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Archive for the ‘antibiotics’ Category

One of the scary scenarios that is liable to be overlooked is bacteria that have become immune to antibiotics. To add fuel to it new classes of antibiotics aren’t being found as we would like to.

First of all we need to understand mechanism in nature has given bacteria similar strategies that we adopt in our present times*.

Bacteria evolve and learn to defend themselves. Bacteria need host as aliens a home. These may find their way into the blood stream through a cut just as easily migrants land off Lampedusa island in Mediterranean sea.

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The majority of antibiotics we use at home or in hospitals today have their origins in natural products.

The penicillins, cephalosporins, aminoglycosides, rifamycins, tetracyclines and glycopeptide-based antibiotics all came from bacteria or fungi. They were made by nature in response to selective evolutionary pressure over eons of “chemical warfare”, in which microorganisms battled to survive by killing off their competitors with antibiotics.

In a single scoop of soil, bacteria and fungi number in the millions. They also come in thousands of varieties, and survive by fighting each other. We know this because for the past century, several newly discovered antibiotics have been found by isolating them from the bacteria and fungi that produce them to defend their own lives.

Of course, they also co-evolved resistance mechanisms to avoid being killed by their own compounds, so antibiotic resistance is equally ancient. Scientists have found antibiotic resistance genes in bacteria isolated from 30,000-year-old permafrost, long before antibiotics were discovered and used by humans.

Most antibiotics found during the “golden age” were from micro-organisms themselves, isolated from soil or plants and then cultured in the laboratory. They were easily screened on agar culture plates or liquid culture broths to see if they could kill pathogenic bugs.

The toolkit required was pretty simple: some dirt, a culture flask to grow the antibiotic-producing bacteria or fungi, a column to separate and isolate the potential new antibiotic, and a culture plate and incubator to test if the compound could kill a disease-causing pathogenic bacteria.

Chemists were then able to “tweak” these new structures to extend their activity against different bacteria and improve their ability to treat infection in the clinic. Most of the antibiotics we have are derived from just one soil-dwelling bacterial order – the Actinomycetales.

We have somewhat exhausted our resources by exploiting what was easily found around us. So scientists have been forced to look further afield, turning to coral reefs, deep oceans and cave-dwelling bacteria to search for new promising molecules.

Key challenges

Philosopher Sun Tzu said “the supreme art of war is to subdue the enemy without fighting”. We are now in a protracted war against superbugs, as we have overplayed a key weapon against disease. Our unfortunate misuse and abuse of antibiotics means that bacteria have developed new ways to inactivate the drugs, to stop them getting to their targets within the bacteria cells, and to pump them back out of the cell when they do get in.

The cost and time required to bring new drugs to market are staggering. Estimates for the time to bring a new antibiotic through the preclinical, clinical and regulatory approval process are in the order of 13 to 15 years and around US$1.2 billion. If the costs of failures are factored in, it is closer to US$2.5 billion.

Because we expect to pay $20 or at most $200 for a course of antibiotics (compared to more than $20,000 for many cancer treatments), and because we only take antibiotics for a week or two, almost all of the companies that were active in antibiotic discovery have left the field over the last 20 years.

Tail spin:

*Evolution of free societies thanks to multiculturalism allow sneak attacks from host of aliens that have gained entry under different pretexts. Some are benign but faith based Jihadists who are more likely impressionable youth finding welfare programs of the host nation to fund their layabout lifestyle too attractive to miss the freeloading so they could hang out with friends of same attitudes. These naturally have no skills nor care to develop for their betterment or others. If they find themselves marginalised as sure as their choices would indicate they will know whom to blame. Their host nation of course. (Have you ever found any of them feeling they are parasites or blame lay in their own choices? No never.) What little they know is they are likely recruits for different groups who want to impose their own agenda when the time is opportune. An apt example would be the recent 8 Jan. attack in Paris. The terrorist brothers under the behest of Yememi branch of al-Qaeda imagined that by attacking Charlie Hebdo on the issue of Prophet Mohammad cartoon they could strangle free speech and make a dent in the tenor of the French society. Had they succeeded they would sooner or later upped their ante by escalating their hold by demanding something else similarly spacious. Hitler tried it before them and got away. (Had these terrorists honored the intent of the prophet instead of a silly point of blasphemy involved in portraiture, much of this bloodshed would have been needless.)

Such evolution is inevitable since the bacteria also mimic the host in many areas while seeking their opportunity. Under free speech in Park View schools, in UK impressionable minds were being groomed to view white women are devoid of all morals and similar lies. These hate strategies under faith based school management were caught in camera in time. When bacteria evolves similarly into malignant tumours superior technology must be relied to neutralise them.

Ref. Birmingham mail’of 26/7/14-Trojan Horse

Matthew Cooper/the Conversation/14/1/15-We need new anti-biotics

benny

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