DISENCHANTED

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Helacyton gartleri

The immortal remains of Henrietta Lacks.

When human body cells are removed and put into a cell culture, they weaken and die quickly, usually within about 50 divisions. Without the rest of the support structure—a heart, blood circulating, a digestive system and so-on—body cells can't survive. Body cells also age, so even if you were to simulate the body's environment in a test tube or petri dish, the cells would eventually perish anyway. The basic mortality of the cells reflect the basic mortality of the organism they comprise, which is why there's no fountain of youth or medicinal procedure that'll give you biological immortality.

There is, however, one human being who is biologically immortal on a technicality, and her name is Henrietta Lacks. In 1951 she showed up at John Hopkins Hospital in Baltimore, complaining of blood spotting in her underwear. Samples were taken of her cervical tissue and sent to a lab for analysis, which came back with a diagnosis of cervical cancer.

The cancer was caused by the Human papillomavirus, which is a sexually transmitted disease. Most variants of this virus are harmless, but some are known to cause cervical cancer, as in Henrietta's case. After her diagnosis and before attempts to treat the disease with radium, another sample from the tumor was sent to George Gey, who was the head of tissue culture research at Hopkins. Gey discovered that the cells from Henrietta's tumor would not only survive and multiply outside of her body, but they didn't age either. These cells were basically immortal.

And they're still alive, even though Henrietta herself died of the cancer on October 4th, 1951. Now, HeLa cells are about as common in biological research as the lab rat and the petri dish, and are still being grown in an unbroken lineage from the cells originally harvested from Mrs. Lacks in 1951. They're used in cancer research because a scientist can perform experiments on them that otherwise couldn't be done on a living human being. They were also used in the development of the Polio vaccine, making Henrietta somewhat of a posthumous hero to millions.

But say you're a scientist looking at HeLa cells under a microscope. They live independently of the body they came from. They reproduce (faster even than other cancerous cells). They consume, excrete, and do everything an independent living organism usually does. A thousand years from now there will still be HeLa cells multiplying and living, even some of the original cells sampled from Mrs. Lacks, even though Henrietta Lacks herself has long since passed away. Is this a new species?

In 1991 the scientific community decided it was, and blessed HeLa cells with its own genus and species: Helacyton gartleri, named by Van Valen & Maiorana.

That would make Helacyton gartleri an example of speciation, which is when a new species is observed developing from another. In this case, the development is from a chordate (homo sapien) to something that's more like an ameoba (a cross-phylum mutation), giving us an animal with a mostly human genotype, but which does not develop into a human-like phenotype. Since this event occurred in nature when the papillomavirus transformed Henrietta's cells, and not in the laboratory, it's a strong piece of evidence supporting Evolution (although not one that suggests you could go from an ameoba to a chordate, which would probably take more than one mutation).

is a deterministic entityD  categorized by MedicineD  categorized by BiologyD  

2004-04-24 21:54:15.480123-05 Best permanent link

al-Khwarizmi

780 - 850AD, grandfather of computer science, popularizer of Arabic numerals, adopter of zero (the symbol, that is) and the decimal system from India, astronomer, cartographer, all-around smarty pants.

The modern word algorithm is derived from Abu Ja'far Muhammad ibn Musa al-Khwarizmi, one of the better known Persian mathematicians, mostly thanks to his book, Hisab al-jabr w'al-muqabala.

al-jabr, which means "completion" or "transposition", was later mangled into algebra, for al-Khwarizmi's book was the first we know was written on the subject. In al-Khwarizmi's time, algebra was a practical system for solving all kinds of problems "in cases of inheritance, legacies, partition, lawsuits, and trade, and in all their dealings with one another, or where the measuring of lands, the digging of canals, geometrical computations, and other objects of various sorts and kinds are concerned."

al-jabr was about removing the negative terms from an equation, while al-muqabala meant "balancing" the values of an equation across an equals sign. Like this:

50 + 3x + x² = 29 + 10x

which can be simplified to just:

21 + x² = 7x

(Zap the 3x on the left-side by subtracting it from 10x on the right, then zap the 29 on the right-side by subtracting it from 50 on the left.)

More on al-Khwarizmi and al-jabr is available at MacTutor online and Wikipedia.

is a self directing entityD  categorized by MathematicsD  

2004-02-14 13:53:10.098658-06 Best permanent link

Actor/Observer Difference

When you screw-up you tend to blame it on an external cause, like the circumstances you were in, or the booze you had that night.

"I'm sorry I was rude, it's because I was in a hurry to catch a bus."

But when you watch someone else screw up you're more likely to blame it on their personality.

"He was rude because that's just the kind of person he is"

This is called the Actor/Observer Difference, where you (the actor) tend to blame your behavior on external factors (circumstances), but blame internal factors (personality/disposition) for the behavior of people you observe.

The difference is forged by how well you know yourself and the things that make you tick, versus what you know about other people. Since you have a constant awareness of the things that go on around you, there's a lot to chose from when it's time to blame something for your behavior. But unless you get to know somebody very well, or were paying attention to the things that might influence their behavior, you don't usually know what causes someone else to behave the way they do. So everybody else seems to be one-dimensional.

One phenomena that springs out of the Actor/Observer Difference is road rage. Since there aren't enough clues to tell you why other drivers behave the way they do, it forces your mind to view them as all a bunch of jerks.

is a behaviorD  categorized by PsychologyD  

2003-07-28 23:38:07.888182-05 Best permanent link

Arnett

Verb. To unintentionally boost an opposition's PR with a high-profile confession of opinion. To fuck up.

Noun. Verbal friendly fire.

is a activityD  categorized by WarD  categorized by JournalismD  

2003-03-31 13:48:05.966051-06 Best permanent link