People, skin color

Dark skin is a commonly used phrase to describe people of color. Other terms used to describe darker skin types include ethnic skin, brown skin, and pigmented skin. The unifying feature represented is pigmented skin (i.e., shades of tan, olive, brown, and black). Such individuals are often classified as Fitzpatrick s skin types IV through VI. These individuals represent many of the faces of North America, South America, Africa, the Caribbean, Asia, Malaysia, and Australia. 

Traveling around the state installing his machinery, Rillieux had to stay on slave-operated plantations. Like many free people of color, Rillieux may have regarded himself as the equal of the white ruling class, far above dark-skinned slaves. But in the antebellum South, Rillieux could not stay in the plantations mansions. Rumor had it that he stayed in slave quarters, but a firsthand observer reported that on Benjamin s plantation Rillieux was given a special house and slaves to serve him. 

What does DNA analysis tell us about race Most investigators conclude that there is only one human race with no detectable boundaries between the group commonly referred to as races.334-336 As Paabo put it, "in terms of the variation at most loci, we all seem to be Africans, either living on that continent or in recent exile."328 The differences in skin color seem to reflect adaptation to the environment in which people live.336a Variations in the level of melanocyte-stimulating hormone receptor, one regulator of skin color (Box 25-A), are especially high in Africans.328... 

At a time not too long ago, ethnic groups, or human races were defined by geography and appearence, most often simply by skin color, sometimes additionally by language. These factors are still considered by many people as main indicators, but at the present time, the scientifically defining factors are genetic differences between populations. 

Because some lasers can temporarily or permanently discolor the skin, a dark-skinned patient should make sure that his surgeon has successfully performed laser procedures on people of color. 

The people in Turkey who ate bread contaminated with hexachlorobenzene suffered from a liver disease called porphyria cutanea tarda. This disease can cause red-colored urine, skin sores, changes in skin color, arthritis, and problems of the liver, nervous system, and stomach. 

That race is not a biological construct rests on a number of considerations (Williams, 1997). First, the concept of race predates biological attempts at classification people have always been classified by their skin color and other external features. Second, the phenotypic expression used to classify an individual, like skin color, does not correlate with genetic variability. It is often stated that there is more variability within races than between races. In other words, two individuals from any two races will have about as much genetic variability as any two individuals from within the same... 

Although the reader may intuitively understand what race is and how to measure it, as it is used ubiquitously throughout the medical literature, there are clear measurement and conceptual issues that must first be resolved before it can be used in an analysis. One problem with race is that many people believe they can define it, usually based on a person s skin color. It s crazy to believe that a person s skin color is a predictor for complex physiological differences, yet this is what scientists do. Further, racial classification is a categorical decision based on a continuous scale. Skin color varies from light to dark. Where is the break-point and who decides Clearly, race is a surrogate for some other factor socioeconomic, dietary, genetic, etc. There must be a better way to measure such differences. 

The digital camera was the best device compared to the spectrophotometer and the scanner in reproducing facial skin color. It is indicated to record dark skin people. The scanner results of skin color reproduction were fair in capturing light skin tones. 

These techniques have been used in forensic science to identify murder victims. For example, in Ireland, the headless body of a male 35-40 years old was discovered. Skin color and physical characteristics suggested that he was of African/Afro-Caribbean or African-American ancestry. Stable isotope ratios in his hair, bones, and teeth were compared with those of people whose geographic origin and life history were known. From the hair, it was established that he had lived in Ireland for at least 9-12 months before his death. The femur was then tested while ribs remodel in about 10 years, long bones such as the femur take about 20 years. The inner part of the bone reflects the most recent history, and the 0/ 0 profile corresponded to local drinking water. However, the outer, older part of the femur suggested water with a 8 value of... 

Finally, glycolic acid is a member of the alpha-hydroxy acid family, which provides an important adjunctive therapy in a variety of skin disorders. It is widely used in chemical peels in a variety of concentrations, ranging from 20 to 70%. People of almost any skin type and color are candidates and almost any area of the body can be peeled. 

Iodine is the least reactive of the elements in the halogen group 17. Most people associate iodine with the dark-brown color of the tincture of iodine used as an antiseptic for minor skin abrasions and cuts. A tincture is a 50% solution of iodine in alcohol. Although it is still used, iodine is no longer the antibiotic of choice for small skin wounds. Since iodine is a poison that kills bacteria, iodine tablets are often used by campers and others to purify water that is taken from outdoor streams. 

DNB and 1,3,5-TNB are suspected to cause similar health effects. Exposure to high concentrations of 1,3-DNB can reduce the ability of blood to carry oxygen and can cause your skin to become bluish in color. If you are exposed to 1,3-DNB for a long time, you can develop a reduction (or loss) in the number of red blood cells (anemia). Other symptoms of 1,3-DNB exposure include headache, nausea, and dizziness. We do not know if there are any long-term health effects of exposure to 1,3-DNB or 1,3,5-TNB in people. We also do not know if 1,3-DNB or 1,3,5-TNB causes birth defects or cancer in people. 

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