Category Archives: Health Care

More on the Problems with Bisphenol-A

Milwaukee Journal-Sentinel: Bisphenol-A, that plasticizer, gets a media reaming

But few reports that The Tracker has seen match, in fury and conviction, the lambasting that a team of Milwaukee Journal Sentinel reporters, Susanne Rust, Meg Kissinger, and Cary Spivak, have given to these things, especially bisphenol-A, in the last two weeks. They say they reviewed 250 papers, interviewed more than 100 scientists, industry reps, and government regulators, read thousands of pages of additional documents. They give it a one-two punch, with that second one the roundhouse. They are going for a knockout.

The stories make The Tracker, a person with a tendency to say “on the other hand…”, a little nervous. There aren’t many maybes in here, not much calibration. The reporters appear fully convinced bisphenol-A is a menace. I’ve heard reports on the stuff too, and it does give one the jim jams. But one seldom sees, as here and without equivocation, declarations that a recent government review was flatly biased in its selection of which studies to give most weight, the gov’t used outdated methods, it looked mainly at chemical industry-funded studies, it ignored academic and presumably unbiased work.

The original articles: Are your products safe? You can’t tell. Labels often fail to list compounds that can disrupt biological development – WARNING: The chemical bisphenol A has been known to pose severe health risks to laboratory animals. AND THE CHEMICAL IS IN YOU.

In the first analysis of its kind by a newspaper, the Journal Sentinel reviewed 258 scientific studies of the chemical bisphenol A, a compound detected in the urine of 93% of Americans recently tested. An overwhelming majority of these studies show that the chemical is harmful – causing breast cancer, testicular cancer, diabetes, hyperactivity, obesity, low sperm counts, miscarriage and a host of other reproductive failures in laboratory animals.

Studies paid for by the chemical industry are much less likely to find damaging effects or disease. U.S. regulators so far have sided with industry by minimizing concern about the compound’s safety.

I believe in there are real risks that should be addressed. And I am not convinced the regulators are doing a good job, see my previous post in April, 2007 on Bisphenol A.

Related: Flushed Drugs Pollute WaterFDA May Make Decision That Will Speed Antibiotic Drug ResistanceThe A to Z Guide to Political Interference in ScienceResearcher Provides Undisclosed Data to FDAScientists Denounce Global Warming Report ‘Edits’

People Have More Bacterial Cells than Human Cells

Humans Carry More Bacterial Cells than Human Ones

All the bacteria living inside you would fill a half-gallon jug; there are 10 times more bacterial cells in your body than human cells

The infestation begins at birth: Babies ingest mouthfuls of bacteria during birthing and pick up plenty more from their mother’s skin and milk—during breast-feeding, the mammary glands become colonized with bacteria. “Our interaction with our mother is the biggest burst of microbes that we get,”

there are estimated to be more than 500 species living at any one time in an adult intestine, the majority belong to two phyla, the Firmicutes (which include Streptococcus, Clostridium and Staphylococcus), and the Bacteroidetes (which include Flavobacterium).

probiotics – dietary supplements containing potentially beneficial microbes – have been shown to boost immunity. Not only do gut bacteria “help protect against other disease-causing bacteria that might come from your food and water,” Huffnagle says, “they truly represent another arm of the immune system.”

But the bacterial body has made another contribution to our humanity – genes. Soon after the Human Genome Project published its preliminary results in 2001, a group of scientists announced that a handful of human genes – the consensus today is around 40 – appear to be bacterial in origin.

How cool is science? Very, I think 🙂

Related: Tracking the Ecosystem Within UsBeneficial BacteriaEnergy Efficiency of DigestionLarge Number of Bacteria on our SkinWhere Bacteria Get Their GenesAmazing Science: Retroviruses

Fighting Tuberculosis

Signaling an End to TB by Kathleen M. Wong

Once routinely treated with cheap antibiotics, TB is poised to make a terrifying comeback. More and more, doctors in developing nations are finding patients infected with strains of TB invulnerable to all but a handful of extremely expensive, exotic drugs. Worldwide, TB already infects one in every three people and sickens one in ten. Without new methods to stop the spread of drug-resistant strains, the cost of treating this ancient human pathogen could bankrupt even the most prosperous economies.

TB could, in theory, develop resistance to this new class of drugs, too. But Alber thinks he can skew the odds to favor humans. Identifying a drug capable of knocking out several TB enzymes at once could make it next to impossible for the bacterium to evolve resistance on multiple fronts.

Though TB is a daunting foe, Alber remains confident about the prospects of beating the disease. “As a bacterium, it should be easier to treat than HIV or malaria. Those kinds of diseases-caused by viruses and protozoans-we generally don’t know how to cure,” Alber says. “From a scientific perspective, TB is a simpler problem.”

Good luck, it may be easier but it still isn’t easy. Related: Tuberculosis Risk‘Virtually untreatable’ TBExtensively Drug-resistant Tuberculosis (XDR TB)TB Pandemic Threat

Amazing Science: Retroviruses

One of the great things about writing this blog is I find myself more focused on reading about interesting science. Retroviruses are very interesting and frankly amazing. Darwin’s Surprise by Michael Specter, The New Yorker:

A retrovirus stores its genetic information in a single-stranded molecule of RNA, instead of the more common double-stranded DNA. When it infects a cell, the virus deploys a special enzyme, called reverse transcriptase, that enables it to copy itself and then paste its own genes into the new cell’s DNA. It then becomes part of that cell forever; when the cell divides, the virus goes with it. Scientists have long suspected that if a retrovirus happens to infect a human sperm cell or egg, which is rare, and if that embryo survives – which is rarer still – the retrovirus could take its place in the blueprint of our species, passed from mother to child, and from one generation to the next, much like a gene for eye color or asthma.

When the sequence of the human genome was fully mapped, in 2003, researchers also discovered something they had not anticipated: our bodies are littered with the shards of such retroviruses, fragments of the chemical code from which all genetic material is made. It takes less than two per cent of our genome to create all the proteins necessary for us to live. Eight per cent, however, is composed of broken and disabled retroviruses, which, millions of years ago, managed to embed themselves in the DNA of our ancestors. They are called endogenous retroviruses, because once they infect the DNA of a species they become part of that species. One by one, though, after molecular battles that raged for thousands of generations, they have been defeated by evolution. Like dinosaur bones, these viral fragments are fossils. Instead of having been buried in sand, they reside within each of us, carrying a record that goes back millions of years. Because they no longer seem to serve a purpose or cause harm, these remnants have often been referred to as “junk DNA.” Many still manage to generate proteins, but scientists have never found one that functions properly in humans or that could make us sick.

How amazing is that? I mean really think about it: it is incredible. The whole article is great. Related: Old Viruses Resurrected Through DNADNA for once species found in another species’ GenesNew Understanding of Human DNARetrovirus overview (Tulane)Cancer-Killing Virus
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Full Body 3-D CT Scan in Under a Minute

Pretty cool new gadget, though probably out of the range of most people’s budget – ‘Super’ scanner shows key detail

The new 256-slice CT machine takes large numbers of X-ray pictures, and combines them using computer technology to produce the final detailed images. It also generates images in a fraction of the time of other scanners: a full body scan takes less than a minute.

Because the images are 3D they can be rotated and viewed from different directions – giving doctors the greatest possible help in looking for signs of abnormalities or disease.

At present, it is only being used in one hospital: the Metro Health medical centre in Cleveland, Ohio, which has been using it for the past month.

the first commercially viable CT scanner, which was invented by Sir Godfrey Newbold Hounsfield in Hayes, United Kingdom at the company’s laboratories and unveiled in 1972. At the same time, Allan McLeod Cormack of Tufts University independently invented a similar machine, and the two men shared the 1979 Nobel Prize in Medicine. “This is a quantum shift from the first CT scanners as it gives a lot more detail,” says Dr Keith Prowse, Chairman of the British Lung Foundation.

Gates Foundation and Rotary Pledge $200 Million to Fight Polio

Did you think polio was cured decades ago? Well in the rich world is largely has been but it has not been eradicated everywhere. Gates Foundation, Rotary pledge $200 million to fight polio:

Scientists and public health professionals have been debating whether eradication is possible. Some have argued that resources should be directed at trying to contain the disease, which would be far less costly than trying to eliminate it entirely. That idea was dismissed at today’s announcement. “Eradicating polio is an achievable goal,” said William Gates Sr., co-chairman of the Bill & Melinda Gates Foundation.

Dr. Margaret Chan, director-general of the World Health Organization, said: “We have very few opportunities to improve the world in a permanent way. And this is one.” Polio has stricken untold millions around the world. In 1952, its peak year in the U.S., it paralyzed more than 20,000 Americans. But it became a disease of the past in this country after the discovery of a preventive vaccine in the 1950s and universal immunization.

The Gates grant comes at a critical time for the global initiative, which faces a funding shortfall of $650 million, officials said. Most of the initial $100 million will be spent on mass immunization campaigns, poliovirus surveillance activities, and community education and outreach in polio-affected countries.

In recent years, importation of the disease from affected areas into countries where the disease had been eliminated has set back eradication efforts. But last month the World Health Organization released data indicating that the last four polio-endemic countries were within reach of wiping out the disease. The health authority said significant progress had been made in India and Nigeria, which together account for 85 percent of the world’s polio cases.

Related: Indonesian Polio EpidemicRiver Blindness Worm Develops Resistance to DrugsGates Millennium ScholarsInternship with Bill GatesBill Gates Interview from 1993

Moringa Oleifera: The Miracle Tree

One thing I enjoy brought about by the web is finding interesting tidbits such as – Moringa Oleifera: The Miracle Tree:

For centuries, the natives of northern India and many parts of Africa have known of the many benefits of Moringa oleifera. Its uses are as unique as the names it is known by, such as clarifier tree, horseradish tree and drumstick tree (referring to the large drumstick shaped pods) and in East Africa it is called “mother’s best friend”. Virtually every part of the tree can be used. Native only to the foothills of the Himalayas, it is now widely cultivated in Africa, Central and South America, Sri Lanka, India, Malaysia and the Philippines. This tree, though little known in the Western world, is nutritional dynamite. There are literally hundreds of uses for this tree.

The immature pods are the most valued and widely used of all the tree parts. The pods are extremely nutritious, containing all the essential amino acids along with many vitamins and other nutrients. The immature pod can be eaten raw or prepared like green peas or green beans, while the mature pods are usually fried and possess a peanut-like flavor. The pods also yield 38 – 40% of non-drying, edible oil known as Ben Oil. This oil is clear, sweet and odorless, and never becomes rancid. Overall, its nutritional value most closely resembles olive oil. The thickened root is used as a substitute for horseradish although this is now discouraged as it contains alkaloids, especially moriginine, and a bacteriocide, spirochin, both of which can prove fatal following ingestion. The leaves are eaten as greens, in salads, in vegetable curries, as pickles and for seasoning. They can be pounded up and used for scrubbing utensils and for cleaning walls. Leaves and young branches are relished by livestock. The Bark can be used for tanning and also yields a coarse fiber. The flowers, which must be cooked, are eaten either mixed with other foods or fried in batter and have been shown to be rich in potassium and calcium.

More internet finds: Sarah, aged 3, Learns About SoapPlumpynut, Miracle FoodThe AvocadoMore Nutritious WheatCool Mechanical Simulation SystemAerogels – Weird SolidsAwesome Cat Cam

Disrupting Bacteria Communication

Princeton scientists break cholera’s lines of communication

A team of Princeton scientists has discovered a key mechanism in how bacteria communicate with each other, a pivotal breakthrough that could lead to treatments for cholera and other bacterial diseases.

The mechanism is a chemical that cholera bacteria use for transmitting messages to each other, known as CAI-1, and has been isolated in the lab of molecular biologist Bonnie Bassler. Her team has shown that the chemical also can be used to disrupt the communication that exists among the bacteria, potentially halting the disease’s progress. The discovery could lead to an entirely new class of antibiotics.

Higgins isolated the CAI-1 chemical, which occurs naturally in cholera. Then, Megan Pomianek, a graduate student in the laboratory of Martin Semmelhack, a professor of chemistry at Princeton, determined how to make the molecule in the laboratory. Higgins used this chemical essentially to control cholera’s behavior in lab tests.

The team found that when CAI-1 is absent, cholera bacteria act as pathogens. But when the bacteria detect enough of this chemical, they stop making biofilms and releasing toxins, perceiving that it is time to leave the body instead. “Our findings demonstrate that if you supply CAI-1 to cholera, you can flip their switches to stop the attack,” Higgins said.

Chemist Helen Blackwell of the University of Wisconsin-Madison praised the study, calling it a breakthrough for quorum sensing research, and possibly for medical science.

Related: Entirely New Antibiotic Developed to Fight MRSAHow do antibiotics kill bacteria?Antibiotic Discovery StagnatesHacking Your Body’s Bacteria

MRSA Blows Up Defender Cells

Superbug succeeds by blowing up defender cells, scientists learn

While only 14 percent of serious MRSA infections are the community associated kind, they have drawn attention in recent months with a spate of reports in schools, including the death of a 17-year-old Virginia high school student. Both hospital-associated and community-associated MRSA contained genes for the peptides. But their production was much higher in the CA-MRSA, the researchers said.

The compounds first cause inflammation, drawing the immune cells to the site of the infection, and then destroy those cells. The research was conducted in mice and with human blood in laboratory tests. Within five minutes of exposure to the peptides from CA-MRSA, human neutrophils showed flattening and signs of damage to their membrane, researchers said. After 60 minutes, many cells had disintegrated completely.

“This elegant work helps reveal the complex strategy that S. aureus has developed to evade our normal immune defenses,” Dr. Anthony S. Fauci, NIAID director, said in a statement. “Understanding what makes the infections caused by these new strains so severe and developing new drugs to treat them are urgent public health priorities.”

Related: MRSA Vaccine Shows PromiseEntirely New Antibiotic Developed

New and Old Ways to Make Flu Vaccines

New and Old Ways to Make Flu Vaccines by Nell Greenfieldboyce, NPR:

Standard Practice
Pros: Millions of Americans receive this [standard] vaccine every year. It’s safe and well tolerated. Its production begins in hens’ eggs — a tried and true technology for 50 years.
Cons: Eggs must be ordered many months in advance, and millions of doses require millions of eggs.

Live-Attenuated Vaccine
Pros: This newer method of production results in a vaccine that has a flu virus that is crippled, so it can’t cause disease. But the virus is not killed, as is the case in the standard vaccine. The vaccine also can be given as a nasal spray.
Cons: More expensive than standard vaccine, and also produced in eggs. Not approved for young children or older people.

Cell-Based Vaccine
Pros: This vaccine can be produced in giant vats of living cells. Such a production method means it can be scaled up much faster than egg-based vaccines, making it more useful in a pandemic. Several versions have been tested successfully in people.
Cons: Won’t be widely available for a few years. Clinical trials are under way, but no flu vaccine made this way is currently approved by the Food and Drug Administration.

Related: MRSA Vaccine Shows PromiseAntibiotics Too Often Prescribed for Sinus Woes