Thursday, August 21, 2014

Implications of the Continually Growing Accumulation of Microplastics in the World’s Oceans

In an article appearing in the journal Science, authored by Kara Lavender Law of the Department of Oceanography at Woods Hole, Massachusetts and Richard C. Thompson of the School of Marine Science and Engineering at Plymouth University UK, attention is drawn to microplastics in the world's oceans. 

Although the focus of the pollution of the marine environment with plastics is usually on the unsightly appearance of this detritus, there is now growing concern among the scientific community of the presence of so-called, “microplastics” – particles of plastic so small as to be essentially undetectable by the eye.  Microplastics have been used to describe particles smaller than 5 mm in diameter (where 5 mm = .197 inches).  This particular population of marine pollutants is ever-growing due to the ineluctable degradation of plastic pollutants to microplastic-sized particles. 

One of the chief environmentally-based concerns is focused on the fact that particles of this size are readily ingested by organisms as small as zooplankton – organisms that play a crucial role in the marine food chain. The sources for microplastics in the marine ecosystem are manifold including –
·         Degradation of larger items entering rivers through runoff, tides, wind and catastrophic events such as tsunamis, hurricanes and earthquakes
·         Cargo lost at sea and other debris originating from on board ocean vessels
·         Microplastic-size particles such as cosmetic beads and clothing fibers that on account of their size can readily pass through waste water treatment facilities.

Once in the oceans these particles are passively transported by many and diverse factors.  They are found ubiquitously in coastal sediments around the world and, as stated previously, are readily ingested by many types of marine organisms including mussels that can retain these particles long after ingestion.  The impact of the presence of these particles on the biology of the organisms that ingest them is not clearly understood.
One of the more disturbing properties of microplastics is their propensity to adsorb environmentally harmful chemicals such as dichlorodiphenyl-trichloromethane (DDT) and polychlorinated biphenyls (PCBs) on their surface and consequently passively concentrate these dangerous substances.

Although the real risk of the presence of microplastics upon the health of the marine ecosystem is exceedingly difficult to ascertain, it is certainly worthy of further study.

Wednesday, August 6, 2014

A Possible Relationship Between Preeclampsia and Proteins

Approximately 5% to 10% of pregnant women worldwide suffer from preeclampsia.   This is a condition in which there is a sudden and precipitous rise in the pregnant woman’s blood pressure.   In many cases, if the baby isn’t delivered immediately, the mother may die, for the full-blown development of eclampsia can lead to seizures and severe hemorrhaging.  This is especially problematic In low-resource countries that do not have access to the sophisticated equipment required to sustain the life of premature infants.  In fact, the death toll from this condition worldwide is estimated to be 76,000.

The etiology of this disease remains an enigma.  Some of the suggested causes include abnormalities in the immune system’s tolerance of the presence of the fetus, abnormalities in the development of the placenta or dietary factors. 

In spite of the apparent mysterious nature of this syndrome, there is a revealing aspect to its presentation.  It has recently been shown that preeclampsia is marked by the appearance of misfolded and clumped proteins.  Interestingly, among the proteins implicated is amyloid precursor protein – the same protein that is implicated in Alzheimer’s disease.   There is to date not enough evidence to unambiguously describe preeclampsia as a “misfolding” disease - It is also possible that the presence of misfolded proteins is a symptom rather than the cause.

Taking these data into account, Dr. Irina Buhimschi, an investigator from Nationwide Children’s Hospital and Ohio State University, decided to look for a diagnostic tool that would be a better predictor for this condition in pregnant women.   In a study involving 600 pregnant women, urine samples were taken and subsequently analyzed for the presence of misfolded proteins.   From this study, a simple test was devised using the dye Congo Red.  It was found that Congo Red binds to clumped and misfolded proteins producing a distinctive red color.  It was shown that this test has an accuracy of 80% or higher in indicating the presence of preeclampsia.

This is a very important discovery especially in regards to its worldwide application, for it is a very inexpensive and simple procedure that has the potential to save countless lives especially in low-resource environments.