Hypericum is a genus of about 400 species of flowering plants in the family Clusiaceae, formerly often treated separately in their own family the Hypericaceae. The genus has a nearly world-wide distribution, missing only from tropical lowlands, deserts and arctic regions.
The species vary from small annual or perennial herbaceous plants 5-10 cm tall, to shrubs and small trees up to 12 m tall. The leaves are opposite, simple oval, 1-8 cm long, either deciduous or evergreen. The flowers vary from pale to dark yellow, and from 0.5-6 cm diameter, with five (rarely four) petals. The fruit is usually a dry capsule which splits to release the numerous small seeds; in some species it is fleshy and berry-like.
All members of the genus may be referred to as "St. John's worts" or St.John's-worts, though they are also commonly just called Hypericums; other names include Rose of Sharon and Tutsan. Some species are used as ornamental plants and have large, showy flowers.
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Materia Medica :: St. John's Wort
PLoS Medicine: New ArticlesPLoS Medicine Issue Image | Vol. 6(6) June 2009 Tue, 30 Jun 2009 07:00:00 -0000
Clean water should be recognized as a human right.
At the March 2009 United Nations meetings coinciding with the World Water Forum, a declaration that would recognize water as a basic human right was defeated. In this month's Editorial, the PLoS Medicine Editors argue that access to clean water should be declared a basic human right for three reasons. First, access to clean water can substantially reduce the global burden of disease caused by water-borne infections. Second, the privatization of water—as witnessed in Bolivia, Ghana, and other countries—has not effectively served the poor, who suffer the most from lack of access to clean water. Third, the prospect of global water scarcity—exacerbated by climate change, industrial pollution, and population growth—means that no country is immune to a water crisis.Image Credit: Rudhach at flickr.com
Seasonal Hunger: A Neglected Problem with Proven SolutionsBapu Vaitla et al. Tue, 30 Jun 2009 07:00:00 -0000
Clean Water Should Be Recognized as a Human Right Tue, 30 Jun 2009 07:00:00 -0000
Can We âHedgeâ against the Development of Antiviral Resistance among Pandemic Influenza Viruses?David K. Shay et al. Tue, 30 Jun 2009 07:00:00 -0000
David K. Shay and Benjamin Ridenhour discuss a modeling study predicting that stockpiling a secondary antiviral for use early in a flu pandemic can forestall resistance to the primary stockpiled drug.
Pralidoxime in Acute Organophosphorus Insecticide PoisoningâA Randomised Controlled TrialMichael Eddleston et al. Tue, 30 Jun 2009 07:00:00 -0000
In a randomized controlled trial of individuals who had taken organophosphorus insecticides, Michael Eddleston and colleagues find that there is no evidence that the addition of the antidote pralidoxime offers benefit over atropine and supportive care.
What Is the Optimal Therapy for Patients with H5N1 Influenza?Nicholas J. White et al. Tue, 23 Jun 2009 07:00:00 -0000
Nicholas White discusses optimal dosing of oseltamivir, Robert Webster and Elena Govorkova discuss combination antiviral therapy, and Timothy Uyeki discusses clinical care of patients with H5N1.
EurekAlert! - BiologyStudy identifies how tamoxifen stimulates uterine cell growth and cancer Thu, 02 Jul 2009 00:00:00 -0400
(University of California - San Francisco) University of California - San Francisco researchers have identified a new "feed-forward" pathway linking estrogen receptors in the membrane of the uterus to a process that increases local estrogen levels and promotes cell growth.
'Genetic arms race' between bacteria, viruses subject of stimulus grant Thu, 02 Jul 2009 00:00:00 -0400
(Michigan State University) The oceans teem with microscopic bacteria that produce much of Earth's oxygen as they absorb carbon dioxide greenhouse gas. But fast-mutating viruses also populate the seas, attacking marine bacteria in an ages-old evolutionary arms race. A Michigan State University researcher will probe that ancient dynamic against the backdrop of environmental and climate change, and the pivotal role played by aquatic bacteria in maintaining the Earth's biological balance.
Learning from locusts Thu, 02 Jul 2009 00:00:00 -0400
(Queen's University) A similarity in brain disturbance between insects and people suffering from migraines, stroke and epilepsy points the way toward new drug therapies to address these conditions.
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Hypericum calycinum - image
Hypericum crux-andreae - St. Peterswort.
Meta Description: [ A PLANTS profile of Hypericum crux-andreae (St. Peterswort) from the USDA PLANTS database ]
Hypericum hypericoides ssp. hypericoides - St. Andrew's cross.
Meta Description: [ A PLANTS profile of Hypericum hypericoides ssp. hypericoides (St. Andrew's cross) from the USDA PLANTS database ]
Hypericum perforatum - Description of Common St. Johnswort.
Hypericum perforatum - Photo and profile of common St. Johnswort, with particular focus on its status as a noxious weed in parts of the U.S.
Meta Description: [ A PLANTS profile of Hypericum perforatum (common St. Johnswort) from the USDA PLANTS database ]