Dehydroascorbic acid in urine as a possible indicator of surgical stress.

Background/aim: L-Ascorbic acid (AA) is the predominant circulating form of vitamin C found in human blood. It has been hypothesized that surgical stress increases the vitamin C metabolite dehydroascorbic acid (DHAA). Vitamin C is mainly excreted through the kidneys.

5-aminolevulinic acid-mediated photodynamic therapy of intraepithelial neoplasia and human papillomavirus of the uterine cervix--a new experimental approach.

The aim of this study was to treat patients for ectocervical dysplasia [cervical intraepithelial neoplasia (CIN) grades 1 and 2] and associated human papilloma virus (HPV) infections with photodynamic therapy (PDT). In 20 patients, 5-aminolevulinic acid (5-ALA, 12% w/v) was applied topically with a cervical cap 8 h prior to illumination. A thermal light source (150 W halogen lamp) emitting a broadband red light (total energy: 100 J/cm2, fluence rate: 90 mW/cm2) was used for superficial illumination of the portio.

Ambulant photodynamic therapy of superficial malignomas with 5-ALA in combination with folic acid and use of noncoherent light.

This study reports our first results of ambulant photodynamic treatment with 5-aminolevulinic acid (5-ALA) in combination with folic acid and subsequent illumination with a noncoherent light source. The compound was topically applied to avoid total body skin sensitivity which occurs in the case of systemic administration. If no therapeutic response could be proved, we added folic acid to 5-ALA for a further treatment attempt.

Antagonistic effects of combination photosensitization by hypericin, meso-tetrahydroxyphenylchlorin (mTHPC) and photofrin II on Staphylococcus aureus.

Photodynamic therapy involves the application of a photosensitizer activated by visible light to generate cytotoxic reactive oxygen. In addition to clinical investigations, in vitro studies concerning photodynamic potency of sensitizers as well as quantification of illumination procedures are necessary. In our investigation, the objective was to evaluate not only the effects of photosensitizer and light on Gram-positive Staphylococcus aureus, but also to investigate possible synergistic or antagonistic effects of these sensitizers.

Experiences of photodynamic therapy in dermatology.

From March 1988 to May 1994, 15 patients underwent the treatment protocol of superficial photodynamic therapy (PDT) in dermatological localized malignancies. Two tumours (one M. Queyrat of the penis, one basalioma) were treated primarily; the other 13 patients experienced relapses of underlying disease after treatment by surgery, radiotherapy or chemotherapy.