Wednesday, September 24, 2008

Sales of U.S. Beef Soaring

Just a few months ago, the streets of downtown Seoul were occupied by demonstrators protesting against the import U.S. beef. According to a number of polls, an absolute majority of people said they would not eat U.S. beef because they feel it is unsafe. But just three months after imports resumed on June 26 under new quarantine requirements, U.S. beef jumped to second in terms of market share in imported beef, after Australian product. Sales rose sharply just before the Chuseok or Korean Thanksgiving holiday; between Sept. 1 and 10, it even topped the imported beef market chart with a 48 percent market share.

◆ Chuseok Boost

Over 11,300 tons of U.S. beef have now passed the quarantine control and hit the shelves in Korean stores, 3,688 tons from Sep. 1 to 10. During that period, the market share of U.S. beef was 48.1 percent, jumping from 23.9 percent in July and 24.3 percent in August. From August, not only frozen beef but also refrigerated beef was imported.

◆ Young Skeptics

A considerable share of groundless rumors about mad cow disease is gone, and the website of the People’s Association for Measures Against Mad Cow Disease, which organized the protests, is virtually defunct. One online community on portal site Naver that saw more than 100 posts a day at the height of the furor, there was only one message on Monday. However, U.S. beef is still unpopular among young mothers in their 20s and 30s. A staffer in a butcher’s shop in Uijeongbu, Gyeonggi Province, said, “While there are a lot of middle-aged housewives buying U.S. beef, there isn’t much demand from young mothers.

◆ Superstores & Malls Think Again

Superstores and department stores that have not started selling U.S. beef for fear it would spark indignation among customers are now reconsidering. Some are in the process of deciding when to start sales. A staffer with a superstore said, “We get a lot of call enquires asking us when we’re going to start selling U.S. beef from housewives in their forties and fifties. We assume the fears of mad cow disease have gone and are therefore deciding on when to start selling U.S. beef.”

Wednesday, September 17, 2008


Enzymes are biomolecules that catalyze (i.e. increase the rates of) chemical reactions. Almost all enzymes are proteins. In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, the products. Almost all processes in a biological cell need enzymes in order to occur at significant rates. Since enzymes are extremely selective for their substrates and speed up only a few reactions from among many possibilities, the set of enzymes made in a cell determines which metabolic pathways occur in that cell.

Like all catalysts, enzymes work by lowering the activation energy (Ea or ΔG‡) for a reaction, thus dramatically increasing the rate of the reaction. Most enzyme reaction rates are millions of times faster than those of comparable un-catalyzed reactions. As with all catalysts, enzymes are not consumed by the reactions they catalyze, nor do they alter the equilibrium of these reactions. However, enzymes do differ from most other catalysts by being much more specific. Enzymes are known to catalyze about 4,000 biochemical reactions. A few RNA molecules called ribozymes catalyze reactions, with an important example being some parts of the ribosome. Synthetic molecules called artificial enzymes also display enzyme-like catalysis.

Wednesday, September 10, 2008

Genetic testing

Genetic testing involves the direct examination of the DNA molecule itself. A scientist scans a patient’s DNA sample for mutated sequences.

There are two major types of gene tests. In the first type, a researcher may design short pieces of DNA (“probes”) whose sequences are complementary to the mutated sequences. These probes will seek their complement among the base pairs of an individual’s genome. If the mutated sequence is present in the patient’s genome, the probe will bind to it and flag the mutation. In the second type, a researcher may conduct the gene test by comparing the sequence of DNA bases in a patient’s gene to disease in healthy individuals or their progeny.
Genetic testing is now used for:

* Determining sex
* Carrier screening, or the identification of unaffected individuals who carry one copy of a gene for a disease that requires two copies for the disease to manifest
* Prenatal diagnostic screening
* Newborn screening
* Presymptomatic testing for predicting adult-onset disorders
* Presymptomatic testing for estimating the risk of developing adult-onset cancers
* Confirmational diagnosis of symptomatic individuals
* Forensic/identity testing