Infectious causes of chronic disease
tsmith | June 21, 2011As I mentioned yesterday, the epidemiology of hemolytic uremic syndrome (HUS) was murky for several decades after it was first defined in the literature in 1955. In the ensuing decades, HUS was associated with a number of infectious agents, leading to the general belief that it was a "multifactorial disease"--one that had components of genetics and environment, much like we think of multiple sclerosis today, for example.
Several HUS outbreaks made people think twice about that assumption, and look deeper into a potential infectious cause. A 1966 paper documented the first identified outbreak…
tsmith | June 20, 2011It appears that the E. coli O104 sproutbreak is starting to wind down, with more than 3,500 cases diagnosed to date and 39 deaths. Though sprouts remain the key source of the bacterium, a recent report also documents that human carriers helped to spread the organism (via H5N1 blog). In this case, it was a food service employee working at a catering company, who spread infection to at least 20 people before she even realized she was infected.
As with many infectious diseases, there are potential lingering sequelae of infection, which can occur weeks to years after the acute infection has…
tsmith | July 13, 2010Blogging from Atlanta at ICEID, the perfect venue to highlight today's story in the NY Times by Carl Zimmer discussing gut microbes in health and disease--including an introduction focusing on fecal transplants to treat Clostridium difficile infections. If you're at ICEID, be sure to swing by several posters in both sessions today showing new work (ours and others') on zoonotic MRSA.
tsmith | April 29, 2010Student guest post Dayna Groskreutz
Pulmonary hypertension (PH) refers to a condition in which there is high blood pressure in the vessels carrying blood from the heart to the lungs. Pulmonary arterial hypertension (PAH) is a subset of PH referring specifically to an increase in the pressure within the pulmonary arteries (rather than the pulmonary veins or capillaries). The high blood pressure in the vessels causes thickening of these arteries, making it hard for the heart to pump blood to the lungs. Pressure builds up and backs up. Over time, stress on the heart causes it to enlarge, and it…
tsmith | April 29, 2010Student guest post by Raj Nair.
Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease that affects the central nervous system (CNS) consisting of the brain and the spinal cord [1]. It is thought to be an autoimmune disease since individual's immune system attacks their own healthy tissues [1]. However, studies to ascertain triggering factors such as genetic, environmental, and infectious causes are still in progress [2]. So one wonders "Who is more susceptible to develop MS" Literature reveals that typically people between 20 and 50 years of age are commonly diagnosed…
tsmith | April 27, 2010Student guest post by Shylo Wardyn
"Of all the parasites I've had over the years, these worms are among the... hell, they are the best".
Was Fry from the animated show 'Futurama' right in his assessment of worms being good for him? Did he know something about parasitic worm infections that I was unaware of? Well, in the show, his parasites were doing remarkable things for his body, but does this translate to real life at all? Some people think so. Altman reviews the idea that over evolutionary time, our ancestors were infected with all sorts of parasites and this led to an interaction…
tsmith | April 27, 2010Student guest post by Desiré Christensen
Colorectal cancer (aka colon cancer) includes cancers of the colon, rectum, and appendix. Colorectal cancer is more common in developed countries (e.g. United States and Japan) compared to developing countries in Africa and Asia. Each year in the United States, there are around 150,000 cases of colorectal cancer diagnosed and about 50,000 people die from this cancer. Risk factors for colorectal cancer include lifestyle factors (e.g. habitual alcohol use; high-fat, low-fiber diet; obesity; sedentary lifestyle; smoking), family history of intestinal…
tsmith | April 26, 2010Student guest post by Andrew Behan
Malignant Mesothelioma (MM) is a rare type of cancer which manifests itself in the thin cells lining the human body's internal organs. There are three types of MM; pleural mesothelioma, peritoneal mesothelioma, and pericardial mesothelioma, affecting the lining of the lungs, abdominal cavity, and lining of the heart, respectively (1). Pleural mesothelioma is most common, consisting of about 70% of all MM cases and has a poor prognosis; patients live a median time of 18 months after diagnosis. (Note: for the purposes of this article, MM will be used to…
tsmith | April 26, 2010Student guest post by Jay Watson
Tired again? Perhaps it's the crappy weather, because you're sure that you've been getting enough sleep. After all, you can't remember the last time you spent less than ten hours in bed per night. Hopefully it's not mono; one of your friends had it a few months ago and it's all but knocked her out. However, you soon realize that you've only talked to her on the phone since she got engaged, so there's no way that's it. It's strange, even everyday activities like running errands has turned into something utterly exhausting. As you consider the reasons as…
tsmith | April 26, 2010Student guest post by Anne Dressler
Ninety percent of menstruating women experience some kind of premenstrual symptoms during the luteal phase of the menstrual cycle, with 20-30% experiencing moderate to severe symptoms. With an even more severe collection of symptoms, is premenstrual dysphoric disorder (PMDD). 3-8% of menstruating women report symptoms severe enough to be considered suffering from PMDD. Yet another designation, premenstrual magnification (PMM), is used to describe women who are symptomatic the entire cycle but have a premenstrual exacerbation of a diagnosed psychiatric,…
tsmith | April 23, 2010Student guest post by Zainab Khan
Schizophrenia has puzzled and often times scared not only the scientific community, but also the general public since its emergence. Cases of schizophrenia-like behavior have been well documented in history. As this disease has been studied, factors such as genetics, environment, and even personal habits have all been associated to some degree with schizophrenia. However, evidence in past years has mounted showing an association between infectious agents and schizophrenia. The three main infections associated/studied with schizophrenia have been…
tsmith | April 22, 2010Student guest post by Ron Bedford
The NYT (Kolata, 2010) recently published a story we'd all like to believe in. After their "lab's usual end-of-the-week beer hour," two Harvard neurology researchers noticed similarities between not only genes associated with both the innate immune system and Alzheimer's disease (AD), but structures, characteristics, and actions of selected proteins as well. Dr. Rudolph E. Tanzi, Dr. Robert D. Moir, and their team found "striking similarities" between the well-known innate immune system protein, LL-37, and amyloid β-protein (Aβ), long considered a waste…
tsmith | April 22, 2010Student guest post by Liz Stepniak
In the field of chronic disease, genetics has long been determined as a component of disease susceptibility. Infectious disease was believed to be caused by an agent of infection, such as a virus or bacteria which comprises a large environmental factor. In the past decade or so, this view has been expanded to include an important genetic factor as well.
There has been scientific evidence supporting the controversial idea that one error in a single gene can significantly alter the individual's risk of obtaining a bacterial infection. Can infectious…
tsmith | April 20, 2010Student guest post by D.F. Johnston
As the year marches forward, ever closer to that summer sun we missed so much during dreary winter days, we also get closer to the traditional summer picnics and barbecues. Sometimes, in our hurry to enjoy quality time with friends and family, we get distracted from our usual practices for proper food handling. We might try to get little Billy his hamburger before he has time for a full-fledged temper tantrum, so we hurry it along, figuring a tiny bit of pink in the middle won't be the end of the world. Or we might realize that we're short a couple of…
tsmith | April 20, 2010Student guest post by Laura Vonnahme
As a part of traveling to a developing nation, we are often required to take medical precautions. This generally includes a line-up of shots for various diseases, a few other tests, and various regimens of prophylaxis for possible diseases. I have often left these doctors appointments with a line of band-aids on my arm, a handful of prescriptions and a little weakness in my knees. However, I will readily admit that my malaria prophylaxis is often pushed to the back burner; in fact the last time I went to a developing nation, I didn't even get the malaria…
tsmith | April 19, 2010Student guest post by Ahn To
There are two separate philosophies regarding the relationship between life and food. There are those that believe we only eat to live. On the other hand, there are those that believe one of life's greatest pleasures is food. I am a firm believer of the latter, thus, you can imagine my horror when I first learned of celiac disease (CD). This is a disease with no treatment except for a lifetime on a gluten-free diet, thus people with CD cannot eat many types of food. I knew then that I had to find out more about causation of CD, which includes the complex…
tsmith | April 19, 2010Student guest post by Francis Mawanda.
HIV/AIDS is a major public health problem worldwide. To date, it is estimated that more than 60 million people have been infected with HIV and more than 25 million people have died as a result of HIV/AIDS worldwide1. Despite the high prevalence and mortality rates that are associated with HIV/AIDS, and after more than 29 years of aggressive research efforts, there is still no cure or vaccine to prevent against HIV/AIDS. And although the introduction of antiretroviral (ARV) drugs in the mid 1990s greatly improved the outlook, health and quality of life…
tsmith | February 26, 2010Student guest post by Shylo Wardyn
I recently read the book 'Good Germs, Bad Germs' by Jessica Snyder Sachs. I became intrigued by parts of her book that discussed how babies become colonized with bacteria during birth. The most interesting part was the differences between vaginally-delivered and Caesarean-delivered babies. It was not something I had ever thought of before. With my interest piqued, I did a Google scholar search to see what kind of research was being done on this topic. I stumbled upon an article looking at C-sections and risk of childhood allergies, namely asthma. I…
tsmith | February 25, 2010Student guest post by Desiré Christensen
Human papillomaviruses (HPVs) are small DNA viruses that infect epithelial cells. There are well over 100 subtypes of HPV. The subtypes that infect cutaneous epithelia are termed beta-HPVs and those that infect the mucosal epithelia are termed alpha-HPVs. Some alpha-HPVs have received attention as strong risk factors for the development of cervical cancer. Less public awareness has been generated over the role of HPVs in the development of other cancers such as vulvar, vaginal, anal, head and neck, and penile cancers. Only recent research has…
tsmith | February 25, 2010Student guest post by Andrew Behan
Type I Diabetes Mellitus (T1DM) is a disease most affecting children (previously named juvenile-onset diabetes). However, adults can still develop this life-threatening illness. Research in the genetic arena has provided evidence this disease is partially due to inheritance, leaving a portion of causality yet to be determined. More specifically, a look at certain viruses which attack the beta cells of the pancreas, the cells responsible for producing insulin, have provided new information regarding etiology of T1DM. Some recent research aimed at…