Preparative isolation of (+)-beta-eudesmol fromAmyris balsamifera

Summary Optically pure (+)-beta-eudesmol is a possible starting material for the synthesis of several termite defense compounds. A two step procedure for the isolation of gram quantities of (+)-beta-eudesmol from commercially availableAmyris balsamifera oil (syn. West Indian sandalwood oil), containing 8% beta-eudesmol, was developed. Step one consisted of an efficient vacuum distillation of the total oil. Step two was a medium pressure LC separation with an AgNO₃ impregnated silica gel stationary phase. Several other separation procedures failed due to the presence of many closely related sesquiterpene alcohols (75% of the oil).     

Intranasal irradiation with the xenon chloride ultraviolet B laser improves allergic rhinitis

We earlier reported that the 308 nm xenon chloride (XeCl) ultraviolet B (UVB) laser is highly effective for the treatment of inflammatory skin diseases. Since UVB irradiation has been shown to exert both local and systemic immunosuppression, we investigated the clinical efficacy of UVB irradiation in allergic rhinitis. In an open study, groups of patients with severe allergic rhinitis received intranasal irradiation with a 308 nm XeCl UVB excimer laser for two weeks. In the low-dose group (n=10), treatment was given twice weekly, starting with 0.25x the individual minimal erythema dose (MED), whereas patients in the medium-dose group (n=8) were treated four times weekly, starting with 0.4x MED. In each group, the dosage was gradually increased. Evaluation was based on the symptom scores. The effect of the XeCl laser on the skin prick test reaction was also studied. In the low-dose group, seven patients completed the study, and there was no improvement in the nasal symptoms. In the medium-dose group, the XeCl UVB irradiation significantly inhibited the rhinorrhoea, the sneezing, the nasal obstruction and the total nasal score (p<0.05). The XeCl UVB excimer laser also inhibited the allergen-induced skin prick test in a dose-dependent manner. These results suggest that the XeCl UVB excimer laser might serve as a new therapeutic tool in the treatment of allergic rhinitis.     

Untersuchung der Königskerzenblüten (Flores verbasci)

Ohne Zusammenfassung     

Matrix representation for combinatorics

Denumerably infinite matrices are introduced for the representation of combinatorial quantities. The purpose is to simplify and unify the presentation and to provide a method for the discovery of combinatorial identities and for proving them. The key concept is the derivative of a matrix.     

Primary XPS spectra of Ni and final state effects

By use of the loss spectra following the photoemission from the core levels of Zn diluted into Ni, the primary and inelastic electron contributions to the XPS spectra of Ni have been determined for the first time. The deduced primary photoelectron spectra of the 3d and 2p_{$\text{3}\text{2}$} levels of Ni are very similar and can be described by the recent final state calculation of Kotani and Toyozawa.     

Applications of the 308-nm excimer laser in dermatology

Excimer lasers contain a mixture of a noble inert gas and a halogen, which form excited dimers only in the activated state. High-energy current is used to produce these dimers, which have a very short lifetime, and after their fast dissociation they release the excitation energy through ultraviolet photons. The application of these lasers proved to be successful in medicine, including the field of ophthalmology, cardiology, angiology, dentistry, orthopaedics, and, in recent years, dermatology. For medical purposes, the 193-nm argon fluoride, the 248-nm krypton fluoride, the 351-nm xenon fluoride, and the 308-nm xenon chloride lasers are used. Recently, the 308-nm xenon chloride laser has gained much attention as a very effective treatment modality in dermatological disorders. It was successfully utilized in psoriasis; later, it proved to be useful in handling other lightsensitive skin disorders and even in the treatment of allergic rhinitis. This review summarizes the possible applications of this promising tool in dermatology.