In a study in mice, Johns Hopkins Medicine researchers have found a molecular switch that turns off the animal's ability to repair damaged cells in the inner ear. The findings shed light on regenerative abilities that are ...
Nov 25, 2020
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(HealthDay)—Add stress-related hair loss to the many problems caused by the coronavirus pandemic.
Nov 20, 2020
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In the last decade, concerns have emerged around finasteride, a drug used for treating male-pattern baldness and prostate gland enlargement. Organizations such as the Post-Finasteride Syndrome Foundation have warned about ...
Nov 11, 2020
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A novel method to sample earwax could be a cheap and effective way to measure the hormone cortisol, according to a study led by researchers at UCL and King's College London.
Nov 03, 2020
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An international team of researchers has found that patients with acne have lower levels of expression of the protein GATA6 in their skin. In their paper published in the journal Nature Communications, the group describes ...
Vanderbilt University researchers have reported the counterintuitive discovery that certain chemotherapeutic agents used to treat tumors can have the opposite effect of tissue overgrowth in normal, intact mammary glands, ...
Oct 16, 2020
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Julie Sciascia-Van Horn was hospitalized with COVID-19 in early April, suffering from some of the typical flu-like symptoms associated with the virus since its discovery: fever, severe cough and shortness of breath.
Oct 08, 2020
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A team of researchers from Cologne and Helsinki has discovered a mechanism that prevents hair loss: hair follicle stem cells, essential for hair to regrow, can prolong their life by switching their metabolic state in response ...
Sep 28, 2020
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For people who suffer from asthma, wildfire smoke is more hazardous than other types of air pollution, according to a new study from the Desert Research Institute (DRI), the Renown Institute for Health Innovation (Renown ...
Sep 23, 2020
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Researchers at the University of Maryland School of Medicine (UMSOM) have conducted a study that has determined the role that a critical protein plays in the development of hair cells. These hair cells are vital for hearing. ...
Sep 11, 2020
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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.
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