Careful What You Put In Your Mouth!

Eating May Be Hazardous to Your Health: No Matter How Many Feet You Have!

Contaminated food items shipped from China to the US and destined for use in pet food, have been blamed for the death of dozens of cats and dogs. While the ‘official’ death toll is below 100 with many thousands of animals listed as ‘sickened’, the actual mortality rate may in fact be quite higher. The FDA admits to receiving over 16,000 calls re: sick animals [1] http://www.bloomberg.com/apps/news?pid=20601103&sid=aAyK9T1SNiYc
and many pets that died in the period immediately preceding the recall may have expired from organ system failure resulting from unspecified causes. Eventually, veterinarians began to recognize great similarity in emergency case presentations at the clinical level, specifically, renal compromise and liver malfunction caused by ingestion of toxic ingredients. Since most pet food manufacturers blend ingredients into batches as needed, the phenomenon did not become totally visible until a clear pattern of sickness emerged across the board over several months.

While some animals experienced a slow onset of symptoms and discomfort was not immediately evident, other pets collapsed with acute problems; all required emergency intervention and supportive care. IV fluids, electrolyte monitoring, intensive hepatic and kidney function monitoring and blood level analysis was necessary to achieve stability and support care in the recovery phase lasted as long as three weeks, depending upon the food ingested and the size of the patient.

What did this? Well, that answer depends on whether or not you believe the FDA. The FDA investigation into this matter has determined that ‘melamine’ a chemical used routinely in fertilizer in Asia, may have been intentionally added to the ingredients used to make pet food because it cause the protein analysis ratings to appear much higher than they actually are. [2] http://www.reuters.com/article/topNews/idUSWEN594320070330?feedType=RSS

Taken at face value, the plausible basis for this is that in the name of greed, someone in the pet food chain decided to cut corners in order to make an even bigger buck. End of story? Well, maybe not exactly.At the time of the FDA’s announcement, Cornell University Lab researchers had already identified ‘aminopterin’ a rodenticide that is illegal in the US, as being present in the pet food samples tested. [3]
http://www.news.cornell.edu/stories/March07/PetFoodUpdate.kr.html

The FDA declined to comment on that finding. It is one thing to spin a tale that attributes the presence of a toxic ingredient such as ‘melamine’ to a mistake by an Asian exporter trying to extend a profit margin, but it is a different matter entirely to explain the deliberate addition of a known poison. Such an act implies intent to do harm. A lethal chemical used to kill rats made it through the safety net the US government is supposed to enforce to insure the integrity of the food supply. From that perspective, this story isn’t completely about pet food, is it?

The vastness of the potential human threat posed by this situation is chilling. While meat and fish are inspected in great detail and fruits and vegetables are subject to irradiation and washing, ingredients…the fine print on the food label are virtually pushed through with barely a nod. "You don't have to be a Ph.D. to figure out that ... if someone were to put some type of a toxic chemical into a product that's trusted, that could do a lot of damage before it's detected," said Michael Doyle, a microbiologist who directs the University of Georgia's Center for Food Safety. [4] http://www.kiplinger.com/apnews/XmlStoryResult.php?storyid=350248

If the pet food poisoning was just a dry run to highlight the vulnerability of our import safety system and to scare Americans, I’d say it was quite successful.

CatherineS
Course Participant

Cinnamon--A Spice or a Pill?

Could cinnamon, the common household spice, used to flavor our cakes and cookies, have important medicinal properties that can be used help diabetes patients? Well, a recent article by Janet Raloff on the Science Magazine webpage www.sciencenews.org/articles/20070414/food.asp synopsizes a study on 56 teens with juvenile diabetes undergoing a 3 month trial at the Dartmouth-Hitchcock Medical Center in New Hampshire. The results imply that there is no evident effect. It previous studies, evidence suggests that a daily dose of a teaspoon of cinnamon benefits people suffering from type II diabetes. However, this study indicates that Type I (juvenile) diabetes is a different matter altogether. Cinnamon does not show any medicinal effect!

A 90-day trial was made on teens between 13 and 19 years of age afflicted with Type I diabetes testing the effect of a cinnamon pill. To see, whether the spice had medicinal value, half of the volunteers were given a lactose placebo and the other half a cinnamon pill containing 1 gram of the spice. Neither the doctors administering the pills nor the adolescents could tell whether the pill was the placebo or cinnamon. Such concealed placebo/pill trials are done to make sure that there are no psychological effects on the bodies’ physiological processes.

Type I diabetes is an autoimmune disease and unlike type II diabetes (which commonly spurs from obesity and aging) type I diabetes is a result of the immune system’s inability to recognize the body’s insulin-secreting beta cells as native to the body. The immune system attacks and destroys these cells and causes a rampant decrease in insulin hormone in the blood. Hence, in order to stabilize the level of blood sugar, daily injections of insulin are administered.

The study reveals that the measure of hemoglobin AIC, the proportion of red blood cells with bound glucose, increases rather than decreases in teens treated with either pill. Surprisingly, the AIC level was higher after the clinical trial than before the trial, rising from an average of 8.40 to 8.75 thus indicating an increase in blood sugar.

Perhaps the amount of cinnamon in the tablet is at a too low concentration to have any effect on boosting insulin production in type I diabetes. Or, contrary to popular belief, cinnamon may be detrimental to insulin production causing a rise in the level of glucose. However, we cannot decide whether cinnamon has any effect, on the whole, as the placebo also causes an increase in AIC values. It may be due to some other common factor. Personally, I think that the study can be done to yield more conclusive results if the trial period is lengthened to six or nine months using several different types of placebos. But don’t be surprised to learn that cinnamon still proves itself to be the best ingredient in cakes and apple pie!

-timoteo

Sports Drinks Bad For Our Teeth!

One can live with food for more two or three weeks, but no longer than a few days without water. We all need water on a daily bases, especially when involved in different sports activities. I remember learning in my human and anatomy class about a very complex region of our brain known as the hypothalamus. The hypothalamus can be thought as a thermostat or an auto control center that along with many other vital functions that it performs, it keeps our body’s temperature and fluidity in control maintaining homeostasis. The hypothalamus is also a thirst center and makes sure that we can get the fluid necessary for our body in order to balance the osmotic flow and stay hydrated. In the past, studies have proved that drinking water with electrolytes helps to hydrate oneself faster than pure water. Therefore, many beverage companies took advantage of this fact and made sports drinks that contain electrolytes. Today such drinks can be found in every store, and it is not considered to be detrimental to anything in our body.

A few years ago, a group of scientists from the dental field focused their studies on the electrolytes present in “sports” drinks. They tried to disprove the public’s positive opinion on these sweetened drinks by showing evidence of enamel erosion when the drinks are consumed. The scientists assembled a test group of individuals with healthy enamel and selected five popular sports beverages to study the negative impact, if any, sports drinks had on teeth. The recorded results, that included pH, time, amount, and other important data, clearly evidenced a large variation in dental health between the individuals that consumed water and individuals that consumed sports drink. Those participants that consumed the sweetened sports ‘ade’ drinks showed a high levels of enamel erosion, while the individuals that consumed only water, showed almost none.

The researchers proved their point by demonstrating the negative effects of the electrolytes and sugar in sports drinks on tooth enamel. The question remains, regardless of the level of activity, what should a really dehydrated person do to boost hydration? Drink the sports drink and forget about enamel erosion? Or simply drink water and strive to survive? I personally think that if a dehydrated condition is present, one should definitely ingest a sports drink to correct an obvious imbalance, but on a hot day when thirst is due to temperature conditions or mild activity, water would be a better choice.

One possible remedy in the fight against dental decay would be for the companies that market sweetened sports drinks to include straws. But perhaps a simpler solution would be to just chew sugar free gum.

Mike


Questions and Answers

lemaym6 said... First of all, I don't understand the conclusion sentence, what will chewing sugar-free gum do to solve the issue?

Mike’s answer:

The sugar free-gum keeps your mouth “moisturized”. We all learned in biol.100 that sugar is the main source of food for the bacteria, especially for those found in our mouth. After the bacteria eats the sugar it will produce an acid that eventually deposits on your teeth and will eat the surface of your teeth called enamel, and than… tooth decay. One of the main causes for cavities is also from having a dry mouth. When your mouth is dry the acid (bacteria’s waste) has no interaction with the saliva and so the acid “eats” your teeth faster. Now, think of a runner who consumes a lot of sports drinks and than runs the marathon! On the other side people that sleep with their mouth open are at a greater risk for developing cavities. Now, don’t go too crazy on sugar-free gums, having too much of them may also be detrimental.

kamullig said... I'm just curious as to what straws would do?

Mike’s Answer:
It helps for the drink to go straight to the back of the mouth with minimum or almost no interaction with the molar teeth. This will definitely reduce the bacterial acid attacks on your teeth.

Retinal Implants

Researchers at Bonn University are developing a way of helping people who suffer from blindness. When light enters the human eye, it will eventually reach the retina. In the retina there are two types of photoreceptor cells, rods and cones. Cones allow us to see color and are effective in bright light. Rods are more effective in low light and allow us to see better in the dark. When light reaches the retina, the photoreceptor cells convert the light into nerve signals, which travel down the optic nerve, and into the brain where these signals are interpreted. When the retina becomes damaged, a person's vision will be damaged as well.

Now, there might be a way to help people with damaged retinas through the use to retinal implants. A thin foil is implanted at the retina with contacts that reach the ganglion cell layer. The ganglion cell layer is a layer of ganglion cells that receives information from the photoreceptor cells. A camera will send signals from the surroundings into the "Retinal Encoder," which converts the camera signal into a signal that the brain can use. This signal will be received by the contacts and will be sent into the optic nerve. The person will then be able to see an image on a screen in the glasses.

However, there are still many issues with this. One problem is that the brain might not be able to interpret the signals sent to the brain by these implants. In the first few months after we were born, our central visual system is adjusting to the retinal signals and our brain is constantly learning how to interpret those signals. With the retinal implants, a new set of signal is sent to the brain and so it must now learn how to interpret them. For adults, their central visual systems are already developed, which makes it difficult for it to learn interpret a new set of signals. Another issue is that these implants will not restore a person's vision completely, it will only allow them to see large objects and contours.

Although more research and testing is still needed, this looks to be very promising in the future.


yz

The Remains of Joan of Arc

Revised:

Recently, the remains of Joan of Arc were studied by Egyptian experts. The remains, as recognized by the church, are now housed in a museum in Chinon. Experts now say that the relics are actually made from the remains of an Egyptian mummy. Joan was burned at the stake in 1431 in Rouen, Normandy. The supposed remains were discovered in 1867 in a jar in the attic of a Paris pharmacy, with the inscription "Remains found under the stake of Joan of Arc, virgin of Orleans".

Philippe Charlier, a forensic scientist at Raymond Poincaré Hospital in Garches, near Paris, obtained permission to study the relics from the French church last year. Charlier and his colleagues only had a charred-looking human rib, chunks of carbonized wood, a 15-centimetre fragment of linen and a cat femur, which had to do with the medieval practice of throwing black cats onto the pile for burning witches.

To study the remains, the researchers conducted a series of tests, including: mass, infrared and atomic-emission spectrometry, electron microscopy, and pollen analysis. However, they also used an unusual technique known as Odor analysis. To help them in this technique, they called upon Sylvaine Delacourte from Guerlain, and Jean-Michel Duriez from Jean Patou, who are leaders in the perfume industry. Delacourte and Duriez sniffed the relics and nine other samples of bone and hair from Charlier’s lab without being told what the samples were. They were also not allowed to confer with each other. They both smelled hints of burnt-plaster and vanilla.

The plaster smell was consistent with the fact that Joan of Arc was burnt on a plaster stake, not a wooden one. However, vanilla is not a product of cremation. It is produced during decomposition. That means that it would not be found on someone who was burnt.

Microscopic and chemical analysis of the black crust on the rib and the cat femur showed that they were not burnt but were infused with a mineral matrix; and had no trace of muscle, skin, fat or hair. "I see burnt remains all the time in my job, it was obviously not burnt tissue." says Charlier. The cloth used for mummy wrappings were coated with a similar substance. The material used in wrappings was also consistent with gypsum, which causes the plaster smell.

The researchers also dated the remains using Carbon-14. The results stated that the remains came from between the third and sixth centuries BC. Spectrometry profiles of the rib, femur, and black chunks matched those of Egyptian mummies from that period. They did not match those of burnt bones.

Even though the remains were shown to be those of a mummy, I don't think it will change peoples' opinion on whether the story of Joan of Arc really happened or not.

http://www.nature.com/news/2007/070402/full/446593a.html

-WildThing

Study Shows that Stem Cells Provide Alternative Treatment for Diabetes

While a student at UMass, some of the closest friends I’ve made happen to have Type I diabetes. I’m surprised at how little I hear about research on this topic.

Type I diabetes is an autoimmune disorder. At an early age, usually before 20, the immune system begins attacking cells on the pancreas’ islets of Langerhans that are essential to the production of the hormone insulin. Insulin is needed to pass glucose from the bloodstream into the cell where it can be used as fuel. Without insulin, glucose levels in the blood increase and cells throughout the body starve. Type I diabetics inject synthetic insulin every day to make up for the function their pancreas no longer has. Unfortunately, injecting insulin is an imperfect science and also an uncomfortable procedure.

As a biology major who sees the daily affects of diabetes on life, I’m always curious about current studies and experimental treatments related to the disorder. Recently I came across the article “Stem Cell Transplant Resets Immune System in Type I Diabetes” which described an experiment that allowed Diabetics to go without insulin injections for up to 35 months.

Patients involved in the study had blood taken from which adult stem cells were filtered out. They were then placed on drugs to suppress their immune system. The adult stem cells were then injected into each of the patients.

During a 7- to 36-month follow-up, 14 patients became insulin-free (1 for 35 months, 4 for at least 21 months, 7 for at least 6 months; and two with late response were insulin-free for 1 and 5 months, respectively.) Among those, one patient resumed insulin use one year after the therapy. The only severe adverse effects were pneumonia in one patient and endocrine dysfunction in two others

It is thought that the study provided temporary relief from diabetes because the body was allowed to rebuild the immune system.

This study has some amazing results but there is still so little known about why people have Type I diabetes. Also, the study was performed on diabetics who were all diagnosed within 6 weeks prior to the experiment. The pancreas of each diabetic studied would still be relatively healthy. It is unknown how this study would affect people who have had Diabetes for longer periods of time. Although there is a lot more to learn about Type I diabetes, it is great to know that adult stem cells may be able to provide relief to many in the future.

APentowski

The Dolphin Brain

Dolphins are generally friendly and popular animals to many people. Dolphins charm people with their performances in an aquarium, and dolphins are used in animal therapy to help patients with psychological problems. In addition, dolphins are very intelligent, and their abilities have been studied for a long time. Due to their large brain size, dolphins have high intelligence. Emory University researchers studied the 47 million years of evolution of brain size of dolphins and their relatives, and the researchers found some similarity of the evolution of the brains of dolphins and humans.

First, the researchers used the fossil record of the toothed whales, dolphins, porpoises, belugas, and narwhals from the order Cetacea and suborder Odontoceti. This is because the modern species, odontocetes have quite a high ratio of brain size to body size. The ratio is the second highest after modern humans. So the researchers hypothesized that there is a pattern for the ratio in toothed whales, and the solution could make odontocete brain evolution more clear. In order to study the evolution of their brains, the researchers measured the ratio of brain size to body size for 60 fossil cetacean species and 144 modern cetacean specimens with tomography to scan and measure their skulls. They used a total sample of 210 specimens from 37 families and 62 species.

From this study, the researchers found two phases in dolphins’ evolution. The first phase was that the new suborder odontocetes emerged about 39 million years ago. Their brain size gradually increased, and the body size decreased. In addition, this change started from the first cetaceans that possessed echolocation. Echolocation is a biological process that uses sound propagation under water to communicate from dolphin to dolphin, and modern dolphins and other odontocetes use echolocation. The second change of brain size occurred in the origin of Delphinoidea; oceanic dolphins, porpoises, belugas, and narwhals emerged about 15 million years ago. Also odontocetes have showed high behavioral abilities such as recognition of abstract concepts as humans have.
From these investigations, the researchers concluded that odontoces had similar features with humans in the process of brain evolution and not only humans, but also dolphins developed their brains evolutionally.

I think that further study is needed for proving the relationship between the brain evolution of dolphins and humans. This study still leaves ambiguous points. We will be able to learn new information about humans’ evolution through further study. In addition, I am especially interested in the behavioral abilities of dolphins. Their behavioral abilities include not only recognition of abstract concepts, but also self-recognition on a mirror and the comprehension of artificial, symbolic communication systems. These high behavioral abilities show dolphins’ high intelligence such as humans and great apes. I would like to research more concrete abilities of dolphins and the relationship between humans and dolphins based on the abilities.

posted by tsaori

Cohabitation and Divorce Rate

Cohabitation is defined as living together in a sexual relationship without being married. Since the 1960s, there has been a steady increase in the number of unmarried cohabitants. In 1960, a total of 439,000 in the United States reported that they were cohabitating with a person of the opposite sex. By 2000, the U.S. Bureau of the Census reported that this number had risen to 5.5 million.
A lot of marriages (a legally sanctioned union between a man and a woman) are now preceded by cohabitation, but in contrast to common-sense notions about the advantages of cohabitation before marriage, data on divorce patterns show that there is a greater risk of marital breakup among people who cohabitated. (Whitbourne, 2001)
I did some research (mainly with books, since all the papers on-line were not for free) and would like to share what I learned about the negative effects of cohabitation on long-term relationship.

There are five main reasons people engage in cohabitation. Economic advantages from sharing living expenses, less complicated dissolution when the relationship doesn’t work out, availability of more time to spend together, more opportunities to share sexual and emotional intimacy without getting married, and a way to “test” compatibility turned out to be the biggest reasons in general. If we look at these reasons more closely among the older adults, age groups of 40 and over, it turns out that most of the adults choose cohabitation as a means of avoiding marriage. They tend to avoid marriage to prevent their loss of financial benefits such as alimony, welfare, and pension checks. Fear of losing another spouse either by death or divorce is another factor, along with the pain and anger as a result of divorce.

Enormous amount of data show that health is negatively correlated to cohabitation.
Non-married people feel less healthy and have higher rates of mortality than the married- about 50 percent higher among woman and 250 percent higher among men. Also, cohabitating with number of different partners is proven to greatly increase the possibility of acquiring one or more STDs (sexually transmitted diseases). In addition, married are more likely to maintain better sex lives and generally feel more secure and healthy. Especially when it comes to pregnancy, women who are cohabitors tend to feel insecure and suffer greater amount of stress in general than married women, which is directly related to increased alcohol consumption, smoking, violence, and depression.

Much of the studies were consistent in showing negative effects on long-time relationship among cohabitants. This might not apply to all couples who undergo cohabitation, but it is definitely worth thinking about this problem in planning one’s life. I didn’t cover it here in my blog, but further research has revealed that remarriage after cohabitation also resulted in higher divorce rate.
Doctors and psychologists recommend having self-esteem and confidence about oneself and not to be engaged in series of cohabitation for mental and physical reasons.

Well, relationship is life, and nothing would be more important than having a happy and satisfying one. I hope my blog has given out some useful information, and I wish good luck to you all!!

Other sources sited:

Trends in marriage and cohabitation: the decline in marriage and the changing pattern of living in partnership. John Haskey, Population Trends 80; Summer 1995; OPCS

Premarital cohabitation and the probability of subsequent divorce: Analysis using new data from the General Household Survey, John Haskey, Population Trends 68: OPCS, HMSO (London 1992)

Posted by clearsky83

Swim Turtles Swim

When you think of a world renowned race that takes place on Patriot’s Day, what race do you think of? I’m sure “Marathon Monday” and the Boston Marathon come to mind, but after this year you may be thinking of a new race. And instead of humans running, the participants are turtles, and they are swimming. This year is the first ever “Great Turtle Race” and the course is set across the Pacific Ocean.

This event has been organized to create awareness and help save the Leatherback Turtle, which is on the endangered species list and almost extinct. This 100 million year old turtle has outlived the dinosaurs. The race’s organizers, The Leatherback Trust, hope to help restore the population and raise awareness.

Over the past 20 years, about 95 percent of leatherback population in the Pacific Ocean has vanished. This is mostly due to human activity such as fishing and the poaching of their eggs and nests. About ten years ago, over a thousand turtles nested at Playa Grande in Costa Rica, and now the number has dropped to under 100. It is possible that these turtles may become extinct within the next decade.

This is the main reason that The Leatherback Trust and 11 corporate sponsors have teamed up for the “Great Turtle Race”. Companies such as Microsoft, Travelocity, and Yahoo! are all getting there feet wet and doing their part to save the leatherbacks. Fans of this race and the leatherback turtle can also help by logging onto http://www.greatturtlerace.com/. Here you can pick a turtle that is in the race and watch its progress from April 16th to April 29th. Also on this website you can make donations to help save this species.

You can watch the journey of these eleven turtles, because they have been tagged with satellite communication devices that trace their exact location. These tracking devices will allow scientists and fans to keep track of every move they make along the way. You can also learn about different obstacles that these turtles have to face on their trips across the ocean, from fishing line and trawls to plastic bags and other debris.

The course that the leatherbacks will travel begins on the beaches of Costa Rica’s Playa Grande, where they nest, and head south to the Galapagos Islands. This course spans about 950 miles.

Stanford researcher, George Shillinger thinks that this race is going to be a huge step in helping out the leatherbacks. “It’s fascinating to consider that we are able to bring together these prehistoric animals with such cutting-edge science. The data provides a nearly real-time ‘turtle’s-eye view’ of animal behavior in relation to environmental change.”

Although there is no prize for picking the winning turtle, it definitely will help awareness for the endangered species worldwide. So before April 16th, log onto to http://www.greatturtlerace.com/ and check it out.

JJLongo

"Smart" Cancer Cures

The future of medicine is very bright. With the new, rapidly growing field of nanotechnology, doctors will yield powerful, yet tiny weapons against common ailments and bizarre diseases. From the ability to “switch” off or on certain genes to curing disorders like diabetes and obesity, nanotechnology is the path medicine has chosen to go down. The most promising area of nanotechnology is the production of “Precision-guided Cancer cures.”
As we all know, modern cancer cures are very invasive and often harmful to healthy cells of the body. Chemotherapy, for instance, destroys targeted cancer cells along with nearby healthy cells. With nasty side effects of nausea, irritable rashes, and rapid hair loss, chemotherapy shrinks tumors but is not always favorable for the patients. Nanotechnology is the remedy for harmful caner treatments.
Robert Langer of MIT and Omid Farokhzad of Harvard University are forerunners in the field of adapting of nanotechnology to cancer research. By filling nanoshells, small hollow carbon polymer spheres, with very small doses of chemotherapy drugs, Langer and Farokhzad hope to deliver the drugs directly to the cancer cells themselves. To guide the chemo filled nanoshell directly to the cancer cells, small molecules called aptamers are attached to the surface of the shell. The aptamers are designed to only bind to certain proteins which are located on the surface of the cancerous tissue. This allows these “smart” shells, to target cancer and release its deadly cargo into the cancerous tissue. This kills cancerous cells and leaves the surrounding healthy cells unscathed.
Early in 2006, Langer and Farokhzad published preliminary data based on animal testing. The data showed that the nanoshells destroyed prostate cancer cells in mice. Although this data is very promising, a few more years of animal testing needs to occur before human testing takes place. Langer and Farokhzad hope to finish their research by 2014. If all goes well the fight against cancer will drastically change with this technology.


Work cited: “Precision-Guided Cancer Cures” by Gregory Mone and Elizabeth Svoboda, Popular Science, August 2006

Posted By:
JMcNeill


Update:

First I would like to apologize for taking so long to update this blog. As to answer some of your questions: Human studies are not yet underway, the use of nanotechnology is currently being tested on mice. Although the article stated that they had success targeting cancer cells with the new nanotechnology, it did not comment on the relative “controllability” of the nanoshells. As of now, no literature that I have found goes into much detail about the “controllability” or even the negative side effects of these new nanoshells. As more research and literature is published on this topic, I will try to update the blog.


Thanks for all the comments.

JMcNeill

Resisting Resistance

Resisting Resistance

We all know about the antibiotic penicillin. It was discovered in 1927 by Alexander Fleming and since then antibiotics have saved many lives. However, the progress in saving lives that these antibiotics have made is coming to a slowdown due to the fact that relatively recently, microbes have begun to become resistant to antibiotics, they mutate just the tiniest amount and are able to get around the antibiotic and continue to make people sick! This is bad because not only do we have to continuously create new antibiotics, but the microbes are able to develop resistance to even the most powerful antibiotics and we can not make the antibiotics much more powerful or else they will do more harm then good to the person ingesting them. Vancomycin is an antibiotic that doctors are trying to keep as a last resort defense against pathogens. It is worried that bacteria will become resistant to this antibiotic too and then what will we do?

Over 30 years ago it was discovered that deleting certain genes prevents microbes from becoming resistant to antibiotics. Normally, microbes copy their DNA using DNA polymerase (an enzyme) which makes very few mistakes and therefore results in an exact copy of the microbe. No mutations occur and therefore the antibiotic would continue to work on these microbes. However, when a microbe is exposed to antibiotics it becomes “stressed” out and they copy their DNA using normally dormant DNA polymerases that cause many more errors. This is how the microbes mutate; almost by accident! This is quite interesting because it always seemed obvious that the reason these microbes were mutating was because of survival of the fittest. One microbe would mutate and survive and therefore all the microbes would soon be able to resist the drug too.

Hope is near. At the semiannual meeting of the American Chemical Society, researchers from California reported that they have discovered compounds that microbes can not mutate to become resistant too. Although these compounds are not antibiotics, if we could figure out how to do the same thing with antibiotics, or how to make them work alongside antibiotics, the problem of antibiotic resistant microbes would disappear! It may not disappear completely but it could drastically slow down the rate at which microbes mutate which would do us a lot of good. It is a very good thing that scientists are looking into ways to prevent resistance to begin with and are not just continually making new drugs. The better solution would be to figure out a way to keep the microbes from resisting rather than making new drugs everytime they do form resistance.

Floyd Romesberg, a chemist at the Scripps Research Institute in San Diego, California and colleagues decided to look into the phenomenon discovered over 30 years ago. 2 years ago they found that a gene called LexA is an important “on” switch for the DNA polymerase that causes error. They proved this via both in vitro and animal studies. Specifically, they looked for small, drug like molecules that inhibit LexA in microbes exposed to the antibiotic ciprofloxacin. Ciprofloxacin also prevents DNA replication. They screened over 100,000 compounds and found several LexA inhibitors that get inside microbial cells easily and stop bacteria from mutating. It is hard to get things inside microbial cells to begin with so this in itself is an accomplishment.

These compounds are not ready for clinical trials yet but a new biotech company called Achaogen has been created by Romesberg in South San Francisco to commercialize the technology. Hopefully this company will produce compounds that can then go into clinical trials! So if you are interested in these antibiotic resistant microbes, head on over to San Francisco and find the answer!

One important thing to note is that individuals too can play a part in preventing antibiotic resistance. They can do this by simply using antibiotics less; only when absolutely necessary. This will decrease the ability of microbes to become resistant since there is nothing for them to become resistant to! This has actually been proven with penicillin. Read this article for more information.

Posted by KMellman

Chocolate Not Just Good for the Soul; but Good for Your Heart

I stumbled upon some research that showed that the thing that I am addicted to may actually be good for my heart. My drug of choice is chocolate. In 2002 at the American Association for the Advancement of Science’s the research regarding chocolate and the heart was introduced. It is the flavonoids that are found in chocolate that may have a beneficial affect on cardiovascular health. Flavonoids are compounds found in plants that contain potent properties of antioxidants. Currently there are more than 4,000 flavonoids known and the flavonoids found in cocoa are called flavonols; the Mars Corporation has developed a way to produce chocolate bars in which these rich flavanols are preserved, so they are not just found in cocoa or dark chocolate..

Two different studies regarding the affects of chocolate on cardiovascular health were performed. The first study in this research was performed by Dr. Norman K. Hollenberg and his team. Hollenberg noticed the blood pressure of native people of the Kuna Island in Panama. Hollenberg observed that the people of Kuna never suffered from high blood pressure; he also noted that these people drank at least five cups of cocoa (chocolate) a day. Hollenberg discovered that cocoa with more amounts of flavonols was correlated to a higher activity of nitric oxide. Nitric oxide is known to promote a healthy flow of blood in the body and through the heart, and to also lower blood pressure.

A second study in this research project was performed based upon the affects that cocoa may have in clotting and blood flow. It was noted by Dr. Carl Keen that cocoa (in certain amounts) shows the same affects on the heart as aspirin does (not many other comparisons are known between cocoa and aspirin). Cocoa, as it seems, make it harder for platelets to bond together; making clotting in arteries less likely to occur, encouraging healthier blood flow.

A team of Italian researchers also found the same results of eating or consuming cocoa on blood pressure. However, this team also noted that the consumption of cocoa may improve the health of people suffering from diabetes, because stroke and cardio vascular problems are a larger risk for people with this disease. They noticed that the flavonols in cocoa also made the metabolism of sugar of people with diabetes better; the breakdown of sugar was more rapid.

It must be said, by all the researches of these studies that the consumption of cocoa must still be in moderation. As much as cocoa has good affects on the heart and the body, it is still filled with fat. The amount of flavonols in cocoa is equivalent to the amount in red wine and green tea. So for chocolate lovers realize that you may be improving your health without even being aware.

-kamullig

I, Caterpillar: A New Wave of Robots Wriggles & Squirms into Existence

Were Isaac Asimov alive today, he would surely laugh at the simplicity of the idea….Robotic devices that mimic caterpillars and worms rather than relieving humans of mundane or stultifying repetitive tasks. Dr. Barry Trimmer of the Robotics Lab at Tufts University [1] www.nytimes.com/2007/03/27/science] is doing his best to make a robot that can slither along, burrow and flex almost like the real thing. Hopefully, these small, worm like machines will one day be used to locate landmines, and fix machinery in hard to reach places as well as finding a use in the diagnosis and treatment of disease. Dr. Trimmer, a neurobiologist, is fascinated with the idea of using small machines to fix larger ones and robots make such a reality possible, but not in the shape or form in which we have come to expect them in.
Conventional robots, no matter how well constructed have a limited range of motion because hard joints don't allow expanded angularity of movement. "Each joint adds exponential problems of control," says Dr. Trimmer. Consider the robotic arms of the space shuttle, perhaps the most advanced use of a robotic device at the present time. While these mechanized arms can achieve an astounding range of positions, each and every movement requires an incredibly complex feat of engineering.
Researchers chose to mimic the caterpillar because it has an efficacy in movement that is energy efficient and elegantly simplistic. The robotic caterpillar prototype consists of a silicone rubber exterior wrapped around hair-thin wires that form a zig-zag line extending the length of its artificial body. Dr. Trimmer's creation is essentially a hollow tube with wire springs that act as 'muscles'. The springs are fashioned from a shape-memory alloy, and when heated by electrical current, constrict. When the current is turned off they expand returning the pliable shell to its original shape. A rudimentary form of segmental locomotion to be sure, but they are moving and with nanotechnology such a popular field of interest at the moment, who knows what kind of 'freight' these little buggers will eventually carry and where they will carry it.
David Kaplan, a biomedical engineer at Tufts, is working on an alternate application to silicone rubber shell, hoping to adapt a material based on spider silk, which would be biodegradable. The operating system for these tiny robots is currently being developed. Unlike the intricate engineering software required to operate the robotic arms of the space shuttle, these squirming (and somewhat unnerving) inventions will have their movements coordinated by genetic algorithms that will make them capable of locomotion and simultaneous multi-tasking. According to Dr. Kaplan, if these little guys can be produced in volume and at an inexpensive cost of less than a dollar per unit, their uses can only benefit humanity. Dr. Kaplan predicts, "These cheaply produced machines, could be crammed into a canister and shot into a minefield. Their hollow tube bodies would contain a simple power source and a device to detect mines as they wriggle across the terrain at random, stopping when they detect a likely mine."[2] www.iht.com/articles/2007/03/27]
While detecting landmines isn't exactly rocket science, the people at NASA who actually do deal in rocket science, are looking to build their own version of a small moving robot that does not use a wheel mechanism for locomotion. NASA is seeking devices that can move in a number of different ways without relying on wheels. “Wheels are a marvelous invention, but they have their place,” said Peter Will, a U.S.C. researcher working on the NASA project. "Bicycling on sand is hard, he said, while walking on it is easy." [3] www.technovelgy.com/ct/Science] Perhaps the next mars probe will have a robotic caterpillar packed as a "Plan B" contingency, so if the wheels fall-off it can still wriggle it's way along the Martian landscape.

CatherineS
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[1] www.nytimes.com/2007/03/27/science/27robo.html?ex=1175832000&en=76788c41438243f3&ei=5070
[2] www.iht.com/articles/2007/03/27/business/robots.php
[3] www.technovelgy.com/ct/Science-Fiction-News.asp?NewsNum=953