Heracleum Sosnowskyi Manden.

Heracleum Sosnowskyi was discovered in 1772 and described as a separate species in 1944 by I. P. Mandenova. Its name is derived from the surname of a botanist studying Caucasian flora, Prof. D.I. Sosnowski. In the area of the Caucasus foothills, the plant reaches approximately 1-1,5 m in height, whereas in Poland its size is significantly larger, up to 3-3.5 m. Heracleum blooms from mid-June to the end of July. The flowers are arranged in umbels and last for 2-3 weeks. In Central Europe, the species colonizes mostly neglected green areas, ruins and riversides. Heracleum poses a serious threat to the human population due to its photoallergic properties, resulting from the presence of intensely toxic furanocoumarin in its sap. Furanocoumarins are found in small hairs that cover the leaves and stem, and are the components of the essential oil. They may penetrate the skin through the epithelial layer, posing a direct threat to human health. Contact with the plant, followed by sun exposure, may lead to the development of large blisters and symptoms of burns. Heracleum, in the event of consumption, is also harmful to farm animals, causing, among others, internal bleeding and diarrhea. Although the toxic properties of Heracleum have been known for many years, every summer people who had contact with the plant present at physicians of different medical specialties.

Immunotoxicity activity of natural furocoumarins from milky sap of Ficus carica L. against Aedes aegypti L.

Ficus carica L., its fruits are delicious and can be eaten by human. Its leaves are commonly used to cure hemorrhoid and clear away heart ache. The milky sap of F. carica have a significant toxic effect against early fourth-stage larvae of Aedes aegypti L with an lethal concentration (LC(50)) value of 10.2 µg/ml and an LC(90) value of 42.3 µg/ml. Two natural furocoumarins, 5-methoxypsoralen and 8-methoxypsoralen were isolated from the milky sap of F. carica. The LC(50) value of 5-methoxypsoralen and 8-methoxypsoralen were 9.4 and 56.3 µg/ml, respectively. The above indicates that major compounds may play a more important role in the toxicity of the milky sap of F. carica.

Therapeutic efficacy and safety of photochemically treated apheresis platelets processed with an optimized integrated set.

BACKGROUND: This multicenter, randomized, controlled, double-blind Phase III clinical study evaluated the therapeutic efficacy and safety of apheresis platelets (PLTs) photochemically treated (PCT) with amotosalen and ultraviolet A light (INTERCEPT Blood System, Baxter Healthcare Corp.) compared with conventional apheresis PLTs (reference). STUDY DESIGN AND METHODS: Forty-three patients with transfusion-dependent thrombocytopenia were randomly assigned to receive either PCT or reference PLT transfusions for up to 28 days. RESULTS: The mean 1- and 24-hour corrected count increments were lower in response to PCT PLTs (not significant). When analyzed by longitudinal regression analysis, the estimated effect of treatment on 1-hour PLT count was a decrease of 7.2 x 10(9) per L (p = 0.05) and on 24-hour PLT count a decrease of 7.4 x 10(9) per L (p = 0.04). Number, frequency, and dose of PLT transfusions; acute transfusion reactions; and adverse events were similar between the two groups. There was no transfusion-associated bacteremia. Four PCT patients experienced clinical refractoriness; however, only one exhibited lymphocytotoxicity assay seroconversion. Antibodies against potential amotosalen-related neoantigens were not detected. CONCLUSION: PCT PLTs provide effective and safe transfusion support for thrombocytopenic patients.

Systemic immunosuppression of cell-mediated immune reactions by a monofunctional psoralen plus ultraviolet A radiation.

Because of the undesirable side effects associated with the use of 8-methoxypsoralen and long-wave ultraviolet A (UVA) radiation in the treatment of skin disorders such as psoriasis, the use of monofunctional psoralens, which are less erythemogenic, less mutagenic, and generally non-phototoxic, has received considerable attention. Little is known, however, about the immunosuppressive properties of monofunctional psoralens. The purpose of this study was to examine the effect of parenteral administration of a monofunctional psoralen, angelicin, plus exposure to UVA radiation on the immune response. Injection of angelicin followed by exposure to UVA radiation significantly suppressed delayed-type hypersensitivity to alloantigen in a dose-dependent fashion. Similarly, the capacity of spleen cells from the angelicin and UVA-treated animals to proliferate to alloantigen was significantly suppressed. The suppression was specific for the alloantigen used to sensitize the angelicin and UVA-treated animals and was associated with the appearance of splenic antigen-specific suppressor T lymphocytes. These data demonstrate that the effect of systemic administration of a monofunctional psoralen followed by UVA exposure on the immune response is similar to that seen following the injection of bifunctional psoralens. These findings also suggest that the severe skin phototoxicity associated with the use of a bifunctional psoralen and UVA radiation is not necessary for the induction of systemic immuno-suppression. Furthermore, the induction of systemic antigen-specific immunosuppression by angelicin plus UVA, without overt skin phototoxicity, suggests the possibility of using this and related compounds to specifically inhibit unwanted immune reactions.

Antibodies against DNA-psoralen crosslink recognize unique conformation.

The DNA-psoralen crosslink induced precipitating antibodies in rabbits with a titer of 1:102,400 by direct binding ELISA. The antiserum showed considerable binding with Z-DNA and calf thymus DNA brominated under high salt concentration which has been shown to attain Z-/analogous conformation. Inhibition experiments substantiated the results of direct binding assay. However, the affinity purified IgG showed high degree of specificity for the immunogen and did not recognize nDNA, Z-DNA and brominated DNA as inhibitor. Poly(dG.dC).poly(dG.dC)-psoralen photoadduct was found to be inhibitory. These results indicate that the antibodies are probably recognizing the unique conformation at the site of psoralen crosslinking. The DNA-psoralen crosslink showed significant binding with SLE sera known to have high levels of anti-native DNA antibodies. Affinity purified SLE-IgG in a competition assay pointed out the autoantibody recognition of altered conformation of DNA-psoralen crosslink.

Accidental induction of photocontact allergy to Heracleum laciniatum.

Photocontact allergy to psoralens in Heracleum laciniatum occurred in two persons volunteering for investigations into phototoxicity of plant homogenates and purified psoralens. Photoallergy was noted following the fifth exposure in case 1, and the sixth in case 2. Testing with diluted solutions demonstrated allergy to sphondin, isobergapten and pimpinellin.