Health threat associated with Caucasian giant hogweeds: awareness among doctors and general public in Poland

Context: The Caucasian giant hogweeds (Heracleum sosnowskyi and H. mantegazzianum) are aggressive invaders successfully spreading across different parts of Europe. Their sap containing linear furanocoumarins can lead to a persisting cutaneous dermatitis and massive skin necrosis.

Objective: We aimed to assess the awareness of the giant hogweeds’ threat among physicians and general public in Poland.

Methods: The level of awareness was assessed using a short questionnaire given to different groups of physicians: dermatologists (DMs), general practitioners (GPs) and occupational practitioners (OPs). An independent questionnaire was also addressed to the general public.

Results: Among the surveyed physician groups, DMs were the best informed, while OPs were the worst informed on health threats associated with the giant hogweeds and treatment methods. Most frequently, application of topical corticosteroids was indicated as a successful method of treatment following the exposure to hogweeds. In the general public, awareness was relatively low with only 57.7% of the surveyed having ever heard about these plants. TV, press and Internet were among the most frequent sources of information in this regard.

Conclusions: Public and medical attention needs to be raised as to the threats associated with giant hogweeds, particularly in countries that are highly infested with these plants.     

Sunlight and ultraviolet radiation—pertinent retinal implications and current management

Unprotected and prolonged exposure to ultraviolet (UV) light from sunlight, lasers, and arc welding leads to outer retinal damage. The photoreceptors and retinal pigment epithelium located in the posterior pole are particularly susceptible to this radiation. Classically known as solar retinopathy, this disorder frequently affects young individuals who have clear lenses and a propensity toward observing solar eclipses. Various imaging techniques aid the clinician in diagnosis, even if patients cannot recall an exposure event. By far the most utilized technique is optical coherence tomography that, in tandem with fluorescein angiography, and fundus autofluorescence, is crucial in ruling out other conditions. Fortunately, the prognosis of acute UV retinopathy is favorable, as most cases fully recover; however, a significant percentage of patients suffer from chronic sequelae: reduced acuity and lifelong central/paracentral scotomas. Thus, education toward understanding UV exposure risks, coupled with either abstinence or proper eye protection, is critical in preventing macular damage. We outline the various etiologies responsible for UV-induced retinopathy, describe the limited treatments available, and provide recommendations to minimize the potential devastating ophthalmic consequences as our society increases its reliance on UV-emitting technology and further engages in solar eclipse viewing.     

In vitro evaluation of betamethasone esters for phototoxic potential

The phototoxicity of Betamethasone valerate and betamethasone dipropionate has been investigated on irradiation in the wavelength range of 300–400?nm, using some basic in vitro phototoxicity tests. Both esters cause photohemolysis of mouse red blood cells and photoperoxidation of linoleic acid. The photoproducts of both esters have also been found to be phototoxic. The toxicity of these photoproducts increases with further irradiation; however, they exhibit toxicity, even in the dark. The efficient inhibition of photohemolysis by the well-known free radical scavengers, such as butylhydroxyanisole and reduced glutathione, and minor inhibition by singlet-oxygen quenchers, such as sodium azide, suggests that cellular damage is mainly mediated by free radicals whereas singlet oxygen plays a minor role.     

Phototoxicity due to Cachrys libanotis

After classification and identification of the plant, the alcoholic extract of Cachrys libanotis L. was analysed in order to identify the phototoxic agents. The substances responsible for photodermatitis were found to be 4 furocoumarins, of which 3 have been clearly identified, namely 5-methoxy-, 8-methoxy-and 5,8-dmiethoxypsoralen. The structure of a 4th compound was not completely defined.     

Blue-blocking IOLs Decrease Photoreception Without Providing Significant Photoprotection

Violet and blue light are responsible for 45% of scotopic, 67% of melanopsin, 83% of human circadian (melatonin suppression) and 94% of S-cone photoreception in pseudophakic eyes (isoilluminance source). Yellow chromophores in blue-blocking intraocular lenses (IOLs) eliminate between 43 and 57% of violet and blue light between 400 and 500 nm, depending on their dioptric power. This restriction adversely affects pseudophakic photopic luminance contrast, photopic S-cone foveal threshold, mesopic contrast acuity, scotopic short-wavelength sensitivity and circadian photoreception. Yellow IOL chromophores provide no tangible clinical benefits in exchange for the photoreception losses they cause. They fail to decrease disability glare or improve contrast sensitivity. Most epidemiological evidence shows that environmental light exposure and cataract surgery are not significant risk factors for the progression of age-related macular degeneration (AMD). Thus, the use of blue-blocking IOLs is not evidence-based medicine. Most AMD occurs in phakic adults over 60 years of age, despite crystalline lens photoprotection far greater than that of blue-blocking IOLs. Therefore, if light does play some role in the pathogenesis of AMD, then 1) senescent crystalline lenses do not prevent it, so neither can blue-blocking IOLs that offer far less photoprotection, and 2) all pseudophakes should wear sunglasses in bright environments. Pseudophakes have the freedom to remove their sunglasses for optimal photoreception whenever they choose to do so, provided that they are not encumbered permanently by yellow IOL chromophores. In essence, yellow chromophores are placebos for prevention of AMD that permanently restrict a pseudophake's dim light and circadian photoreception at ages when they are needed most. If yellow IOLs had been the standard of care, then colorless UV-blocking IOLs could be advocated now as “premium” IOLs because they offer dim light and circadian photoreception roughly 15-20 years more youthful than blue-blocking IOLs.     

Subcellular Phototoxicity of Photofrin-II and Lutetium Texaphyrin in Cells In Vitro

. Three cell types including bovine pulmonary artery endothelium cells (CPAE), rat kangaroo kidney cells (PTK₂), and human larynx epidermoid carcinoma cells (Hep-2) were used to study subcellular localisation and phototoxicity of Photofrin-II and lutetium texaphyrin (Lu Tex). Cells were examined for fluorescence after administration of the photosensitisers. Subcellular regions were exposed with a laser microbeam system that used an argon ion laser pumped dye laser generating a 630 nm for Photofrin-II and 730 nm for Lu Tex. Fluorescence detection suggests that the Photofrin-II is bound primarily to the mitochondria with some diffuse fluorescence in the rest of the cytoplasm. The fluorescence in Lu Tex treated cells appears to be localised to the lysosomes. The percentage of damaged cells following light exposure to the different subcellular regions after Photofrin-II or Lu Tex treatment demonstrates that the nuclear region was the most sensitive target followed by the perinuclear region and peripheral cytoplasm region. Paper received 27 January 1998; accepted after revision 21 August 1998.     

Reappraising the phototoxicity of tretinoin: a report of four controlled clinical trials

Background: Retinoids are photoreactive molecules found in skin and retinal tissue. The use of retinoids in pharmacologic doses, applied topically, raises the potential of phototoxicities. Recent review articles and current US drug labeling indicate that tretinoin is a phototoxin. In developing a new formulation of topical all- trans -retinoic acid (tretinoin), formal testing of dermal photoreactions was therefore undertaken.
Methods: Four prospective, randomized, and controlled trials were carried out in healthy volunteers at two independent research facilities. Two trials examined phototoxicity following 24 h of drug exposure under occlusion (combined n =51), and two examined photoallergenicity following a 3-week, six dose induction phase (combined n =72) followed by challenge.
Results: No phototoxic or photoallergic reactions occurred with tretinoin 0.05% in a new gel formulation.
Conclusion: The findings in these studies are consistent with previous studies of tretinoin in various formulations, and support the conclusion that tretinoin appears to be neither phototoxic nor photoallergenic in vivo .