1,468 research outputs found
Utility and limits of noninvasive methods in dermatology
No full textThe approach to medical diagnosis has undergone profound changes in recent years owing to the advent of instrumental diagnosis, which has replaced traditional clinical methods based on the medical history and objective signs. Many medical and surgical specialties now use instruments that are able to provide a more accurate diagnosis via noninvasive methods. This has led to the birth of super-specialized sectors which, within each discipline, promote knowledge and research in the respective fields of interest.
Dermatology has probably been the last discipline to embrace instrumental diagnosis. Indeed, the advent of bioengineering caught many dermatologists off-guard, bewildered by the many proposals coming from the medical supply industry and distrustful of machines whose practical utility was not always clear. This distrust may have ancestral origins, ingrained in the very essence of dermatology, which is a typical morphological discipline based on clinical aspects appreciable through sensory perceptions. During their specialist training, dermatologists learn to observe, recognize and classify lesions in order to identify the stereotypes that provide them with the diagnosis. Convinced of their perceptive superiority over any machine, they have not felt the need to develop suitable instruments to aid their objective examination. This methodological approach has led many dermatologists to consider instruments completely useless or even as enemies to combat, in that they are dangerous rivals of clinical experience. This type of attitude is obviously erroneous: although it is true that instrumental methods cannot replace the experience, sensitivity and intuition of the clinician, it is also true that they can be a valid complement to clinical methodology.
In fact, this prejudice has been disappearing for some years now and, additionally, dermatology has begun to employ instrumental semeiotics. Increasingly sophisticated machines that are able to explore the skin in a noninvasive manner can now provide biophysical measurements of the integumentary apparatus; these measurements can be considered parametric data of analogically appreciable signs. This has given rise to bioengineering of the skin, which in just a few years has led to the constitution of an autonomous and expanding sector.
The purpose of this editorial is to provide a panorama of noninvasive diagnostic methods in dermatology in an attempt to identify the instruments that are truly useful in current clinical practice, those whose use is important in specialized sectors, such as dermopharmacology and dermocosmetology, and those that have only experimental relevanc
Topically Applied Lycopene and Antioxidant Capacity
No full textVarious antioxidant substances have a protective effect on the skin when applied in suitable formulations. Natural lycopene (extracted from tomato), incorporated in an oil/water emulsion at a concentration of 0.03% and applied to the skin 30 min before ultraviolet exposure, decreased the erythema induced by UV radiation. Lycopene was more effective when associated with a-tocopherol palmitate and ascorbic acid, at concentrations of 0.5% and 1%, respectively. Since lycopene does not screen UV radiation, its protective ability is due to antioxidant activity. The potentiation of its effectiveness by vitamins E and C can probably be attributed to an interaction between the three substances in the cascade of events leading to the antiradical effect. As proposed for b-carotene, lycopene may act by repairing the tocopherol radical, after which it is repaired by the ascorbic acid. The efficiency of the system could be related to the different affinities (lipophilic or hydrophilic) of the components of this triple association. Because of its characteristics, lycopene is particularly suitable for topical application in sunscreens or in any preparation designed to prevent or reduce the harmful effects of oxidative stimuli
In vivo and in vitro evaluation of phytic acid as topical antioxidant
No full textThe use of locally applied antioxidants has been shown as an effective approach for the skin photo-protection. In a previous investigation we have demonstrated that phytic acid (PA), a component of most cereal grains and seeds, is able to reduce the erythemal response to UV-exposure when applied 30 minutes before UV-radiation. PA was used at 0.5 % concentration in a O/W emulsion containing also inositol at 2.0 % concentration. Before the test and 24 and 48 h after irradiation the extent of the reaction was evaluated with visual scoring as well as with instrumental measurement of skin redness,TEWL and hydration. In this study we have evaluated the ability of PA to protect human keratinocytes cultures against UV exposure. PA extracted from the rice bran was used at 100 μM. The experiments were performed also on ascorbic acid
at the same concentration. Human HaCaT keratinocytes were grown in 3,5 cm2 plates containing complete medium (DMEM with 10% fetal calf serum). Thirty minutes before UV radiation, medium was removed and replaced by PBS with or without the antioxidants. The light source was a 150-Watt xenon arc solar simulator. Series of cultures were irradiated with scalar UV-doses ranging from 11,56 to 92,48 mJ/cm2. After irradiation PBS solution with or without antioxidants was removed and replaced with fresh medium. The antioxidant activity was evaluated by MTT
assay after 24 hrs. The solutions containing the active ingredients demonstrated a protective ability stronger than that of the controls. Particularly PA showed an ability to protect the keratinocytes against UV damage more pronounced than vitamin C. Our investigation has proved
that phytic acid is able to protect human keratinocytes against UV radiation. This means that epidermal cells are involved in the PA-mediated photoprotection in vivo and represents a fur-ther support for the use of PA as topical photoprotective agent
Emergency Management of Purpura and vasculitis, Including Purpura Fulminans
No full textSystemic vasculitides can frequently evolve into emergency
conditions and sometimes present a critical situation
from their onset. The latter occurs most frequently in PF,
whereas progress to a critical situation is observed in HSP,
WG, CSS, PAN, MPA, and KD. The management of such
patients may require the dermatologist because the correct
interpretation of cutaneous lesions, an integral part of the
clinical pattern, can provide substantial help in identifying
the nature and phase of the disease. Dermatological assistance
may be essential in the treatment of lesions largely
involving the skin
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