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Posts Tagged "pathology"

The Artful Amoeba

Mystery of Alaskan “Goo” Rust Solved at Last

rust_spores_alaska_noaa_200

Last fall the small Alaskan coastal village of Kivalina was inundated by a mysterious orange “goo”(click for photo). Locals and others suspected a toxic algal bloom (see here for image), or perhaps some sort of chemical release, or millions of microscopic “crustacean eggs”. Yet just a month later the mystery substance was identified as none [...]

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Lab Rat

The pathogen detectives: sourcing the post-earthquake cholera outbreak in Haiti

this is not a pipe

Natural disasters such as earthquakes can have far-reaching effects beyond the damage caused on the day they occur. The 2010 earthquake in Haiti damaged the already limited sanitation systems leading to areas without adequate toilet and washing facilities; perfect for the spread of infection diseases. Sure enough 9 months following the quake there was an [...]

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Lab Rat

Innate immunity: the first line of defence

Scanning electron microscope of blood cells used in the innate immune response. Red blood cells are the smooth ones with the dent in the middle, white blood cells are round and knobbly.

The very first line of defence against any invasion of the human body is a set of physical barriers between the inside of the body and the outer world. Defence systems like the skin, tears and the stomach lining might not sound very impressive until you start to think of what happens when they don’t [...]

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Lab Rat

Evolving proteins – no DNA required

Light photomicrograph of brain tissue (magnified 100X) suffering from vCJD. Image from Public Health Image Library (PHIL) ID#: 10131

Prions are the infective agents that cause transmissible spongiform encephalopathies such as Mad Cow Disease in humans. All prions affect the brain or neural tissues and are currently untreatable. What makes them particularly fascinating is that unlike other infective agents such as bacteria, protozoa, and viruses, they don’t contain any genetic material. No DNA or [...]

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Lab Rat

The SOS response: how bacteria deal with damaged DNA

61px-Dna-split

DNA is important stuff. It’s present in all living organisms on the planet (or ‘almost all’ if you wish to remain friends with virologists) and contains the information required to produce and organise the proteins within a cell. If the DNA is damaged, the cell will very quickly find itself in danger. In multicellular organisms [...]

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Lab Rat

The bacteria in breast milk

Norse mother, by Albert Neuhuys (1844 - 1914) Image credit: www.rijksmuseum.nl

Bacteria are found in large numbers all over the human body where there is a channel to the outside world, for example in the gut, lungs, and surface of the skin. I’ve always thought that actually inside the human body was a bacteria-free environment unless an infection was raging so I was very excited to find [...]

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Lab Rat

Communication between kingdoms: the micro-organisms that live on the human body

Image from reference 2

From the point of view of a micro-organism, the human body is a prime piece of real estate. For those bacteria and fungi that can avoid or fight off the immune systems, a human provides a whole range of moist, nutrient-filled little spaces in which to live. Some of these micro-organisms are harmless, growing and [...]

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Lab Rat

Lab-work without a lab: culturing bacteria in rural areas with limited resources

Bottles of culture resting on phase-change packets inside an insulated container. Image from the reference.

In order to isolate, study and efficiently treat a bacterial outbreak, it is vital to be able to grow, store and identify the particular strains of bacteria that cause the disease. While this can be a fairly simple task in a well stocked laboratory, it’s a lot harder to achieve out in the field, in [...]

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Lab Rat

How bacteria get inside your house

HH_Lecture_Hall

Given that they occupy every other niche on earth, including deep sea vents, salt flats and the interior of human bodies, it should come as no surprise that bacteria are also found in human houses. Once inside, they can cause problems; airborne bacteria can be easily move between people and spread their corresponding diseases. Nowadays, [...]

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Lab Rat

How to eat your host: Pathways for nutrition in Salmonella

Salmonella typhimurium. Photo: Volker Brinkmann, Max Planck Institute for Infection Biology, Berlin, Germany. Image from reference 2.

From the point of view of an intracellular bacteria, the human body really is no more than just a habitat in which they must grow and thrive. While this particular habitat might have stable internal conditions, and less competition than the big open world, it has its disadvantages in continuous attacks from the immune system, and the [...]

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Lab Rat

The bacteria that use cholesterol to get into cells.

Diagram of the membrane that surrounds human cells. The two layers of phospholipids can be seen (blue and while spheres with the lipid tails pointing inwards) studded with bright red proteins. The yellow blobs within the phospholipid layer are cholesterol.

Although it usually only gets talked about when it starts causing problems, cholesterol is an important molecule to have in the body, as it is a component of cell membranes. The major component of cell membranes is a molecule called a phospholipid; an inorganic phosphate molecule joined onto lipid tails. Lots of these phospholipids all [...]

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Talking back

A Robot Helps Listen In on Brain Cell Chatter

Erwin Neher and Bert Sakmann received the Nobel Prize in Physiology or Medicine in 1991 for their development of the patch-clamp technique, which records currents coursing through single ion channels in cells. For neuroscientists, one form of this technique  has become the gold standard for probing information about the goings-on inside a cell. It can [...]

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