Ground reaction forces during ambulation in parkinsonism: pilot study.

Gait abnormality in parkinsonism is unique and easily recognizable. A pilot study was designed at our Human Gait Laboratory to learn how this gait abnormality is reflected in ground reaction forces of patients with parkinsonism. The system permitted the collection of kinematic and force data from a subject in real time. Analysis showed an abnormality in the vertical force (Fz) component, the second peak being significantly reduced in size, with asymmetry in the duration of the stance phase. These abnormalities were also reflected in the stance phase and in the angular changes in the knee. Similar analyses should be helpful in following the progress of the disease.

DNA repair in skin of lupus erythematosus following in vivo exposure to ultraviolet radiation.

The in vivo repair of pyrimidine dimers induced in the DNA of skin of 9 patients diagnosed as systemic or discoid lupus erythematosus (LE) was measured. A small area of the buttock was exposed to radiation emitted from a Burdick UV-800 sunlamp. The number of pyrimidine dimers was measured by incubating the epidermal skin DNA with UV-specific endonuclease and sedimenting the DNA through alkaline sucrose gradients. The initial number of dimers induced following sunlamp exposure was 7.6 +/- 1.8 per 10(8) daltons DNA. The level of photorepair was measured by illuminating an area of the skin with greater than 450-nm radiation immediately following sunlamp exposure. We found that 56.5 +/- 9.5% of the dimers are photorepaired with 5 min of illumination. Excision repair was measured in an area of the skin covered for 2 and 24 h postirradiation. Approximately 44 and 81% of the dimers induced immediately following sunlamp exposure were removed at these respective times. These observations in LE are similar to those observed in the skin of normal individuals.

Increased helper-suppressor T-cell ratio in psoriasis.

Numerous investigations have suggested an immunologic pathogenesis of psoriasis and diminished suppressor T-cell activity of psoriatic blood. Consequently, a study was undertaken to explain whether diminished suppressor cell activity was a result of quantitative alterations of the T-lymphocyte subpopulation. Twenty patients with psoriasis and 20 normal control subjects were randomly selected. Our findings demonstrated a significant decrease in the percentage of suppressor cells (T gamma), a significant elevation of helper cells (T mu), and a highly significant increase in the helper-suppressor T-cell ratio (T mu/T gamma) of psoriatic blood compared with that of normal control subjects. Our study gives further support to the possible role of immunologic factors in the pathogenesis of psoriasis.

Photorepair of pyrimidine dimers in human skin in vivo.

The exposure of human skin in vivo to UV radiation emitted from a sunlamp induces the formation of pyrimidine dimers. The number of dimers, as detected by UV-endonuclease, decreases following exposure of the UV-irradiated skin to visible wavelengths of light. These results suggest that humans possess a mechanism by which pyrimidine dimers are photorepaired upon illumination of human skin in vivo with visible light.

Excision repair of UV-induced pyrimidine dimers in human skin in vivo.

The induction and loss of pyrimidine dimers in human skin in vivo was determined using UV endonuclease, alkaline sucrose sedimentations, and the fluorescent detection of nonradiolabeled DNA. The number of dimers induced following exposure of the skin to radiation emitted from a Burdick UV-800 sunlamp was quantitated by reacting the extracted DNA with Micrococcus luteus endonuclease specific for pyrimidine dimers. Exposure to 15 and 30 seconds of radiation emitted from this lamp produced the formation of 12.8 and 23.6 dimers per 10(8) daltons DNA, respectively. Approximately 50% of the dimers induced were lost 58 min after irradiation. Only a small percentage (less than 10) remained 24 hr postirradiation. These data partially characterize the process by which pyrimidine dimers are excised from human skin DNA in vivo.

Bilateral gaze paralysis with positive computerized tomography findings. A clinicoanatomic correlation.

The subacute development of an almost isolated bilateral gaze paralysis in a patient with mycosis fungoides allowed a unique opportunity for in vivo clinicoanatomical correlation when enhanced computerized tomography (CT) scan revealed two extremely small lesions of the pontine tegmentum. The larger lesion involved the region occupied by the medial longitudinal fasciculus and the paramedian pontine reticular formation (PPRF) bilaterally, and was alone sufficient to account for the eye movement disorder.

Folded skin associated with underlying nevus lipomatosus.

A mentally retarded female infant had abnormalities of the feet, hemiplegia, and an underlying nevus lipomatosus. To our knowledge, this represents the second reported case of marked folding of the skin; with an underlying nevus lipomatosus; this case demonstrated an association of this cutaneous disorder with multiple defects, including chromosomal abnormalities, which have not been previously reported.

Progressive cribriform and zosteriform hyperpigmentation.

Five cases of progressive cribriform and zosteriform hyperpigmentation are described. The following criteria were fulfilled: (1) uniformly tan cribriform macular pigmentation in a zosteriform distribution; (2) a histologic pattern that consisted of a mild increase in melanin pigment in the basal cell layer and complete absence of nevus cells; (3) no history of rash, injury, or inflammation to suggest postinflammatory hyperpigmentation; (4) onset well after birth with gradual extension; and (5) lack of other associated cutaneous or internal abnormalities. This appears to be a newly described entity, although it resembles a Becker's nevus without hypertrichosis or an typical café au lait spot. We believe that such progressive cribriform and zosteriform pigmentation is not uncommon.