Feb. 27th Chilean Earthquake no shock to geophysicists

By Marci Wills, March 6, 2010

A building damaged in Conception, Chile by the February 27th, 2010 earthquake

The enormous magnitude 8.7 earthquake which struck Chile last Saturday (February 27th) in startling proximity to the Haiti disaster has lead some of my friends and family to an apocalyptic level of speculation. They want to know what freak force of nature caused these earthquakes to occur so close together? But it is important to remember that earthquakes are a normal occurrence on Earth that can happen at any time. In fact, last week’s upheaval in Chile came as no surprise to the scientific community and to two geophysicists in particular who expected it to happen.

Jian Lin of the Woods Hole Oceanographic Institute (Woods Hole, MA) and Ross Stein of the United States Geological Survey (Menlo Park, CA), had anticipated an earthquake in the location of the Feb 27th event since the completion of their research in the region 6 years ago. In a paper published in the Journal of Geophysical Research in February of 2004, they warned that this area was at increased risk of a large earthquake due to after effects of the world’s largest recorded quake, a magnitude 9.5 event, which occurred in Chile in 1960.

Both the 1960 and 2010 Chilean earthquakes occurred just off the west coast of Chile along a tectonic plate boundary where the Nazca plate moves beneath the South American plate. Stress accumulates along this boundary until it is suddenly released by movement of the plates during an earthquake. The portion of the plate boundary that moves, called the earthquake’s rupture zone, can stretch hundreds of kilometers. Stress is relieved in this zone following an earthquake but it may increase elsewhere.

Jian Lin and Ross Stein used GPS measurements of tectonic plate motion to estimate changes in stress from the 1960 event and found that stress had greatly increased just north of the 1960 rupture. They predicted that this region would be the next portion of the plate boundary to produce a large earthquake in Chile. Sure enough, last Saturday  the 2010 earthquake picked up where the 1960 earthquake rupture left off.

This sort of progression also occurred after the December 26th, 2004 magnitude 9.0 earthquake in Sumatra, when it was followed by a magnitude 8.7 earthquake on the southern end of the rupture zone just 3 months later on March 28, 2005. “The only difference is that it took 50 years for the northern neighboring section of the 1960 [Chile] earthquake to rupture, while it took only 3 months for the southern adjacent segment to rupture in Sumatra”, Lin noted.

Lin believes that the Haiti earthquake similarly transferred stress further east along the Enriquillo Fault which broke on Jan. 12th, but it would have had no effect on the stress state in Chile.

Lin and Stein also used their method of measuring stress changes to assess which faults in the San Andreas region of southern California are most likely to move next, but only time will reveal the accuracy of their predictions there. It seems as though we are another step closer to understanding and anticipating earthquakes, rather than thinking of them as freak events.

Sources:

Lin, J, and Stein, R.S., 2004, Stress triggering in thrust and subduction earthquakes and stressinteraction between the southern San Andreas and nearby thrust and strike-slip faults: Journal of Geophysical Research, v. 109.

http://www.whoi.edu/page.do?pid=7545&tid=282&cid=69866&ct=162

Discoveries in Diabetes, Depression, and Dementia

By Shelly Hwang

Diabetes, Depression, and Dementia are three of the most common medical conditions among Americans today. A recent study released on March 5 by a group of researchers at the University of Washington (UW) revealed that depression in diabetic patients doubles the risk of developing dementia, a finding that may affect the way that depression is screened and treated in order to prevent the development of other diseases.

Dementia is the gradual loss of cognitive and reasoning abilities, including memory loss, wandering, inability to do basic math, and forgetting familiar things or people.  Depression is a mental disorder marked by low mood and poor concentration. Diabetes is a medical condition in which a person has a high blood sugar level. While both diabetes and major depression have been shown to be separate risk factors for dementia, the effect of both diabetes and depression on dementia has not been studied. It turns out that adults with both conditions are twice as likely to develop dementia, compared with adults with only diabetes.

This project, led by Dr. Wayne Katon, a professor of psychiatry and behavior sciences at UW, is a part of the Pathways Epidemiological Follow-Up study, which examines adults from the Group Health Cooperative’s diabetes registry. Patients from nine clinics in western Washington State were studied for five years. 163 of 3,382 (4.8%) patients with diabetes alone developed dementia, while 36 of 455 (7.9%) of the diabetes patients with major depression were diagnosed with dementia. This presents a 2.7 fold increase of dementia in diabetic patients with depression.

Depression is common among individuals with diabetes. Previous studies found depression increases mortality rate among diabetes patients, in addition to health complications. However, the way the two diseases interact is unknown. Perhaps they interact by genetics, increasing stress levels, or resulting in unhealthy behaviors such as smoking, lack of exercise, and over-eating, which raise the risk of dementia. Diabetes is a known risk factor for dementia because it causes blood vessel problems, tissue damage, and increased blood sugar levels, which all increase odds of developing dementia. Although the link between depression, diabetes, and dementia is still not understood, it is useful for doctors to screen and treat for depression as a preventive measure against the development of cognitive deficits or dementia in diabetic patients.

Original Press Release

VA Puget Sound Health Care System Clinical Research Unit

Info on Dementia

TB or not TB?

Justin Williams ’13

Ever since doctor Robert Koch discovered the bacteria responsible for tuberculous, there has been many hours poured into researching everything about the disease. Through the years, researchers have unearthed almost everything, but one area that is notably lacking is determining any kinds or risk factors. However, on March 4, 2010, researchers at the University of Washington have discovered a gene that may be a major determining factor in susceptibility to TB.

Researchers conducted experiments on zebrafish, in which the severity of the TB could be easily identified due to their clear bodies. The scientists genetically altered the genetic makeup of the zebrafish before injecting them with the tuberculous bacteria and then observing the severity of their TB symptoms.

X-ray of a person with tuberculous.

Their experimentation and subsequent results turned out to be very interesting. They found that the lta4h gene, and it’s genotype (what two particular copies of it you have) are very important in determining how susceptible a person is to contracting TB.

For those of you who are not familiar with genetics, the majority of genes come in two differentforms. You get one copy from each of your  parents. It is possible to get both of one kind, one of each, or one of  the other kind. In this particular lta4h gene, the two different types  are inflammatory and anti-inflammatory. Researchers found that  when zebrafish have one copy of each of the genes, their response to  TB is much better than if they only have copies of one or the other  (i.e. the response of zebrafish with one inflammatory and one anti-inflammatory copy was much better than those who had two copies of the inflammatory or two copies of the anti-inflammatory).

Comic illustration of the lta4h gene.

While this research was conducted on zebrafish, the scientists did look into the structure of the gene in humans to determine its relevance. Their investigations proved fruitful and the implications of this for humans are promising.Also, their newfound knowledge that an over inflammatory response can be hurtful for the fight against TB provides some hope “that corticosteroids and other anti-inflammatory agents can be useful as adjuvants in some cases of TB where antibiotics alone are failing.” Whichever way you look at it, the results are exciting and promising for people involved with tuberculous.

Sources:

http://www.eurekalert.org/pub_releases/2010-03/uow-rdg030210.php

http://nobelprize.org/educational_games/medicine/tuberculosis/readmore.html


The Gift of Sight: Treating Blindness with Gene Therapy

By Johnathan Nieves

Findings from a new study show that gene therapy may be effective in treating a rare disease that progresses to total blindness by adulthood.

 

Imagine how difficult daily activities would be without being able to see. For 1.3 million Americans today, that is the reality they face.  For a subset of individuals, though, gene therapy may be the answer to curing their debilitating disease. Findings from a study published March 3rd in Science Translational Medicine showed that gene therapy may be effective in treating Leber’s congenital amaurosis (LCA), a rare genetic disease that progresses to total blindness by adulthood.

Gene therapy for LCA, which produced dramatic improvements last year in 12 children and young adults who received the treatment in a clinical trial, has cleared another hurdle.  In the human trial for LCA reported last year, researchers at PENN Medicine and The Children’s Hospital of Philadelphia treated only one eye in each of their 12 patients. Because the treatment was experimental, researchers left one eye untreated in the event of unexpected complications. After the patients experienced partially restored eyesight in their treated eyes, many were eager to receive the same treatment in the other eye.

The same research team that conducted the human trial now reports that a study in animals has shown that a second injection of genes into the opposite, previously untreated eye is safe and effective. The study suggests that patients with LCA who benefited from gene therapy in one eye may experience similar benefits from treatment in the other eye.

“We designed this study to investigate the immunological consequences of administering the

Source: U.S. National Library of Medicine

gene therapy injection to the second eye after treating the first one,” said corresponding author Jean Bennett, M.D., Ph.D., F.M. Kirby professor of Ophthalmology at the University of Pennsylvania School of Medicine. “The good news is that in animals, the second injection, like the first, is benign.”

 As in the human trials of this gene therapy, the researchers packaged a normal version of the missing gene that causes LCA into a vector. The vector, a viral messenger that is used to incorporate a gene into a cell’s DNA, was used to deliver the gene therapy to cells of the retina, the light sensing region of the eye. Once in the retina cells, the vector is able to incorporate the gene into the cell’s DNA. Once incorporated into the DNA, the cell’s DNA reading machinery can translate the gene and produce an enzyme that restores retinal function, effectively reversing blindness (to view an animation of this processess click on the image above).

 Although the virus used in the study does not cause human disease, it previously set off an immune response that cut short the initial benefits of gene therapy. In the current study, the team found no evidence of toxic side effects in the 10 animals that received treatment. All the animals, which had been specially bred to have inherited blindness, had improved vision, and showed no toxic effects from the treatment.

The study “provides encouraging indications that immune responses will not interfere with human gene therapy in both eyes,” said co-author Katherine A. High, M.D.  Additionally, the results may set the stage for gene therapy in LCA patients who were excluded from the previous trial. At present, the research team is planning another clinical trial of LCA gene therapy, which may include some of the patients from the first human trial.

 To view the original press release pertaining to this article, click here.

Biodiesel improves health in school buses AND students

By Amy Woolf

School buses in one school district in Michigan have been running on B20 (20% biodiesel) since 2002, and since that time, the bus maintenance team has noticed a major improvement in the health of the buses’ moving parts. Recently a St. John’s district school bus completed its 300,000th mile, a feat never before achieved in a Michigan school district.

Engines that are fueled by biodiesel are able to go longer between oil changes. The mechanics in St. John have been able to go from changing the oil every 6,000 miles to 12,000-18,000 miles. This saves the school district money on oil and filters. These savings are due to the biodiesel lubricating the moving parts in an engine better than average diesel fuel.

Using biodiesel not only improves the health of the school buses, the students and the drivers of the buses also stand to benefit from vehicles running on biodiesel. Using biodiesel has been proven to have fewer harmful emissions than regular diesel. Its health benefits have been recorded from its use in mines across the United States, miners’ respiratory health has improved with the use of biodiesel.  In fact, school districts using biodiesel have reported fewer students complaining of headaches and fewer missed school days. Students that are riding in a school bus running average diesel are exposed to exhaust levels that are higher than the level considered to pose a cancer risk. The diesel exhaust levels recorded inside a running school bus are 23 – 46 times higher then the level identified to pose a cancer risk.

Overall using biodiesel in school buses has a positive environmental impact, a positive health impact, and a positive financial impact. It stands to reason that more school systems should consider the switch to biodiesel.

Press Release

Fluorescent supermarket lighting leaves spinach more nutritious than ever

Spinach on display under 24-hour light in supermarkets actually gains in content of some nutrients. (Marc Villalobos, USDA-ARS)

by Allison Younkins

Healthier spinach, just add light

Spinach, or Spinacia oleracea, is one of the most nutritious vegetables found in the grocery store.  Normally packaged in a clear plastic container, most spinach leaves are exposed to fluorescent supermarket lights for up to 24 hours a day.  Surprisingly, a study published in March in the Journal of Agricultural and Food Chemistry shows that the light exposure boosts the vegetable’s nutritional content to astonishing levels.  Scientists at the Kika de la Garza Subtropical Agricultural Research Center and the Atlantic Food and Horticulture Research Centre conducted an experiment to test the affect of lighting on the nutritional value of spinach.  They exposed spinach to either continuous light or darkness while under simulated supermarket storage conditions for up to 9 days.  Even spinach leaves exposed to the fluorescent lighting for only three days showed significant increases in important vitamins and antioxidants.  The leaves exposed to nine days of light had increased folate levels by 84-100% and levels of vitamin K between 50-100%.  Even further, the group exposed to no light had declining nutritional values.

How light contributes to nutrition: the connection

The main researcher on this project, Gene Lester of the USDA Agricultural Research Service, explains how supermarket lighting can contribute to vitamin and mineral levels within the leaves of this powerhouse plant.  Lester clarifies that although a leaf has been detached from the original plant, it can still undergo the process of photosynthesis.  The lighting in supermarkets allows the spinach leaves to continue creating vitamins and minerals as they would naturally.  Lester comments, “As long as there is moisture in the leaves and as long as there is gas exchange and light, it is good to go whether they are picked or not.”

How other vegetables and consumers can benefit from this study

The most exciting implication of these results is that other vegetables may receive the same benefits from fluorescent lighting.  Keeping vegetables fresh in grocery stores is a constant struggle, and additional studies may illuminate more effective storage solutions.  One serving of spinach currently provides 20% of your daily recommendation for vitamins C, A, B9, K, and E but with further research soon you may be getting more bang for your nutritional buck!

Want to learn more? Check out the resources I used for this blog:

Supermarket lighting enhances nutrient level of fresh spinach

Want fresh veggies? Let there be light!

The Sea Squirt: An Answer to Alzheimer’s?

Ciona intestinalis

By Kelly Lohr

The newest breakthrough in Alzheimer’s research is coming from an unlikely source–a sea squirt.  Just this week (March 2, 2010) Mike Virata and Bob Zeller of San Diego State University believe that Ciona intestinalis, known commonly as the sea squirt, may be the perfect model organism for this disease.

The brains of Alzheimer’s patients are typically filled with tangles and plaques made of the protein fragment beta-amyloid.  Alzheimer’s disease affects nearly 4 million Americans and an estimated 27 million people worldwide. It is the most common form of age-related dementia and has no cure. Current drug regimens only relieve symptoms and cannot halt the progression of the disease. Research in the scientific community is currently  aimed at slowing the disease through drugs such as Aricept and Namenda which are focused on decreasing plaque accumulation.

Recently, research has shown the need for an improved model organism to aid  in understanding the pathology of the disease.  Currently, genetically modified strains of mice have been the organism of choice in the research of this disease. However, there are limitations in the use of mice including an extremely long waiting period for plaque development like those seen in Alzheimer’s brains. Also, these mice do not contain the same genetic mutations linked to hereditary risk of Alzheimer’s disease.  Mice are also more costly to purchase and maintain for research.

Sea squirts are tunicates, marine organisms with a hard outer tunic and a soft body. They live on underwater structures and are filter feeders that eat small plant material. It has been suggested that sea squirts are actually our closest invertebrate relatives.  As far as research benefits, sea squirts share nearly 80% of our genes and resemble vertebrates in their immature form.  These animals are inexpensive to house and contain all of the genes needed for the development of Alzheimer’s plaques in humans.

An immature sea squirt.

Virata and Zeller found that by giving the immature sea squirt amyloid precursor protein, a mutant protein linked to hereditary Alzheimer’s, sea squirts developed brain plaques in a single day.  Further, these plaques and the behavioral deficits seen in these animals were able to be reversed using a drug meant to remove plaques.  Such techniques have been ineffective in all other invertebrate models, including the commonly used nematode, C. elegans.  Now, investigators can be freed from genetic, time, and financial constraints.  These findings provide a resource for an entirely new take on Alzheimer’s research…all because of a sea squirt.

For more information, click here.

Hope for mixed-lineage leukemia’s hopeless prognosis

By Sara Braniecki

A team of researchers at University of Pennsylvania School of Medicine led by Xianxin Hua, MD, PhD, have gained detailed understanding of how mixed-lineage leukemia (MLL) fuels itself to continually cause blood cells to grow out of control.  The information, which the researchers published in he current (Feb 2010) issue of Cancer Cell, is imperative in the researchers pursuit to find an effective treatment for MLL patients in the near future.

“This research not only uncovers the crucial role of a normal protein key to the development of MLL, but also how the cancer cells stay alive in the first place,” says Hua.

MLL is an aggressive childhood cancer that occurs when a piece of chromosome 11 breaks off and attaches to a different chromosome, resulting in uncontrollable blood cell growth.  Children diagnosed with MLL poorly respond to common leukemia treatments, leaving little hope for these children.

When the piece from chromosome 11 attaches to a different chromosome, a protein is produced that leads to the uncontrollable blood cell growth that makes the children so ill.  The researchers call this protein the “fusion protein.”  The researchers deleted the gene for the normal protein from leukemia cells and the uncontrollable growth of cells did not occur, which led them to their conclusion that this normal protein was necessary for MLL to thrive.

Knockdown of normal MLL gene in human leukemia cells reduces leukemic infiltration in mouse bone marrow (left), compared with heavy leukemic infiltration in marrow from leukemia cells with normal MLL gene (right). Arrows denote leukemic cells.

Another crucial conclusion for their research is that the normal MLL protein and the “fusion proteins” interact due to chemical modifications on chromosomes.  These modifications allow a change to occur that increases the number of leukemia cells that survive over time and keeps a sufficient amount of leukemia stem cells present.

As Hua’s team of researchers continues to gain understanding of MLL they will hopefully find a better treatment for the patients afflicted with the disease.  Being diagnosed with a disease with such little hope for treatment and control is perhaps one of the most disheartening things that can happen to a child.  Hua’s team is on the right track to finding the treatment needed to give hope to children with MLL.

Further information.

Tainted Blood

By: Nina Jean-Jacques

Over the last decade, the incidence of blood poisoning has dramatically increased. Blood poisoning, or sepsis, may sound like a bioterrorist attack, but it happens in the human body during a response to infection. Researchers at the Carolinas Medical Center in Charlotte, N.C. found that the use of lactate detection is highly effective in identifying proper blood flow. Early detection and treatment of the diseases is critical because it is an extremely life threatening condition.

The previously recommended system to evaluate blood flow and oxygen delivery to the different parts of the body was to test how saturated the blood was with oxygen. The Carolinas Medical Center study found that monitoring the amount lactate removed from the blood is a more accurate way of detecting sepsis. In a study comparing the different methods, more patients died when using the oxygen method. All patients in the study underwent the same treatment therapy and showed no difference in the levels of side effects.

To measure the oxygen levels, a catheter must be placed in the chest to test the central venous blood. Testing lactate concentration is less invasive in that regard where the catheter is not needed. Keeping patients as comfortable as possible is an essential part of treatment. The efforts to improve observation of sepsis are a giant step in the right direction.

Source

Bird flu: A Thing of the Past?

By Nick Gubitosi

This past Friday (February 26, 2010) a group of scientists led by a virologist from the University of Wisconsin published a study about a new antiviral, which was found to be highly effective against the pathogenic H5N1 avian influenza virus.  What stands out about this new antiviral, known as CS-8958, is that it has been proven to be effective against Tamiflu resistant strains of H5N1. This makes it a promising candidate for the future treatment and prevention of the bird flu.

Antiviral drugs are used in the treatment of viral infections by inhibiting the development of disease causing pathogens, and are a vital component in the countermeasure against human influenza viruses.  Recently many new strains have been emerging, which show resistance to Tamiflu, an antiviral that slows the spread of the influenza virus within the body.  These resistant strains pose a threat and make the development of new antivirals a pressing issue.

Professor Yoshihiro Kawaoka from the University of Wisconsin and his team of scientists tested a drug created from a novel neuraminidase inhibitor on mice in order to see its effectiveness against H5N1 strains of influenza.  Neuraminidase inhibitors are a class of antiviral drugs that specifically target the influenza virus by blocking one of its proteins, therefore preventing its replication within the body.

They began their tests by giving a single dose of the CS-8958 antiviral drug nasally to mice, two hours after infection with the H5N1 influenza virus.  The results showed that the survival rates were higher in the mice given this new drug when compared to mice given a standard five day treatment with Tamiflu.  In another experiment, CS-8958 was found to be effective against highly pathogenic and Tamiflu resistant strains of H5N1, while it was also shown to protect mice against lethal H5N1 infection when it was administered seven days before infection with the virus.

With the information gained from this study, future treatment and prevention of H5N1 with this CS-8958 antiviral could be the most effective treatment to date due to its ability to eliminate newly emerging drug resistant strains in only one dose.  While future studies still need to be conducted to make sure that these results are the same when tested on humans, the potential of this new antiviral is promising and could possibly put an end to the fear of the bird flu pandemic.

Click here for source