An understanding of science in this the 21st century is an essential ingredient for leading a productive and rewarding life.
Friday, July 29, 2011
The Waste of Human Potential
Wednesday, July 27, 2011
An Entirely New Breed of Bacteria
Tuesday, July 12, 2011
New Hope for Those Suffering from Type 1 Diabetes
Unlike adult-onset diabetes, type 1 diabetes occurs early in life and is considered to be an autoimmune disease where the body's own immune system becomes mobilized against the insulin-producing cells that reside in the Islets of Langerhans in the pancreas. This is an extremely devastating illness, since the resulting dramatic loss of insulin results in high levels of glucose in the blood – a condition known as hyperglycemia. Although insulin treatments can control this condition, excess glucose circulating in the blood system reacts with tissues throughout the body and leads to devastating side effects over time including blindness, kidney dysfunction, heart disease and the enhanced likelihood of amputations on account of poor circulation.
There is, however, encouraging news on the horizon. Results from a clinical trial conducted by Doctor Denise Faustman and her colleagues from the Immunology Laboratory at Massachusetts General Hospital indicate that a medication, bacillus Calmette-Guerin (BCG) used routinely as part of the treatment regimen for bladder cancer and as vaccination against tuberculosis could significantly improve the treatment for type 1 diabetes. BCG is produced from a strain of the weakened live bovine tuberculosis bacillus.
Thursday, June 30, 2011
Climate Change Mirrors an Earlier Era in Planetary History
- Marked increase in global temperatures (as noted above)
- Climate zones shifted towards the poles both on land and in the ocean propelling the migration of living things to accommodate this change
- Within the ocean depths, acidity increased and the supply of oxygen diminished killing of many organisms there.
Friday, June 17, 2011
Antibiotic Resistance – A Cause for Global Concern
Penicillin was discovered and developed as the first widely-used anti-microbial (antibiotic) agent in 1928. Ever since that time, bacteria have developed resistance to a wide range of antibiotics as they have been introduced. This capability can be explained based on two important properties of bacteria. These organisms divide approximately every twenty minutes; therefore, through the course of a single twenty-four hour day, seventy-two generations have been produced. If bacteria are in an environment permeated with antibiotic some of the progeny may develop a resistance due to a spontaneous mutation in their genetic material (DNA). If this should happen, all the susceptible bacteria will die off leaving behind those that are resistant. This process can be regarded as natural selection. Since resistance is conferred by a change in the genetic makeup of the organism, resistance can then be passed on to all the progeny. There has always been a potential public health risk in regard to this ability of microorganisms to become resistant to these agents.
Bacteria are classified into two distinct groups – gram-negative and gram-positive. This classification was created based on their ability or inability to take up a particular stain. A well known example of gram-positive bacteria that is disease producing (pathogenic) is Staphylococcus aureus that is of a particular concern in a hospital setting. An antibiotic that has been traditionally used to combat this kind of infection is methicillin. As a result of its universal application, a highly resistance form of this bacteria referred to as methicillin resistant Staphylococcus aureus (MRSA) has arisen. This has created a serious public health dilemma.
From a public health perspective, a far more problematic issue is antibiotic resistance among gram-negative bacteria. These bacteria possess a double cell wall that makes them more challenging to eliminate. An example of a pernicious variety of this kind of bacteria is Klebsiella pneumoniae; this strain is particularly prevalent in hospitalized patients and is a major cause of pneumonia and bloodstream infections (sepsis). The antibiotics that have been found to be effective against gram-negative bacteria are referred to as the carbapenems. As one would suspect, Klebsiella has now been shown to possess resistant to the action of carbapenems.
Doctor Timothy Walsh and his colleagues from the Cardiff University, United Kingdom have examined the nature of this resistance and have found that the resistant strain produces an enzyme (NDM-1) that effectively inactivates carbapenems. This is particularly disturbing since gram negative bacteria, Klebsiella as an example, also possess the capacity to transfer antibiotic resistance to other kinds of bacteria including the ubiquitous Escherichia coli that normally inhabits the large intestines of most mammals.
Given the seriousness of this issue, it is considerably disturbing that there are no new kinds of antibiotics against gram-negative bacteria currently being developed. This reality holds an ominous prospect for the future in regards to global public health.
Tuesday, June 7, 2011
Rheumatoid Arthritis – A Possible New Therapy
Rheumatoid arthritis (RA) is a chronic and debilitating illness. It can strike at any age and seems to be more prevalent in women than men. Although the specific etiology (cause) of RA is unknown it is categorized as an auto-immune disease – the body's immune system seems to mistakenly recognize normal tissue as foreign and attack it. Other examples of autoimmune diseases are multiple sclerosis (MS) and Systemic lupus erythematosus (lupus).
The target for the autoimmune reaction in RA is primarily the joints on both sides of the body -wrists, fingers, knees, feet, etc. The extent of the resulting disability can vary widely depending on other factors related to health.
In order to effectively treat RA, the underlying mechanism that leads to the disease needs to be better understood. Recent evidence has implicated the so-called tumor necrosis factor α (TNFα) as a major component in the development of this illness. TNFα is found on the cell surface of immune cells. TNFα is a member of a group of substances referred to as cytokines. Cytokines are small protein molecules that are secreted by both the nervous and immune systems. They have been found to play critical roles in the modulation of the immune system.
Dr. Hao Wu and his colleagues from the Department of Biochemistry at the Weill Cornell Medical College in New York City have shown the disease-producing role of this substance using mouse models of inflammatory arthritis. Furthermore, this investigative group has demonstrated that Progranulin (PGRN) slows the progression of arthritis in the mouse. Progranulin is a naturally occurring growth factor for human fibroblasts – cells responsible for the production of collagen, an integral component of the body's connective tissue. Progranulin seems to exert this inhibitory effect by binding to the receptor that normally binds TNFα, thereby inhibiting its role in the autoimmune process that results in RA.
These findings shed significant light on the immune process. These data may ultimately contribute towards the treatment of this intractable disease.
Tuesday, May 24, 2011
Global Changes in Wind Speed and Wind Height
The changes precipitated by the accumulation of greenhouse gases within the global environment are not limited to change in temperature, but are, in fact, many and diverse. The overarching range of effects that are a direct result of increased concentrations of greenhouse gases is referred to as climate change. It appears that certain changes in the world's oceans are directly related to climate change. We have already examined some of these influences including the rise in temperature and the increasing acidity of the world's oceans.
In a recent report from the laboratory of Dr. I.R. Young and his colleagues from the Swinburne University of Technology at Melbourne, Victoria, Australia, it has been established that there is a trend towards increases in oceanic wind speed and wave height. These findings are based on satellite-derived data using a variety of measuring devices including altimeters, sophisticated radar equipment, etc. The advantage of using this type of instrumentation is that the scope of investigation is global in scale.
Oceanic wind speed and wave height are involved in the maintenance of the flow of energy from the atmosphere to the ocean and are involved in upper-ocean mixing. In the analysis of the data, Young and his associates used a database that contained information collected over a twenty-three year interim. The authors of this study caution that on account of the relatively brief interval of time encompassed by these data, they cannot determine if this trend will continue to increase or accelerate into the future.
On account of the importance of these changes in terms of their possible impact on the global climate system, it would be judicious to extend the lifetime of this kind of study into the future.