Medical research

Some skin cancers may start in hair follicles

Some of the most deadly skin cancers may start in stem cells that lend color to hair, and originate in hair follicles rather than in skin layers, a new study finds.

Medical research

Lymphatic system found to play key role in hair regeneration

Given the amount of wear and tear it's subjected to on a daily basis, the skin has a phenomenal ability to replenish itself. Spread throughout it are small reservoirs of stem cells, nested within supportive microenvironments ...

Medical research

New technique may reveal the health of human hair follicles

A variety of factors can stop hair from forming and growing properly, leading to hair diseases and baldness. A new method developed by investigators at Massachusetts General Hospital (MGH) recently examines the activity of ...

Medical research

Biomarker for schizophrenia can be detected in human hair

Working with model mice, postmortem human brains, and people with schizophrenia, researchers at the RIKEN Center for Brain Science in Japan have discovered that a subtype of schizophrenia is related to abnormally high levels ...

Health

What to do if you have a bad reaction to cosmetics

(HealthDay)—One consequence of the government's limited role in regulating cosmetics is that questionable products may stay on store shelves and e-commerce sites despite complaints. Even when consumers report problems, ...

Health

Air pollution linked to hair loss, new research reveals

Research presented today at the 28th EADV Congress in Madrid shows, for the first time, that exposure to common air pollutants known as particulate matter (PM) is linked to hair loss in humans.

Oncology & Cancer

Engineered T cells may be harnessed to kill solid tumor cells

There is now a multitude of therapies to treat cancer, from chemotherapy and radiation to immunotherapy and small molecule inhibitors. Chemotherapy is still the most widely used cancer treatment, but chemotherapy attacks ...

Medical research

Outer hair cells regulate ear's sensitivity to sound

The ear's tiny outer hair cells adjust the sensitivity of neighbouring inner hair cells to sound levels rather than acting like an amplifier, suggests a new study published today in eLife.

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Hair

Hair is a protein filament that grows through the epidermis from follicles deep within the dermis. The fine, soft hair found on many nonhuman mammals is typically called fur; wool is the characteristically curly hair found on sheep and goats. Found exclusively in mammals, hair is one of the defining characteristics of the mammalian class. Although other non-mammals, especially insects, show filamentous outgrowths, these are not considered "hair" in the scientific sense. So-called "hairs" (trichomes) are also found on plants. The projections on arthropods such as insects and spiders are actually insect bristles, composed of a polysaccharide called chitin. There are varieties of cats, dogs, and mice bred to have little or no visible fur. In some species, hair is absent at certain stages of life. The main component of hair fiber is keratin.

The hair can be divided into three parts length-wise, (1) the bulb, a swelling at the base which originates from the dermis, (2) the root, which is the hair lying beneath the skin surface, and (3) the shaft, which is the hair above the skin surface. In cross-section, there are also three parts, (1) the medulla, an area in the core which contains loose cells and airspaces (2) the cortex, which contains densely packed keratin and (3) the cuticle, which is a single layer of cells arranged like roof shingles.

This text uses material from Wikipedia, licensed under CC BY-SA