activities significantly, including their ability to travel. ( Read more about survey results) ("Panel")

Photosynthesis Blog

Photosynthesis matters to me because without photosynthesis the world we know today would not exist. There would be no plants or animals. 
One resource that I found helpful in understanding photosynthesis was this website. It was clear and easy to navigate. The animations are interactive and it shows and explains the different parts of photosynthesis.    

Clouds

I know the basics of clouds like, that they are made up of frozen water crystals, and there are various types, such as stratus, cirrus, and cumulous. I really want to learn about how they are formed and what causes the different formations and if clouds are affected by rain causing bacteria. 

Here are some pictures I've taken of clouds:   (click for high resolution)