Immunology

Asthma answer may not be steroids for women

For women depending on steroids to treat severe asthma, their body's estrogen may not only be preventing the treatment from working effectively, but making the asthma worse, according to a recent Western study.

Health

The hazards of living on the right side of a time zone border

The sun both rises and sets later in the western parts of time zones, by about an hour at the extremes. If sunrise in Nashville, Tennessee is 6:30 a.m., it's about 7:30 a.m. in Amarillo, Texas. Similarly, if sunset in Nashville ...

Obstetrics & gynaecology

Antibiotics may treat endometriosis

Researchers at Washington University School of Medicine in St. Louis have found, in mice, that treatment with an antibiotic reduces the size of lesions caused by endometriosis.

Medical research

New discovery could lead to improved blood sugar level control

Many diabetes patients do not only have problems with their insulin, but also with the release of the hormone glucagon. Researchers at Uppsala University have now discovered a regulation mechanism which could provide an opportunity ...

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Hormone

Hormones (from Greek ὁρμή - "impetus") are chemicals released by cells that affect cells in other parts of the body. Only a small amount of hormone is required to alter cell metabolism. It is essentially a chemical messenger that transports a signal from one cell to another. All multicellular organisms produce hormones; plant hormones are also called phytohormones. Hormones in animals are often transported in the blood. Cells respond to a hormone when they express a specific receptor for that hormone. The hormone binds to the receptor protein, resulting in the activation of a signal transduction mechanism that ultimately leads to cell type-specific responses.

Endocrine hormone molecules are secreted (released) directly into the bloodstream, while exocrine hormones (or ectohormones) are secreted directly into a duct, and from the duct they either flow into the bloodstream or they flow from cell to cell by diffusion in a process known as paracrine signalling.

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