|[Note Guidelines] Photographer's Note|
|Digitalis sp. - a very beautiful flower but at the same time an extremely lethal poison. The plants contains alkaloids that interfere with heart action. It may cure and is used in many medicines but also may kill...|
Digitalis is a genus of about 20 species of herbaceous biennials, perennials and shrubs that was traditionally placed in the figwort family Scrophulariaceae. Due to new genetic research, it has now been placed in the much enlarged family Plantaginaceae.
The term digitalis is also used for preparations containing cardiac glycosides, particularly digoxin, extracted from plants of this genus.
The members of this genus are known in English as foxgloves. They are native to Europe, northwest Africa and west and central Asia. The scientific name means "finger", and refers to the ease which a flower of Digitalis purpurea can be fitted over a human fingertip. "Foxglove" has a similar origin, seen as a suitable glove for a fox paw.
A group of pharmacologically active compounds are extracted mostly from the leaves of the second year's growth, and in pure form are referred to by common chemical names such as digitoxin or digoxin, or by brand names such as Lanoxin, or Purgoxin.
Digitalis works by inhibiting sodium-potassium ATPase, which increases intracellular calcium. The increased intracellular calcium gives a positive inotropic effect. It also has a vagal effect on the parasympathetic nervous system, and as such is used in reentrant cardiac arrhythmias and to slow the ventricular rate during atrial fibrillation. The dependence on the vagal effect means that digitalis is not effective when a patient has a high sympathetic nervous system drive, which is the case with acutely ill persons.
Digitalis toxicity (Digitalis intoxication) results from an overdose of digitalis and can result in jaundiced (yellow) vision and the appearance of blurred outlines (halos), as well as bradycardia in extreme cases. Because a frequent side effect of digitalis is reduction of appetite, some individuals have abused the drug as a weight loss aid.
Digitalis is a classic example of a drug derived from a plant formerly used by folklorists and herbalists: herbalists have largely abandoned its use because of its narrow therapeutic index and the difficulty of determining the amount of active drug in herbal preparations. Once the usefulness of digitalis in regulating pulse was understood, it was employed for a variety of purposes, including the treatment of epilepsy and other seizure disorders, now considered inappropriate.
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Wow, beautiful flower. Your focus is sharp and clear on the center flowers and the colors and detail are great. Thanks for sharing!
- [2005-07-29 0:42]
Nice shot. I like the DOF used it adds a bit of interest having some of the floweretts out of focus.
- [2005-07-29 3:27]
Beautiful and interesting shot for this superb Digitalis ! Composition, colors, details and sharpness are very good ! Thanks for sharing Michal.
- [2005-07-29 5:05]
Beautifull indeed! I love shapes and velvet look of petals [or flowers ;-)]. Great colours and composition with detailed, red 'veins' on flowers. I like its latin name ;-) Very suitable for digital age ;-) In English it also has got interesting name - Foxglove.
- [2005-07-29 5:21]
This Digitalis is an unusual colour. I love these foxgloves and this is the first time I've seen one this colour or one with those shaped flowers. Good capture, nice and sharp and great details. Well done, thank you Michal.
You show us this flowers very nicely and closely. Wonderful colours and great composition. BG is going well with the shot.
As of my knowledge, this is Digitalis ferruginea. You did a wonderful photo.
- [2006-11-09 16:18]
Fantastic picture of this marvellous specie. Congratulations
I had photographed a very similar type of a flower;
have never posted it because I could not name it.
This is a facsinating note along with this subject.
Excellent clarity, focusing, composition & its
Best regards, Mario from Canada.
- [2007-01-28 14:31]
I really like tight framing as is the case here. Great texture, color and sharpness.