Wednesday, January 31, 2007

Making Antibiotics More Effective

Making Antibiotics More Effective

Boost to Antibiotics Effectiveness

Source: scenta

Washington, Jan. 29 (ANI): Health experts say that a new approach based on bacteriophages may reduce the requirement of antibiotics while treating various diseases by up to 50 per cent.

It is possible because of the ability of certain bacteriophages to boost the effectiveness of antibiotics gentamicin, gramacidin or tetracycline, says Steven Hagens, previously at the University of Vienna.

He told Chemistry and Industry, the magazine of the SCI, that phages' have the ability to channel through bacterial cell membranes that boosts antibiotic effectiveness.

Hagen explained the working of phages with an example of 'pseudomonas bacteria, known for causing pneumonia and hospital-acquired infections.

These bacteria are particularly multi-resistant to antibiotics because they have efflux pump mechanisms that enable them to throw out antibiotics, but Hagen said that a pore in the cell wall could cancel the efflux effect.

Experiments in mice revealed that 75 per cent of those infected with a lethal dose of Pseudomonas survived if the antibiotic gentamicin was administered in the presence of bacteriophages, while none survived without the phages.

Hagen said that the bacteriophage approach would particularly be useful for treating cases of food poisoning, as the lower doses of antibiotic needed would not disrupt the friendly bacteria in the gut.Jim Spencer, a lecturer in microbial pathogenesis at the University of Bristol, welcomed the new approach, as the overuse of antibiotics since the 1940s had slowly created a host of infections that are resistant to antibiotics. '

The prospect of using such treatments to prolong the life of existing agents and delay the onset of widespread resistance is to be welcomed,' said Spencer. (ANI)


Antibiotics in the Human Food Chain

Antibiotics in the Human Food Chain
Antibiotic resistancy remains issue in EU and US

31 jan 2007

Despite declines of in-feed antibiotics, totally in the EU and partly in the US, resistancy issues are still a problem, according to scientists and livestock industry members.

The 2005 DANMAP report from the Danish government's programme for surveillance of European antimicrobial resistance, the most recent statistics available, says: "Antimicrobial consumption in food animals is still low compared to the total consumption before the cessation of growth promoter use." A chart in the report also says antimicrobial use in animals levelled in 2004 and 2005. At the same time, the use of antibiotics in humans has held about steady from 1997 through 2005, the DANMAP report showed.

US cuts back on antibiotics

The US Food and Drug Administration (FDA) says about 70% of infection-causing bacteria are resistant to at least one of the drugs most commonly used to treat infections in humans. The FDA site does not say where these bacteria acquired their resistance, but says use of antibiotics in animal feed can cause microbes to become resistant to drugs used to treat human illness.

In the US, sub-therapeutic antibiotic use, or below the level required to cure a sick animal, in livestock and poultry feed has declined in the last three years, according to Ron Phillips, vice president of legislative and public affairs for the Animal Health Institute. Antibiotics are being removed from animal feeds because consumers want them removed. In July 2005, the FDA removed its approval for Baytril for use in chicken feed because of its similarity to human antibiotics and concerns about resistant diseases. "These trends correspond to an increase in therapeutic use to treat a higher numbers of sick animals or birds. It "is precisely what is taking place in Europe," Philips added.

Farmers and veterinarian response

A Western Kansas veterinarian with a large cattle feedlot practice said many of his clients continue to use low-dose antibiotics as growth promoters because they work and because there are no comparable human drugs in use. In essence, it wouldn't matter if the animal's bacteria developed resistance to these drugs, because the bacteria still would be susceptible to human drugs, he said.

An Iowa veterinarian also said there is talk among pig producers of cutting back on antibiotics in feed, but "it's a necessary part of production." They are fed not only as a growth promoter but to prevent pneumonia and scours, or diarrhoea, he said. As if to underscore this need, the FDA recently approved another antibiotic for feed use in pigs, although it is to be done by "veterinary directive" only, the Iowa veterinarian said.

The biggest issues in the cattle industry are whether or not cattle feeders will be allowed to continue to feed tylosin phosphate (to prevent liver abscesses) and/or monesin (to prevent coccidiosis, an intestinal disease in cattle)," said Gary Smith, Colorado State University professor of meat sciences.

The answer: Few and effectiveAccording to Michael Hansen, senior scientist at the Consumers Union, which publishes Consumer Reports, the ideal rule-of-thumb is to keep livestock away from antibiotics unless they are needed, and then to treat as few as possible with an effective dose. External links:FDAConsumers Union

All About Feed

Thursday, January 25, 2007

Sanitation Beats Antibiotics, Vaccines on Greatest Medical Advances List

Sanitation Beats Antibiotics, Vaccines on Greatest Medical Advances List

Monday, January 22, 2007
By Miranda Hitti


Sanitation is the greatest medical advance since 1840, according to voters in a poll on the medical journal BMJ's web site.

The runners-up: antibiotics and anesthesia, says BMJ (formerly the British Medical Journal).
Last year, BMJ invited readers to submit nominations for the top medical breakthrough since 1840, the year the journal was launched.

BMJ then posted 15 nominations and invited people to vote on its web site between Jan. 5 and Jan. 14, 2007.

Votes poured in from more than 11,000 people (mainly doctors) in countries including Australia, Bulgaria, Canada, Germany, India, Italy, Spain, U.K., and the U.S.

Here, in order, are the results:

1. Sanitation: 1,795 votes.The importance of clean drinking water and waste disposal was recognized in the late 1800s, as diseases began to be linked to impure water. However, the World Health Organization says there is still a long way to go. More than 1.1 billion people now lack access to drinking water from an improved source; 2.6 billion do not have basic sanitation.

2. Antibiotics: 1,642 votes.Alexander Fleming, a British bacteriologist, discovered penicillin in 1928 by accident when he sloppily left a Petri dish of bacteria unwashed in his lab. He found a substance (later named penicillin) growing on it that killed the bugs, and modern-day antibiotics got its start. Fleming shared the Nobel Prize in 1945 for the discovery.

3. Anesthesia: 1,574 votes.In 1846, a Boston dentist used ether during surgery, putting an end to much of the pain of operations. Since then, general anesthesia has become a mainstay.

4. Vaccines: 1,337 votes.Vaccines have helped prevent a variety of diseases -- including polio, whooping cough, and measles. The first was Edward Jenner's smallpox vaccine, in 1796.

5. Discovery of DNA structure: 1,000 votes.Scientists James Watson and Francis Crick presented the structure of the DNA helix, the molecule responsible for carrying genetic information from one generation to the next, in 1953. It earned them the Nobel Prize in 1962.

6. Germ theory: 843 votes.In the late 1800s, Louis Pasteur was the first to suggest that disease is caused by exposure to microorganisms. Others furthered the theory, showing that specific diseases are caused by specific "bugs."

7. Oral contraceptive pill: 842 votes. The pill arrived on the U.S. market in 1960. For women who use it correctly, oral contraception can be up to 99% effective at preventing pregnancy.

8. Evidence-based medicine: 636 votes.As the name suggests, evidence-based medicine involves making use of the current best evidence (such as research), combined with a patient's values and a doctor's clinical experience, to make decisions about patient care. The term was coined in the early '90s and the concept has been evolving ever since.

9. Medical imaging: 471 votes.The X-ray was accidentally discovered in 1895. Since then, the field has expanded, giving us computed tomography (CT scans), positron emission (PET scans), magnetic resonance imaging (MRIs), and ultrasound.

10. Computers: 405 votes. From medical records to insurance, to making sure your new medication isn't going to clash with an existing one, computers are now considered as important as their stethoscopes by some doctors. They've been in use in medicine since the early 1960s. Doctors can access information on new drugs and interactions, new medical studies, and clinical trials, and keep patient records stored at their fingertips.

11. Oral rehydration therapy: 308 votes.This therapy involves giving fluids by mouth to replace losses by the body. It was first reported in 1964; now it's a mainstay of treatment in patients with cholera, acute diarrhea, and other conditions.

12. Risks of smoking: 183 votes.The first report of the connection between smoking and lung cancer was published in BMJ in 1950. Even so, tobacco use still kills an estimated 440,000 Americans each year.

13. Immunology: 182 votes.The history of immunology is traced to 1798, when Edward Jenner found that people could be immunized against the disease smallpox. Numerous other immunology discoveries followed, leading to a greater understanding of such things as allergies and antibodies.

14. Chlorpromazine: 73 votes.Discovered in 1952, chlorpromazine (Thorazine) was the first antipsychotic medication. It was used to treat psychotic disorders and their symptoms, such as hallucinations, hostility, and delusions. Its development brought new understanding of the biological basis for mental illness, and some say it provided more humane management.

15. Tissue culture: 50 votes.Tissue culture (keeping tissue alive and growing it in a culture medium for research or other purposes) was "discovered" in 1907; but it took until the 1950s for it to become an important tool for clinical investigation.

By Miranda Hitti, reviewed by Louise Chang, MD

SOURCES: News release, BMJ. WebMD Medical News: "What's the Greatest Medical Advance?"


Monday, January 22, 2007

Antibiotic efflux pumps in Gram-negative bacteria: the inhibitor response strategy.

Antibiotic efflux pumps in Gram-negative bacteria: the inhibitor response strategy.

J Antimicrob Chemother. 2007 Jan 17
Mahamoud A,
Chevalier J,
Alibert-Franco S,
Kern WV,
Pages JM.

UMR-MD-1, Facultes de Medecine et de Pharmacie, Universite de la Mediterranee, 27 Boulevard Jean Moulin, F-13385 Marseille Cedex 05, France.

* Corresponding author. Tel.: +33-4-91-32-45-87; Fax: +33-4-91-32-46-06; E-mail:

After several decades of continuously successful antibiotic therapy against bacterial infections, we are now facing a worrying prospect: the accelerated evolution of antibiotic resistance to important human pathogens and the scarcity of new anti-infective drug families under development. Efflux is a general mechanism responsible for bacterial resistance to antibiotics. This active drug transport is involved in low intrinsic susceptibility, cross-resistance to chemically unrelated classes of molecules, and selection/acquisition of additional mechanisms of resistance.

Thus, inhibition of bacterial efflux mechanisms appears to be a promising target in order to (i) increase the intracellular concentration of antibiotics that are expelled by efflux pumps, (ii) restore the drug susceptibility of resistant clinical strains, and (iii) reduce the capability for acquired additional resistance. Structurally unrelated classes of efflux pump inhibitors (EPIs) have been described and tested in the last decade, including some analogues of antibiotic substrates and new chemical molecules. Among the current collection of EPIs, only a few compounds have been studied taking into account the structure-activity relationships and the spectrum of activity in terms of antibiotics, pumps and bacteria. While large efforts have characterized an increasing number of bacterial efflux pumps and generated several potentially active EPIs, they have not elucidated the molecular basis of efflux transport and inhibition.

Recent studies of pump-substrate complexes, the 3D resolution of the efflux pumps, the synthesis of novel compounds and molecular dynamic studies may generate new clues to decipher and select novel targets inside the efflux mechanisms and, finally, may result in a clinically useful molecule.

Key Words: antibiotic resistance , drug efflux pumps , efflux pump inhibitors

Oxford Journals

Tuesday, January 16, 2007

Modes and Modulations of Antibiotic Resistance Gene Expression.

Modes and Modulations of Antibiotic Resistance Gene Expression.

Clin Microbiol Rev. 2007 Jan;20

Depardieu F,
Podglajen I,
Leclercq R,
Collatz E,
Courvalin P.

Unite des Agents Antibacteriens, Institut Pasteur, 75724 Paris Cedex 15, France.

Since antibiotic resistance usually affords a gain of function, there is an associated biological cost resulting in a loss of fitness of the bacterial host. Considering that antibiotic resistance is most often only transiently advantageous to bacteria, an efficient and elegant way for them to escape the lethal action of drugs is the alteration of resistance gene expression. It appears that expression of bacterial resistance to antibiotics is frequently regulated, which indicates that modulation of gene expression probably reflects a good compromise between energy saving and adjustment to a rapidly evolving environment.

Modulation of gene expression can occur at the transcriptional or translational level following mutations or the movement of mobile genetic elements and may involve induction by the antibiotic. In the latter case, the antibiotic can have a triple activity: as an antibacterial agent, as an inducer of resistance to itself, and as an inducer of the dissemination of resistance determinants. We will review certain mechanisms, all reversible, that bacteria have elaborated to achieve antibiotic resistance by the fine-tuning of the expression of genetic information.

PMID: 17223624 [PubMed - as supplied by publisher]

Related Article:

Genetic linkage and horizontal gene transfer, the roots of the antibiotic multi-resistance problem.

Anim Biotechnol. 2006

Summers AO.

Department of Microbiology, University of Georgia, Athens, Georgia 30602, USA.

Bacteria carrying resistance genes for many antibiotics are moving beyond the clinic into the community, infecting otherwise healthy people with untreatable and frequently fatal infections. This state of affairs makes it increasingly important that we understand the sources of this problem in terms of bacterial biology and ecology and also that we find some new targets for drugs that will help control this growing epidemic.

This brief and eclectic review takes the perspective that we have too long thought about the problem in terms of treatment with or resistance to a single antibiotic at a time, assuming that dissemination of the resistance gene was affected by simple vertical inheritance. In reality antibiotic resistance genes are readily transferred horizontally, even to and from distantly related bacteria.

The common agents of bacterial gene transfer are described and also one of the processes whereby nonantibiotic chemicals, specifically toxic metals, in the environment can select for and enrich bacteria with antibiotic multiresistance. Lastly, some speculation is offered on broadening our perspective on this problem to include drugs directed at compromising the ability of the mobile elements themselves to replicate, transfer, and recombine, that is, the three "infrastructure" processes central to the movement of genes among bacteria.


Bacteriophage, Evolution, Integron, Plasmid, Toxic metal resistance, Transposon


Wednesday, January 10, 2007

Bronchitis and Antibiotics

Bronchitis and Antibiotics

Antibiotics Are Useless for Most Cases of BronchitisBut doctors keep prescribing them, contributing to bacterial resistance, study says


Most people who go to a doctor with the raspy breathing problem called bronchitis get an antibiotic. Most of them shouldn't, a new study contends.

Two physicians at the Virginia Commonwealth University School of Medicine surveyed the world literature on bronchitis -- research studies, clinical trials and anything related to bronchitis and its treatment.

"Physicians should be encouraged to avoid antibiotics in most cases," said Dr. Richard P. Wenzel, chairman of the department of internal medicine at Virginia Commonwealth and one of the authors of the report.

The findings are published in the Nov. 16 issue of the New England Journal of Medicine.
The primary reason for over-prescription of antibiotics is that most cases of bronchitis, which is inflammation of the tiny airways of the lungs, "are caused by agents for which we have no therapy yet," meaning viruses, Wenzel said. Only a small percentage of acute bronchitis cases are caused by bacteria that doctors can treat, such as whooping cough, he said.

Yet doctors keep prescribing antibiotics, he said. He estimated that 70 percent to 80 percent of bronchitis patients are given a course of antibiotics lasting five to 10 days.

That's a lot of antibiotics. One of every 20 American adults will get bronchitis in a given year, Wenzel said. A first reason for them not taking antibiotics is that the drugs cost money, in an era when the mounting cost of health care is a major concern, he said.

"And all antibiotics have side effects, such as rash, diarrhea and abdominal pain," Wenzel said. Side effects are acceptable only when a medication helps the patient, he said.

"The third reason for not prescribing antibiotics is the impressive pressure it puts on organisms to select more resistant strains, so that the ones we use will no longer be effective," Wenzel said. While economists worry about medical costs, physicians worry about antibiotic-resistant strains of bacteria.

With all those arguments against the practice, why do doctors still write those prescriptions?
One reason is convenience, Wenzel said. "Think of all the patients we have to move through the office," he said. "I could take 15 minutes to explain why an antibiotic is not needed or write a prescription in 30 seconds."

And bronchitis tends to be overlooked as a subject of medical interest, Wenzel said. "It isn't considered very jazzy," he said. "It doesn't get highlights in medical journals or educational conferences. I can't remember in the past 10 years hearing a speaker discuss bronchitis at a medical meeting."

The information on bronchitis is there for any doctor who cares to look. The American Academy of Family Physicians notes that "because acute bronchitis is usually caused by viruses, antibiotics... usually do not help." The academy recommends getting lots of rest, drinking lots of non-caffeinated fluids, keeping the indoor humidity high and waiting for the condition to go away "after a few days or a week." If coughing and other symptoms persist, it could be a sign of a more serious condition, such as asthma or pneumonia.

One big reason for antibiotic prescriptions is patient demand, said Dr. Jeffrey Chapman, director of interstitial lung disease at the Cleveland Clinic.

"But patients are getting more savvy," he said. "They understand that a lot of infections are viral and that giving them an antibiotic places them at risk."

People with the bothersome symptoms of bronchitis shouldn't insist on a prescription, Chapman said. They should understand that "it may be the best course of treatment not to give an antibiotic."

"The message is getting out, a little bit at a time," he said. "There is a better understanding than there was, say, 10 years ago, that sometimes an antibiotic is not the better treatment."


Sinusitis and Antibiotics

Sinusitis and Antibiotics

Antibiotics Mostly Useless for SinusitisStudy only shows benefit with bacterial infections, which are minority of cases

(HealthDay News) -- If you develop a mild sinus infection this winter -- or even a moderately severe one -- antibiotics won't necessarily speed your recovery, new research shows.

"In the vast majority of cases, rhinosinusitis is a self-limiting disease," said Dr. An De Sutter, of Ghent University Hospital in Belgium. "It can last 10 days or longer, but antibiotics do not influence the course of the disease."

So, if you don't have signs of complications or severe infection, such as a high fever or extreme pain, your best bet is to forgo antibiotics, rely on symptomatic treatments and wait for a natural recovery, De Sutter said.

De Sutter estimates that 50 percent to 70 percent of sinusitis patients are prescribed antibiotics. Although the drugs can effectively treat patients who develop bacterial sinusitis, they are ineffective against viral sinusitis, which represents the majority of cases.

In the study, De Sutter and her colleagues looked at 300 patients with mild to moderately severe sinusitis, 218 of whom received sinus X-rays. They randomly assigned patients to receive either amoxicillin or a placebo, asked them to keep a symptom diary and observed them for 15 days.

The researchers found that neither typical sinusitis signs and symptoms nor abnormal X-rays had any value in predicting the course of the disease. They also found that the disease lasted as long in patients taking amoxicillin as it did in patients taking a placebo, and that 247 of the patients recovered within 15 days.

Only two subjective complaints -- a general feeling of illness and reduced productivity -- predicted a slower recovery from sinusitis. "In patients who feel ill or who do not feel able to work, recovery will take a few days longer," De Sutter said. "But antibiotic treatment does not speed recovery in these patients."

"We don't know for sure why antibiotic treatment seemed to have no effect on the duration of the illness," De Sutter said. "But there two possible explanations: Either the illness and X-ray abnormalities were not caused by a bacterial infection, or if they were, the patients' immune systems were able to overcome the infection just as quickly without antibiotics."

The results of the study are published in the November/December issue of the Annals of Family Medicine.

"We advise antibiotic treatment only when patients have severe symptoms such as high fever and bad pain or if they have impaired immune function," De Sutter said. "This is a very small minority of patients. For all others, we advise 'watchful waiting.' "

Instead of prescribing antibiotics, doctors should focus on symptom relief: paracetamol for pain relief and intranasal decongestants in case of a blocked nose, De Sutter suggested. "Some patients experience subjective relief by inhaling hot steam," she added.

In a similar study in the same journal, researchers found the desire for pain relief was one of the main reasons why sore-throat patients demand antibiotics. They concluded that it may be preferable to treat such patients with pain medications instead of antibiotics.

In most sinusitis cases, De Sutter believes that doctors should resist patient demand for antibiotics. "Doctors should explain to patients that antibiotics do not make a difference in the speed of recovery and can cause side effects," De Sutter said. "In our trial, diarrhea was more frequent with antibiotics. Other known side effects include nausea, oral or vaginal mold or yeast infection, allergic reactions and colitis."

The over-prescription of antibiotics, especially in children, also can cause the upper respiratory tract to become colonized with antibiotic-resistant bacteria such as S. pneumoniae, De Sutter said. "These resistant bacteria may cause infections that are more difficult to treat and may be passed on to other people."

"This is an interesting study because it looked at a large population of people with acute sinusitis," said Dr. David Sherris, chairman of otolaryngology at the University at Buffalo in New York.

"Most people do not need antibiotic therapy unless symptoms persist for more than seven to 10 days," Sherris said. "Plain X-rays of the sinuses add little or nothing to the diagnosis and treatment of acute sinusitis."

But that doesn't mean that imaging is of no value in sinusitis cases, he added. With prolonged or recurrent sinusitis or complications, computed tomography (CT) is the test of choice and works well, he noted.

"Early referral to an otolaryngologist is indicated in the most severe cases or where symptoms are out of proportion with findings," Sherris said. "The specialist can perform nasal endoscopy and accurately assess the most subtle CT scan findings."

Although the new study confirms some observations that Sherris has made during years of clinical practice, it would have been stronger if it had used the symptom system from the American Academy of Otolaryngology Head and Neck Surgery, Sherris said. "It is more complete than the one presented in this article, and though not infallible, is better to diagnose acute sinusitis."

Sherris also faulted the researchers' choice of antibiotics. "Amoxicillin, unless used in very high doses, is not a good first line antibiotic in acute sinusitis," he said. "Amoxicillin-clavulanate [augmentin] is a better choice, and is now generic in the United States. If there is an allergy to penicillin, physicians should consider azithromycin or a respiratory quinolone."


The danger of not taking all of your prescribed antibiotics

The danger of not taking all of your prescribed antibiotics

By Dr. Tom Gross Marin Independent Journal (California)Copyright 2007 Marin Independent Journal, a MediaNews Group publicationAll Rights Reserved Editor's note: Dr. Tom Gross is the emergency medical services director for the Novato Fire Protection District. His column appears every Monday.

I answered a telephone call the other day from a neighbor, who told me that she had a sinus infection. She wanted to know if it was OK for her to take some antibiotics. I asked her, "What antibiotics?"

She said, "Oh, I don't know, just something I have left over from my last infection." She described to me her symptoms, which included a sore throat, nasal congestion and sneezing; in other words, a common cold and not a sinus infection. She told me that whenever she gets those symptoms, she takes some leftover antibiotics from her medicine cabinet for a few days, but just until she feels better. Even though her cold would have resolved on its own, she thinks that the antibiotics are curing her illness.

There has been some doomsday press recently about strains of bacteria that are resistant to antibiotics. It is not difficult to create your own strain of antibiotic resistant bacteria. You can do it yourself at home. In fact, most people do.

Here is an experiment that you can try. All you need is some dishes of culture medium, easily available from any biological supply house, some cotton swabs, and your own vial of leftover antibiotics from the last time that you did not take your medication as prescribed.

First, take the cotton swab, wipe it along the back of your throat and rub it on a culture medium. Put the culture dish in a warm, dark place, like at the bottom of a laundry hamper and wait.

After a few days, the culture medium will be teeming with little white mounds of bacteria that look like cookie dough and smell like a laundry hamper.

Take another swab and transfer some of the bacteria to a new culture dish. Grind up a few of your leftover antibiotics and sprinkle them in the dish, close the lid and put it back in the bottom of the laundry hamper.

After a few days, examine your experiment again. The areas in the dish nearest to the antibiotic powder will be relatively free of bacterial culture; that is, no cookie dough.

However, the bacteria that have grown will have survived despite the presence of antibiotics. You will have just created your own strain of antibiotic-resistant bacteria, and you may now consider yourself to be a world-class WMD bioweapons manufacturer. You can go one step further, by repeating the experiment with another antibiotic, and you can make a bacterial culture that has multidrug resistance.

This type of experiment is known as "in vitro"; that is, your experiment was carried out "in glass." You can also perform this experiment "in vivo"; that is, in a living organism. In vivo experiments carry more scientific validity than in vitro experiments because their results are shown to be valid in actual patients rather than merely in a glass jar.

People who take their antibiotics for less than the prescribed period of time are performing in vivo experiments on themselves.

By taking antibiotics for only a few days, they are killing off the bacteria that are most susceptible, and leaving the most resistant behind to survive. They have participated in a living experiment that has demonstrated the validity of Darwin's theory of natural selection.

By exposing bacteria to intermittent small doses of antibiotics, they have killed off the bacteria that are most susceptible and have selected for those that are antibiotic resistant.

Having grown in their throats an antibiotic resistant strain of bacteria, then their next sinus infection will be truly resistant to antibiotics. These resistant bacteria can also spread to other people.

You may read in the paper about deadly strains of antibiotic resistant bacteria, such as MRSA (methicillin resistant staph aureus) or VRE (vancomycin resistant enterococcus). You may read about strains of tuberculosis bacillus that are resistant to all five antibiotics used to treat this disease.

This is no joke. This threat is real. The next time that you read about strains of antibiotic resistant bacteria, ask yourself if maybe you have been a part of this great experiment. Do you have antibiotics at home in your medicine cabinet left over from the last time that you did not take them as prescribed?

Please don't ask for stronger antibiotics. They have not been invented yet.


Friday, January 05, 2007

Elective penicillin skin testing in a pediatric outpatient setting.

Elective penicillin skin testing in a pediatric outpatient setting.
Dec 2006

Jost BC,
Wedner HJ,
Bloomberg GR.
Division of Allergy and Immunology, Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA.

BACKGROUND: Adverse reactions associated with penicillin-type antibiotics are common in pediatric practice, leading to the subsequent unnecessary use of alternative antibiotics. IgE-mediated penicillin allergy represents only a fraction of these adverse reactions.

OBJECTIVES: To examine (1) the trend of penicillin skin test reactivity during a recent 10-year interval, (2) the relative distribution of specific reagents related to a positive skin test result, and (3) skin test reactivity as a function of reaction history.

METHODS: Penicillin testing using 3 reagents--benzylpenicilloyl polylysine, penicillin G, and sodium penicilloate (penicillin A)--was conducted in a prospective study of 359 consecutive patients referred to an outpatient pediatric allergy clinic between January 1, 1993, and May 31, 2003. We also retrospectively reviewed penicillin skin test results for 562 children previously tested between January 1, 1979, and December 31, 1992.

RESULTS: Between 1993 and 2003, the prevalence of penicillin skin test sensitivity markedly declined. Of all the positive skin test results between 1979 and 2002, either penicillin G or sodium penicilloate or both identified 34%, with sodium penicilloate alone responsible for 8.5%. The rate of positive skin test reactions was not significantly different between patients with vs without a history of suggestive IgE-mediated reactions.

CONCLUSIONS: A marked decline in penicillin skin test sensitivity in the pediatric age group is identified. The minor determinant reagents penicillin G and sodium penicilloate are both necessary for determining potential penicillin allergy. Relating history alone to potential penicillin sensitivity is unreliable in predicting the presence or absence of a positive skin test result.


Monday, January 01, 2007

Alternative to Antibiotics Developed at Technion-Isreal Institute of Technology

Alternative to Antibiotics Developed at Technion-Isreal Institute of Technology

December 2006

Researchers at the Technion-Israel Institute of Technology have discovered a new way to create effective substitutes for antibiotics based on a combination of amino acids and fatty acids. Bacteria are not able to develop resistance to these substitutes, so this is their great advantage, as commonly used antibiotics are increasingly losing their effectiveness.

Prof. Amram Mor and students in his Haifa research team - Keren Marinka and Shahar Rotem of the biotechnology and food engineering faculty - found a way to preserve peptides in the body. Peptides are tiny proteins found in all organisms that constitute part of the immune system. They last only a short time, even minutes, but the Technion researchers found a way to stabilize and preserve them in the body for hours by creating a unique structure. Their study was published recently in the journal Chemistry and Biology.

"We found a way to shorten the natural molecule and thus reduce the cost of its production, while at the same time making it more efficient so it can successfully fight bacteria and other pathogens," said Mor.

"With help from Prof. Uri Kogan and Dr. Irina Fortania of our faculty, we added fatty acid to the short molecule, and its activity improved even more. We are also able to decide which bacterium to attack with our peptides."

The researchers show in the article how they use a fatty acid to activate the peptide so it acts specifically against Pseudonomas bacteria, which usually causes lung infections. It is important that the peptide function specifically against the bacterium so as not to harm healthy cells or beneficial bacteria that form the natural flora of the body. The team thus produced a pseudo-peptide that breaks the pathogenic bacteria down.

"This involves selective and specific construction against traditional pathogens and increasing the efficacy of treatment while significantly reducing toxicity and side effects," Mor explained.

Mor has been studying peptides for 20 years, during which he isolated a group of these proteins taken from frogs that live in trees. He found that these peptides were no less effective over time than antibiotics, which need to become 100 times bigger in their dosage to kill pathogens as time passes. There is no need, he said, to increase the dosage of the peptides.

The Jerusalem Post