The essential structures of ISP-I that influence serine palmitoyltransferase inhibition in Chinese hamster ovary cells.

We investigated the structure-activity relationship between various ISP-I (myriocin, thermozymocidin) analogous which has sphingosine-like structure and serine palmitoyltransferase (SPT) in Chinese hamster ovary (CHO) cells utilizing sphingolipid production as a marker. Our data suggest that the double bond and/or ketone group within the alkyl chain as well as the alkyl chain are necessary for ISP-I to inhibit SPT. In addition, a serine structure is necessary for SPT inhibitory activity, which confirms previous findings.

Aged human skin removes UVB-induced pyrimidine dimers from the epidermis more slowly than younger adult skin in vivo.

Although many studies have been reported on the repair of ultraviolet light (UV)-induced cyclobutane-type pyrimidine dimers (CPDs) in DNA, the effects of aging on the removal of UV-induced CPDs from the human skin epidermis in vivo remains uncertain. Therefore, we employed immunoblotting and immunohistochemical methods using monoclonal antibodies (TDM-2) to CPDs to study age-related differences in the time required for the in vivo removal of UVB-induced CPDs. The flexure surfaces of the upper arms of five young men were exposed to UVB light at a fluence of 35 and 700 mJ/cm2, and four older men were also irradiated with the same doses of UVB mentioned above. Each area of skin was biopsied before and immediately after irradiation, and at 4, 24 h, 2 and 4 days after irradiation in the younger group; and before and immediately after irradiation, and at 24 h, 4, 7, and 14 days after irradiation in the older group. A total of 108 DNA samples were taken from the epidermis of 108 biopsied specimens. These samples were immunoblotted using TDM-2 and the intensities of the immunoprecipitates were measured by photodensitometer. Our results show that the CPDs had been removed from the epidermis at 4 days after irradiation at either dose in the younger group, and between 7-14 days after irradiation in the aged group. The results of our immunohistochemical studies were consistent with those of our immunoblotting studies, and indicated that basal cells repair CPDs more quickly than prickle cells in the epidermis except the amounts at 24 h after UVB irradiation, and that the CPDs were removed by epidermal turnover after the nucleotide excision repair (NER). Our results showed age-associated decline in the NER in vivo, indicating high risk of UV-associated skin cancer.

Localized argyria 20-years after embedding of acupuncture needles.

We report a 66-year-old woman with localized argyria caused by embedding of acupuncture needles. Ten years after she had received acupuncture, she noticed two asymptomatic bluish macules on her right arm. A biopsied specimen from the macule revealed many brownish-black granules mainly located around the sweat glands and the blood vessels in the dermis. The X-ray examination of the extremities revealed numerous needle-like fragments around her extremities. "Embedding of needles" induces some serious adverse events. We should know the adverse events for the safety and health of patients.

Synthesis of the key intermediate, diethyl 2-acetylamino-2-(2-(4-octanoylphenyl)ethyl)propane-1,3-dioate, of the immunomodulatory agent FTY720 (fingolimod).

The key intermediate, diethyl 2-acetylamino-2-(2-(4-octanoylphenyl)ethyl)propane-1,3-dioate (13), for the immunomodulatory agent FTY720 (2: fingolimod) was synthesized via Michael addition of diethyl(acetylamino)malonate (6) to 4-octanoylstyrene (12).

Preparation of antibodies against a novel immunosuppressant, FTY720, and development of an enzyme immunoassay for FTY720.

FTY720 (1) is a novel immunosuppressant (immunomodulator), derived from ISP-I (2: myriocin and thermozymocidin). To clarify the pharmacokinetic properties of 1, antibodies against 1 were prepared and a competitive enzyme immunoassay (EIA) was developed. Two kinds of haptens, 3 and 4, for 1 were synthesized and coupled to ovalbumin (OVA). Rabbits were immunized with 3-OVA or 4-OVA, and corresponding antibodies were obtained. Both antibodies recognized the 2-amino-2-(2-phenylethyl)propane-1,3-diol moiety in 1. Using the anti-3-OVA antibody, a competitive EIA for 1 was developed and evaluated. The range of quantification by the EIA was 0.06-10 ng/mL. The application of the EIA has enabled us to measure the FTY720 concentration in serum after oral administration of 1 (1mg/kg) to rats.